Wednesday afternoon’s 11-degree increase over Tuesday just the start—atmospheric pattern undergoing huge changes which are to continue boosting temps—warming to be muzzled by easterly winds off 46-degree lake waters—shifting pattern to bring spells of wetter weather into the area Sunday and next week
Each of the coming 15-days is to post a temp surplus as North America’s upper air pattern undergoes a MAJOR CHANGE. The atmospheric blocking aloft is breaking down. This is allowing the Chicago area freedom from the dominance of a mammoth spring storm which crept across the area at a snail’s pace since last Friday.
TO DATE, May has posted an 8-degree deficit and is running 2.7-degrees cooler than the opening 3 days of the month a year ago.
PATTERN SHIFT BRINGS CHICAGO UNDER THE CONTROL OF THE SOUTHERN JET STREAM
That plus the development of blocking pattern as a huge dome of warm air develops over Canada next week means access to chilly air to our north is over for the forseable future.
At the same time, a more westerly flow aloft, something which is to continue through next week and beyond, is to send milder air into Midwest.
CHECK OUT THIS GOES WEST ANIMATION showing the streams of moisture onshore: https://rammb-slider.cira.colostate.edu/?sat=goes-18…
What chill DOES OCCUR in and around Chicago will be the product of winds off Lake Michigan’s 46-deg water–and that’s to happen due to easterly winds blowing ashore into lakeside areas.
WEEKEND TO BE 15-DEGREES MILDER THAN LAST (THOUGH WITH COOL LAKE BREEZES IN SHORELINE AREAS)—AND NEXT WEEK IS TO COME IN 12-DEGREE WARMER THAN THIS WEEK