Temperatures have been slow to warm the last few days as a slow moving low has kept quite a bit of cloud cover in place, as well as a persistent east/northeast wind. Monday was no different with an abundance of cloud cover and high temperatures warming only to the low to mid 70s. The average high for mid-July is mid 80s. Most of the heavier shower and storm activity has been focused to the south and southeast Monday; this is where there has been a little more sunshine and higher instability.
The clouds will hold thick Monday night as low pressure lifts north from southern Illinois. Atmospheric moisture will be plentiful and this will keep the chance for widely scattered showers and thunderstorms throughout the night/early Tuesday. Winds are expected to turn light as the low nears the Stateline which could cause some fog to develop by morning.
Tuesday will start off with a fair amount of cloud cover, and even a sprinkle/light shower or two, but as drier air arrives by the afternoon the cloud cover should begin to clear. Temperatures will be slow to warm initially due to the cloud cover, but should jump into the low 80s (more seasonable) late afternoon. Tuesday evening is shaping up to be a fairly nice night. The warming trend will continue midweek with highs reaching the mid and upper 80s Wednesday and Thursday.