Thur-Sun, June 24-27th Severe T'Storm Event Update #6

(10:00AM - 6/26/21) Multiple disturbances will move through the region through Sunday, bringing periods of severe t'storm potential to portions of the state through Sunday night.

Summary...
Multiple disturbances will eject out of the Plains, and push eastward across the Midwest and Great Lakes through Sunday. These disturbances will bring periods of severe t'storm potential to portions of the state, this through Sunday night. There period of daily severe t'storm threat now looks to extend into Sunday, and perhaps beyond as well. With this update, little to no change was needed for today's/tonight's forecast.

Forecast...
This Morning - Tonight...
Areas scattered showers and isolated t'storms have been ongoing this morning across Northern Illinois. Further south, clearing and destabilization is occurring, and another disturbance will be moving through the area. A new round of scattered showers and t'storms will develop by early this afternoon across portions of Central and Southwestern Illinois, spreading across a large portion of the state through tonight. The overall environment supportive of a severe t'storm threat will be in place across much of the state. This environment will feature moderate instability of 1,000-3,500J/KG, dew points in the mid 60's to mid 70's, decent shear, decent forcing, and  modest lapse rates of 5.0-6.0C. This environment will be supportive of upwards of an isolated to widely scattered (level 1-2) severe t'storm risk across a large portion of the state. Damaging winds, hail and an isolated tornado will all be severe weather risks.

Sunday Morning - Sunday Night...
Areas of isolated showers and t'storms may be ongoing across portions of Northern and Central Illinois Sunday morning. In the wake of this activity there will be clearing and destabilization, with another disturbance moving through the area. A new round of isolated to scattered showers and t'storms will develop Sunday afternoon across Central Illinois, spreading across a large portion of the state through Sunday night. The overall environment supportive of a severe t'storm threat will be in place across Central and Southern Illinois. This environment will feature moderate instability of 1,000-3,000J/KG, dew points in the mid 60's to mid 70's, decent shear, decent forcing, and  modest lapse rates of 5.0-6.0C. This environment will be supportive of upwards of a an isolated severe t'storm risk (level 1) across a large portion of the state. Damaging winds and hail will be the severe weather threats, though an isolated tornado can't be ruled out.

​Below is the severe t'storm forecasts for this event.

​Recap...
Thursday Morning - Thursday Night...
An initial complex of showers and t'storms spread across a large portion of the state Thursday morning into Thursday afternoon. Another large complex of showers and t'storms developed later Thursday afternoon and evening across Northeast Kansas, Southeast Nebraska, Southern Iowa, Northern Missouri and Central Illinois. This large complex then spread across much of the state, Thursday evening through Friday morning. Along the way, some severe t'storms occurred across portions of Western and Southwestern Illinois. Damaging winds, small hail and isolated tornadoes occurred with this activity.

Friday Morning - Friday Night...
An initial large complex of rain and t'storms spread across the state Friday morning. In the wake of this early activity, a new round of scattered showers and t'storms developed Friday afternoon and evening across Central Illinois, Missouri and Kansas. This activity then spread across much of Northern and Central Illinois, later Friday afternoon through Friday night. Some of this activity was severe across Central Illinois, producing damaging winds, large hail and a few tornadoes.

JP