Over the next 48hrs Wisconsin will see decent thunderstorm activity. The bulk of activity coming overnight and shifting into the southern half of the state Wednesday.
The best chance for storms will be tonight and again Wednesday night. Perhaps some scattered t-storm activity south during the day Wednesday. The severity of thunderstorms should be limited somewhat by overnight timing/focus. We are watching closely. Some uncertainty remains, especially for Wednesday.
TONIGHT/ WEDS AM - Strong Storms Expected
Thunderstorms will develop across Wisconsin tonight. Some could be strong to severe, especially in west-central Wisconsin. Large hail and damaging wind gusts are the primary threat. The axis for the strongest storms will be from La Crosse to Appleton. Heavy Rain of 1-3" is expect across portions of central and southern Wisconsin, wherever t-storm activity is greatest.
Discussion - 1000-2000 j/kg MUCAPE suggests even if storms are not surface based they will still be elevated and potentially strong. Large hail would be the primary threat should strong/severe storms develop. Cannot rule out tornado threat southwest of I-94 with an impressive amount of low-level shear and strengthening low level jet. Models are overdoing surface moisture and timing is unfavorable, but other factors suggest strong/severe potential is there so will go with that.
WEDNESDAY PM/ THURS AM - Strong storms Possible
What happens tonight will partially determine what happens on Wednesday night. The surface warm front is expected to be shoved south to the WI/IL border Wednesday morning. The low level warm front however should stay in southern Wisconsin becoming a focus for elevated storms Wednesday night as upper level support arrives. Still feel the peak of this event will be early Thursday morning, an unfavorable time for severe weather. In a similar status to tonight's t-storm event.
Discussion - Moisture improves but timing still unfavorable. Waiting to see what happens tonight.