Chicagoans came off the first weekend of August—a weekend which was  cooler than normal and sporadically wet in the city with drenching rains soaking southern sections of the metro area where as much as 4 to 6″ of rain was reported Friday night into Saturday—into a Monday which opened cloud but saw breaks in the clouds allow patches of blue sky and some mixed sunshine by and during the afternoon. 

Monday will go into the books with a high of 79 and a low of 67—which average out 2.4-deg below normal. It’s the 3rd consecutive day to post a daily average temp deficit.  Still. last week finished nearly a degree ABOVE NORMAL—this week is likely to post a 0.4-deg temp surplus with next week likely to approach a degree above normal. (NOTE: There has been a “cool bias” in recent official 6 to 10 and 8 to 14 day temp projections—a trend which seem likely to continue based on the latest forecasts and our in house model work).

It’s worth noting August’s opening 7 days are off to a cooler start than a year ago. We had logged  THREE DAYS above 90 by this time last August; there’s only been one this August to date. But there could be several days in the next two weeks in which Chicago temps approach  if not reach 90 over at least sections of the metro area —including later this week (Friday)–and Tuesday, Friday, Sunday and Monday of the week which follows is current forecast trends verify.

A near to above normal precip trend appears likely to dominate overall the next two weeks in Chicago and areas close-by—though as this weekend’s precip trend show, warm season rainfalls are capricious—producing flooding downpours in one area while missing another all together. 

The atmosphere is to be moderately “understable” tomorrow—which means a few showers and t-storms may “bubble up” in the day’s warner hours.  Beyond that, a “wave” is to sweep across the area increasing shower and t-storm prospects Wednesday afternoon and night—and still another system may increase shower and t-storm prospects Friday afternoon and night.  One more system could traverse the area early next week. So rain prospects are hardly “zero” this week.

The weekend came in close to 4-deg cooler than last and generated virtually NO precip of significance north of the city and just 0.13″ at O’Hare.  But weekend rain tallies increased as one traveled south with Midwest picking up 0.67″.

While Saturday saw just 16% of its possible sun and Sunday came in with just 14% of its possible sun—Monday was modestly better, hosting 47% of its possible sunshine.

Happily, there’s been a  MODEST  improvement in the MOLD AND WEED POLLEN counts from Loyola Medicine Monday—with MOLD coming in “MODERATE” and WEEDS coming in “LOW”.  Both were MODERATE TO HIGH last week.


TONIGHT: Clouds scatter and diminish, seasonable early August overnight warmth. Patchy ground possible as winds, especially cooler surrounding areas. Low 67—but some low 60s inland.

TUESDAY: Sunshine mixes with cottony summertime cumulus as temps warm. Moderate humidities. Several scattered afternoon and evening showers and t-storms possible impacting 20 to 30% of the area. High 86.

TUESDAY NIGHT: Showers diminish then clouds scatter again. Warm. Patchy ground fog—especially cooler areas surrounding the city and close-in suburbs. Low 68—with  low 60s inland.

WEDNESDAY: Clouding over, warm. Growing prospects for afternoon and evening showers and t-storms in 30 to 50% of the area. High 84.

THURSDAY: A good deal of sunshine—just some summertime fair weather clouds. Lake breezes reduce shoreline temps over their inland counterparts.  High 85—but mid 70s to 80 beaches.

FRIDAY: Increasing cloudiness. Chance of afternoon and nighttime showers and t-storms again. Quite warm and more humid. High 89

SATURDAY: Generous sunshine, warm but not as humid. High 82—70s beaches.

SUNDAY: Sun amid building clouds. An isolated afternoon shower or t-storm or two possible High 84—70s beaches.

MONDAY: More clouds. Some showers and t-storms possible. High 79.