Sun-Mon, Aug 8-9th Severe T'Storm Episode Update #2

(11:30AM - 8/8/21) Several disturbances are expected to move through the region through Monday, bringing a severe t'storm potential to portions of the state this afternoon through Monday night.

Summary...
Several disturbances are expected to move across the Plains, Midwest and Great Lakes through Monday. These disturbances will bring severe t'storm potential to portions of the state, this afternoon through Monday night.

​Forecast...
​This Afternoon - Tonight, Aug 8th...
As a few disturbances move through the area, scattered showers and t'storms are expected to develop across portions of Iowa, Missouri and Northwest/Western Illinois this afternoon. This activity will likely congeal into one or more clusters, and will then spread northeastward across a large portion of the state this afternoon through tonight. An environment will be in place supportive of a severe t'storm risk with this activity. This environment will feature high instability of 2,500-4,500J/KG, dew points in the upper 60's to mid 70's, decent shear, decent forcing, and decent lapse rates of 5.5-7.5C. This environment will be supportive of upwards of an isolated to sporadic severe t'storm risk (levels 1-2) across portion much of the state. Damaging winds will be the main severe weather threat, with hail a secondary threat and an isolated tornado can't be ruled out.

Monday Morning - Monday Night, Aug 9th...
Areas of scattered showers and t'storms may be ongoing across portions of the state Monday morning. In the wake of this activity and as another disturbance moves through the area, scattered showers and t'storms are expected to develop across portions of Northern Illinois Monday afternoon. This activity will likely congeal into a cluster, and will then spread southeastward across portions of Northern and Central Illinois, Monday afternoon through Monday night. An environment will be in place supportive of a severe t'storm risk with this activity. This environment will feature high instability of 3,000-5,000J/KG, dew points in the upper 60's to upper 70's, decent shear, decent forcing, and modest lapse rates of 5.0-6.5C. This environment will be supportive of upwards of an isolated severe t'storm risk (level 1) across portions of Northern and Central Illinois. Damaging winds and hail will be the severe weather threats, though an isolated tornado can't be ruled out.

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

JP