Midwest windstorm impacts aviation

A major windstorm, stretching across some 2,200 miles, caused widespread flight delays and cancellations across the upper Midwest on Tuesday as it sped toward the northeast. Three general aviation airplanes were substantially damaged in a wind gust at DuPage Airport in West Chicago, Ill., ChicagoBreakingNews reported.

Damaged at DuPage were an Allegro light sport airplane, a Cessna 152, and a Piper Cherokee. One of the airplanes reportedly was tossed over an 8-foot-high chain link fence. Airport officials reported a 70-mph wind gust around the time the airplane made its unscheduled flight.

Countless GA flights were delayed or cancelled throughout the region. Airlines cancelled more than 500 flights Tuesday at Chicago O’Hare International Airport. Four-hour delays were reported at Minneapolis-St. Paul International/Wold-Chamberlain Airport, where 100 flights were cancelled. Delays and cancellations also were reported at Chicago Midway, Cincinnati, Indianapolis, and other airports.

Meteorologists focused on the weather system because of its massive size, combined with near record low barometric pressures. That low pressure—similar to the central pressure of a Category 3 hurricane—contributed to the storm’s high winds. The media reported gusts as high as 81 mph with the storm. (Category 3 hurricanes have sustained winds of 111 to 130 mph.)

“The mega-storm reached peak intensity late yesterday afternoon over Minnesota, resulting in the lowest barometric pressure readings ever recorded in the continental United States, except for from hurricanes and nor'easters affecting the Atlantic seaboard,” Dr. Jeff Masters wrote in his blog on Weather Underground. “So far, it appears the lowest reading (not yet official) was a pressure of 28.20 inches (954.9 mb) reduced to sea level reported from Bigfork, Minn., at 5:13 p.m. CDT.” The new record low barometric pressure set in International Falls, Minn., was almost half an inch lower than the previous record. Record low barometric pressures also were set in Duluth and in Superior, Wis., where the pressure of 28.36 inches set a new state record.

The storm ranks as the second-strongest cyclone to affect the Great Lakes, according to the National Weather Service’s Chicago office:

1. Great Ohio Blizzard, Jan. 26, 1978 (28.05 inches/950 mb)
2. Oct. 26, 2010, Superstorm (28.20 inches/955 mb)
3. Armistice Day Storm, Nov. 11, 1940 (28.55 inches/967 mb)
4. Anniversary Storm, Nov. 10, 1998 (28.55 inches/967 mb)
5. White Hurricane, Nov. 7-9, 1913 (28.60 inches/968 mb)
6. Edmund Fitzgerald Storm, Nov. 10, 1975 (28.95 inches/980 mb)

In its storm reports for Oct. 26, the National Weather Service’s Storm Prediction Center included preliminary reports of 26 tornados and 296 wind reports, including seven reports of winds or gusts of 65 knots or more. The report summary is available online.