After a rather dry and quiet first week of September, strong, potentially severe, thunderstorms are expected in the Stateline on Sunday.
As of Saturday evening, clear skies over the Stateline wrap up a sunny and dry day in the Stateline. A few clouds are beginning to move in from the west out ahead of a storm system in the Plains. Thunderstorms are popping up in Southwestern Minnesota along the system’s warm front. These storms will expand through the evening as they propagate toward the Stateline. These thunderstorms will be widespread and rather strong, with the potential of becoming severe, by the time they reach Northern Illinois in the predawn hours of Sunday morning. The storms look to be in the area between approximately 5AM and 9AM followed by some isolated showers through the remainder of the morning. With these storms, heavy downpours and strong wind gusts are the primary concerns. Sizable hail is also very possible and lots of lightning is also expected. With how dry most grassy surfaces have gotten, heavy downpours could lead to a localized flash flooding potential. NOAA’s Storm Prediction Center has a slight risk, category 2 of 5, for severe weather in the Stateline on Sunday.
Through the afternoon, isolated showers may linger though most of the rainfall should go on a brief hiatus. Wind gusts will pick up through the afternoon, however, peaking as high as 40mph. Some clearing in the cloud cover is also possible in the afternoon. The amount of cloud cover through the morning and afternoon, as well as how long the morning rain lasts, will have a big influence on the severity of the thunderstorms in the evening. These storms will form along the same system’s cold font and should be a lot less widespread. A few showers and possibly some lighter thunderstorms in the midevening could precede a line of stronger thunderstorms in the latter part of the evening which is where the primary severe threat for tomorrow exists. The same concerns exist with these storms although this time a tornado or two cannot be ruled out. These storms should be rather short-lived and most, if not all, of the rain should be out of the area by midnight. By the end of the night, some areas of the Stateline could receive over an inch of rainfall. This will kick off a big cooldown in the Stateline with temperatures likely stuck in the lower 70’s the following day on Monday. High temperatures in the 60’s are expected for at least a few days in the upcoming week.