A fast-moving clipper system is expected to move southeast across the Midwest tonight on a track south of Chicago and is expected to deliver a significant snowfall in the 2 to 5 inch range, with the heaviest amounts across the north portions of the Chicago Metro area, mainly north and east of a line from Rockford to Valparaiso The snow will taper off sharply to the south where only minor amounts are expected. With temperatures well below freezing the snow will quickly accumulate and cover roads making for hazardous travel. The snow will restrict visibilities which will drop to 1/2 mile or less in the areas of heaviest snowfall. The snow should begin late this evening between 9pm and midnight and end later Monday morning. The snow is expected to significantly impact the Monday morning commute. As the system snow winds down Mnday morning additional lake-effect snow is possible in lakeside counties.
The purple shaded counties are covered by the winter weather advisory.
...ACCUMULATING SNOW TO DEVELOP LATE THIS EVENING AND CONTINUE THROUGH MONDAY MORNING...
The Chicago National Weather Service Office has issued a Snow Advisory for a good portion north-central and northeast Illinois and northwest Indiana from 10PM this Sunday evening until noon in Illinois and 6PM in the evening in Indiana. Below are the National Weather ssevice issuances:
NATIONAL WEATHER SERVICE CHICAGO IL
1213 PM CST SUN FEB 3 2013
...ACCUMULATING SNOW TO DEVELOP LATE THIS EVENING AND CONTINUE
THROUGH MONDAY MORNING...
.A WELL ORGANIZED CLIPPER TYPE SYSTEM WILL BRING SNOW TO NORTH-
CENTRAL AND NORTHEAST ILLINOIS AND FAR NORTHWEST INDIANA LATE THIS
EVENING THROUGH MUCH OF MONDAY. THE HIGHEST SNOWFALL TOTALS ARE
EXPECTED TO RANGE FROM 3 TO 5 INCHES ALONG AND NORTH OF A LINE
FROM JUST NORTH OF ROCKFORD TO CHICAGO TO VALPARAISO. THERE MAY BE
A FAIRLY SHARP CUTOFF IN SNOW AMOUNTS OF GREATER THAN 3 INCHES
SOUTH OF THIS LINE. THERE IS SOME POTENTIAL FOR LOCALLY HIGHER
AMOUNTS GIVEN THAT LAKE ENHANCEMENT OF SNOWFALL IS POSSIBLE LATE
MONDAY MORNING INTO THE AFTERNOON FROM COOK COUNTY TO LAKE AND
PORTER COUNTY IN INDIANA.
...WINTER WEATHER ADVISORY IN EFFECT FROM 10 PM THIS EVENING TO
NOON CST MONDAY...WINNEBAGO-BOONE-MCHENRY-LAKE IL-KANE-DUPAGE-COOK-
AND LAKE AND PORTER COUNTIES INDIANA
INCLUDING THE CITIES OF...ROCKFORD...BELVIDERE...WOODSTOCK...
THE NATIONAL WEATHER SERVICE IN CHICAGO HAS ISSUED A WINTER
WEATHER ADVISORY FOR SNOW...WHICH IS IN EFFECT FROM 10 PM THIS
EVENING TO NOON CST MONDAY.
* TIMING...SNOW WILL BEGIN LATE THIS EVENING AND DIMINISH TOWARD
MIDDAY MONDAY...THOUGH LIGHT SNOW SHOWERS MAY LINGER THROUGH
* ACCUMULATION...2 TO 5 INCHES WITH THE HIGHEST AMOUNTS EXPECTED
ALONG AND NORTH OF A ROCKFORD TO CHICAGO LINE. LOCALIZED
SLIGHTLY HIGHER AMOUNTS ARE POSSIBLE ACROSS COOK COUNTY IF LAKE
ENHANCEMENT CAN OCCUR LATE MONDAY MORNING.
* MAIN IMPACT...SNOWFALL RATES OF UP TO ONE INCH PER HOUR MAY
OCCUR AT TIMES LEADING TO RAPID SNOW ACCUMULATION ON ROADWAYS.
THE HEAVIEST INTENSITY IS EXPECTED FROM APPROXIMATELY 11 PM TO 4
AM FROM THE ROCKFORD TO MARENGO AREAS AND BETWEEN APPROXIMATELY
3 AM AND 8 AM FOR CENTRAL AND NORTHERN AREAS OF THE CHICAGO
NATIONAL WEATHER SERVICE NORTHERN INDIANA...
LAKE EFFECT SNOW WATCH REMAINS IN EFFECT FROM 11 PM CST SUNDAY THROUGH
MONDAY EVENING...FOR LA PORTE COUNTY-
INCLUDING THE CITIES OF...MICHIGAN CITY...LA PORTE
A STORM SYSTEM IS EXPECTED TO TRACK THROUGH THE OHIO VALLEY ON
MONDAY. SNOW WILL REDEVELOP AFTER MIDNIGHT TONIGHT AND CONTINUE
INTO MONDAY NIGHT. ADDITIONAL SNOW ACCUMULATION IN EXCESS OF 8
INCHES IS POSSIBLE LATE TONIGHT THROUGH MONDAY EVENING.