FIRST THE FRIDAY WEATHER HEADLINES—-
CHICAGO — Beachgoers and mariners should be on the alert Saturday afternoon as a cold front could drop into the area, shifting winds and building waves on Lake Michigan.
Saturday’s weather will have kicked off beautifully through the morning into early and mid-afternoon — That’s when a cold front should hit — reaching the Illinois/Wisconsin line 2 to 3pm; the city 4 to 4pm and northwest Indiana from 6 to 7 pm
The front will introduce some rapid weather changes. First, it’s to usher gusty north/northeast winds into the area, replacing a SW flow which will have allow temps to surge into the mid 80s. The arrival of NNW winds gusting to 20-25 mph will drop temps from the 80s into mid-afternoon Saturday into the mid-60s to low-70s up and down the lakeshore, including downtown Chicago
Waves, which will have been negligible up to the frontal passage will begin building and could reach 4 to 6 feet by nightfall.
Of danger to swimmers will be the arrival of rip current in waters which will have been very calm up to that point
The front itself may lead to the development of scattered showers and a few t-storms which may increase in number and intensity as the front continues south across the metro area. T-storm coverage may fall in the 20 to 40% range from the city north–but increase to as much as 40-60% of the area in the southern suburbs.
The steady NE winds will continue Sunday producing rough waters for mariners and swimmer alike — but also limiting warming.
Rains turn off, though low 60-degree dewpoints indicate some post-front moisture is to linger behind the front Sunday and Monday (Labor Day)—some cloud cover is likely to persist, though the hope is breaks in the clouds will allow mixed sunshine
Current model keeps temps above normal through the majority of the coming 2 weeks — in other words, into mid-September.
HERE THE CHICAGO METRO FORECAST:
TONIGHT: Partly cloudy and warm with moderate humidities (dew point in the low to mid 60s). Low 68.
SATURDAY: Generous sunshine–just a scattering of clouds, warm and moderately humid into the afternoon. Then clouds build and some scattered showers and a few t-storms develop. Winds shift north/northeast and temps drop noticeably in the late afternoon and evening. High 86—but falling back to the 70s by nightfall–and to the mid 60s to low 70s along Lake Michigan. Thunderstorms may become more numerous south of the city late in the day and in the evening covering 40 to 60% of that area.
SATURDAY NIGHT: Mostly cloudy, breezy–especially along and over Lake Michigan and not as warm. Evening showers and t-storms gradually settle south and out of the area. Low 68.
SUNDAY: A good deal of cloudiness but with mixed sun interspersed. Breezy and cooler–but remaining a bit humid. High 75–but mid 60s to near 70 on area beaches.
LABOR DAY AND TUESDAY: Partly cloudy, seasonable temps. A bit breezy along Lake Michigan. High Monday 75; Tuesday’s high 78. Readings a bit cooler each day near Lake Michigan.
WEDNESDAY and THURSDAY: Sunshine filters through cloudiness at times. Some showers possible Thursday. Only minor day to day warming–but with easterly lake breezes continuing each afternoon along Lake Michigan. High Wednesday 79. Thursday’s high 80.
FRIDAY: A cloud/sun mix, more humid. Prospects for scattered showers, a few possibly thundery, increase in the afternoon and at night. High 82.