Travel-crippling, wind-driven snow, generated by this season’s most powerful storm to date, reduced visibilities to near zero Wednesday producing white-out conditions from eastern Colorado into Nebraska and Iowa. Roads there were closed and travel was described as impossible in many areas. The storm responsible is the same system producing Chicago’s drenching, sporadically lightning-infused rains Thursday.
The rains are only this sprawling storm’s opening salvo here. Plunging temperatures are to hit late Thursday in the western suburbs and extend into the city as winds build to 50 mph and higher in gusts Thursday night into Friday.
Hours of snowfall in the colder environment on the storm’s back side tonight are expected to deposit 2 to 6 inches of snow—and potentially more to the west and northwest. The high winds will send snow airborne which may seriously reduce visibilities while producing treacherously icy road conditions overnight.
System behind Chicago’s drenching rains the wettest here of the past 5 months; its precip is to equal all the moisture which has fallen the past 40 days
Were it merely the moisture sweeping the area Thursday, the storm would be welcome. This area is running incredibly dry. Chicago’s 2012 precipitation is off historic norms by 30% and running more than 10 inches below normal. A number of area rivers and lakes are near record lows, underscoring the critical nature of the partial moisture recharge this storm represents. But precipitation isn’t this storm’s only feature likely to impact the Chicago area. Wind, falling temperatures and snow are on the way and not likely to be welcome.
Rapid deterioration of Chicago’s weather hits late Thursday in west suburbs and Thursday night in city; high winds, falling temps and 6 to 10 hours of wind-driven snow combine to produce a nightmare scenario
The passage of a cold front mid and late- afternoon Thursday is to begin the rush of markedly colder air into the Chicago area. The strength of the incoming chill is challenging enough. But, even more worrisome is the arrival of an eye-catching backside wind field within which snow is to fall for as many as 6 to 10 hours. The blowing and drifting expected to occur and the fact standing water from the Thursday’s impressive waves of rainfall may well disrupt travel in open areas because of extremely limited visibilities and fast-forming ice.
Temps will be crashing to the teens and 20s by Friday morning while wind chills dive into to single digits—if not a bit below zero. Little temperature recovery is likely Friday over the freshly fallen snow.
Gusts could top 50 mph at times starting this evening for up to 8 consecutive hours and could exceed 40 mph well into Friday
It’s not every day a storm system is able to produce the kind of winds being predicted as the cold air hits Thursday night. The storm responsible is huge and its evolution will have to be monitored carefully.
New snows possible Monday (Christmas Eve); models hint at potential storm in Wednesday/Thursday time frame
Some light snow is predicted Monday. But it’s the system which follows toward Wednesday which may provide the more intriguing snowfall scenario.