As we head into the final days of July and first days of August I've got high confidence in a low predictability pattern of episodic severe weather across portions of the Midwest from July 29 - August 3. The background state will closely resemble recent patterns that provided consecutive days of severe thunderstorm activity over the same region in early to mid July.
At lower levels of the atmosphere, a dominant Bermuda High will pump a steady feed of moisture northward from the Gulf of Mexico into the Mid-Mississippi and Ohio River Valleys. At the same time, a series of shortwaves will ride over the top of a shifting southwestern U.S. ridge. The result is a classic pattern for "ridge-riding" thunderstorm clusters and an elevated risk for daily corridors of severe weather regionally.
You know, those days storm chasers and meteorologists geek out over 6,500 joules per kilogram of explosive instability with an incoming MCV ready to spark 60,000 foot tall thunderstorms that prompt severe t-storm warnings for 90 mph winds.
While the coming week will be quite stormy anywhere from the Northern Plains into the Northeast and Southern U.S. there will likely be a preferred corridor for more organized daily severe weather risks including many of the same metropolitan areas that've been hit hard by severe weather in recent weeks - Des Moines IA, Madison WI, Chicago IL, Indianapolis IN, and St. Louis MO.
Now, I've got high confidence in the following pattern coming to fruition and the period from July 29 - Aug 3 likely featuring quite a few severe reports in this corridor... but I have low confidence in the day to day details. What happens on day 1 will impact day 2, which impacts day 3, etc. Monday, July 29 looks like it could be the first day of elevated severe weather potential, perhaps somewhere from Des Moines to Chicago. Beyond that, we're in watch-and-see mode. The watch part of this one is becoming fairly evident as of this Saturday afternoon writing - so let's see.
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