The return of wintry weather to the Chicago area was abrupt and unceremonious late Friday. One minute it was like spring, the next minute it was as if the clocks had been turned back to winter. Friday had been the year’s warmest to date before the powerful cold front hit. Highs reached 65 degrees at O’Hare, Midway and the lakefront, and soared to 68 at Buffalo Grove and 67 at Itasca. But the unseasonable warmth–with highs 20 degrees above historic mid-March norms here–proved no match for the onslaught of cold air.
While temperatures began dropping across the far northern suburbs as early as mid-afternoon, the city was invaded by 30+ mph gusts late in the evening rush hour, initiating a thermal tailspin. In a single hour’s time, readings at the Harrison-Dever Crib, three miles off Chicago’s shoreline, dove from 62 to 42-degrees–a 20-degree pullback–between 6 and 7 p.m. The same period saw readings at Northerly Island on the city’s lakefront plunge from 64 to 47 degrees. A minute-by-minute temperature analysis off a Weather Bug sensor on the South Side at the Dumas Elementary School indicated readings there plunged 15 degrees in only 12 minutes–from 62 degrees at 6:39 p.m. to 47 at 6:51. By late evening, North Shore readings were uniformly up to 25 degrees off the 60-degree levels of only hours before.
The pullback was hardly limited to Chicago. A huge swath of terrain well over a thousand miles across and extending from New Mexico, Utah and Arizona to the Great Lakes, registered 24-hour temperatures drops of as much as 40 degrees between Thursday and Friday. By late evening, snow was falling and piling up over sections of 14 states–with the heaviest totals still looming in the southern Plains and western Midwest.
By day’s end, Ouray, Colo., had a fresh 15.2″ cover of snow while Red River, N.M., had been buried beneath a foot of new snow and Vail, Colo., registered 11″. Snow intensity farther east was less spectacular with 2.6″ down in Fremont, 1.5″ in Polk City, Iowa, and a trace in Madison, Wis.
Blizzard in wake of Friday’s 72 could push Oklahoma City snow tally to all time record
A storm system, predicted to intensify over the southern Plains Saturday then drift east/northeast, may well spare Chicago’s its worst blow. But residents of Oklahoma City, where this season has already generated 20.7″ of snow–more than four times normal–may not be as lucky. With only 4.5″ separating the current seasonal tally from the city’s all-time record total of 25.2″ set in 1947-48, predictions of 4 to 10″ of snow may push the 2009-10 season to the all-time snowiest before this weekend ends.
Storms such as this weekend’s have, on occasion, been known to spin north to Chicago. But, models indicate the system is to close off then drift east/northeastward through Sunday and into Monday only swiping Chicago while producing its most prodigious rains and snows to the south and southwest. Areas of Kansas, Oklahoma, portions of western Missouri and northwest Arkansas are to sit at the epicenter of this storm’s heaviest snows.
Patches of cold rain and snow which extend into northern Illinois Saturday are likely to occur for the most part in above-freezing temperatures and over ground warmed by two days of 60s. That plus winds off Lake Michigan waters which are averaging 40 degrees should be enough to–barring an unexpected northward jog in the storm track–impede huge accumulations here.