Hail and thundery downpours pelted the Plains late Wednesday and are heading for Chicago. The clouds responsible towered 10 miles above the terrain, and may be the first in a series to sweep the nation’s heartland in coming days. Rain won’t fall continuously. In fact, rain-free interludes are a good bet. But when the downpours do come, they may produce some impressive rainfalls here. Unfortunately, the clouds responsible threaten to obscure much of Thursday night’s annual Perseid’s Meteor shower.
Warm weather continued Wednesday. O’Hare’s 90° high was the 22nd of 2005. August’s opening 10 days rank third warmest since observations began at the site in 1959.
In contrast to Chicago’s recent heat, snow fell “down under” earlier this week. It’s winter in Australia—but snow isn’t common in Victoria or its state capital of Melbourne. The flakes there were the first since 1986 and the heaviest since 1951.

For the 30th time in 2005, temperatures at Midway Airport exceeded 90° Tuesday. The day’s high of 95° at both Midway and O’Hare—just 2 degrees shy of the 1913 record of 97°—tied as the city’s fourth warmest temperature to date. The warmest here has been 102° on July 24. An Aug. 9 hasn’t been warmer in 61 years—since a 97° high in 1944.
Tuesday’s heat pushes the average temperature at Midway Airport since June 1 to 77.4°, a reading 4.4 degrees above normal and advances the Meteorological Summer 2005 season to a ranking of 2nd warmest since 1928. Though heat relief is on the way, history strongly suggests Chicagoans haven’t seen the last of 90° temperatures. In previous comparably dry summers, an average of seven additional 90s have occurred beyond Aug. 10.
Every reporting station in the metro area reached or exceeded 90° Tuesday. Interestingly, the hottest area readings were at Rockford and Kenosha—both 97°.

Not since 1983 have the opening eight days of August failed to produce measurable rain at either of the city’s official weather observation sites. And while there are growing signs rain may appear on the scene over the coming week, Chicago’s rain deficit has grown to 10.12” since March 1. The dry weather’s impact has been devastating on the region’s corn crop. While some pockets of timely rainfall put some fields in better shape than others across northern and central Illinois, the latest USDA crop condition report rates 61% of Illinois’ corn crop in “poor” or “very poor” condition—the worst of any state in the Midwest.
Limited soil moisture contributed to low humidities amid Monday’s soaring Chicago readings. The area’s average daytime relative humidity of 54% was lower than the 69% average in perennially dry Phoenix, Ariz. The mercury climbed past 90° for the 29th time in 2005 at Midway (93°) and the 20th time at O’Hare (93°) Monday.