Latest radar trends show a line of rapidly developing thunderstorms stretching form near Racine, Wisconsin southwest to near Mendota in north-central Illinois. The strongest thunderstorms appear to be in southern De Kalb County between Paw Paw and Sandwich. No severe weather has been reported with these storms so far, but they are capable of producing hail, strong winds and even a tornado.
Other thunderstorms are approaching the Waukegan area in Lake County, Illinois and will soon be moving out over Lake Michigan.
The Chicago area has been placed under a tornado watch that will officially be in effect until 2 a.m. Monday morning. However the storms are developing to the immediate west of the Chicago area and should clear the area well before the official expiration time.
So far, severe weather has been spotty with 3/4 inch hail reported in the Madison Wisconsin area. However, a strong cold front is approaching the city with very strong winds that shift rapidly with height creating a perfect environment for severe thunderstorms that can produce large hail, damaging winds and even tornadoes.
Thunderstorms are increasing rapidly in Lee County west of Shabbona and in DeKalb County. Another storm is developing in McHenry County.
Today’s burst of 80-degree warmth brings Chicago its highest temperatures in nearly two weeks, but it won’t last. A strong cold front — the leading edge of much cooler air — arrives late Sunday night, preceded by showers and thunderstorms that have the potential to produce strong and locally damaging winds. Temperatures crash after frontal passage and readings plunge into the lower 50s by daybreak Monday. The chilliest air of the newly-arrived autumn season dominates the area on Monday and Tuesday, and afternoon temperatures on both days will struggle to reach 60 degrees. Autumn’s first chilly outbreak is always an eye-opening reality check because we’re still acclimated to the warmth of summer, but it’ll be even worse this time: The chilly air arrives on gale-force winds that will gust above 40 mph on Monday. Mariners take note: Those winds are likely to generate towering 12-foot waves on Lake Michigan.
A bit of noise in the tropics
A poorly organized tropical depression has developed about 600 miles west of the Cape Verde Islands. It’s no threat to land, but the storm’s 35-mph winds may briefly strengthen to produce Tropical Storm Grace before the weakening and dissipating as it encounters cooler water and unfavorable upper winds.
In 1960 when I was in the Navy, our ship was in Chesapeake Bay and was caught in Hurricane Donna. I think it was a Category 5 storm? Can you provide details?
Hurricane Donna was a blockbuster storm that wreaked havoc on the entire East Coast and remains the only hurricane to produce hurricane force winds (74 mph or higher) from Florida to New England. At its peak intensity, Donna was indeed a Category 5 storm with top winds of 160 mph, but that was early on as it approached the Virgin Islands. When you encountered the storm on Sept. 12, 1960, it was a Category 2 storm with peak winds around 100 mph. However, much higher gusts were recorded offshore, at 138 mph on the Chesapeake Lightship located 17 miles off of Virginia Beach.
Chicago’s multiday run of hazy days, light winds and nighttime fog is coming to an end and a new pattern of active, changeable weather is beginning. It’s almost as if the city’s weather is taking a cue from the calendar, because the pattern change occurs with the transition from summer to autumn. Warmer air sweeps into the area this weekend, borne by gusty southwest winds that may send afternoon temperatures to 80 degrees on Sunday. But a surge of Canadian air follows quickly and Monday’s temperatures will struggle to reach 60 degrees. Powerful northwest winds gusting near 40 mph will add a real punch to the chill.
Thar she blows!
A whale of a storm is set to stir up Lake Michigan later this weekend. An intensifying low pressure system expected to pass just north of Lake Superior on Sunday will generate gale force winds (39 to 54 mph) across Lake Michigan. The Chicago National Weather Service has issued a gale watch for the entire lake from Sunday afternoon through Tuesday afternoon.