Buckle up!  Chicago temperatures over the coming week are promising area residents quite a ride. From the unseasonable (and ill-timed) April-level chill with which the Memorial Day weekend opens Saturday and Sunday, to the heat of summer—likely to ride howling southerly winds into the area from Tuesday afternoon next week forward—area residents are in for what amounts to a ride through the temperatures of multiple seasons.

Clusters of showers and thunderstorms are to erupt along and to the north of the sharp thermal boundary between the two widely varied air masses.  Their trek across the Midwest makes it likely they will only brush areas from Chicago north while exposing far west and south suburbs to more significant rain tallies.

A corridor extending from Iowa east/southeastward into central Illinois and Indiana is likely to be on the receiving end of impressive rainfalls in the 1 to 4” range while far lighter amounts are to occur to the north.

A larger swath of the Chicago area gets in on precipitation later in the weekend as a northward shift in the well-defined boundary between unseasonably warm air to the south and unusually chilly air to the north takes place. Wider-coverage, frequently thundery clusters of storms may well reach Chicago and areas north later Sunday night into Monday (Memorial Day).  And additional thunderstorm-clusters are likely Monday night into Tuesday morning before shifting north, allowing rains to scatter and thin out here.

The 50s Thursday and Friday produced the coolest May 23-24 period in 26 years

Chicago’s official highs of 54 Thursday and 57 Friday marked the first time in 3 weeks readings that cool have occurred.  It’s the chilliest set of Mar 23 and 24 temperatures in 26 years.

Lakeshore communities shivered Friday through highs limited to the 40s

Though winds were a fraction of the near 50 mph peak velocities observed on Thursday, Friday afternoon’s east/northeasterly flow off Lake Michigan produced quite a chill in lakeshore areas.

Temperatures peaked no higher than the 40s at Kenilworth (48); Wilmette (48), Highland Park (48), Glencoe (48) and Northfield (49).

Hottest weather of 2013 to sweep in with warm front’s passage early Tuesday; series of 90-degree highs to follow mid and late week

Chicago’s weather is to undergo a sea change next week.  From Monday’s 69-degree Memorial Day high—a radical shift from the 95-degree reading which occurred on the holiday a year ago—temperatures are to surge into the mid 80s Tuesday and low 90s from Wednesday through Friday if current forecast trends hold up.  Temperatures at those levels would be the highest to date in 2013.