Arctic air tightens grip on Chicago area; coldest night in 2 years possible as temps drop sub-zero amid stinging winds



Tuesday’s record 63-degree, April-level high—a reading more than 30-degrees ABOVE normal—is but a memory as Thursday dawns.  Frigid arctic air has reclaimed control over Midwestern weather and promises the Chicago area its coldest nighttime temperatures of the winter—and potentially the past two years—Thursday night.



The frigid blast to include sub-zero thermometer readings at many locations across the Chicago area and wind chills dipping to near 20-below by Friday morning. Daytime highs Friday also appear cold and may tie with the season’s coldest readings to date, moving no higher than the low teens.



Reedsburg, Wisconsin’s 10” tally tops Badger State’s snowfall reports; snow stacks up across northwest Illinois too, but only dusts the Chicago area.



The Midwest’s cover of snow was reinvigorated by Wednesday’s snowstorm to Chicago’s north and west. The system generated impressive accumulations from Iowa into northwest Illinois, Wisconsin and sections of Upper Michigan.  Totals as high as 10″ were reported at Reedsburg (northwest of Madison) and 9″ at Portage—both in Wisconsin. A 9 inch accumulation was also observed at Watson, Iowa. And, even northwest Illinois got in on the action.



Freeport reported a 4″ snowfall but amounts as high as 6.5″ fell at Scales Mound, 6″ at Dubuque and 5″ at Council Hill—communities west of Rockford in or adjacent to northwest Illinois.



8″ totals were reported by observers farther north at Fennimore, Platteville and DePere—all Wisconsin communities.


Far less impressive snow tallies came in from northeast  Illinois including the Chicago area.


Freeport, well to the Windy City’s northwest, was buried beneath a fresh 4.1″ snow cover, but amounts tapered as one moved east. Winnebago was home to a 2.1″ accumulation Wednesday while 2″ fell at Roscoe and 1.3″ at Rockford.



Immediate Chicago area totals included 0.6″ at Huntley and Downers Grove, 0.4″ O’Hare and 0.3” at Midway—though these measurements were taken late Wedsneday evening and don’t include any additional modest amounts which came down overnight.


Fresh cover of snow contributes to the chill


The new snow and the simultaneous re-emergence of a cross-polar jet stream—one able to draw Siberian air across the North Pole and into Canada, from which it spills into the Lower 48, are among the elements which are contributing to the strength of the new cold outbreak.



If predicted temperature trends verify, Chicagoans will see temps by Friday morning 66-degrees colder than Tuesday’s record-breaking, April-level 63-degree high. That would qualify as the largest four-day January temperature plunge on the books here since records began in 1871, easily surpassing the 61-degree four day decline which occurred here from January 31 through February 3, 1989.



“Lake snow machine” to produce lake-effect snows into  the western Michigan snow-belt; next Chicago snow systems due Friday night and Saturday


A new round of lake-effect snow is to produce sizeable accumulations in the western Michigan snow belt in coming days—as much as 10 or more inches at the hardest hit locations.



Chicago gets another shot at snow as early as late Friday night. Recent model projections estimate totals from that disturbance may fall in the 1 to 3-inch range.



Mammoth storm devastates parts of Georgia with deadly twisters while



Swarms of severe thunderstorms turned deadly Wednesday. Nearly 700-reports of severe weather, including damaging winds and large hail, were logged Tuesday and Wednesday by NOAA’s Storm Prediction Center (SPC). Dozens of reports of tornadoes were among the SPC severe weather reports.



Storm’s thundery downpours top 2″ over parts of the Chicago area and push January precip to 3.60″, twice normal and 14th wettest January of past 143 years



January has become the first month since last May to post a precipitation surplus here, in large part due to the thundery downpours which occurred Tuesday into Wednesday.



The month’s 3.60″ precipitation tally is more than twice the normal of 1.73″ and the wettest January to occur here in the Chicago area in 8 years. The area’s January precip total last year was only 1.86″.