Wednesday afternoon thunderstorms produce disappointing rainfall totals; city logs the smallest rainfall tally since July 1 in 80 years!



They sprang to life amid a third consecutive day of 90-degree late-season temperatures but produced disappointing rainfalls. Wednesday afternoon’s thunderstorms were selective in their rain and hail production. They did unleash 43 mph gusts at Lemont and Alsip. And large hail, which hit Bolingbrook, measured  1.75” in diameter while 1”-diameter hail pounded an area near Naperville and in Romeoville.



However, while Doppler-radar scans put the storms’ highest cloud tops at 45,000 ft., the heaviest rainfalls from them was disappointing to say the least. Preliminary Wednesday evening rainfall reports came in under a quarter-inch (0.23″) at Aurora and just 0.11” at Woodridge. Many areas, including O’Hare and Midway reported little more than a trace of rain.


With just 4.06” to its credit at O’Hare, the period since July 1 now ranks as the driest on record in 80 years, having seen under half (41%) its normal rain.



September’s opening 11 days running an eye-catching 6.5-deg above normal



Not only has it been dry, September temperatures to date are running quite warm, averaging an eye-catching 6.5-degrees above normal. That’s 3.1-degrees warmer than a year ago.



Strong cooling and full-fetch “NNE” winds to activate lake-effect rain showers by Thursday night



The NNE winds which sweep into Chicago later Thursday, Thursday night and Friday, are to churn Lake Michigan. Small craft advisories have been issued for the period. Building waves on the open lake are likely to keep many area mariners in their harbors.


Tropical forecasters monitoring Yucatan system which threatens sections of Mexico’s Gulf Coast with drenching rains in coming days


The “slow to start” to the 2013 hurricane season appears to be waning a bit.



A new disturbance near the Yucatan could become Tropical Storm Ingrid, unleashing potentially torrential rains on sections of the Mexican coastline in coming days. The system is being monitored closely!