INCA-CE Newsletter 7 (Aug. 2013)

INCA-CE Newsletter

Issue No. 7

August 2013

Editor: CGS plus d.o.o.

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Weather INCA-CE Project Weather connects Central Europe

Photo: Benedikt Bica

INCA-CE Newsletter

Issue No. 7

August 2013

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Nowcasting for better planning of weather-related activities Why a nowcasting system?

Many activities in our daily lives depend on the prevailing and future weather conditions. In the past 10 to 15 years, significant advances have been made in weather forecasting and warning systems to enable, amongst other things, an optimized planning of activities. These advances succeeded as a result of modern computer and information technologies as well as the enhancements and refinements in physics and dynamics of the numerical weather prediction (NWP) models. NWP models can anticipate changes in weather patterns a few days in advance.

However, for local weather events arising in a short period of time like thunderstorms, it is only possible in most cases to specify the exact position and intensity of the event several hours in advance. The forecasting methodology focusing on this time span is called nowcasting. It optimally combines all available observational data with information from meteorological models in order to get an exact and detailed image of the current weather and the weather expected within the next few hours.

Numerous end users need this accurate and reliable weather information in their daily life to guarantee timely actions in the warning procedures, and thus protect people and environment against severe weather impacts. The integration of INCA information into the warning procedure allows for an increase of cost effectiveness and security in relation to weather dependent activities.

In road safety, INCA facilitates the more efficient planning of preventative spreading in winter which must be executed up to three hours before a snowfall event.

Additionally, it supports deicing measures. These measures are strongly connected to the type and concentration of salt used, as well as the optimal saltspreading time depending on the forecasted road surface temperature. Consequently, INCA contributes to the increased safety of drivers, the reduction of costs because of improved staff organization and lower salt consumption, and the reduction of environmental damage from over-salting.

In operational hydrology, INCA precipitation data are used as input to hydrological models and might increase the potential of the hydrological forecasting system in

8.6.2012 6 UTC, Surface Frontal Analysis, Source: ZAMG

Weather forecast of NWP models for Vienna from 31 July 2013 to 4 August 2013, Source: orf.at predicting an extreme runoff event.

INCA is also useful in the field of civil protection. The organizers of open-air events need accurate weather information for the timely cancelling of an outdoor event, if necessary.

How does a nowcasting system work?

Conventional NWP models have their limits in forecasting rapidly evolving weather processes which occur in small regions. Depending on the model, the forecasts are computed every 3-12 hours, and the results are available

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with a lag of 4-5 hours compared to the lastly integrated observation.

Therefore, several weather services develop and apply nowcasting methods in addition to the classical numerical forecasting.

The nowcasting system INCA (Integrated Nowcasting through Comprehensive Analysis), for example, is characterized by two essential features: i) INCA combines in real-time the available observations of weather stations, radar and satellite data and analyses of meteorological models.

Nowcasting then describes a small-scale weather

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development of the next two hours (this time slot might be larger for temperature – depending on the atmospheric conditions) by observation-based extrapolation; ii) the second feature – generally after two hours – is the linear transition of the observation-based extrapolation into the output of the underlying NWP model.

This process is finalized after six hours so that the only information of INCA is the

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forecast of the NWP model after a forecasting period of six hours. However, this forecast is downscaled, and thus provides weather information with higher spatial accuracy.

The INCA system was set up in Austria at the Central Institute for Meteorology and Geodynamics (ZAMG) in 2003, and is a fundamental part of the INCA-CE project.

Supercell at Lake Balaton, Source: OMSZ, Ákos Horváth

INCA-CE - a project that brings together meteorological services and users of Central Europe How the project idea was born Every year, Central Europe is affected by weather extremes challenging civil protection authorities, hydrologists and road maintenance services to timely warnings. Through INCA-CE, a deepened transnational cooperation between meteorological services and three application areas has been established.

This guarantees for both enhancements of meteorological products in the sense of end user friendliness and standardized information exchange across borders.

The INCA-CE project thus joins meteorological forecasts and warnings with practical applications of various Central European organizations in civil protection, road safety and

Cover images of the different INCA-CE newsletters operational hydrology. At present, it is the only project throughout the world which connects cooperation to such an extent with respect to its transnational and multidisciplinary framework.

16 key partners from eight Central European countries accept the challenge to work on standardization and harmonization tools.

INCA is continuously refined to better respond to the concrete needs within the three application areas.

Thereby, an integral part is a

feedback loop between model developers and end users. For one institution alone it would be impossible to cope with all the necessary tasks.

Aims and structure The INCA-CE project aims at reducing adverse effects of weather-related natural disasters (e.g. windstorms, flooding, mudflows, icing) by establishing a state-of-the-art, high-resolution, real-time analysis and forecasting system on atmospheric, hydrological, and surface

"This project is implemented through the Central Europe Programme co-financed by the ERDF"

conditions. The main goal is the improvement of risk management standards and methodology in order to enable more detailed assessments and warnings in a transnational manner.

The project is structured in six work packages (WPs). WP1 includes the management and coordination (reporting between partners but also between the partnership and the Central Europe Programme).

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Meteorology and Water Management, IMGW, Warsaw, Poland n PP4, Czech Hydrometeorological Institute, ČHMÚ, Prague n PP5, Hungarian Meteorological Service, OMSZ, Budapest n PP6, Regional Agency for Environmental Protection, PCRAFVG, Palmanova, Italy n PP7, Environmental Agency of the Republic of Slovenia, ARSO, Ljubljana Civil Protection Organizations: PP8, Security Center Burgenland Company, LSZB, Eisenstadt, Austria n PP9, Provincial Government of Lower Austria, NOEL, Sankt Pölten n PP10, Ministry of the Interior, BMI, Vienna, Austria n PP12, Ministry of Interior of the Slovak Republic, MV SR, Bratislava n PP13, Disaster Management Directorate of Somogy County, SMKVI, Kaposvár, Hungary n PP15, Department of Crisis Management, WZK, Żywiec, Poland n

Scheme of essential INCA-CE components WP2 focuses on communication and dissemination of results (e.g. preparation and distribution of newsletters, two project videos, web portal).

The visualization of different weather parameters (http://www.inca-ce.eu/CEPortal/index.html; more details on page 6) is also available to the interested general public to track the future weather developments.

The transnational cooperation facilitates considerably the anticipated improvements in crisis management and risk prevention: the data flow across borders enables amongst others the disposability of data in border domains, and can improve the timely actions of the respective authorities before the occurrence of a severe

weather event. This is shown in a multiplicity of pilot studies in WP5 and elaborated in the article on page 9.

In WP3, one goal was to identify the current warning situations against severe weather in each of the three application areas in the different Central European countries (page 9). Thereafter, common requirements from the application areas have been deduced to improve the modules of the nowcasting system INCA in WP4 (see page 5). Of course, this needs a very close collaboration between nowcasting information providers and end users.

Partnership and duration INCA-CE has been implemented through the Central Europe Programme,

co-financed by the European Regional Development Fund from April 2010 to September 2013, and led by Yong Wang from the Austrian Central Institute for Meteorology and Geodynamics (ZAMG). The partnership included many disciplines from eight Central European countries – project partners (PP) from meteorological and hydrological services, and from institutions of the different application areas:

Road Safety Organizations: PP11, Provincial Government of Lower Austria, NOEL, Sankt Pölten n PP14, CGS plus d.o.o., Ljubljana, Slovenia n

Meteorological and hydrological services: PP1, Central Institute for Meteorology and Geodynamics, ZAMG, Vienna, Austria n PP2, Slovak Hydrometeorological Institute, SHMÚ, Bratislava n PP3, Institute of n

"This project is implemented through the Central Europe Programme co-financed by the ERDF"

Mudflow and Landslide Modeling: PP16, Fraunhofer-Institute of Optronics, System Technologies and Image Exploitation, IOSB, Karlsruhe, Germany

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New INCA developments

RMSE of the nowcasts as a function of forecast time for an Alpine area within 15 convection days in 2011, Source: ZAMG One major advantage of the INCA nowcasting system compared to others is that it provides accurate and reliable information about several weather parameters (and not precipitation alone).

a limited area model (ALADIN) in dynamical adaptation mode or generally, by using high resolution NWP models (e.g.

AROME). Preliminary results

indicate more realistic wind fields in complex terrain.

Topographic effects on wind in INCA were also studied in

cases of downslope windstorms in the High Tatras area and compared to WRF model outputs of similar horizontal resolution.

Convective nowcasting The INCA module of 'precipitation nowcasting' has been further developed by including the life cycle of convective cells into the algorithm. This module has been put into pilot implementation in Austria during the convective season 2012. The results show that RMSE out of the convective cells approach is smaller compared to the kinematic extrapolation approach in the respective area.

Wind gust nowcasting and topographic effects Topographic wind effects have been treated by high resolution downscaling using

Model First Guess for INCA 10-m Wind, from ALADIN (10km, top left), ALADIN in dynamical adaptation mode (DADA) (2.5 km, top right). Zoom over South Tyrol: ALADIN (bottom left), DADA bottom right), Source: ZAMG

"This project is implemented through the Central Europe Programme co-financed by the ERDF"

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Work on gust nowcasting mainly focused on atmospheric conditions related to convective activity (thunderstorms). A downburst potential parameterization has been developed. It could be shown that a physical approach of parameterizing gusts related with thunderstorms ('downbursts') is able to indicate a potential of hazardous situations and can be beneficial in civil protection applications. For non-convective gusts, different methods/ parameterizations have been implemented and tested with respect to civil protection usage. First results are promising, but might need some recalibration in order to avoid high false alarm rates.

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The Land SAF data have been implemented in a new INCA surface temperature module, Source: ZAMG Surface temperature nowcasting

orbiting satellite (Land SAF data).

Nowcasts of surface temperature are crucial for precise forecasts of road conditions. Thus, the main focus was on improved surface/road temperatures especially in the temperature range close to the freezing point. The basic version of surface temperature nowcasting has been refined by adding land surface temperatures from polar

Code optimization The whole model code has been optimized (through redesigning and parallelization) to shorten the model runtime. The success of parallelization can be demonstrated in values: only 5% to 20% of the initial model runtime is needed now! In addition, the storage usage has been optimized by using

dynamical allocation of the memory instead of the current static memory allocation for particular INCA modules. In addition, the Input/Output module was standardized, followed by code refactoring and rewriting of the code from C to C++ programming language. The modified code is already used in the respective applications and can also be combined with parallel environments of different calculation platforms.

Transnational web portal A transnational web portal for displaying INCA nowcasting information A very good example of the transnational character and dissemination of results of the INCA-CE project is the development and provision of a common nowcasting web portal covering the entire Central European area. It provides nowcasting information in high spatial and temporal resolution of

temperature, wind, wind gusts and precipitation. Since INCA relies on many different sources of observation data, a transnational agreement on the exchange of such data had to be reached. Weather services from Central Europe are now exchanging observation data and therefore allow for the computation of INCA on the whole domain. The substantial redesign of INCA

resulted in an increase of the computational performance which is needed to run the model at high resolution on such a large domain.

In the entire domain, INCA is run by the Slovak Hydrometeorological Institute (SHMÚ) for wind, wind gusts and temperature. Due to the high amount of radar data which is required for the precipitation nowcasts, such a centralized computation is not

"This project is implemented through the Central Europe Programme co-financed by the ERDF"

feasible for precipitation. The approach taken is the combination of all regional precipitation nowcasting simulations into one precipitation composite. Thus, each participating weather service (ZAMG, SHMÚ, IMGW, ČHMÚ, OMSZ, PCRAFVG, ARSO) computes precipitation nowcasts for the respective national domain. These precipitation fields are then merged into one Central

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Central European web portal: Different parameters, maps and function settings (update frequency, opacity, speed of loop) can be chosen. INCA domains contributing to the precipitation composite: each weather service is computing INCA precipitation for the national domain: ZAMG (red), SHMÚ (blue), IMGW (green), ČHMÚ (cyan), OMSZ (purple), PCRAFVG (black) and ARSO (yellow)

European precipitation composite by ZAMG and displayed on the web portal.

Mobile version of the Central European portal with ZAMG position (found through IP address) marked with a cross, and uncertainty in position marked by the red circle

The Central European web portal is built on open source technology and implements (besides standard features such as zooming and panning) functionalities for an enhanced user experience.

Location determination (based on IP or GPS for handhelds) allows for finding the users current position on the map. This is especially useful for end users (e.g. from civil protection or road safety) who have an outdoor job and permanently need to assess the current weather situation in their surroundings.

"This project is implemented through the Central Europe Programme co-financed by the ERDF"

Especially for outdoor users, the mobile version of the web portal is of fundamental support. Once the web portal site is accessed with a smartphone/tablet, a mobile version is provided (optimized for small screens and touchscreens). This feature is quite useful for outdoor activities of both professional users and the general public.

Additional features include the address search and a UTC/CET time switch.

The Central European web portal supports the end users by giving an accurate and reliable overview of the transnational weather situation, and thus allows for planning activities accordingly in the three application areas.

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National web portals (clockwise from lower left): Italy (FVG region), Austria, Czech Republic, Poland, Slovakia, Hungary, Slovenia

Usage statistics of the web portal indicate a growing interest in the Central European web portal. Both professional users and the general public access the site to get up-to-date information about weather conditions in their vicinity or the entire Central European region.

In addition to the Central European web portal, each weather service provides a national web portal to the end users.

National web portals While the Central European web portal gives an overview of a few parameters for the entire Central European area, a higher degree of detail,

additional meteorological parameters and additional technical functionalities become necessary for certain user groups. In order to satisfy the needs of the end users, national web portals have been designed and implemented during the INCA-CE project. These implementations are specifically designed and adapted for the requirements in each country.

In Austria, for instance, the web portal is tailored to the needs of road safety and civil protection: colour scales (for temperature) highlight the 0 degree line, which is very important for road safety applications; similarly, colour scales for wind speed and

wind gusts are chosen in accordance with the end users from civil protection. Time series can be displayed by clicking on the map, which makes the assessment of meteorological conditions much easier for single points.

Other implementations of the national web portals have their focus on other applications, meteorological parameters or design features.

Moreover, the technical implementation of the web portal is also dependent on many boundary conditions, such as available hardware, software, data policy and so on.

"This project is implemented through the Central Europe Programme co-financed by the ERDF"

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Transnational strategy in the three application areas INCA-CE project partners have elaborated transnational strategies of using the INCA nowcasting system in three application areas: road safety, operational hydrology and civil protection.

The transnational strategy of road safety states that all Central European countries can experience severe winter conditions such as snow, ice and frost. Such conditions make the transportability difficult and cause several challenges for the road maintenance services. By using reliable weather information and short-range weather forecasts, the road winter maintenance staff can make more reasonable decisions on treatment procedures concerning the amount of salt applied, as well as the optimal location and time span. Such optimization can result in reducing the total amount of spread road salt, and therefore diminishing harmful impacts on the environment. The INCA system shows lots of potential in being used by the road sector in Central European countries. The INCA forecasts can easily be incorporated into existing Road Weather Information Systems (used as input for different road weather models focusing on the prediction of road surface temperature and road state)

or can even be used as standalone weather information.

Accurate predictions of road conditions increase the road safety and thus decrease the potential risk of accidents.

The potential of the use of nowcasting data is also described in the transnational strategy of operational hydrology. The attention is especially paid to the flash flood forecasting which is highly topical in operational hydrology nowadays. The success of hydrological forecasts is strongly correlated to the success of the precipitation forecast usually obtained as the output from NWP models. The precipitation nowcasting, which is derived from the extrapolation of radar echo, can significantly improve the first six hours of the precipitation forecast. Thus, the use of precipitation nowcasting in hydrological forecasting systems can result in more precise hydrological forecasts. The shared experience with the flash flood forecasting systems tested in operation in Central European countries and several case study examples proved that every flash flood has to be evaluated separately. Different categories of warning strategies are suggested, based on the two most

important factors influencing the accuracy of the hydrological forecast: the location of the catchment with respect to the available weather radar system and the presence of rain gauge station(s) within the catchment area. Although the stochastic approach is highly recommended, the deterministic flash flood forecasting system can also help to warn inhabitants in endangered areas. The cooperation with end users has a key influence.

Transregional and transnational cooperation is

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necessary for the successful run of the system in crossborder areas. The real-time exchange of radar data and data from rain gauges across the borders can improve the measured and predicted precipitation fields also in the neighbouring areas.

Civil protection is one of the main end user of meteorological information.

Weather-related severe events (e.g. floods, storms and droughts, fire) often threaten life and properties of people and thus can lead to important economic losses despite of the rapid

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development in modern technologies. Civil protection from natural disasters may require an enhanced organization, predominantly in the awareness and preparedness of the general public. Moreover, civilprotection operations are successful only in case the rescue teams are best coordinated, which is strongly dependent on accurate realtime information (weather situation, alerts, position of the rescue units, etc.). The experiences from case studies show that civil protection authorities need detailed and precise analyses of the weather situation and also reliable short-term weather forecasts. Such detailed weather information helps in clarifying the warnings issued by the national meteorological services, reduces the number of false alarms and increases the confidence in alerts. In addition to the requirements on high resolution and accurate weather data, the timely dissemination of information is very important as well. Comprehensive nowcasting products enable faster and better decisions.

The INCA-CE strategy paper proposed three actions to increase the effectiveness of the civil protection operations: 1. INCA-SWING (Severe Weather INterpretation Guide) application to help the users in better understanding and evaluating nowcasting products, 2. INCA-MCPEX

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(Meteorological-Civil Protection EXercise) aiming at increasing the preparedness to deal with extreme weather situations (see also INCA-CE Newsletter No.6), 3. INCA-ISW (Impact of Severe Weather) to enhance the transregional communication and knowledge about the financial impact and predictability of significant weather events.

During the project, the applicability of these three concepts was tested and evaluated in the Central European area.

It was concluded that the information about the reliability of the nowcasts might be one of the key products in the future. It might support the decisions in severe weather cases when evacuation of inhabitants is necessary and both the public and legal authorities have to be informed in a short period of time.

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DRSC RWIS developed by CGS plus d.o.o.

INCA products in DRSC RWIS

ROAD SAFETY: pilot implementations and case studies Pilot implementation of the INCA forecasts into Slovenian road weather information system (RWIS)

The Slovenian Roads Agency (DRSC) manages the main and regional roads with a total length of almost 6,000 kilometres. It undertakes technical, developmental, organizational and

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INCA SMS application for mobile phone with INCA forecasts for the selected road weather station locations

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administrative tasks relating to the construction, maintenance and protection of main and regional roads and some dual carriageway sections, as well as tasks relating to freight and passenger road transport.

DRSC has 20 Road Weather Stations (RWS) installed on representative road sections all over the country. All of them use GPRS data transfer and are equipped with embedded road and meteorological sensors. Most common measurements are: road temperature (surface, 5 cm depth and 30 cm depth), thickness of water film, salt concentration, freezing point temperature, road condition, air temperature and humidity, dew point, intensity, amount and type of precipitation and visibility. Some of them also measure wind speed and direction.

Road Weather Information System (RWIS) is the most important tool for winter

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maintenance that offers information about the current meteorological state of the road network (wet, ice, snow, etc.). The need for road weather forecast has been identified in the last years.

Pilot implementation of INCA was performed in the frame of the INCA-CE project. INCA products (i.e. surface temperature and precipitation fields) are available in RWIS and highly valuable to the road maintenance service. For now they are used stand alone. INCA can also be used as an input into the METRo model for road weather forecasting in the future.

Comparison of wind speed data between INCA and road weather stations The case study analysis is based on the data of the Šumljak road weather station between 19 and 21 September 2012 when typical bora high wind speeds

The Razdrto-Vipava motorway section was closed after the extreme bora wind overturned a truck on 9 March 2010, Source: Blaž Samec (Delo d.d.)

Bias and RMSE of INCA wind speed nowcasts compared to measurements from the respective road weather station. Note: the abscissa represents the lead time (from 0 to 12). occurred along the motorway section near Podnanos (Slovenia).

The comparison results show that high/extreme wind speeds can be predicted several hours ahead with sufficient accuracy as well as the start and end time of high/extreme wind speed events.

It is important to accurately predict high (extreme) wind speeds on the roads. This allows the motorway companies to optimize their decision system for opening/closing the motorway in case of strong wind. Such decisions are delicate because, on the one hand, they can cause economic damage, but on the other hand, it is necessary to ensure the safety of drivers.

Comparison of road surface temperature data between INCA and road weather stations The case study analysis is based on the data of the Bandera road weather station between 6 and 12 February 2013 when a typical meteorological situation for the winter season occurred with road surface temperatures around 0°C (with high variations between day and night) on the motorway near Senožeče (Slovenia).

The results show that INCA nowcasts of surface temperatures can be informative enough for predicting the road surface temperature. However, the accuracy of the forecasts is sufficient only for the first few

Bias and RMSE of INCA road surface temperature compared to the measurements from the road weather station. Note: the abscissa represents the lead time (from 0 to 12).

"This project is implemented through the Central Europe Programme co-financed by the ERDF"

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hours of the forecast (i.e. for lead times up to 2-3 hours).

Road surface temperature is one of the most important parameters which support anti-icing and plowing/deicing operations of winter road maintenance. Optimizing the winter road maintenance decisions (treatment locations, timing, types and rates) has an important impact on the roadway efficiency and the potential risk of accidents. An accurate prediction of road weather conditions is important for providing safer roads, minimizing the environmental damage from over-salting and for cutting the winter road maintenance costs.

INCA analysis field of cumulated precipitation from 15 March 00 UTC to 16 March 12 UTC, Source: ZAMG

Potential of INCA in accurate forecasting of heavy snowfall on Austrian roads On 15 and 16 March 2013, a heavy and regionally restricted snowfall event occurred in the northern Alps of Lower Austria. In this area, between 10 and 25 cm of snow fell during one night (as shown by the INCA analysis field of cumulated precipitation) and caused massive traffic problems.

This case was selected for further investigation because the global ECMWF model and the regional NWP models (ALARO5) forecasted only very little snowfall for this time period.

Weather situations with heavy postfrontal precipitation due to effective orographic

ECMWF forecasts of 24h accumulated precipitation [mm] (left panel: 15 March 00 UTC - 16 March 00 UTC, right panel: 16 March 00 UTC - 17 March 00 UTC) with initialization time 15 March 00 UTC, Source: ZAMG

precipitation enhancement are rather challenging for NWP models because drying effects are dominating due to sinking air masses in higher altitudes. Furthermore, such orographically influenced events are usually restricted to small areas and characterized by a very high spatial variability. Hence, they cannot be simulated accurately by NWP models with a rather coarse resolution. Good forecasts

ALARO5 forecast of 24h accumulated precipitation [mm] (15 March 00 UTC - 16 March 00 UTC) with initialization time 15 March 00 UTC, Source: ZAMG

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Poland Meteorological tools: INCA precipitation and temperature forecasts Hydrological tools: MIKE NAM and SMHI HBV hydrological models Slovakia Meteorological tools: INCA precipitation field analyses – 1 km spatial resolution, 10 minutes time step

INCA forecast field of cumulated precipitation from 15 March 12 UTC to 16 March 06 UTC based on the INCA run on 15 March 00 UTC, Source: ZAMG and exact warnings in such situations can only be issued by experienced forecasters and the help of high resolution nowcasting tools such as INCA. The case study shows that the main advantage of INCA compared to NWP models is – in addition to the higher resolution – the consideration of observations and radar data especially for nowcasting applications up to 12 h. But, on the other hand, it also shows that even INCA forecasts have their limits in case of complex terrain and erroneous station measurements (poor station density, measuring errors in case of snowfall).

Nevertheless, the use of INCA as a supplement to the NWP models enables more precise warnings and increases the forecast skill. End users in road maintenance appreciate the reliable and accurate INCA information.

OPERATIONAL HYDROLOGY: pilot implementations and case studies Hydrologic forecasting centres in CZ, PL and SK have a lot of experience and long lasting tradition in flood forecasting.

Forecasting of flash floods is of high interest because of severe impacts which could be reduced by increasing the predictability. Many different forecasting tools have been developed in the last years to accept the challenge of flash floods forecasting.

These forecasting tools are usually connected with nowcasting systems providing the key inputs for hydrological forecasting systems, e.g. precipitation in high spatial and temporal resolution, which is necessary for hydrological forecasting in

small watersheds. The INCA system is operational for flood forecasting. Generally, INCA provides the analyses of precipitation fields or (and) nowcasting of precipitation fields. These essential data enable hydrologists to apply the hydrological models on small spatial extents (up to 1 km) and to simulate runoff data 1 to 8 hours prior to a flood event.

The hydrological modelling systems may differ from one hydrological service to another. The operative usage of the different systems is considered in the following case studies: Czech Republic Meteorological tools: INCA precipitation nowcasting (3h), COTREC, CELLTRACK Hydrological tools: Fuzzy logic model for flash flood forecasting, HYDROG rainfall runoff model

"This project is implemented through the Central Europe Programme co-financed by the ERDF"

Hydrological tools: rainfallrunoff model HEC – HMS, peak estimation system based on CN method and a system based on the combination of flash flood potential and threshold values of precipitation.

Flooding events in the Sola river basin Case studies were carried out for both the Żywiec and Pewel Mała water gauge stations in the Sola river basin in the period '28 June 2011 02 UTC to 5 July 2011 06 UTC during which flooding was observed.

In total, 174 simulations were performed in this time slot based on the INCA 1 hour precipitation nowcasts. Only precipitation nowcasts were taken under consideration in this case study to compare the amount of forecasted precipitation by INCA with the values measured at the two weather stations.

Runoff forecasts are underestimated in the rising phase but overestimated during recession. This is caused by over- (or under)estimation of input

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Observed hydrograph (blue line) and runoff forecasts for Żywiec (top) and Pewel Mała (bottom) rain gauge stations, Source: SHMÚ

precipitation. In turn, the over- (or under)estimated precipitation can be caused by several factors: (i) the observed precipitation values at the rainfall stations (used in the model) might not be representative for sub-

catchments, (ii) the calibration of the model might not be optimal, or (iii) the INCA nowcasts are uncertain. The rainfall-runoff model considers INCA precipitation forecasts at the locations of weather stations, which can

largely differ because the spatial information is omitted.

Most of the simulations show the right tendency, but at present their quality is not sufficient enough for the operational use.

"This project is implemented through the Central Europe Programme co-financed by the ERDF"

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Threshold exceedance of accumulated 10 minute precipitation sums, Source: SHMÚ Flooding event in the Rožňava region Another case study is about a flash flood event in the Rožňava region on 12 May 2013. The INCA precipitation analyses were considered as optimal data source for the evaluation. The data analysis concentrated on the threshold exceedance of accumulated INCA precipitation sums compared to the values specified in the flash flood potential map. The potential for flash floods is classified

from 'extremely high' to 'low' depending on the slopes and hydro-geological transmissivity of the 1 km pixels.

The original INCA precipitation analyses (in 10 minutes time steps) were transformed to accumulated precipitation fields with a 10 minutes accumulation interval and then compared with the critical values in the flash flood potential map. The threshold exceedance was registered during the most

Failure in forecasting the flash flood in Jičínka watershed by all nowcasting systems investigated, Source: SHMÚ

intensive rainfall between 12:20 UTC and 13:10 UTC. The figure shows that precipitation thresholds were exceeded in some parts of the area but not in the area actually hit by the flash flood (denoted by the red circle).

However, if the system is run in real time, the coloured areas should be considered as areas prone to flash flood risk.

The urban areas should be recategorized, based on conditions such as impermeable surfaces and limitations of sewer systems.

In summary, the combination of the flash flood potential map with empirical threshold values of critical precipitation accumulations has the ability to be run operationally and thus to improve the flood response. One major advantage is its simplicity and the coverage of the whole Slovakian territory. The inclusion of INCA precipitation nowcasting would increase lead times for the warnings.

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Flooding event in the Jičínka and Luha regions On 24 and 25 June 2009, a series of heavy flash floods occurred in the north eastern part of the Czech Republic. In Jičínka watershed, it caused one fatality, in Luha catchments three fatalities.

Damages in both regions exceeded tens of millions of EUR. The potentials of the INCA system and other nowcasting systems were evaluated and tested for the respective events.

In the Jičínka river basin, the nowcasting systems fail in forecasting the flash flood event: the signals of high flash flood potential occur only when the actual flash flood occurs.

The hydrological warning system based on INCA precipitation nowcasts successfully forecasted the flash flood event in the Luha river basin. It was possible to predict the flash flood event within 150 minutes in advance!

Successful forecasting of the flash flood in Luha catchment by all nowcasting systems, Source: SHMÚ

"This project is implemented through the Central Europe Programme co-financed by the ERDF"

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Left: 1h wind gust forecast of INCA for the Lake Balaton at the OMSZ webpage; Right: Storm-warning valid at the time of the forecast, Source: OMSZ

CIVIL PROTECTION: pilot implementations and case studies Pilot implementation of the INCA forecasts in the Somogy County and at the Lake Balaton

The Somogy County (area of 6,035.86 km²; 345,000 inhabitants) is located in the south-western part of Hungary, and several parts of this region (Balaton, Zselic, Dråva River) are attractive tourist destinations. Thus, protection of tourism-related cultural and sport mass outdoor events is a very

Warning chain during mass events at the Lake Balaton, Source: DMDSC, OMSZ

important task of the Disaster Management Directorate of Somogy County (DMDSC) and requires close cooperation with the meteorological service. The number of large events (exceeding a number of 1,000 visitors) is increasing.

Whereas only 40 of such events were registered in the year 2007, already 164 events were organized in the Somogy County in the year 2012.

Depending on the size and character of the event, a separate disaster management plan is used to be prepared by the civil protection authorities. The decision about cancelling or relocation of festivals or sport competitions because of severe weather requires very accurate weather information with at least 2h lead time. The Hungarian Meteorological Service (OMSZ) runs the local implementation of the INCA system, and distributes the nowcasts of 2m temperature,

"This project is implemented through the Central Europe Programme co-financed by the ERDF"

10m wind and precipitation to DMDSC experts since June 2011.

The role of INCA nowcasts within the warning chain is twofold: it helps to improve the basic warnings issued by the meteorological service and to provide additional, detailed information about the temporal and spatial evolution of weather hazards to the Disaster Management experts. The high-resolution outputs are useful for the planning of rescue operations and the distribution of civil protection units as well as for specifying the information provided to other authorities or to the public. During the project, INCA nowcasts for 23 significant weather situations were evaluated in cooperation with DMDSC (severe weather during mass events or fire events). In addition, the INCA nowcasts are regularly updated on the OMSZ

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INCA-CE Storm front on 2012-06-08 at 16:00

INCA-CE Storm front on 2012-06-08 at 17:00

INCA-CE Storm front on 2012-06-08 at 18:00

INCA-CE Storm front on 2012-06-08 at 19:00

Comparison between the observed storm front and the outer edge of predicted storm front between 4 p.m. and 7 p.m.

website. Thus, currently issued weather warnings can continuously be compared with the forecasted distribution of wind or precipitation.

Thunderstorm event in Austria on 8 June 2012 A storm front moved from the west to the east of Austria on 8 June 2012 between 4 p.m. and 7 p.m.

A comparison between the analysis and nowcasting data showed that the storm front

was generally well predicted

by INCA but there were some difficulties in accurately predicting individual severe thunderstorm cells in the respective regions. For small scale events, the weather forecasts might still be uncertain to some degree.

However, the experiences show that INCA analyses represent well the actual weather developments. The merging of INCA outputs with reporting information of civil protection authorities is seen

as very valuable in the future disaster management.

Tests of INCA-SWING algorithm for a case study in Slovakia A correct forecast of precipitation is one of the most important and most difficult tasks of meteorological services. The development, character and intensity of precipitation depend on many factors (e.g. orography, stability of air mass, horizontal and vertical

"This project is implemented through the Central Europe Programme co-financed by the ERDF"

wind distribution). The uncertainty of precipitation forecasts is especially high in conjunction with local, isolated thunderstorms, which may evolve rapidly (20-30 minutes). Stability indices (e.g.

CAPE, Lifted Index) are used as an indicator of thunderstorm potential, calculated by the INCA system. To make the interpretation of several meteorological parameters easier for the civil protection authorities, the INCA-SWING (Severe Weather

INCA-CE Newsletter

Issue No. 7

August 2013

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Left: Output of INCA-SWING diagnostics showing the areas of observed and potential thunderstorm activity valid for 22 June 2013 1500 UTC; Right: Corresponding INCA-SK 1h precipitation analysis, Source: SHMĂš INterpretation Guide) application was proposed to provide comprehensive information about the potential for severe weather events. The algorithm identifies the existing precipitation patterns and highlights the areas with thunderstorm potential in the near future (0-2h). This concept has been tested on several cases of severe weather. On 22 June 2013, several thunderstorms formed within a warm and unstable air mass over many parts of Central Europe (mainly Austria, Hungary and Slovakia). Hail and windstorms were reported. The output of SWING algorithm indicated the presence of thunderstorms, as well as the potential of further development of convection in Slovakia and northern Hungary. The extension of this application to the whole Central European domain was tested as well.

Civil protection during the Balaton cross-swimming event 2013 A new algorithm was implemented to calculate the wave-height on the Lake Balaton based on INCA-HU nowcasts. This algorithm was implemented and tested during the Balaton crossswimming on 20 July 2013.

The outputs were generated hourly and disseminated to forecasters and civil protection experts of the Somogy County. The distribution of wave-height seemed to be realistic: 20-30 cm wave heights were forecast at places, where 1520 km/h average wind speeds occurred in the morning hours (which corresponds to general experiences and reports from the area of the event). The nowcasts correctly showed that the wind speed and the wave height decreased, which enabled to continue the swimming competition.

Wave height (colour, cm) and 10m wind (arrows, m/s) analysis of INCA-HU tested during the Balaton cross-swimming event on 20 July 2013, Source: OMSZ

"This project is implemented through the Central Europe Programme co-financed by the ERDF"

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We got feedback from stakeholders Road safety

total, more than 25 million EUR were spent on the implementation of winter service, and on top of this 9 million EUR for spreading material.

How is the winter road maintenance organised in Slovenia and who carries it out?

Ljiljana Herga Head of Road Maintenance and Safety Division, Slovenian Roads Agency (DRSC)

There is absolutely no need to argue that winter road maintenance is closely related to weather. What were the conditions on the Slovenian roads during the last winter? What were the costs of winter road maintenance?

The last winter represented a major challenge for our winter maintenance service since it was among the most severe winters in the recent decades.

Due to its extreme intensity, all available equipment had to be used several times; nevertheless, it was not always possible to ensure the passability of roads. As planning of winter maintenance costs is done on the basis of three-year averages, there was a large gap between the planned and used resources last winter. In

Slovenia has ≈38,000 km of roads. Municipalities are responsible for management and maintenance of 32,000 km of local roads and public paths, the Slovenian Roads Agency (DRSC) for 6,000 km of main and regional roads and the Motorway Company of the Republic of Slovenia (DARS) for 800 km of motorways.

All maintenance work on public roads managed by the DRSC is outsourced, although DARS has their own winter maintenance service. DRSC divided their roads into nine regions according to the climate characteristics and has concessions with seven road maintenance companies.

Do winter services use weather information in their work: Please describe your system.

Weather information is important in supporting a variety of everyday winter maintenance operations. We receive special region-based forecasts from the Slovenian Environment Agency.

“From the INCA-CE project we are able to use the state-ofthe-art weather forecasts of very high spatial and time resolution and thus improve our winter road maintenance and road safety on Slovenian motorways.”

Marko Korošec, supervisor of the Road Weather Information System (RWIS) at Slovenian main motorway company DARS, Slovenia

However, more detailed weather information such as road surface temperature and condition is needed to support anti-icing and plowing/de-icing operations.

For this purpose we use the road weather information system (RWIS) which collects weather data from road weather stations and represents them in web application. We have 20 road weather stations installed on representative road sections all over the country. Most common measurements on the road weather stations are: road temperature, thickness of water film, salt concentration, freezing point temperature, road condition, air temperature and humidity, precipitation (intensity, amount and type).

How important is a high resolution weather forecast – nowcast for you?

Due to the diverse topography, the road weather conditions may differ considerably even in a small area; therefore, high

"This project is implemented through the Central Europe Programme co-financed by the ERDF"

resolution weather forecasts are very important for the operation of winter services.

Such forecasts enable us to foresee the road surface temperature in relation to the quantity and type of precipitation. This allows us to get ready in advance, which often means big savings in the operation of winter service, while appropriate and timely actions also ensure greater safety of the roads.

Are you familiar with the INCA-CE project and how do you assess its results?

I am familiar with the INCA-CE project as it was presented in a number of road-related events in recent years. A pilot implementation of INCA high resolution weather forecast and nowcast was carried out within our road weather information system, which represents a significant step towards further development of this system. In my opinion, the project results are very beneficial and useful for the operational functioning of winter service.

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Operational hydrology

August 2013

Editor: CGS plus d.o.o.

And finally, one of the strongest flooding events in the Slovakian part of the Danube occurred in June 2013. It was assessed as a flood event with a 100-year return period.

Apart from these regional floods, many local floods caused by torrential precipitation occurred in the summer months of 2012 and 2013.

Danica Lešková Head of Department of Hydrological Forecast and Warning, SHMÚ

There is a close link between operational hydrology and the prevailing weather conditions. How do you generally evaluate the years 2012 and 2013 with respect to flood events? Can you provide numbers of damages due to flooding events?

2012 was a calm year when almost no serious flood event occurred. The only exception was a flood in late winter/spring months in the upper Vah River basin, which was caused by melting snow.

The first half of 2013 was in straight contrast to 2012. Due to melting snow, many flood periods occurred in winter time. In many areas, the highest (3rd) degree of flood activity was exceeded – the situation was most serious in Nitra and Ipel river basins.

Fortunately, no casualties were claimed, and thanks to new mobile flood protection barriers in cities along the Danube (like Bratislava, Komárno, Štúrovo) almost no damages in these cities (during the above mentioned great Danube flood) were observed. Damages in smaller locations caused by the above mentioned regional and local floods in winter and summer months reached damage of millions of EUR, but the exact sum is hard to estimate from our point of view.

How is protection against flooding organized in Slovakia, by whom?

Flood protection in Slovakia is under the responsibility of two ministries: the Ministry of Environment is the coordinator for municipalities, the Slovak Water Enterprises and for SHMÚ, and the Ministry of Interior is responsible for civil protection. In the case of serious flood events, the Ministry of Defense provides help.

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“Flood forecasting is the precondition for preventative flood protection. ProRaab (a) – the flood forecasting system of Hydro Burgenland – requires precise precipitation forecasts and benefits from the results of INCA-CE.” Karl Maracek, Head of division Hydrographic Service, Office of the Government of Burgenland, Section 9 – Water and Waste Management, Austria

SHMÚ monitors the situation on rivers and is responsible for issuing the hydrologic forecasts and warnings (in the case of possible flooding). The Slovak Water Enterprises maintains and keeps the river channels in the optimal “antiflooding state” and together with civil protection institutions it is responsible for the safety of inhabitants and their properties in the case of flooding. For flood protection on local levels, the respective local municipalities are responsible.

Do hydrological services use weather information? Please, can you describe your system?

Weather information, mainly about precipitation, is the key input into our forecasting system. Without the information about current and predicted weather, the hydrological forecasting is a “mission impossible”. We use forecasts of precipitation and temperature from the ALADIN model as well as from forecasting systems with shorter lead times, i.e. nowcasting systems.

"This project is implemented through the Central Europe Programme co-financed by the ERDF"

How important is a high resolution weather forecast – nowcast for you?

Nowcasting is the key product for prediction of hydrological events with short duration and small spatial extent – torrential rains followed by flash floods. Nowcasting can estimate possible affected areas (watersheds) very exactly not only from the spatial, but also from the temporal point of view.

Do you know the INCA-CE project? If yes, how do you assess the results of the project?

Products from this project, especially hydrological products, are made exactly for our needs – just for the prediction of flash floods. So my answer is yes, we know the INCA-CE project. We receive precipitation inputs on an internal line, and the data are available on our intranet in the form of graphical maps or tables.

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Issue No. 7

Civil protection

August 2013

Editor: CGS plus d.o.o.

was rather extreme with respect to the heat-wave and drought, with damages in the range of ten million forints, and still counting.

How is protection against severe weather events organized in Hungary, and by whom?

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“Densely populated and intensively used areas need to be protected against extreme weather impacts. Therefore, the INCA-CE project can provide precise information so that the whole warning system is improved.”

Zsolt Neszményi, General Director of the Government Office of Somogy County, Hungary

Disaster management experts use INCA-based information on a daily basis, and during a particular incident or at the time of a mass event the decisions are based on the INCA hourly updates.

Tibor Juhász Government Emissary, Chairman of the Somogy County Defense Committee and Head of the Government Office of Somogy County

There is a close link between civil protection and the prevailing weather conditions. How do you generally evaluate the years 2012 and 2013 with respect to civil protection activities?

Can you provide numbers of damages due to severe weather events?

There were 3,000 different incidents in total, most of them in connection with extreme weather. We had to get prepared for the most extreme weather conditions – in March 2012, the wildfires were very common, while a blizzard as never seen before was raging in Somogy County on 14-15 March 2013. In spring 2013, we were affected by floods and inundation, and also by landslides. July 2013

How important is a high resolution weather forecast – nowcast for you?

It is very important – not only in my opinion, but also according to our experience.

Nowcasts are crucial predominantly in connection with heavy rain and thunderstorms, because this information allows for optimizing the actions in smaller areas of operations.

Furthermore, nowcasting information supported our prevention experience, e.g. during various summer mass events. Based on the detailed forecasts we were able, for instance, to postpone the Lake Balaton Swimming Contest (with thousands of contestants) because of the severe weather warning. A new element in the prevention chain is the Lake Balaton wave map, which we used during the Lake Balaton Swimming Contest and the Blue Ribbon Sailing Race.

Disaster management

Source: István Szabó

professionals using this information were extremely pleased.

Do you know the INCA-CE project? If yes, how do you assess the results of the project?

I know the project, and I was participating in the INCAMCPEX [Meteorological Civil Protection Exercise], along with the whole Somogy County Defense Committee, the leaders of public offices and various law enforcement and rescue services. The results of the INCA-CE project were a huge help, for instance, during the blizzards and thunderstorms of this year. It is safe to say that

"This project is implemented through the Central Europe Programme co-financed by the ERDF"

these results saved many lives. But in my opinion, the largest achievement of this project was that it taught disaster management officers and meteorologists to work more closely together in order to protect Hungarian citizens more efficiently.

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during these events. In summary, it seems that severe weather events become more frequent which means an increasing challenge for civil protection authorities.

How is protection against severe weather events organized in Austria, and by whom?

Siegfried Jachs Head of the National Crisis and Disaster Management and Civil Protection, Ministry of the Interior - Department II/4

There is a close link between civil protection and the prevailing weather conditions. How do you generally evaluate the years 2012 and 2013 with respect to civil protection activities?

Can you provide numbers of damages due to severe weather events?

Just recently, in June this year, we saw a major flood disaster which affected several countries in Central Europe.

Germany was mostly hit by the floods, but the impact in Austria was also very high.

The damages resulting from this event are estimated to reach about 900 million EUR. During the last two years, we also had a number of severe local rainfalls although no other devastating event occurred. Furthermore, we had two years with heavy snowfall at the beginning of the year. Fortunately, there were no major human losses

The responsibility for civil protection is largely delegated to the state governments and not to the central government. Response to disasters and disruptive events is organized on four administrative levels, the municipal level, the district authorities, the state governments and the federal government. In case of a disaster resulting from severe weather, usually the district authority takes the operational lead. The alarm centres of the nine states are responsible for the dissemination of warnings to districts and municipalities.

They receive information and expertise from ZAMG, the national weather service, which runs the INCA model and provides an expert portal for civil protection authorities.

Do civil protection services use weather information?

Please, can you describe your system?

Mainly the alarm centres of the nine states use weather information in their daily business and during extreme events. Due to an arrangement with ZAMG, warnings are at first

disseminated to the alarm centres which evaluate a possible impact and forward warnings and instructions to local authorities and response organizations like the fire brigades. There are also dedicated lines of communication to the regional ZAMG offices if it is necessary to consult a meteorologist for more specific advice and recommendations.

How important is a high resolution weather forecast – nowcast for you?

The Ministry of Interior itself has no urgent need for nowcast information as the perspective of the ministry is more a strategic overview. On the other hand, nowcasting is of course of utmost

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importance for local authorities and first responders who have to act and decide on very short notice.

Do you know the INCA-CE project? If yes, how do you assess the results of the project?

As a member of the INCA-CE consortium I am of course very well aware of the project.

INCA-CE is a very important project for the improvement of forecasting in the Central European region and is also a very important milestone with regard to the enhancement of the cooperation of relevant actors in that region which includes civil protection authorities, weather services and hydrological institutes.

From Central Europe to the globe The World Meteorological Organization (WMO) has seen the valuable potential of the INCA-CE project and has, therefore, chosen it as the World Weather Research Programme/Forecast Demonstration Project (WWRP/FDP). By the support of WMO, INCA is intended to be adopted in various countries all around the world, and – in this context – the acquired know-how, expertise and up-to-now experiences are aimed at being exchanged. Especially in

"This project is implemented through the Central Europe Programme co-financed by the ERDF"

developing countries, new cooperation is anticipated assuring least possible cost for local research and development. In the meanwhile, ZAMG coordinates 24 partners coming from Austria, the Czech Republic, Germany, Hungary, Italy, Poland, Slovakia and Slovenia (all involved in INCA-CE), and additionally from Belgium, China, Croatia, Israel, Switzerland and Turkey.

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INCA after INCA-CE In the course of the INCA-CE project, INCA has been implemented at all partner institutions and will continuously be run in the whole Central European domain in the upcoming three

years. In this period, the partnership plans to meet at least every year to discuss major findings, results, problems and approaches to solving any problem.

INCA analysis field of cumulated precipitation from 25 February at 00 UTC to 26 February at 12 UTC, Source: ZAMG

Extreme weather events during project implementation Austria Flooding event in Austria in February 2013 On 25 and 26 February 2013, a flood occurred in the federal state of Burgenland in the south-eastern part of Austria.

It was caused by heavy precipitation in combination with warm temperatures and a strong snow melt. The precipitation amounts were around 20 – 30 mm (regionally up to 40 mm due to orographic enhancement), which fell within 24 hours only (25 February 00 UTC – 26 February 00 UTC) and caused a massive increase in river discharges.

A blocking high pressure system over Scandinavia and a large low pressure system over Italy led to a persistent easterly and south-easterly flow over Central Europe. On the border of these two dominating pressure systems, which laid approximately

across Austria, warm and moist air masses from the south were mixed with cold air masses from northern and eastern Europe (occlusion front line). Strong lifting processes in this area led to heavy precipitation and due to the strong horizontal temperature gradient an alternation of solid (snowfall, sleet) and liquid (rain) precipitation occurred.

Such weather conditions potentially lead to heavy precipitation events which can be especially abundant due to orographic effects. The southeasterly flow resulted in an effective precipitation enhancement in the upper catchment area of the Raab River. The large scale weather situation changed after a few days with the filling of the low pressure system over Italy and the propagation of the high pressure system to Central Europe. However, a precise prediction of the location of the occlusion front with its sharp temperature gradient

and precipitation field is rather challenging for NWP models.

The NWP model ALARO5 underestimated the precipitation amounts in the investigation area shown by the cumulative plot.

The dark blue line indicates the observed precipitation amounts which reached more than 30 mm. The model runs two days before the event (red and green lines) completely underestimated the amounts and also the onset of the precipitation was simulated about 12 hours

later. The model runs from 25 February properly simulated the temporal distribution of the precipitation but with amounts around 17 mm only.

With INCA, the precipitation field is quite similar to ALARO5, but the precipitation amounts are significantly higher and comparable to the observations. Due to the higher spatial resolution (1km), the precipitation patterns in INCA are also much more accurate than in ALARO5. The strengths of INCA are definitely in the nowcasting range up to 12h.

Observed precipitation amount (TAWES) and ALARO5 forecasts with different initialization times, Source: ZAMG

"This project is implemented through the Central Europe Programme co-financed by the ERDF"

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INCA forecast field of cumulated precipitation from 25 February at 12 UTC to 26 February at 12 UTC, Source: ZAMG In conjunction with these atmospheric conditions, flood alerts were frequent in the southern Burgenland region and in Styria. More than 30 operations of fire brigades were counted, and in some districts the Austrian Federal Armed Forces supported these actions. LSZ-B was in regular contact with other emergency organizations (blue light driving) and ZAMG. The latter provided detailed weather forecasts in time and space from the INCA nowcasting system. The available INCA output supported a lot the decisions of authorities at LSZ-B but also of regional hydrologists (e.g. from Provincial Government of Styria - Water Department).

However, in the future, the uncertainties in precipitation forecasts should be minimized, and further enhancements in the hydrological model are needed such as implementing new retention storages, new calibration of the forecast model and configuring the snow melt module in order to achieve a better quality of flood forecasts at the Raab River.

Hungary Snowstorm in Hungary on 1415 March 2013 Severe wind (exceeding 100 km/h in gusts) and heavy snowfall occurred over a large part of Hungary on 14-15 March 2013. The combination of snow and strong wind caused very low visibility and extraordinary high snowdrifts blocking several thousands of people travelling by cars despite of extreme weather conditions (15 March is a national holiday in Hungary).

The distribution of the strongest wind gusts (maximum in the west of

INCA-HU 10m wind and gust analysis valid for 14 March 2013 1700 UTC Hungary and at the Lake Balaton) was well matched by operational INCA analyses and forecasts.

Italy Hail damages to vineyards on 22-23 July 2011 A strong hail storm which occurred in the night between

22 and 23 July 2011 will be remembered for large damages to many vineyards in the Collio area (Gorizia, Italy).

During the afternoon, the satellite images showed the sky clear from any kind of convective clouds. From 19 UTC, the Fossalon's radar indicated some convective cells along the western foothill area of Friuli Venezia Giulia. Around 21 UTC they

Photos taken in the morning of 23 July 2011 in the Plessiva area (Gorizia, Italy) after the hailstorm during the night of 22-23 July. a) hail-stones which hit the Plessiva area b) vineyard damages.

Source: Jana Movja

"This project is implemented through the Central Europe Programme co-financed by the ERDF"

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MSG satellite at 9:00 UTC shows the top of the almost circular cloud with cloud-to-ground lightning (CESI-Sirf). Maximum reflectivity (VMI above 55 dBz close to the Latisana highway) recorded by the Fossalon's radar at 9:05 UTC. moved to the plane, intensifying while shifting to the Collio region where, around 22 UTC, an intense hailstorm hit the area, causing damages to about 300 ha of vineyards. The accumulated rainfall between 22-23 UTC was of 47mm, with peaks of up to 16mm in 5min. The images document the events in the Plessiva area.

Thunderstorms with floods in Friuli Venezia Giulia on 12 September 2012 During the late morning of 12 September 2012, the western part of the Friuli Venezia Giulia region was hit by a strong thunderstorm with precipitation rates above 50mm/h causing the flooding of houses, basements, underpasses and roads.

Flooding in the western part of Friuli Venezia Giulia. Source: Il giornale della Protezione Civile

Delays occurred along the highway A4 near Latisana due to large hailstones of up to 3 cm. The synoptic situation at 00 UTC was characterized by a low over the Scandinavian peninsula, associated with a cold front that descended along the Central Europe, preceded by a line of instability. At 6:30 UTC, the first cells were generated along the pre-frontal line and

around 9 UTC, a large cell, generated by the outflow of the previous ones, was born around the Latisana area where the damages concentrated.

Thunderstorms with strong wind in Friuli Venezia Giulia on 24 September 2012 An intense thunderstorm associated with heavy

Maritime pines thrown down by the strong wind along the Belvedere of Aquileia road during the evening of 24 September 2012. Source: local newspaper Il Piccolo.

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Damages in Trieste due to the strong bora wind. Source: Daniele Petronio precipitation and very strong winds characterized the evening of 24 September 2012. A series of thunderstorm cells, aligned as a bow-echo shape, passed through the Friuli Venezia Giulia region between 17-18 UTC. The maximum rainfall rate recorded in Udine was 40 mm/h, but the largest damages were caused by the strong wind which blew linearly, putting down many high trees along the road of the Belvedere of Aquileia (UD). The maximum recorded wind speed was 24.1 m/s at the Fossalon's station.

Damages in Friuli Venezia Giulia due to strong wind gusts on 1-2 March 2011 On 1-2 March 2011, the Friuli Venezia Giulia region was affected by strong bora wind causing severe damages, with the strongest consequences in the city of Trieste. A strong pressure gradient between

the depression cantered on the Tyrrhenian Sea and an anticyclone over northeastern Europe with very high values of surface pressure of about 1040 hPa led to a remarkable mean wind of 7080 km/h in Trieste where, in the night between 1-2 March, reached the peaks between 90-100 km/h. The gusts had repeatedly exceeded 150 km/h with a peak of 163 km/h. This is the strongest bora burst ever recorded by ARPA FVG-OSMER instruments since at least 1985.

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Blasted trees in the Tuchola Pinewoods.

Source: borowiak.flog.pl

within six hours. As a result, the Miedzianka River (tributary of the Nysa Luzycka River), which flows in the Bogatynia region, burst its banks. The river flooded almost the whole town. The flood resulted in fatalities and collapses of historic buildings.

Broken bridges and damaged roads were also the effect of the flood.

Twister in the north of Poland on 14 July 2012 On 14 July 2012, a twister was detected in the north of Poland. The radius of the twister was about 400 meters.

The phenomenon was estimated as F2 in Fujita scales (rates by damage caused). As a result, over one hundred buildings were damaged, the electricity was

Poland Flood in Bogatynia on 7 August 2010 On 7 August 2010, heavy rains with storms appeared in the south-west of Poland resulting in local rapid rises of water levels. 160mm of precipitation was measured at the Bogatynia rainfall station, including 112mm, which fell

Damage caused by flood in Bogatynia. Source: PAP, Grzegorz Hawałej

"This project is implemented through the Central Europe Programme co-financed by the ERDF"

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cut off and many trees were fallen. One person died and several were injured. The Tuchola Pinewoods were also damaged (about 400 hectares were destroyed).

Slovenia Floods in the central and south-eastern parts of Slovenia in September 2010 During the weekend of 17–19 September 2010, one of the

August 2013

Editor: CGS plus d.o.o.

worst floods occurred in the country's history. The most affected areas were the capital Ljubljana and its surroundings as well as the region of Posavje in the southeastern part of Slovenia.

Thousands of people were affected or threatened by water. Many roads and houses in a number of towns and villages were flooded. The initial damage was estimated to be around 15 million EUR. Three people died.

We had fun

The beginning of the INCA-CE project was marked by a startup phase, which was also devoted to get to know each other and to get an idea what the INCA model is all about.

Already during our kick-off meeting, we were able to eliminate some

Water disaster struck in Ljubljana, Slovenia in September 2010.

Source: MORS

South American example and much closer to our target region. However, this little town on the Spanish island of Mallorca is also outside of our target region of Central Europe (although our INCA domain almost covers it).

Location of INCA in Mallorca, Source: www.inca-ce.eu/CE-Portal misunderstandings: in our project, “INCA” has very little to do with the South American civilization of the past, nor it is related to the hidden city of Machu Picchu.

One of our project colleagues even discovered a location much less outdated than the

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After our kick-off meeting in Vienna, we got to know each other and we were able to outline the basis of our project ideas and goals and the INCA nowcasting system as well. The kick-off meeting was followed by bi-annual progress meetings which were hosted in turns by the participating countries: AT, DE, CZ, SI, PL, HU, IT, SK. These meetings were important reunions to advance our project plans, coordinate activities, develop new ideas, etc. Furthermore, each of those meetings was marked by a specific character of the region: from hiking on the snowy peaks around Zakopane (PL) to swimming in the chilly early spring sea of

"This project is implemented through the Central Europe Programme co-financed by the ERDF"

Grado (IT); from rural taverns in Slovenia to an impressive banquette in Kutna Hora (CZ).

Besides our scheduled progress meetings, we had a few reunions gathering subgroups of our project consortium. During these meetings, special topics were handled, such as the web portal development, advances in the three working groups

Ernst Böcskör in INCA, Source: E. Böcskör

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The specific character of the respective regions of bi-annual progress meetings (1. Zakopane, 2. Grado, 3. Ljubljana, 4. Kutna Hora) (hydrology, road safety, civil protection), administrative meetings, etc. One of the larger side-meetings was the WP coordination meeting in Smolenice (SK), which certainly was remarkable in many aspects: We were housed in a historical castle (now owned by the Slovak Academy of Sciences), we received first-hand information about the flash flood events in Pila from the local civil protection authorities and discovered the secret cellars of the Smolenice castle.

Yes, we had fun during implementation of INCA-CE project. But we also believe that the improved INCA nowcasting system will facilitate the better planning of weather-related activities in Europe and that the Central European community will benefit from the results of our project.

Project Identity Card: Title: INCA-CE — Integrated Nowcasting System for the Central European Area Acronym: INCA-CE Programme: Central Europe Duration: 1 April 2010 – 30 September 2013 (42 months) Partnership: 16 partners from 8 Central European countries Lead Partner: Central Institute for Meteorology and Geodynamics (ZAMG) Webpage: http://www.inca-ce.eu/

"This project is implemented through the Central Europe Programme co-financed by the ERDF"

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