High pressure centered north of the U.S./Canadian border with the southern edge of the cooler air slowly sinking south into northern Illinois Saturday night. The abundant sunshine and Pacific-origin air mass will boost temperatures to mid-November levels by Saturday afternoon – high across our area solidly in the lower 50s. However winds will shift east Saturday night enhancing the cooler air that will settle over the area Sunday.
Deepening low pressure will move east out of the central plains Sunday, the associated vanguard high and mid-level clouds spreading over our area adding to the features that will restrict warming during the day. While temperatures should reach at least the lower 40s away from the lake Sunday, the easterly winds off the cool waters of Lake Michigan will keep lakefront temperatures in the mid to upper 30s, impacting the Bears/Eagles at Soldier Field.
Clouds will continue to lower Sunday night with rain beginning early Monday and continuing through the day. Winds will become more southerly Monday, allowing temperature to warm back into the lower 50s.