After several days of mild weather, temperature have begun to fall across the Chicago area as colder air arrives. A storm system from the southern Plains is expected to move northeast through the Ohio Valley tonight spreading a variety of precipitation across the area. The precipitation should begin as rain but transition to freezing rain, sleet and eventually snow as the colder air arrives and temperature drop below freezing not only at the surface but aloft. Areas north and west of Chicago should get mainly snow with a few inches of accumulation possible, while from the city south and east mixed bag of wintry precipitation could create hazardous travel conditions especially on untreated roads and walkways. If it possible that some winter-type precipitation advisories or warning will be issued for much of the Chicago Metro area later today or this evening. In the event that conditions worsen, the Chicago Weather Center Severe Weather blog will be activated to thoroughly cover the situation. WINNEBAGO-BOONE-MCHENRY-LAKE IL-OGLE-LEE-DE KALB-KANE-DUPAGE-COOK- LA SALLE-KENDALL-GRUNDY-WILL-LIVINGSTON- INCLUDING THE CITIES OF...ROCKFORD...BELVIDERE...WOODSTOCK... WAUKEGAN...OREGON...DIXON...DEKALB...AURORA...WHEATON...CHICAGO... OTTAWA...OSWEGO...MORRIS...JOLIET...PONTIAC 1247 PM CST SAT JAN 12 2013 ...WINTRY MIX INCLUDING LIGHT SNOW ACCUMULATION TONIGHT... TEMPERATURES CONTINUE TO FALL THIS AFTERNOON BEHIND A COLD FRONT...AND WILL LIKELY DROP BELOW FREEZING FROM WEST TO EAST THIS EVENING INTO THE EARLY OVERNIGHT HOURS. A STORM SYSTEM ORGANIZING SOUTH OF THE AREA TONIGHT WILL SPREAD PRECIPITATION NORTHWARD ACROSS THE AREA BETWEEN 7 AND 11 PM...WHICH WILL PERSIST THROUGH MUCH OF THE NIGHT. PRECIPITATION OVER THE NORTHERN CHICAGO SUBURBS AND WEST AND SOUTHWEST ACROSS NORTH CENTRAL ILLINOIS...INCLUDING ROCKFORD AND DIXON...WILL LIKELY BEGIN AS SNOW OR SLEET BEFORE CHANGING TO ALL SNOW. FARTHER SOUTH FROM CHICAGO SOUTHWEST ALONG THE INTERSTATE 55 CORRIDOR TOWARD PONTIAC...PRECIPITATION WILL BEGIN AS RAIN BEFORE TRANSITIONING TO SLEET IN THE EVENING AND THEN EVENTUALLY TO ALL SNOW OVERNIGHT. A TEMPORARY PERIOD OF FREEZING RAIN IS POSSIBLE DEPENDING ON HOW QUICKLY TEMPERATURES FALL. THE POTENTIAL EXISTS FOR SNOW AND SLEET TO BRIEFLY FALL HEAVILY AT TIMES...WHICH COMBINED WITH TEMPERATURES DROPPING BELOW FREEZING COULD RESULT IN TRAVEL BECOMING HAZARDOUS. MOST AREAS FROM CHICAGO WEST ACROSS NORTH CENTRAL ILLINOIS WILL EXPERIENCE SNOWFALL AMOUNTS OF 2 INCHES OR LESS. A LOCALIZED BAND OR TWO OF HEAVIER SNOWFALL AMOUNTS OF A FEW INCHES MAY OCCUR. A CHANCE OF LIGHT PRECIPITATION WILL LINGER INTO EARLY SUNDAY MORNING...WHICH INCLUDES A CHANCE OF FREEZING DRIZZLE WHICH COULD MAINTAIN ANY POOR ROAD CONDITIONS THAT DEVELOP. PERSONS PLANNING TRAVEL TONIGHT OR EARLY SUNDAY MORNING SHOULD MONITOR LATER FORECASTS ON THIS WINTRY PRECIPITATION EVENT AND BE PREPARED FOR ENCOUNTERING SLICK ROADS AS TONIGHT PROGRESSES.
ILZ023-033-039-INZ001-002-010-011-019-130430- KANKAKEE-IROQUOIS-FORD-LAKE IN-PORTER-NEWTON-JASPER-BENTON- INCLUDING THE CITIES OF...KANKAKEE...WATSEKA...PAXTON...GARY... VALPARAISO...MOROCCO...RENSSELAER...FOWLER 1247 PM CST SAT JAN 12 2013 /147 PM EST SAT JAN 12 2013/ ...WINTRY MIX DEVELOPING LATE TONIGHT... TEMPERATURES ARE BEGINNING TO FALL ACROSS THE REGION EARLY THIS AFTERNOON AS A COLD FRONT PUSHES EAST...AND WILL LIKELY FALL TO OR BELOW FREEZING BY LATE EVENING. A STORM SYSTEM ORGANIZING TO THE SOUTH OF THE AREA WILL SPREAD RAIN...OR A MIX OF RAIN AND SLEET ACROSS EAST CENTRAL ILLINOIS AND NORTHWEST INDIANA BETWEEN 6 AND 9 PM WHICH WILL THEN PERSIST THROUGH THE EVENING. PRECIPITATION WILL TRANSITION TO A MIX WITH SLEET AND POSSIBLY SNOW OVERNIGHT ACROSS KANKAKEE...GIBSON CITY...AND INTO NORTHWEST INDIANA. IF THIS TRANSITION WERE TO OCCUR EARLIER...FREEZING RAIN WILL BE POSSIBLE INCLUDING MINOR ICE ACCUMULATIONS AS THE PRECIPITATION MAY BE MODERATE TO HEAVY AT TIMES. SNOW ACCUMULATIONS ARE EXPECTED TO BE ONE HALF INCH OR LESS. A CHANCE OF LIGHT PRECIPITATION WILL LINGER INTO SUNDAY MORNING... WHICH INCLUDES A CHANCE OF FREEZING DRIZZLE WHICH COULD MAINTAIN ANY POOR ROAD CONDITIONS THAT DEVELOP. PERSONS PLANNING TRAVEL LATE TONIGHT OR EARLY SUNDAY MORNING SHOULD MONITOR LATER FORECASTS ON THIS WINTRY PRECIPITATION EVENT AND BE PREPARED FOR ENCOUNTERING SLICK ROADS AS TONIGHT PROGRESSES.
