Temperatures Tuesday were once again stuck in the 30s under thick cloud cover, drizzle/light rain and fog. The rain has moved out but the cloud cover and fog will continue into Wednesday morning. Temperatures Wednesday will warm into the mid 40s, but warm even further as a strong low pressure system moves in from the southwest. Southerly winds ahead of the low Wednesday night into Thursday will hold temperatures in the low 40s through the morning, with highs Thursday reaching the low to mid 50s by early afternoon.
Unfortunately, the warm up will come with a chance for heavy rainfall overnight Wednesday into Thursday. Strong winds in the lower levels of the atmosphere will help transport a more ‘tropical’ air mass into northern Illinois and southern Wisconsin. Rain will be steady, and at times heavy, during the overnight. There could even be a few rumbles of thunder as well. Scattered showers continue through Thursday morning before coming to an end Thursday afternoon. A strong cold front will in from the northwest Thursday evening bringing temperatures down into the 20s Thursday night.
Rainfall amounts will range from around half an inch, up to three quarters of an inch across the Stateline. This will be the heaviest rainfall since October 26th when a little over an inch of rain fell.