WEDNESDAY, June 17 may feature yet another upper-echelon severe weather event across the Midwest. A few significant (EF2 ) tornadoes are possible.
We're especially watching Missouri and Illinois, although parts of the Corn Belt are at risk too, as well as areas all the way to Ohio.
A few of the storms that form may produce destructive gusts (70 mph), tornadoes (some EF2 ) and hail. Areal coverage remains uncertain.
Low pressure passing through Minnesota will pull warm, humid air northwards. That will provide ample instability, or thunderstorm fuel.
A powerful jet stream, exceptional for June standards, will swing overhead, adding plentiful wind energy to the equation. Robust wind shear, or changing winds with height, will encourage storms to rotate.
It's likely there will be some morning downpours/storms as a warm front lifts through. It's unclear how quickly those appetizer storms will exit east.
The warm front will introduce rapid heating and "air mass recovery," once again juicing up the lower atmosphere for the main round of afternoon storms along the cold front.
We don't know what "storm mode" will dominate. Will we get a squall line with widespread destructive gusts and a few quick-hitting, brief tornadoes? Or will we see rotating supercells with a greater tornado risk? TBD.
For now, we ask you to stay tuned. We'll keep you updated.