Story Summary

Wintry weather may dampen holiday weekend travel

Kicking off the holiday weekend, Friday was a messy day on the roads, especially in some parts of the Chicago area, where freezing rain and drizzle continues to fall.

It could be the start of a major storm system that could drop a significant amount of snow and sleet during the weekend before Christmas.

 

Story Timeline
Previous Next
This story has 8 updates

A Winter Storm Warning is in effect for Winnebago, Boone, McHenry, Ogle, Lee, DeKalb Counties tonight into Sunday – calling for freezing rain or sleet this evening changing over to wet snow later tonight and continuing in a diminishing form Sunday. Snowfall totals of 4 to 8-inches expected with heaviest amounts north of a Dixon-Woodstock line and lesser amount south and east of that line.

A Winter Weather Advisory is in effect this evening for LaSalle, Grundy, Will, Du Page, and Cook Counties calling for rain/freezing rain/ and possibly sleet – becoming all rain and then eventually changing over to snow Sunday morning before ending later in the day. Kane and lake Counties are included in this same Winter Weather Advisory this evening, but  also the reminder of the night into Sunday morning as rain may change over to accumulating snow 2 to 4 inches before ending later Sunday.

A Flood Warning is in effect this evening for Benton, Jasper, and Newton Counties in Indiana and Iroquois, Ford and portions of Livingston and Kankakee Counties in Illinois as additional heavy rains could cause flooding problems in small stream and ponding of susceptible areas.

FOR UPDATES LOG ON TO CHICAGO WEATHER CENTER

Far and away, the heaviest snow with the incoming storm–in spots more than 8″ and possibly 10″ of it–is to fall from eastern Iowa and northwest Illinois northward into Wisconsin.

FOR MORE LOG ON TO THE WEATHER CENTER BLOG

The Chicago area is under a freezing rain advisory until 3 p.m. Friday.

That’s bad timing for anyone hoping to fly out of Midway or O’Hare airport.

Forecasters are also warning drivers to be especially cautious.  Even people who walking are advised to take it easy.

Streets and sidewalks have been icing up as the rain hits the roads and temperature drops below freezing.

LATEST TRAFFIC UPDATES

LATEST WEATHER UPDATES

Rain and freezing rain will be possible through much of the day as temperatures hover near the freezing mark.

McHenry, Lake, De Kalb and Kane counties are under a Freezing Rain Advisory until 3 p.m. as a layer of ice on local roadways is possible.

freezingrainadvisory12-20The Chicago metro and points south should mainly see light rain today as temps hover in the low to mid-30s, but locations outside the advisory area have the chance to see some ice as temperatures could dip close 32 degrees late in the day.

As we fall to near 30 degrees tonight some drizzle could lead to slick spots in southern counties late in the overnight.

A winter storm headed toward the Midwest could lead to a wintry mix and accumulating snow Saturday into Sunday.

FOR THE LATEST UPDATES GO TO CHICAGO WEATHER CENTER

By Tom Skilling

Rain’s fallen into sub-freezing air across the northern suburbs overnight. The result has been” glazing”—a process which leads to the build-up of ice on untreated outdoor surfaces.

The icy conditions extend north from counties bordering Wisconsin into the Badger State itself.

Clouds and sporadic light rain and drizzle are to extend into Friday producing what promises to be a damp, raw day with temperatures close to historic norms.

To have “near normal” temps is quite an accomplishment in a month running nearly 6-degrees below normal and 17-degrees colder than a year ago!

The icy far north suburban locations follow the area’s highest daytime temperatures in 2 weeks 

The ice follows the Chicago area’s mildest temperatures in 2 weeks Thursday.  Residents near Midway Airport reveled in low 40-degree temperatures, a daytime high which was nearly 10-degrees above normal.

Thursday’s 39 and 33-degree extremes at O’Hare produced an above normal temperature for they first time in over two weeks.

A more significant winter storm threatens heavy, possibly flooding rains south and accumulating snow here and north Saturday night into early Sunday

Winter storm and flood watches have been posted for sections of the Chicago area for the coming weekend in anticipation of a potent weather system expected to lift from Texas into Indiana. That’s a track forecasters take quite seriously because it’s been known to bring the region heavy snow.

The more than inch of rain expected to fall on the area’s significant snowpack plus the potential for milder temperatures to contribute to the break-up of ice on area rivers, is to increase the potential for flooding late Saturday and Saturday night, particularly in southern sections of the metro area.

When ice breaks up on area rivers, it can lead to dams of accumulated ice on rivers behind which water accumulates.

A predicted transition to snow has been accelerated by overnight computer model runs. This means it could be snowing in the city by late Saturday night, around the time the northeast-bound storm is generating the maximum upward vertical motion in the area. It’s a set-up which may lead to heavy snowfall—even isolated thundersnow.

This further suggests sections of the Chicago area will register a significant accumulation of snow by daybreak Sunday. Snowfall then tappers off and frigid arctic air stages a come-back which sets Sunday’s temperatures on a downward spiral to single-digits Sunday night.

The arctic chill is to produce a cold open to Christmas week.

FOR THE LATEST GO TO CHICAGO WEATHER CENTER

Weather
12/19/13

Wet and cold weekend ahead

Chicagoans welcome more moderate temperatures while casting a nervous eye toward a California storm expected to roll into the Midwest later Saturday and Saturday night—then linger into Sunday

The area’s short-term weather concerns revolve around a disturbance which arrives later Thursday and produces drizzle predicted to build into steadier rain Thursday night.

Storm threatens snow, flooding rains and severe weather over nation’s mid-section; arctic chill to send temps plunging later Sunday into Monday

The stronger weekend storm system is to follow late Thursday’s disturbance into the Chicago area amid strengthening easterly winds Friday and Saturday. The system  is a moist one. Rainfall is to begin  later Saturday and Saturday night  on top of a 3 to 6” snowpack. The rain may become an issue—particularly in the area south of I-80. That’s because the top layer of soil has frozen in the abnormally cold pattern which has dominated much of December. The frozen layer of top-soil prevents percolation of moisture into the soil. This produces “run-off” which winds up in area rivers, many of which are extensively frozen. Any break-up of the ice there may produce ice jams which can produce or aggravate flooding.

For more log on to Chicago Weather Center

Chicago’s morning weather forecast

Weather
12/19/13

Winter storm possible this weekend

Chicago’s uninterrupted 13-day string of below normal temps ends Wednesday with the arrival of the area’s mildest daytime high of the past 12 days.Temps are to peak at 36—a reading which would be substantially higher were it not for the snowpack in place here.

In a month dominated by arctic air, with an average December temperature more than 7-degrees below normal, ANY reprieve from the chill is welcome.

All by themselves, the past 13 days here have averaged more than 11-degrees below normal.

Gulf moisture is northbound and its arrival Wednesday night is to produce clouds followed by haze, some light fog and, eventually, some drizzle and patches of light rain as moisture levels increase over the coming 36 hours.

North toward Wisconsin, it’s possible some snow or ice pellets will occur Thursday night into Friday. A dusting to as much as an inch and a half of snow is possible there during that time frame.

Weekend storm potential being monitored Saturday night into Sunday; many questions in place at this early stage

Forecasters—this one included—continue reviewing model forecasts of a potential winter storm this weekend. The Saturday night/Sunday period appears most at risk from the weather system which is predicted to lift from Texas into the Ohio Valley between Friday and Sunday morning. It’s potentially a troublesome track for Chicago—one which, in the past, has been a snow producer here.

Complicating any forecast of this storm’s future behavior is the thermal structure of the atmosphere predicted for this weekend. While Chicago is to sit beneath the axis of this system’s most prolific precipitation, the form that moisture is to take will be driven by the temperatures within which it’s occurring. A more precise determination of just how temperatures will lay out this weekend is to come in the days ahead.  Until then, those with travel plans would be well advised to monitor future forecasts.

FOR MORE LOG ON TO CHICAGO WEATHER CENTER

Advertisement