(11:45AM - 12/5/21) A storm system moving through the region will bring severe t'storm and high wind potential to portions of the state, this evening through Monday afternoon.
A storm system will move from the Plains this morning, through the Midwest today and tonight, and then through the Great Lakes on Monday. This storm system will bring severe t'storm potential to Southern Illinois this evening and tonight and high wind potential to Northern and Central Illinois tonight through midday Monday.
Severe T'Storm Potential...
A cold front is expected to sweep across the state this afternoon through tonight. Ahead of this cold front, scattered showers and isolated t'storms will develop across Southern Missouri, Southern Illinois and Central Indiana this evening. This activity will then push eastward, affecting Southern Illinois this evening into early tonight. Ahead of this activity, the environment across Southern Illinois will be supportive of some severe t'storm threat. This environment will feature low instability of 250-1,250J/KG, dew points in the upper 50's to low 60's, good forcing, and lapse rates of 5.5-7.0C. This environment will be supportive of upwards of a level 1/isolated severe t'storm risk across Southern Illinois. Damaging winds, hail and isolated tornadoes will be the severe weather threats.
High Wind Potential...
A storm system moving through the region today through Monday will bring a period of high winds to portions of the state, this evening through Monday afternoon. High winds aloft, characterized by a low level jet of 40-50KT+ will be in place. As mixing will be near low level jet level, some of these strong winds aloft will be transported to the surface. Wind gusts of 30-45MPH+ will be likely this evening through Monday afternoon, across Northern and Central Illinois.
Below are the severe t'storm and high wind forecasts for this event.