The National Storm Prediction Center has included the entire Chicago area of northeast Illinois into northwest Indiana in the Enhanced Risk of Severe thunderstorms this Sunday afternoon and evening (tan-shaded area shown on the headlined map above). In addition to locally heavy downpours and vivid lightning, there will be a heightened risk in the strongest storms for large hail, damaging winds in excess of70 mph and even a few tornadoes. Note on the map above, all of our surrounding states will be under a severe weather threat today – extending west over all of Iowa and east into Pennsylvania. If you are planning outdoor activities or expect to travel, monitor the potentially explosive weather conditions and take appropriate precautions. The current Regional Weather Radar Mosaic is depicted below.
A large complex of strong t-storms will move ENE out of Iowa and northern Missouri this Sunday morning, the leading edge possibly reaching our area later this morning. As warm moisture-laden air sweeps into our area on the wings of SW winds, dew-points will rise into the 70s – this combining with the approach of a cold front from the NW, will cause the air mass overhead to become increasingly unstable. Lines of severe thunderstorms are likely over our area this afternoon into the evening hours, finally ending from NW to SE as the cold front moves through the area later this evening.