(9:30PM - 8/9/21) Several disturbances moving through the region through Tuesday will continue to bring severe t'storm potential to portions of the state, through Tuesday night.
Several disturbances will continue to move across the Plains, Midwest and Great Lakes through Tuesday. These disturbances will bring severe t'storm potential to portions of the state, through Tuesday night. With this update we updated the forecast for the remainder for tonight based on current trends, as well as upgraded the severe t'storm risk across portions of the state.
Tonight, Aug 9th...
Isolated to scattered showers and t'storms will continue to move southeastward across portions of Northern and Central Illinois tonight. An environment will continue to be in place supportive of a severe t'storm risk with this activity. 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, hail and an isolated tornado threat will eb the severe weather threats.
Tuesday Morning - Tuesday Night, Aug 10th...
A few areas of scattered showers and t'storms may be ongoing across portions of Eastern and Southern Illinois Tuesday morning. In the wake of this early activity, ample clearing and destabilization will occur across the state through the day. Additional widespread development of showers and t'storms is expected Tuesday afternoon across Wisconsin, Iowa and Missouri. This activity will likely congeal into multiple clusters, and will then spread eastward across much of the state, Tuesday afternoon through Tuesday night. An environment will be in place supportive of a severe t'storm risk with this activity. This environment will feature high instability of 3,500-5,500J/KG, dew points in the low to upper 70's, modest shear, decent forcing, and high lapse rates of 6.5-8.0C. This environment will be supportive of upwards of an isolated to sporadic severe t'storm risk (levels 1-2) across a large portion of the state. Damaging winds, hail and an isolated tornado threat will be the severe weather threats.
Below are the severe t'storm forecasts for this event.
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.