A slow-moving upper level storm system will inch across the area over the weekend into Monday. This will keep occasional rain and thunderstorms around during that entire period. Once the low moves south of the area on Saturday, the thunder chances will diminish and the temperatures will turn a lot cooler. A persistent northeasterly wind flow off the lake will limit temperatures, and some areas will not even break 60° on Sunday.
This slow-moving storm has the potential to accumulate a general 1 to 2" of rain by midday Monday. However, some isolated storms could produce an inch or more of rain per hour as they travel around 20 mph today.