It’s rained measurably during May a total of 1,060 times since weather records began here in 1871. But, in only 42 May storms during that period has rainfall reached or exceeded 1.80”. With a consensus of 14 computer model projections putting this storm’s rain near 1.84” by Friday’s close, it appears a 43rd is on the way. It’s rained comparably hard (or harder) only 375 times in 135 years, suggesting totals of that magnitude can be expected to occur an average of three times annually. The last time this much rain fell here was the 1.80” logged August 27-28, 2004.
The storm responsible for Thursday’s wind-driven downpours has intensified rapidly over the eastern Midwest overnight. Central air pressures have plummeted a stunning 20 mb—the equivalent of 0.60” of an inch of mercury. Barometer observers will appreciate such a drop—a change which is converting the system into a giant wind machine.
-Tom Skilling
WGN-TV Chief Meteorologist Tom Skilling and the WGN Weather Center staff provide daily coverage of weather in the Chicago area.
