(9:45AM Saturday - 3/5/22) A storm system moving through the region will bring a severe t'storm risk and a period of high winds to portions of the state and region, this afternoon through Sunday morning.
A strengthening storm system will move from the Plains this morning, through the Midwest tonight, and then through the Great Lakes by Sunday morning. This storm system will bring a severe t'storm risk and a period of high winds to portions of the state and region, this afternoon through Sunday morning.
With this update we have slightly expanded the isolated (level 1) severe t'storm risk a bit further east across Northern and Central Illinois, and have also pulled the sporadic (level 2) severe t'storm risk eastward from Iowa and into portions of Northwest and Western Illinois. We have also increased high wind potential across Northeast Illinois for tonight through early Sunday morning, as confidence has grown in the potential for 50MPH+ wind gusts.
This Afternoon - Saturday Night, March 5-6th ~ High Wind Episode:
A strengthening storm system the region will bring a period of high winds to the state, this afternoon through Sunday morning. High winds aloft, characterized by a low level jet (850MB) of upwards to 50-70KT and 925MB winds of 40-55KT, will be in place. Adequate mixing is anticipated at least up to 925MB, along with strong warm air advection ahead of the storm system and cold air advection behind the storm system, which will aide in transporting higher winds to the surface. During this period, wind gusts of 35-50MPH are expected across much of the state, this afternoon through Sunday morning. There will also be a period of time from tonight through early Sunday morning that will feature the potential of 50MPH+ wind gusts across Northeast Illinois. Winds this afternoon into tonight will be southerly, winds from tonight through Sunday morning will be westerly.
This Afternoon - Saturday Night, March 5-6th ~ Severe T'Storm Episode:
The main risk for an isolated to sporadic (levels 1-2) severe t'storm risk will exist across portions of Northern and Central Illinois, this evening through later tonight. While a few isolated showers and t'storms have occurred this morning and will continue to be possible into this afternoon across portions of Northern and Central Illinois, the main focus will come later. A line or two of rain and t'storms will develop across Minnesota, Iowa and Missouri this afternoon, along and ahead of an advancing cold front. This activity is expected to sweep eastward across much of the state, this evening through early Sunday morning. Ahead of this activity, an environment will be in place supportive of some severe t'storm risk with this activity. This environment will feature low instability of up to 1,000J/KG, dew points in the mid 50's, good shear, good forcing, and good lapse rates of 6.0-8.0C. This environment will be supportive of upwards of an isolated to sporadic severe t'storm risk (levels 1-2) across portions of Northern and Central Illinois. Damaging winds, hail and an isolated tornado will be the severe weather threats.
Below are the severe t'storm and high wind forecasts for this event.