The first really decent temps of the season will arrive on Friday and last for part of the weekend, but there's a catch: Scattered showers and thunderstorms will be part of the deal. In looking over the latest rainfall models from the HPC, the heaviest rains will be aligned along the Ohio River as a cold front stalls out over the Tri-State. You can see in the accumulated rainfall map for Saturday night to Sunday night, we'll pick up around an inch of rain area wide.
Another surge of energy in the atmosphere will generate more rain to start the week on Monday, although the heaviest amounts will be to our east by that point as the cold front pushes toward the Appalachian Mountains. This map shows total rainfall in the Sunday night to Tuesday night time frame.
Finally, the 7-day precip map shows the grand total on rainfall from Thursday night to next Thursday night. Overall, 1-2" of rain will fall through this period, with the heaviest amounts concentrated over western Kentucky. River levels are elevated, so we'll have to monitor for possible flooding, although the rain is spread out enough, it shouldn't cause a rapid rise on any rivers.
No severe weather is on the horizon through the weekend, although some of the thunderstorms late Friday night may contain small hail due to the very cold air aloft over the region. This map from the Storm Prediction Center shows general thunderstorms across much of Illinois, Indiana and Ohio along the cold front.