Sun-Thur, Aug 8-12th Severe T'Storm Event Recap

​(7:00PM - 8/13/21) A brief recap of the Sun-Thur, Aug 8-12th multi-day severe t'storm event that affected the state and region.

Recap Summary...
Multiple disturbances moved through the region, Sunday Aug 8th through Thursday Aug 12th. These disturbances aided in multiple days featuring widespread severe t'storms across the state and region, including several tornadoes and widespread damaging winds across Northern Illinois.

Daily Recaps...
​Sunday Afternoon - Sunday Night, Aug 8th...
A large complex of t'storms that originated across Missouri spread northeastward across a large portion of the state, Sunday afternoon into Sunday night. Isolated to sporadic t'storms were severe with this complex, producing damaging winds. A few additional clusters of rain and t'storms moved across portions of the state Sunday night into early Monday morning, however none of this activity was severe.

Monday Morning - Monday Night, Aug 9th...
A large complex of t'storms that originated across Iowa on Sunday night, spread eastward across Northern Illinois Monday morning. No severe weather occurred with this activity. Additionally, a complex of rain and t'storms developed across Central and Southern Illinois Sunday night, which pushed across Central and Southern Illinois through Monday morning. No severe weather occurred with this activity. The main focus was Monday afternoon into early Monday night, as several supercell t'storms developed and moved southeastward across Northern Illinois. Scattered activity was severe, producing several tornadoes, and a few instances of damaging winds and hail.

Tuesday Morning - Tuesday Night, Aug 10th...
A large complex of severe t'storms developed across Southwest Wisconsin and Eastern Iowa Tuesday afternoon. This complex of severe t'storms then quickly moved eastward across Southern Wisconsin and Northern Illinois Monday, later Tuesday afternoon into early Tuesday night. This complex produced scattered severe t'storms with widespread damaging winds, causing widespread tree damage and power outages across Northern Illinois.

Wednesday Morning - Wednesday Night, Aug 11th...
A complex of rain and t'storms developed across Northwest Missouri, Southeast Iowa and Western Illinois early Wednesday morning. This complex quickly moved northeastward across portions of Northern and Central Illinois Wednesday morning. This complex produced sporadic to scattered severe t'storms with widespread damaging winds, causing widespread tree damage and power outages across portions of Northern Illinois. An additional round of widespread rain and t'storms developed Wednesday evening into Wednesday night across portions of Northern and Central Illinois. Isolated to sporadic t'storms were severe with this activity, producing some instances of damaging winds and hail.

Thursday Morning - Thursday Night, Aug 12th...
A broken complex of rain and t'storms was ongoing and further develops across Southern Iowa, Northern Missouri and Central Illinois Thursday morning. This complex grew further upscale, then pushing southward across Central and Southern Illinois, Thursday morning through Thursday night. Isolated to sporadic t'storms were severe with this activity, producing some instances of damaging winds and hail.

Below are map representations of final forecasts for each day, as well as severe weather reports across the state and adjacent areas for each day. ​

JP