Tue-Thur, April 27-29th Severe T'Storm Risk Update #1

(9:00PM - 4/27/21) Multiple disturbances will move through the region through Thursday, bringing a severe t'storm risk to much of the state tonight through Thursday morning.

Summary...
With a trough in place across the Western US, multiple disturbances will eject out into the Central US, moving through the region through Thursday. These disturbances will bring a severe t'storm risk to much of the state, tonight through Thursday morning. Model guidance and real time observations continue to support the going forecast, with little change needed.

​Forecast...
Tonight/Wednesday Morning...
A cold front expected to slide southward across Northern tonight, with a disturbance also expected to move through. Isolated to widely scattered showers and t'storms associated with this disturbance are possible across Northern and portions of Central Illinois tonight into Wednesday morning. An environment featuring instability of 1,500-3,000J/KG, dew points of 58-65, good forcing good shear and even mid level lapse rates around 6-8C is expected to be in place. Given the aforementioned environment expected, this will set the stage for an isolated (level 1) severe t'storm risk across Northern and portions of Central Illinois, tonight into early Wednesday morning. Hail will be the main threat.

Wednesday/Wednesday Night...
A frontal boundary is expected to be draped across Central and Southern Illinois on Wednesday, with multiple disturbances expected to move through. Several waves of showers and t'storms are expected to move across Central and Southern Illinois, Wednesday morning through Thursday morning. An environment featuring instability of 1,000-2,500J/KG, dew points of 64-71, good forcing good shear. Given the aforementioned environment expected, this will set the stage for an isolated (level 1) to widely scattered (level 2) severe t'storm risk across Central and Southern Illinois, Wednesday morning through Wednesday night. Hail and damaging winds will be the main threats.

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

JP