ST RA I T S TOR M Jonathan Jordan During the early afternoon, high above northern Minnesota’s Boundary Waters Wilderness Area, a clash of atmospheric proportions is about to take place. A dividing line between a hot and muggy air to the south and drier, cooler air to the north has developed. An updraft of that hot soupy air bursts through the layer of coolness giving birth to a thunderstorm. It’s not an unlikely event during the month of July around these parts by any means, but all is now set in place for that simple garden variety thunderstorm to evolve into a summertime monster known as a derecho. The term derecho is Spanish for “straight” and over the next several hours the storm will proceed straight along that meteorological dividing line using it kind of like a mapping device, gaining size, speed, strength, moisture, wind, and producing lightning at increasingly prolific rates. On this day in early July, that atmospheric dividing line, invisible to the naked eye, heads off to the east and south a bit, right smack dab through the Straits of Mackinac. Not long after its inception and its downdraft gusts have already leveled swaths of pines across the northernmost woodlands of Minnesota, the towering thunderhead splits into multiple cells of regenerating nastiness. The close-knit family of storms moves powerfully out over Lake Superior just south of Thunder Bay, Canada. It storms on, growing ever more potent, widespread and dangerous, whipping up ferocious and mountainous waves on the great sprawling open lake. Making landfall, now, in the Upper Peninsula of Michigan at Ontonagon and cutting across the Keweenaw Peninsula without delay, the congealing line of storms takes on the shape of a bow and has swollen to more than fifty miles across at its leading edge which has darkened to an inky blue and developed a menacing snowplow-like shelf cloud across its low-hanging front. Behind the shelf cloud the storm’s innards glow an otherworldly pale, almost-neon, green. The narrow peninsula stabbing up into Lake Superior was nothing more than a speed bump. By late afternoon, it skirts the southern reaches of Lake Superior once more and then blows ashore at Grand Marais. Wind driven rain and hail lash against the cliffs along the Pictured Rocks National Lakeshore. The leading edge of the storm now stretches from Whitefish Bay down over northern Lake Michigan just off of Naubinway. It’s regeneration and intensification continues. At Cedar Haven cottage on Marquette Island which is along the northern shores of the Straits of Mackinac, the evening has an odd feel to it. For one thing, the sunset was more than an hour earlier than usual after another gloriously sunny midsummer afternoon. And, actually, there really wasn’t a sunset. Instead of the usual glowing golden-orange-pink evening treat, things just suddenly seemed to darken over the sunset end of the bay. The evening retreat of gulls, herons and other water foul out to their Goose Island rookery for the night has taken place uncustomarily early. The birds seemed to have a hurry to their winging, unlike most evenings when they seem to lollygag along in the waning light.
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