Taking a cue from this week’s school year start-up in many suburban areas, the season’s first autumnal chill will arrive in Chicago today amidst gusty north winds and a cloud-filled sky. After one of the hottest summers in recent years, light jackets and sweaters will be in order tonight and early Tuesday as temperatures drop into the 50s. With a bit more sun, readings will rebound into the middle 70s Tuesday, and by the end of the week summer will be back in control with the mercury once again pushing the 90º mark.
While the record early season activity in the tropical Atlantic Basin has quieted down, and the area is currently storm free, Japan is bracing for a direct hit from Typhoon Mawar.
Passing near the island of Iwo Jima Sunday night, the typhoon is forecast to make landfall on the central Japan coastline between Osaka and Tokyo on Wednesday with winds as high as 140 m.p.h.

Welcome thunderstorms rolled through the entire rain-starved Chicago area early Saturday, but it was the north side that harvested most of the beneficial rainfall with many areas totaling between one and two inches. Officially, O’Hare measured 1.35 inches of rain, the largest one day rainfall there since last August 28 when 1.41 inches fell. Southern areas were not as fortunate with rainfall tallies sharply tapering off to less than one quarter inch. With drier air now moving into the area, it appears that the rain spigot will be turned off until at least the end of the week.
The next few days also promise to be quite cool having an autumnal-like feel to them, giving the city a preview of rapidly approaching meteorological fall which begins in less than two weeks on September 1. Daytime highs should remain in the 70s Monday and Tuesday, and aided by clear skies and lengthening darkness, overnight lows could approach 50º in the coolest inland suburbs.

Thundery downpours greet Chicagoans Saturday morning associated with a system which produced twisters Friday in Kansas and driving rains over sections of western Illinois. Totals north of St. Louis in McDonough County, Ill., reached 2.50” by nightfall Friday—much of it falling in only 30 minutes. An average of 24 computer projections indicates Chicago rainfall could reach 0.87”—but may range from as little as 0.75” in some areas to as much as 2” in others before winding down later Saturday.
More information is emerging on Thursday’s southern Wisconsin tornadoes. The deadliest of the nearly three dozen twisters—the Stoughton, Wis., storm—touched down at 6:05 p.m. Thursday and may have been on the ground 45 to 55 minutes, traveling very slowly by tornado standards—perhaps just 15 to 20 m.p.h., half a typical tornado’s forward speed. There has never been a stronger twister as far south in Wisconsin in August.