MEXICO REPORT SEEKING SHELTER FROM SCREAMING BLUE NORTHERS

from March 17-30, 2023 The Log Digital Edition

san diego fish report

By: CAPT. PAT RAINS

“March winds blow” isn’t just a whimsical adage like April showers and May flowers. But, for springtime boaters in Mexican waters, it’s the key to route planning. Here’s why.

D uring March and early April, a unique weather pattern called a Plateau High can develop over the mountain plateaus of mid and southern Nevada, often forcing the surface winds to flow outward from the center of the high-pressure area.

For boaters in northwest Mexico, winds that originated in the Nevada Plateau are felt as cold and dry, blowing from t he north toward the south and southwest. Of course, most of the time, you’ll fi nd good cruising and fishing weather. Not every breath of wind from the north came from Nevada. Sometimes it’s just a short-duration blast of the north wind that spilled over from a winter storm sliding down from the Pacific Northwest.

But when a Plateau High settles in, as it can do during March, those north winds in northern Mexico tend to increase (15 to 28 knots or more) and can blow steadily, day and night, sometimes lasting five or six days with no respite.

That’s called a “Nortada” or a “Norther.” When a true Norther blows, it can rake Baja California’s Pacific coast down to about Magdalena Bay, and in the elon- gated Sea of Cortez, a bad Norther can affect the whole 700-mile length.

Northers usually start in the far upper Sea of Cortez, then may build in strength and spread laterally to affect outside Baja. They taper off in strength as they move south. True Northers rarely reach south of Isla Cerralvo on the Baja side or south of Punta Mita on the mainland side.

Screaming Blue Norther

A Norther’s gale-force winds and big square seas can disrupt navigation for commercial ships, so they can easily inhibit movement for us relatively small c ruising yachts and sportfishers. Once we get securely anchored or plugged into a cozy slip, it isn’t easy to go elsewhere.

As a Norther persists, the sea surface and horizon can become obscured b y salt spray and a lifting blue-white spume. Visibility plummets tremendously, and windshields get shellacked. The sky even darkens. That’s what’s called a Blue Norther.

But for us cruising folks and sportfishers, when we get pinned down for d ays on end, when we can’t poke our noses out, when boaters at anchor can’t even get ashore, that’s when the screaming starts – on the VHF radio, across the cockpit at each other, and screaming into the wind-swept heavens: Stop Blowing!

Seriously though, the reasonable approach is to know in advance (a.) when a Norther will start and (b.) where to head for shelter before it does.

Wind Watching

Here’s how. Watch the U.S. weather reports for the first signs of a potential Norther in Mexico. That will be a zone of high pressure (perhaps 1039 millibars or higher) that stops moving and gets stationary over mid-to-southern Nevada. Subsequently, high-wind warnings may be posted for land traffic traversing the desert and mountain passes, such as big rig trucks that get blown over.

For an excellent online weather forecast covering the outside of Baja, the entire Sea of Cortez, and the mainland as far south as the Gulf of Tehuantepec, I suggest you visit https://www.nhc.noaa. gov/text/MIAOFFPZ7.shtml. This text report is produced by NOAA, the National Oceanic and Atmospheric Administration, the boaters’ friend.

NOAA gives an offshore marine forecast, ideal for major weather events, long offshore leaps, and crossing from Baja to the mainland or back. Yet the winds and sea conditions closer to shore can sometimes be quite different.

If you have a good internet connection, I suggest using the Windy.com app. It’s good for recreational boating in Mexico because it gives almost real-time wind and sea conditions and considers specific terrain features that influence coastal weather. It can even predict conditions up to seven days in advance.

For example (see photo), Windy. com shows three days before the start of a dreaded “Elefante,” a strong but narrow blast of wind that ventures down gaps in Baja’s Sierra San Francisco and sprays out into the Sea of Cortez at 15 to 25 knots. Elefantes often surprise boaters otherwise enjoying bland traveling weather in the central Sea of Cortez.

Windy.com aids recreational boaters in Mexico with its almost real-time weather maps. It can sometimes predict wind conditions up to seven days ahead, like this graphic showing an Elefante blasting between Santa Rosalia and San Francisquito.

The Corumel is another example. This unique breeze sometimes starts from the Pacific and across a terrain gap, then funnels down into the La Paz area at night. Windy.com is graphics-heavy, so if your internet connection is marginal, use the previous link for text.