(9:30PM - 4/6/20) Multiple disturbances will move through the region tonight through Wednesday, bringing a daily chance of severe t'storms to the state.
Scattered showers and isolated t'storms occurred across portions of Northern Illinois this afternoon and evening, near a warm front that lifted northward into Northern Illinois through the day. Tonight there will be a better focus for elevated scattered shower and t'storm development across Northern Illinois and vicinity. This activity will then continue to be possible overnight and into very early Tuesday morning, across portions of Northern and Eastern Illinois. A marginal environment will be in place, but will be enough to support a minimal severe t'storm threat across portions of Northern Illinois. Hail will the the main severe weather threat.
Tuesday morning-Tuesday night...
A few lingering showers and t'storms may be ongoing early Tuesday morning across portions of Northeast and Eastern Illinois, which will quickly clear the area by mid morning. In the wake of this early activity, clearing and destabilization is expected to occur ahead of the next approaching disturbance. Scattered showers and t'storms are expected to develop in the vicinity of a advancing cold front, across Wisconsin, Northern Illinois and Eastern Iowa. This activity will then sweep southeastward across Northern and Central Illinois, from Tuesday afternoon into early Tuesday night. Some activity is likely to back-build down into Missouri, which would likely push into Southern Illinois Tuesday evening into Tuesday night. It should be noted that there is some disagreement on extent of development with activity for Tuesday, and it will have to be monitored for changes in later updates. An environment featuring low to moderate instability, modest moisture, modest forcing and decent shear will be in place. This will help support a minimal to limited severe t'storm threat across much of the state. Large hail and damaging winds will be the main threats, though an isolated tornado cannot be ruled out.
Wednesday morning-Wednesday night...
Areas of showers and t'storms will be ongoing across Iowa and vicinity Wednesday morning into afternoon, associated with the next disturbance moving through the region. Additional scattered showers and t'storms are expected to develop in the vicinity of a advancing cold front, from Iowa down into Missouri Wednesday afternoon. This activity will then sweep southeastward across Central and Southern Illinois, from Wednesday afternoon into Wednesday night. An environment featuring low to moderate instability, modest moisture, good forcing and good shear will be in place. This will help support a minimal to limited severe t'storm threat across much of Central and Southern. Large hail and damaging winds will be the main threats, though an isolated tornado cannot be ruled out.
Below is the severe t'storm forecasts for tonight, Tuesday morning - Tuesday night and Wednesday morning - Wednesday night.
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