Folks are sitting in western Nebraska right now anxiously awaiting a boom or bust storm chase where a stout cap holds the deciding card between a memorable supercell thunderstorm or blue skies that fade into a quiet sunset. Meanwhile, I'm having a normal Monday workday back in Illinois while mostly hiding from the air outside. My driveway thermometer says it's 96.9 deg F, the nearby airport observation says 95 degrees with a dew point of 69. My Mondays usually involve putting together a longer-range update for folks on the Canadian Prairie. In doing my weekly medium-long range forecasting, I started to get some thoughts about the near-term future of the severe weather / storm season in the Central U.S.
The risk for isolated to scattered severe thunderstorms continues across the Northern Plains and Upper Midwest through Tues, June 18th, but an expansive ridge of high pressure will have things generally on the isolated, low-predictability side for the rest of this week.
The transition from the very active 2024 spring storm season into whatever the summer storm season has in store for us has certainly begun with the northward progression of the jet stream. It's going to quiet down for a bit, and then what?
Looking around the corner, it's easy to see how we could end up with a renewed run of organized severe weather from the Northern / Central Plains into the Midwest in the days 6-10 time frame, or roughly June 22-26.
Here's how it might happen...
Over the weekend an upper level disturbance will sweep from the Northwest US into the Great Lakes with a surface low pressure system tracking near/along the U.S. and Canada border. A cold front will extend southward into the Plains and Midwest and could serve as a focus for one or two days of organized severe storms as it sweeps through.
Early next week, guidance has the weekend frontal boundary stalling across portions of the Plains and Midwest, with another burst of jet stream flow interacting with the front through mid-week.
As this frontal boundary meanders north and south with shortwaves running over the top of it, the potential would exist for episodic severe weather events along the boundary from the Plains into the Midwest.
This is of course all speculation at best - what days and what locations feature the greatest risk for severe storms? All to be determined... This has historically been a fairly classic late-spring, early summer recipe for an active stretch of severe storms, perhaps with multiple days with the potential for supercells, tornadoes, and linear storm complexes thanks to a synoptically favorable background state and the right mesoscale dominoes falling from there.
This weekend, the first upper-level wave and frontal boundary swing through the Northern Plains and Upper Midwest:
Early next week, the frontal boundary stalls across the Plains and Midwest with another upper-level disturbance bringing renewed jet stream support for organized thunderstorms along the front:
We'll see... I'll be watching anxiously, dreaming of the next time I get to stand in front of a thunderstorm and eventually feel that rain-cooled air as I endure a bit of a summertime heatwave here in the Midwest.