The storms that hit the Midwest today were awe-inspiring and frightening. They spawned something like two dozen tornadoes in a “super outbreak” that experts compared to one in 1974.
At the least, it’s reassuring that the National Weather Service can track dangerous storm cells as closely as they do, and issue updated warnings every 15 minutes. Still, there’s a random, evolving element to tornadoes that means they can appear in unpredictable places, sometimes before the authorities know they’re there.
A day in advance, we knew that a line of “unstable” tornado weather would move across our county, and approximately when, so that’s good. You can make preparations around that information – candles, lamps, food, work schedule. But whether tornadoes would actually form, and where exactly they would go, nobody knew.
It turned out that in the late afternoon today, a line of severe thunderstorms that spawn tornadoes was headed directly toward Cincinnati. When it was only 20-30 miles away, for some reason, this storm track split, and the tornadoes and high winds that were part of it went to the north and to the south. People died in both places, including three in our county, about 20 miles south of us. (Although I gotta say, the chances of survival in a house like ours, with a basement and heavy retaining walls built deep into the earth, are pretty good, even if a tornado goes right overhead.)
From a California perspective, it’s hard to get a bead on Midwestern weather (if anyone even tries). In California, when storms come in from the Pacific, they’re relatively predictable in terms of strength, direction and time of arrival. Here, the confluence of warm air coming northward from the Gulf, ambient winds from the West, and cold air coming southward from Canada makes predictions much more difficult. Dangerous weather springs up quickly, seemingly out of nowhere. I follow the NWS site closely, and on a given day you can look at the radar images at, say 1 p.m., and see nothing for hundreds of miles in all directions. When you look at them two hours later, you might see that a major storm has blossomed and is bearing down on your area.
From the LA Times:
Friday’s outbreak of tornadoes was “a one-in-20-year event,” spawned by a combination of a cold front, high humidity and warm weather, said Angie Lese, a meteorologist with the National Weather Service in Louisville, Ky.
“We knew it was going to be bad. All the ingredients came together for a significant outbreak,” she said. “We will have more severe weather this season. This isn’t the last of it, I’m sure. But this is pretty rare.”
Good.