FIRST, THE WEATHER HEADLINES
–Friday becomes the first day of the past 11 to produce an above normal average temperature. Highs for the day are likely to hit 86-deg at O’Hare. If this occurs, that makes this the warmest day of the past 13.

–We’re on the precipice of some thundery downpours this weekend–the first could arrive in the city and metro area between 11pm and 2am tonight & Saturday morning.

–Weekend humidities are to surge after a week in a comfortable range. Dew points reach the mid to upper 60s Saturday and Sunday—a moderately humid range, but a good deal higher than the 40s and 50s we’ve seen most of the past work week.

–A cold, unstable pool of air is settling over the Chicago area aloft. This is to “destabilize” the atmosphere—–a fancy way of saying the new atmospheric set up is to encourage the warm, increasingly humid air which is on the way to ascend and cool–producing t-storms in the process.  They’ll come in waves starting later tonight but picking up Saturday– with soaking downpours when the heaviest of them pass across the area.

–Current modeling suggests while a few t-storms are to roam the area later Friday night into Sat morning—but the period to be on the lookout for more widespread and heavier thundery downpours appears to be in the 1pm to 10 pm Saturday time frame. This could present some issues at times for the Air and Water show.

–While rainfalls vary widely in warm weather months, it appears general rainfalls over the weekend may fall in the 0.3″ to 1.3″ range. With thunderstorms involved, a few heavier downpours topping 2″ can’t be ruled out.

–More scattered and less frequent showers are possible on Sunday.

–Temps move into the ABOVE NORMAL territory beginning mid and late next week through the following weekend. Day to day above normal temps could occur from Wednesday next week through Monday the following week—a marked change from the below normal temps we’ve recorded in Chicago the past 11 days.

HERE’S MY LATEST CHICAGO METRO FORECAST:

TONIGHT: Clouding over with scattered 40% coverage showers and thunderstorms which may first reach Chicago and many of its close-in suburbs in the 11 pm to 2am time range. Warm and becoming more humid. Low 69.

SATURDAY: Frequently cloudy, warm and moderately humid with several clusters of showers, some possibly thundery in the morning. More numerous and heavier thunderstorms, some with downpours sweep the area from time to time in the afternoon and evening. High Saturday 80.

SATURDAY NIGHT: Mainly cloudy, humid. Showers and thunderstorms, some capable of downpours, decrease in frequency late. Low 65.

SUNDAY: Some breaks for mixed sun, not quite as warm but remaining fairly humid. Scattered 40 to 50% coverage showers and possible thunderstorms–but with rain-free intervals between. High 77–lower 70s lakeshore.

MONDAY: Partly sunny, seasonably warm. Lake breezes reduce temps a bit along Lake Michigan. Only a slight chance of an isolated shower. High 79.

TUESDAY THROUGH WEDNESDAY: Mostly sunny days, scattered clouds at night with possible patchy ground fog in cooler locations. High Tuesday and Wed 85–but mid to upper 70s beaches.

THURSDAY and FRIDAY: Mixed sun and clouds, becoming more humid. Chance for scattered t-storms–most numerous Friday. Highs both days 84.