(9:45PM Thursday - 3/17/22) A storm system will move through the region on Friday, bringing a severe t'storm risk across Southern Illinois Friday morning through Friday evening.
Little to no change was needed with this update, as the previous forecast is on track.
A storm system will track from the Southern Plains tonight, then into the mid-Mississippi Valley Friday afternoon, and eventually into the Southern Great Lakes Saturday morning. This storm system is expected to bring a severe t'storm risk to portions of the state and region on Friday.
Friday Morning - Friday Evening, March 18th ~ Severe T'Storm Event:
The main risk for an isolated to sporadic (levels 1-2) severe t'storm risk will exist across Southern Illinois, Friday morning through Friday evening. An initial round of rain and t'storms will spread across the state very late tonight on through Friday morning. As the main storm system moves through the region, a warm front will lift northward through the southern half of the state Friday morning, putting the southern half of the state in the warm sector and in an environment favorable for some severe t'storm risk. Scattered showers and t'storms are expected to develop from the area of low pressure on southward along an advancing cold front, across Eastern Missouri, Southern Illinois and Western Kentucky. This activity will then move northeastward across Southern Illinois, from late Friday morning through early Friday evening. The environment that will be in place will feature low instability of 500-2,000J/KG, dew points in the mid 50's to low 60's, good shear, good forcing, and good lapse rates of 6.5-8.5C. This environment will be supportive of upwards of an isolated to sporadic severe t'storm risk (levels 1-2) across Southern Illinois. Damaging winds, hail and an isolated tornado will be the severe weather threats.
Below is the severe t'storm forecast for this event.
-An isolated to sporadic (levels 1-2) severe t'storm threat across Southern Illinois, Friday morning through Friday evening.