Alert archive / Illinois / Winter Storm Warnings in 2012

Winter Storm Warning 2, NWS Chicago, IL

January 19, 20129 counties in Illinois

NWS Chicago, IL issued this winter storm warning at Jan 19, 2012, 9:26 PM CST for 9 counties in Illinois. It took effect at Jan 20, 2012, 6:00 AM CST. It was in force for 15 hr. 60 reports came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued
Jan 19, 2012, 9:26 PM CST (03:26 UTC)
In effect from
Jan 20, 2012, 6:00 AM CST
Expired
Jan 20, 2012, 8:56 PM CST
In force
15 hr
Issued by
NWS Chicago, IL

Counties Boone County, IL, DeKalb County, IL, DuPage County, IL, Kane County, IL, Lake County, IL, Lee County, IL, McHenry County, IL, Ogle County, IL, Winnebago County, IL

The radar

The Chicago radar (KLOT), 74 km from the middle of the area, began a volume at 03:27 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

What was reported inside it

TimeReportWhereRemark
Jan 20, 11:14 AM CSTSNOW 0.7Winnebago, ILTAKEN AT WREX TV
Jan 20, 11:14 AM CSTSNOW 0.8Oregon, ILRELAYED BY WREX TV.
Jan 20, 11:30 AM CSTSNOW 0.1Dupage Airport, ILSTORM TOTAL AS OF 1130 AM.
Jan 20, 11:30 AM CSTSNOW 0.8Mount Morris, ILSNOW BEGAN 0925
Jan 20, 11:55 AM CSTSNOW 0.8Rockford, ILAT WTVO-TV...MODERATE SNOWFALL OCCURING
Jan 20, 12:00 PM CSTSNOW 0.4Rockford Airport, ILSTORM TOTAL AS OF NOON.
Jan 20, 12:05 PM CSTSNOW 1.5Amboy, ILESTIMATED STORM TOTAL SO FAR. ROADS SNOW COVERED. 1/2 MILE VISIBILITY IN MODERATE TO HEAVY SNOW AT TIME OF REPORT.
Jan 20, 12:08 PM CSTSNOW 1.5Amboy, ILESTIMATED STORM TOTAL SO FAR. 1/2 TO 3/4 MILE VISIBILITY IN MODERATE SNOW AT TIME OF REPORT.
Jan 20, 12:09 PM CSTSNOW 1Elburn, ILCURRENTLY EXPERIENCING HEAVY SNOW WITH ONE HALF MILE VISIBILITY.
Jan 20, 12:23 PM CSTSNOW 1De Kalb, ILESTIMATED STORM TOTAL SO FAR. MODERATE TO HEAVY SNOWFALL AT TIME OF REPORT...WITH 1/2 MILE VISIBILITY.
Jan 20, 12:27 PM CSTSNOW 1Crystal Lake, ILESTIMATED STORM TOTAL SO FAR. MODERATE SNOW AT TIME OF REPORT.
Jan 20, 12:30 PM CSTSNOW 0.3Vernon Hills, ILESTIMATED STORM TOTAL SO FAR. SNOW INCREASING IN INTENSITY AT TIME OF REPORT.
Jan 20, 12:45 PM CSTSNOW 2Rochelle, ILSTORM TOTAL SO FAR.
Jan 20, 12:52 PM CSTSNOW 0.5Lombard, ILESTIMATED STORM TOTAL SO FAR. VISIBILITY HAS BECOME QUITE LOW IN THE PAST HOUR.
Jan 20, 1:00 PM CSTSNOW 0.5Downers Grove, ILSTORM TOTAL SO FAR AT FAIRVIEW AND OGDEN AVENUE.
Jan 20, 1:00 PM CSTSNOW 0.81 Sse Richmond, ILTOTAL SO FAR - BUT MODERATE SNOW IS NOW INCREASING TO HEAVY SNOWFALL.
Jan 20, 1:00 PM CSTSNOW 1Rockford Airport, ILHEAVY SNOWFALL AT ROCKFORD AIRPORT. 1 INCH MEASURED BETWEEN 1200 PM AND 100 PM.
Jan 20, 1:10 PM CSTSNOW 12 Se Aurora, ILSTORM TOTAL SO FAR NEAR RUSH COPLEY MEDICAL CENTER.
Jan 20, 1:10 PM CSTSNOW 2Belvidere, ILSTORM TOTAL SO FAR. RELAYED BY WREX.
Jan 20, 1:15 PM CSTSNOW 0.6Aurora, ILSNOWFALL IN 1 1/2 HOURS.
Jan 20, 1:15 PM CSTSNOW 0.9Fox Lake, ILSTORM TOTAL SO FAR.
Jan 20, 1:15 PM CSTSNOW 2Lincolnshire, ILSTORM TOTAL SO FAR.
Jan 20, 1:20 PM CSTSNOW 2Loves Park, ILSTORM TOTAL SO FAR. RELAYED BY WREX.
Jan 20, 1:26 PM CSTSNOW 1.5Marengo, ILSTORM TOTAL SO FAR. RELAYED BY WTVO.
Jan 20, 1:30 PM CSTSNOW 1.32 Wsw Elk Grove Village, ILSTORM TOTAL SO FAR. STEADY LIGHT TO MODERATE SNOW AT TIME OF REPORT.
Jan 20, 1:30 PM CSTSNOW 1.33 Se Aurora, ILSTORM TOTAL SO FAR.
Jan 20, 1:30 PM CSTSNOW 1.5Cary, ILSTORM TOTAL WITH 1.2 INCHES OF THAT IN 1 1/2 HOURS.
Jan 20, 1:40 PM CSTSNOW 2.5Elburn, ILSTORM TOTAL SO FAR. 1.5 INCHES BETWEEN 1200 PM AND 130 PM. HEAVY SNOW AND 1/4 MILE VISIBILITY AT TIME OF REPORT.
Jan 20, 1:50 PM CSTSNOW 3.5Forreston, ILSTORM TOTAL SO FAR. RELAYED BY WREX.
Jan 20, 1:55 PM CSTSNOW 1.9Batavia, ILSTORM TOTAL SO FAR.
Jan 20, 2:05 PM CSTSNOW 3Rockford, ILSTORM TOTAL SO FAR.
Jan 20, 2:13 PM CSTSNOW 2.54 Nw Rockford, IL
Jan 20, 2:30 PM CSTSNOW 2.43 Se Aurora, ILSNOW STARTED AT 1015 AM. PAST HOUR 1.1. SNOW FLAKES ARE GETTING BIGGER.
Jan 20, 2:30 PM CSTSNOW 4.5Dixon, ILIDOT ESTIMATED STORM TOTAL OF 4 TO 5 INCHES SO FAR.
Jan 20, 2:40 PM CSTSNOW 2.8Geneva, ILSTORM TOTAL SO FAR. HEAVY SNOW AT TIME OF REPORT...WITH 1/4 MILE VISIBILITY.
Jan 20, 2:45 PM CSTSNOW 1.92 Ne Cary, ILSTORM TOTAL SO FAR...WITH MODERATE SNOW AT TIME OF REPORT.
Jan 20, 2:45 PM CSTSNOW 22 Se Aurora, ILSTORM TOTAL SO FAR NEAR RUSH COPLEY MEDICAL CENTER.
Jan 20, 2:45 PM CSTSNOW 3.2Sandwich, ILSTORM TOTAL SO FAR...WITH HEAVY SNOW AT TIME OF REPORT.
Jan 20, 2:55 PM CSTSNOW 3Glen Ellyn, ILESTIMATED STORM TOTAL SO FAR. HEAVY SNOW AT TIME OF REPORT.
Jan 20, 2:55 PM CSTSNOW 3.5Byron, ILSTORM TOTAL SO FAR. RELAYED BY WREX.
Jan 20, 2:55 PM CSTSNOW 3.5Cherry Valley, ILSTORM TOTAL SO FAR. RELAYED BY WTVO.
Jan 20, 2:55 PM CSTSNOW 3.5De Kalb, ILSTORM TOTAL SO FAR ON NIU CAMPUS.
Jan 20, 3:00 PM CSTSNOW 2.6Batavia, ILSTORM TOTAL SO FAR.
Jan 20, 3:00 PM CSTSNOW 4.3Elburn, ILSTORM TOTAL SO FAR. HEAVY SNOW WITH 1/4 MILE VISIBILITY. 1.75 INCHES BETWEEN 130 PM AND 300 PM.
Jan 20, 3:30 PM CSTSNOW 34 W Huntley, ILSTORM TOTAL SO FAR. SNOWING SINCE 1030 AM.
Jan 20, 3:30 PM CSTSNOW 3Dupage Airport, ILSTORM TOTAL SO FAR.
Jan 20, 3:30 PM CSTSNOW 3Huntley, ILSTORM TOTAL SO FAR.
Jan 20, 3:30 PM CSTSNOW 3.12 Ssw Lisle, ILSTORM TOTAL SO FAR.
Jan 20, 3:30 PM CSTSNOW 3.4Sse Carol Stream, ILSTORM TOTAL SO FAR. HEAVY SNOW AT THIS TIME. ONE SPINOUT IN CAROL STREAM ON ST. CHARLES ROAD E. OF GARY AVENUE.
Jan 20, 3:30 PM CSTSNOW 3.53 Se Aurora, ILSTORM TOTAL SO FAR. LAST HOUR 1.1 INCHES.
Jan 20, 3:35 PM CSTSNOW 2.3Fox Lake, ILSTORM TOTAL SO FAR.
Jan 20, 3:35 PM CSTSNOW 3.8Capron, ILSTORM TOTAL SO FAR. RELAYED BY WTVO.
Jan 20, 3:44 PM CSTSNOW 4Loves Park, ILSTORM TOTAL SO FAR. RELAYED BY WREX.
Jan 20, 3:45 PM CSTSNOW 2.41 W Beach Park, ILSTORM TOTAL SO FAR. ALL ROADS SNOW PACKED AND VERY SLIPPERY.
Jan 20, 3:45 PM CSTSNOW 3Rochelle, ILSTORM TOTAL SO FAR. MODERATE SNOWFALL RATE.
Jan 20, 3:58 PM CSTSNOW 3.8Belvidere, ILSTORM TOTAL SO FAR. RELAYED BY WREX.
Jan 20, 4:00 PM CSTSNOW 3.5Dupage Airport, ILSTORM TOTAL SO FAR.
Jan 20, 4:00 PM CSTSNOW 4Batavia, ILSTORM TOTAL SO FAR. 1.4 INCHES IN THE LAST HOUR.
Jan 20, 4:00 PM CSTSNOW 4Rockford Airport, ILSTORM TOTAL SO FAR. 3.6 INCHES SINCE 1200 PM.
Jan 20, 4:05 PM CSTSNOW 3.5Dupage Airport, ILSTORM TOTAL SO FAR.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Davenport, (KDVN), launched 00:00Z, 3.4 hours before the alert went out and 159 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Davenport, at 00:00Z on 2012-01-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Davenport, at 00:00Z on 2012-01-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -26 square meters per square second.1939587897117136156175Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1787 m above ground
0-6 km bulk shear
86 kt
0-1 km storm-relative helicity
-26 m²/s²
0-3 km storm-relative helicity
239 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

369 
WWUS43 KLOT 200326
WSWLOT

URGENT - WINTER WEATHER MESSAGE
NATIONAL WEATHER SERVICE CHICAGO IL
926 PM CST THU JAN 19 2012

ILZ003-004-008-011-201130-
/O.UPG.KLOT.WW.Y.0003.120120T1200Z-120121T0300Z/
/O.NEW.KLOT.WS.W.0002.120120T1200Z-120121T0300Z/
WINNEBAGO-BOONE-OGLE-DE KALB-
INCLUDING THE CITIES OF...ROCKFORD...BELVIDERE...OREGON...DEKALB
926 PM CST THU JAN 19 2012

...WINTER STORM WARNING IN EFFECT FROM 6 AM TO 9 PM CST FRIDAY...

THE NATIONAL WEATHER SERVICE IN CHICAGO HAS ISSUED A WINTER STORM
WARNING FOR HEAVY SNOW...WHICH IS IN EFFECT FROM 6 AM TO 9 PM CST
FRIDAY. THE WINTER WEATHER ADVISORY IS NO LONGER IN EFFECT.

* TIMING...SNOW WILL DEVELOP DURING THE EARLY TO MID MORNING 
  HOURS FRIDAY AND CONTINUE THROUGH THE DAY ENDING DURING THE 
  EVENING. THE HEAVIEST SNOWFALL WILL OCCUR DURING THE LATE 
  MORNING INTO THE MID AFTERNOON HOURS. 

* ACCUMULATIONS...SNOWFALL TOTALS OF 5 TO 8 INCHES CAN BE EXPECTED. 

* HAZARDS...SNOW COULD FALL RATHER HEAVILY AT TIMES RESULTING IN
  REDUCED VISIBILITIES AND SNOWFALL RATES OF AROUND ONE INCH PER
  HOUR AT TIMES.

* IMPACTS...ACCUMULATING SNOW WILL CAUSE SIGNIFICANTLY INCREASED
  TRAVEL TIMES...RESULTING IN A PARTICULARLY TREACHEROUS AFTERNOON
  COMMUTE FRIDAY. IN ADDITION...VERY COLD TEMPERATURES IN THE
  TEENS WILL MAKE SALT LESS EFFECTIVE AND COMBINE WITH HEAVY
  SNOWFALL RATES TO MAKE IT HARDER FOR ROAD CREWS TO KEEP ROADS
  CLEAR OF SNOW AND ICE. THE SNOW WILL ALSO RESULT IN SIGNIFICANT
  DISRUPTIONS TO AIR TRAVEL AS WELL.


PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER STORM WARNING FOR HEAVY SNOW MEANS SEVERE WINTER WEATHER
CONDITIONS ARE EXPECTED OR OCCURRING. SIGNIFICANT AMOUNTS OF SNOW
ARE FORECAST THAT WILL MAKE TRAVEL DANGEROUS. ONLY TRAVEL IN AN
EMERGENCY. IF YOU MUST TRAVEL...KEEP AN EXTRA FLASHLIGHT...
FOOD...AND WATER IN YOUR VEHICLE IN CASE OF AN EMERGENCY.

&&

$$

ILZ005-006-012>014-201130-
/O.UPG.KLOT.WW.Y.0003.120120T1500Z-120121T0600Z/
/O.NEW.KLOT.WS.W.0002.120120T1500Z-120121T0600Z/
MCHENRY-LAKE IL-KANE-DUPAGE-COOK-
INCLUDING THE CITIES OF...WOODSTOCK...WAUKEGAN...AURORA...
WHEATON...CHICAGO
926 PM CST THU JAN 19 2012

...WINTER STORM WARNING IN EFFECT FROM 9 AM FRIDAY TO MIDNIGHT
CST FRIDAY NIGHT...

THE NATIONAL WEATHER SERVICE IN CHICAGO HAS ISSUED A WINTER STORM
WARNING FOR HEAVY SNOW...WHICH IS IN EFFECT FROM 9 AM FRIDAY TO
MIDNIGHT CST FRIDAY NIGHT. THE WINTER WEATHER ADVISORY IS NO
LONGER IN EFFECT.

* TIMING...SNOW WILL DEVELOP DURING THE MID TO LATE MORNING 
  HOURS FRIDAY AND CONTINUE THROUGH THE DAY ENDING FRIDAY NIGHT. 
  THE HEAVIEST SNOWFALL WILL OCCUR DURING THE AFTERNOON FRIDAY. 

* ACCUMULATIONS...SNOWFALL TOTALS OF 5 TO 8 INCHES CAN BE EXPECTED.

* HAZARDS...SNOW COULD FALL RATHER HEAVILY AT TIMES RESULTING IN
  REDUCED VISIBILITIES AND SNOWFALL RATES OF AROUND ONE INCH PER
  HOUR AT TIMES.

* IMPACTS...ACCUMULATING SNOW WILL CAUSE SIGNIFICANTLY INCREASED
  TRAVEL TIMES...RESULTING IN A PARTICULARLY TREACHEROUS AFTERNOON
  COMMUTE FRIDAY. IN ADDITION...VERY COLD TEMPERATURES IN THE
  TEENS WILL MAKE SALT LESS EFFECTIVE AND COMBINE WITH HEAVY
  SNOWFALL RATES TO MAKE IT HARDER FOR ROAD CREWS TO KEEP ROADS
  CLEAR OF SNOW AND ICE. THE SNOW WILL ALSO RESULT IN SIGNIFICANT
  DISRUPTIONS TO AIR TRAVEL AS WELL.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER STORM WARNING FOR HEAVY SNOW MEANS SEVERE WINTER WEATHER
CONDITIONS ARE EXPECTED OR OCCURRING. SIGNIFICANT AMOUNTS OF SNOW
ARE FORECAST THAT WILL MAKE TRAVEL DANGEROUS. ONLY TRAVEL IN AN
EMERGENCY. IF YOU MUST TRAVEL...KEEP AN EXTRA FLASHLIGHT...
FOOD...AND WATER IN YOUR VEHICLE IN CASE OF AN EMERGENCY.

&&

$$

ILZ010-201130-
/O.CON.KLOT.WW.Y.0003.120120T1200Z-120121T0300Z/
LEE-
INCLUDING THE CITY OF...DIXON
926 PM CST THU JAN 19 2012

...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 6 AM TO 9 PM
CST FRIDAY...

A WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 6 AM TO 9 PM CST
FRIDAY. 

* TIMING...SNOW WILL DEVELOP DURING THE EARLY TO MID MORNING 
  HOURS FRIDAY AND CONTINUE THROUGH THE DAY ENDING DURING THE 
  EVENING. THE HEAVIEST SNOWFALL WILL OCCUR DURING THE LATE 
  MORNING INTO THE MID AFTERNOON HOURS. 

* ACCUMULATIONS...SNOWFALL TOTALS OF 3 TO 6 INCHES CAN BE 
  EXPECTED WITH LOCALLY HEAVIER TOTALS POSSIBLE. 

* HAZARDS...SNOW COULD FALL RATHER HEAVILY AT TIMES RESULTING IN 
  REDUCED VISIBILITIES AND SNOWFALL RATES OF A HALF INCH TO INCH 
  PER HOUR AT TIMES. 

* IMPACTS...ACCUMULATING SNOW WILL CAUSE SIGNIFICANTLY INCREASED 
  TRAVEL TIMES...RESULTING IN A PARTICULARLY TREACHEROUS 
  AFTERNOON COMMUTE FRIDAY. IN ADDITION...VERY COLD TEMPERATURES 
  IN THE TEENS WILL MAKE SALT LESS EFFECTIVE MAKING IT HARDER 
  FOR ROAD CREWS TO KEEP ROADS CLEAR OF SNOW AND ICE. THE SNOW 
  WILL ALSO RESULT IN SIGNIFICANT DISRUPTIONS TO AIR TRAVEL AS 
  WELL. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY FOR SNOW MEANS THAT PERIODS OF SNOW
WILL CAUSE PRIMARILY TRAVEL DIFFICULTIES. BE PREPARED FOR SNOW
COVERED ROADS AND LIMITED VISIBILITIES...AND USE CAUTION WHILE
DRIVING.

&&

$$

ILZ020-022-INZ001-002-201130-
/O.CON.KLOT.WW.Y.0003.120120T1500Z-120121T0600Z/
KENDALL-WILL-LAKE IN-PORTER-
INCLUDING THE CITIES OF...OSWEGO...JOLIET...GARY...VALPARAISO
926 PM CST THU JAN 19 2012

...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 9 AM FRIDAY TO
MIDNIGHT CST FRIDAY NIGHT...

A WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 9 AM FRIDAY TO
MIDNIGHT CST FRIDAY NIGHT. 

* TIMING...SNOW WILL DEVELOP DURING THE MID TO LATE MORNING 
  HOURS FRIDAY AND CONTINUE THROUGH THE DAY ENDING FRIDAY NIGHT. 
  THE HEAVIEST SNOWFALL WILL OCCUR DURING THE AFTERNOON FRIDAY. 

* ACCUMULATIONS...SNOWFALL TOTALS OF 3 TO 6 INCHES CAN BE 
  EXPECTED WITH LOCALLY HEAVIER TOTALS POSSIBLE. 

* HAZARDS...SNOW COULD FALL RATHER HEAVILY AT TIMES RESULTING IN 
  REDUCED VISIBILITIES AND SNOWFALL RATES OF A HALF INCH TO INCH 
  PER HOUR AT TIMES. 

* IMPACTS...ACCUMULATING SNOW WILL CAUSE SIGNIFICANTLY INCREASED 
  TRAVEL TIMES...RESULTING IN A PARTICULARLY TREACHEROUS 
  AFTERNOON COMMUTE FRIDAY. IN ADDITION...VERY COLD TEMPERATURES 
  IN THE TEENS WILL MAKE SALT LESS EFFECTIVE MAKING IT HARDER 
  FOR ROAD CREWS TO KEEP ROADS CLEAR OF SNOW AND ICE. THE SNOW 
  WILL ALSO RESULT IN SIGNIFICANT DISRUPTIONS TO AIR TRAVEL AS 
  WELL. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY FOR SNOW MEANS THAT PERIODS OF SNOW
WILL CAUSE PRIMARILY TRAVEL DIFFICULTIES. BE PREPARED FOR SNOW
COVERED ROADS AND LIMITED VISIBILITIES...AND USE CAUTION WHILE
DRIVING.

&&

$$

MDB/RATZER
5 follow-up statements
555 
WWUS43 KLOT 200952
WSWLOT

URGENT - WINTER WEATHER MESSAGE
NATIONAL WEATHER SERVICE CHICAGO IL
352 AM CST FRI JAN 20 2012

ILZ003-004-008-011-201800-
/O.CON.KLOT.WS.W.0002.120120T1200Z-120121T0300Z/
WINNEBAGO-BOONE-OGLE-DE KALB-
INCLUDING THE CITIES OF...ROCKFORD...BELVIDERE...OREGON...DEKALB
352 AM CST FRI JAN 20 2012

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 9 PM CST THIS
EVENING...

A WINTER STORM WARNING REMAINS IN EFFECT UNTIL 9 PM CST THIS
EVENING. 

* TIMING...SNOW WILL DEVELOP DURING THE EARLY TO MID MORNING HOURS
  AND CONTINUE THROUGH THIS AFTERNOON...ENDING THIS EVENING. THE
  HEAVIEST SNOWFALL WILL OCCUR DURING THE LATE MORNING INTO THE
  MID AFTERNOON.

* ACCUMULATIONS...SNOWFALL TOTALS OF 5 TO 8 INCHES CAN BE 
  EXPECTED.

* HAZARDS...SNOW WILL FALL HEAVILY AT TIMES RESULTING IN REDUCED
  VISIBILITIES AND SNOWFALL RATES OF AROUND ONE INCH PER HOUR AT
  TIMES.

* IMPACTS...ACCUMULATING SNOW WILL CAUSE SIGNIFICANTLY INCREASED
  TRAVEL TIMES...RESULTING IN A PARTICULARLY TREACHEROUS AFTERNOON
  COMMUTE. IN ADDITION...VERY COLD TEMPERATURES IN THE TEENS WILL
  MAKE SALT LESS EFFECTIVE AND COMBINE WITH HEAVY SNOWFALL RATES
  TO MAKE IT HARDER FOR ROAD CREWS TO KEEP ROADS CLEAR OF SNOW AND
  ICE. THE SNOW WILL ALSO RESULT IN SIGNIFICANT DISRUPTIONS TO AIR
  TRAVEL AS WELL.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER STORM WARNING FOR HEAVY SNOW MEANS SEVERE WINTER WEATHER
CONDITIONS ARE EXPECTED OR OCCURRING. SIGNIFICANT AMOUNTS OF SNOW
ARE FORECAST THAT WILL MAKE TRAVEL DANGEROUS. ONLY TRAVEL IN AN
EMERGENCY. IF YOU MUST TRAVEL...KEEP AN EXTRA FLASHLIGHT...
FOOD...AND WATER IN YOUR VEHICLE IN CASE OF AN EMERGENCY.

&&

$$

ILZ005-006-012>014-201800-
/O.CON.KLOT.WS.W.0002.120120T1500Z-120121T0600Z/
MCHENRY-LAKE IL-KANE-DUPAGE-COOK-
INCLUDING THE CITIES OF...WOODSTOCK...WAUKEGAN...AURORA...
WHEATON...CHICAGO
352 AM CST FRI JAN 20 2012

...WINTER STORM WARNING REMAINS IN EFFECT FROM 9 AM THIS MORNING
TO MIDNIGHT CST TONIGHT...

A WINTER STORM WARNING REMAINS IN EFFECT FROM 9 AM THIS MORNING
TO MIDNIGHT CST TONIGHT. 

* TIMING...SNOW WILL DEVELOP DURING THE MID TO LATE MORNING HOURS
  AND CONTINUE THROUGH THIS AFTERNOON...ENDING TONIGHT. THE
  HEAVIEST SNOWFALL WILL OCCUR THIS AFTERNOON.

* ACCUMULATIONS...SNOWFALL TOTALS OF 5 TO 8 INCHES CAN BE 
  EXPECTED.

* HAZARDS...SNOW WILL FALL HEAVILY AT TIMES RESULTING IN REDUCED
  VISIBILITIES AND SNOWFALL RATES OF AROUND ONE INCH PER HOUR AT
  TIMES.

* IMPACTS...ACCUMULATING SNOW WILL CAUSE SIGNIFICANTLY INCREASED
  TRAVEL TIMES...RESULTING IN A PARTICULARLY TREACHEROUS COMMUTE
  THIS AFTERNOON. IN ADDITION...VERY COLD TEMPERATURES IN THE
  TEENS WILL MAKE SALT LESS EFFECTIVE AND COMBINE WITH HEAVY
  SNOWFALL RATES TO MAKE IT HARDER FOR ROAD CREWS TO KEEP ROADS
  CLEAR OF SNOW AND ICE. THE SNOW WILL ALSO RESULT IN SIGNIFICANT
  DISRUPTIONS TO AIR TRAVEL AS WELL.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER STORM WARNING FOR HEAVY SNOW MEANS SEVERE WINTER WEATHER
CONDITIONS ARE EXPECTED OR OCCURRING. SIGNIFICANT AMOUNTS OF SNOW
ARE FORECAST THAT WILL MAKE TRAVEL DANGEROUS. ONLY TRAVEL IN AN
EMERGENCY. IF YOU MUST TRAVEL...KEEP AN EXTRA FLASHLIGHT...
FOOD...AND WATER IN YOUR VEHICLE IN CASE OF AN EMERGENCY.

&&

$$

ILZ019-021-023-INZ010-011-019-201800-
/O.EXA.KLOT.WW.Y.0003.120120T1500Z-120121T0600Z/
LA SALLE-GRUNDY-KANKAKEE-NEWTON-JASPER-BENTON-
INCLUDING THE CITIES OF...OTTAWA...MORRIS...KANKAKEE...MOROCCO...
RENSSELAER...FOWLER
352 AM CST FRI JAN 20 2012 /452 AM EST FRI JAN 20 2012/

...WINTER WEATHER ADVISORY IN EFFECT FROM 9 AM CST /10 AM EST/
THIS MORNING TO MIDNIGHT CST /1 AM EST/ TONIGHT...

THE NATIONAL WEATHER SERVICE IN CHICAGO HAS ISSUED A WINTER
WEATHER ADVISORY FOR SNOW...WHICH IS IN EFFECT FROM 9 AM CST /10
AM EST/ THIS MORNING TO MIDNIGHT CST /1 AM EST/ TONIGHT.

* TIMING...SNOW WILL DEVELOP DURING THE MID TO LATE MORNING HOURS
  AND CONTINUE THROUGH THIS AFTERNOON...THEN ENDING TONIGHT. THE
  HEAVIEST SNOWFALL WILL OCCUR THIS AFTERNOON.

* ACCUMULATIONS...SNOWFALL TOTALS OF 3 TO 6 INCHES CAN BE 
  EXPECTED WITH LOCALLY HEAVIER TOTALS POSSIBLE. 

* HAZARDS...SNOW COULD FALL RATHER HEAVILY AT TIMES RESULTING IN 
  REDUCED VISIBILITIES AND SNOWFALL RATES OF A HALF INCH TO INCH 
  PER HOUR AT TIMES. 

* IMPACTS...ACCUMULATING SNOW WILL CAUSE SIGNIFICANTLY INCREASED
  TRAVEL TIMES...RESULTING IN A PARTICULARLY TREACHEROUS COMMUTE
  THIS AFTERNOON. IN ADDITION...VERY COLD TEMPERATURES IN THE
  TEENS WILL MAKE SALT LESS EFFECTIVE MAKING IT HARDER FOR ROAD
  CREWS TO KEEP ROADS CLEAR OF SNOW AND ICE. THE SNOW WILL ALSO
  RESULT IN SIGNIFICANT DISRUPTIONS TO AIR TRAVEL AS WELL.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY FOR SNOW MEANS THAT PERIODS OF SNOW
WILL CAUSE PRIMARILY TRAVEL DIFFICULTIES. BE PREPARED FOR SNOW
COVERED ROADS AND LIMITED VISIBILITIES...AND USE CAUTION WHILE
DRIVING.

&&

$$

ILZ010-201800-
/O.CON.KLOT.WW.Y.0003.120120T1200Z-120121T0300Z/
LEE-
INCLUDING THE CITY OF...DIXON
352 AM CST FRI JAN 20 2012

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 9 PM CST THIS
EVENING...

A WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 9 PM CST THIS
EVENING. 

* TIMING...SNOW WILL DEVELOP DURING THE EARLY TO MID MORNING HOURS
  AND CONTINUE THROUGH THIS AFTERNOON BEFORE ENDING THIS EVENING.
  THE HEAVIEST SNOWFALL WILL OCCUR DURING THE LATE MORNING INTO
  THE MID AFTERNOON.

* ACCUMULATIONS...SNOWFALL TOTALS OF 3 TO 6 INCHES CAN BE 
  EXPECTED WITH LOCALLY HEAVIER TOTALS POSSIBLE. 

* HAZARDS...SNOW COULD FALL RATHER HEAVILY AT TIMES RESULTING IN 
  REDUCED VISIBILITIES AND SNOWFALL RATES OF A HALF INCH TO INCH 
  PER HOUR AT TIMES. 

* IMPACTS...ACCUMULATING SNOW WILL CAUSE SIGNIFICANTLY INCREASED
  TRAVEL TIMES...RESULTING IN A PARTICULARLY TREACHEROUS COMMUTE
  THIS AFTERNOON. IN ADDITION...VERY COLD TEMPERATURES IN THE
  TEENS WILL MAKE SALT LESS EFFECTIVE MAKING IT HARDER FOR ROAD
  CREWS TO KEEP ROADS CLEAR OF SNOW AND ICE. THE SNOW WILL ALSO
  RESULT IN SIGNIFICANT DISRUPTIONS TO AIR TRAVEL AS WELL.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY FOR SNOW MEANS THAT PERIODS OF SNOW
WILL CAUSE PRIMARILY TRAVEL DIFFICULTIES. BE PREPARED FOR SNOW
COVERED ROADS AND LIMITED VISIBILITIES...AND USE CAUTION WHILE
DRIVING.

&&

$$

ILZ020-022-INZ001-002-201800-
/O.CON.KLOT.WW.Y.0003.120120T1500Z-120121T0600Z/
KENDALL-WILL-LAKE IN-PORTER-
INCLUDING THE CITIES OF...OSWEGO...JOLIET...GARY...VALPARAISO
352 AM CST FRI JAN 20 2012

...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 9 AM THIS
MORNING TO MIDNIGHT CST TONIGHT...

A WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 9 AM THIS
MORNING TO MIDNIGHT CST TONIGHT. 

* TIMING...SNOW WILL DEVELOP DURING THE MID TO LATE MORNING HOURS
  TODAY AND CONTINUE THROUGH THE AFTERNOON ENDING TONIGHT. THE
  HEAVIEST SNOWFALL WILL OCCUR THIS AFTERNOON.

* ACCUMULATIONS...SNOWFALL TOTALS OF 4 TO 6 INCHES CAN BE 
  EXPECTED WITH LOCALLY HEAVIER TOTALS POSSIBLE. 

* HAZARDS...SNOW COULD FALL RATHER HEAVILY AT TIMES RESULTING IN 
  REDUCED VISIBILITIES AND SNOWFALL RATES OF A HALF INCH TO INCH 
  PER HOUR AT TIMES. 

* IMPACTS...ACCUMULATING SNOW WILL CAUSE SIGNIFICANTLY INCREASED
  TRAVEL TIMES...RESULTING IN A PARTICULARLY TREACHEROUS COMMUTE
  THIS AFTERNOON. IN ADDITION...VERY COLD TEMPERATURES IN THE
  TEENS WILL MAKE SALT LESS EFFECTIVE MAKING IT HARDER FOR ROAD
  CREWS TO KEEP ROADS CLEAR OF SNOW AND ICE. THE SNOW WILL ALSO
  RESULT IN SIGNIFICANT DISRUPTIONS TO AIR TRAVEL AS WELL.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY FOR SNOW MEANS THAT PERIODS OF SNOW
WILL CAUSE PRIMARILY TRAVEL DIFFICULTIES. BE PREPARED FOR SNOW
COVERED ROADS AND LIMITED VISIBILITIES...AND USE CAUTION WHILE
DRIVING.

&&

$$

IZZI
530 
WWUS43 KLOT 201618
WSWLOT

URGENT - WINTER WEATHER MESSAGE
NATIONAL WEATHER SERVICE CHICAGO IL
1018 AM CST FRI JAN 20 2012

ILZ003-004-008-011-210030-
/O.CON.KLOT.WS.W.0002.000000T0000Z-120121T0300Z/
WINNEBAGO-BOONE-OGLE-DE KALB-
INCLUDING THE CITIES OF...ROCKFORD...BELVIDERE...OREGON...DEKALB
1018 AM CST FRI JAN 20 2012

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 9 PM CST THIS
EVENING...

A WINTER STORM WARNING REMAINS IN EFFECT UNTIL 9 PM CST THIS
EVENING. 

* TIMING...SNOW WILL CONTINUE THROUGH THIS AFTERNOON...ENDING THIS
  EVENING. THE HEAVIEST SNOWFALL WILL OCCUR DURING THE EARLY
  AFTERNOON HOURS.

* ACCUMULATIONS...SNOWFALL TOTALS OF 4 TO 7 INCHES CAN BE
  EXPECTED WITH LOCALLY HIGHER AMOUNTS POSSIBLE.

* HAZARDS...SNOW WILL FALL HEAVILY AT TIMES RESULTING IN REDUCED 
  VISIBILITIES AND SNOWFALL RATES OF AROUND ONE INCH PER HOUR AT 
  TIMES. 

* IMPACTS...ACCUMULATING SNOW WILL CAUSE SIGNIFICANTLY INCREASED 
  TRAVEL TIMES...RESULTING IN A PARTICULARLY TREACHEROUS 
  AFTERNOON COMMUTE. IN ADDITION...VERY COLD TEMPERATURES IN THE 
  TEENS WILL MAKE SALT LESS EFFECTIVE AND COMBINE WITH HEAVY 
  SNOWFALL RATES TO MAKE IT HARDER FOR ROAD CREWS TO KEEP ROADS 
  CLEAR OF SNOW AND ICE. THE SNOW WILL ALSO RESULT IN 
  SIGNIFICANT DISRUPTIONS TO AIR TRAVEL AS WELL. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER STORM WARNING FOR HEAVY SNOW MEANS SEVERE WINTER WEATHER
CONDITIONS ARE EXPECTED OR OCCURRING. SIGNIFICANT AMOUNTS OF SNOW
ARE FORECAST THAT WILL MAKE TRAVEL DANGEROUS. ONLY TRAVEL IN AN
EMERGENCY. IF YOU MUST TRAVEL...KEEP AN EXTRA FLASHLIGHT...
FOOD...AND WATER IN YOUR VEHICLE IN CASE OF AN EMERGENCY.

&&

$$

ILZ005-006-012>014-210030-
/O.CON.KLOT.WS.W.0002.000000T0000Z-120121T0600Z/
MCHENRY-LAKE IL-KANE-DUPAGE-COOK-
INCLUDING THE CITIES OF...WOODSTOCK...WAUKEGAN...AURORA...
WHEATON...CHICAGO
1018 AM CST FRI JAN 20 2012

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL MIDNIGHT CST
TONIGHT...

A WINTER STORM WARNING REMAINS IN EFFECT UNTIL MIDNIGHT CST
TONIGHT. 

* TIMING...SNOW WILL BEGIN TO FALL WITHIN THE NEXT HOUR OR TWO AND
  CONTINUE THROUGH THIS AFTERNOON...ENDING TONIGHT. THE HEAVIEST
  SNOWFALL WILL OCCUR DURING THE EARLY TO MID AFTERNOON HOURS.

* ACCUMULATIONS...SNOWFALL TOTALS OF 4 TO 7 INCHES CAN BE EXPECTED
  WITH LOCALLY HIGHER AMOUNTS POSSIBLE.

* HAZARDS...SNOW WILL FALL HEAVILY AT TIMES RESULTING IN REDUCED 
  VISIBILITIES AND SNOWFALL RATES OF AROUND ONE INCH PER HOUR AT 
  TIMES. 

* IMPACTS...ACCUMULATING SNOW WILL CAUSE SIGNIFICANTLY INCREASED 
  TRAVEL TIMES...RESULTING IN A PARTICULARLY TREACHEROUS COMMUTE 
  THIS AFTERNOON. IN ADDITION...VERY COLD TEMPERATURES IN THE 
  TEENS WILL MAKE SALT LESS EFFECTIVE AND COMBINE WITH HEAVY 
  SNOWFALL RATES TO MAKE IT HARDER FOR ROAD CREWS TO KEEP ROADS 
  CLEAR OF SNOW AND ICE. THE SNOW WILL ALSO RESULT IN 
  SIGNIFICANT DISRUPTIONS TO AIR TRAVEL AS WELL. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER STORM WARNING FOR HEAVY SNOW MEANS SEVERE WINTER WEATHER
CONDITIONS ARE EXPECTED OR OCCURRING. SIGNIFICANT AMOUNTS OF SNOW
ARE FORECAST THAT WILL MAKE TRAVEL DANGEROUS. ONLY TRAVEL IN AN
EMERGENCY. IF YOU MUST TRAVEL...KEEP AN EXTRA FLASHLIGHT...
FOOD...AND WATER IN YOUR VEHICLE IN CASE OF AN EMERGENCY.

&&

$$

ILZ010-210030-
/O.CON.KLOT.WW.Y.0003.000000T0000Z-120121T0300Z/
LEE-
INCLUDING THE CITY OF...DIXON
1018 AM CST FRI JAN 20 2012

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 9 PM CST THIS
EVENING...

A WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 9 PM CST THIS
EVENING. 

* TIMING...SNOW WILL CONTINUE THROUGH THE AFTERNOON BEFORE ENDING
  THIS EVENING. THE HEAVIEST SNOWFALL WILL OCCUR DURING THE EARLY
  AFTERNOON HOURS.

* ACCUMULATIONS...SNOWFALL TOTALS OF 3 TO 6 INCHES CAN BE
  EXPECTED WITH LOCALLY HEAVIER TOTALS POSSIBLE.

* HAZARDS...SNOW COULD FALL RATHER HEAVILY AT TIMES RESULTING IN
  REDUCED VISIBILITIES AND SNOWFALL RATES OF A HALF INCH TO ONE
  INCH PER HOUR AT TIMES.

* IMPACTS...ACCUMULATING SNOW WILL CAUSE SIGNIFICANTLY INCREASED 
  TRAVEL TIMES...RESULTING IN A PARTICULARLY TREACHEROUS COMMUTE 
  THIS AFTERNOON. IN ADDITION...VERY COLD TEMPERATURES IN THE 
  TEENS WILL MAKE SALT LESS EFFECTIVE MAKING IT HARDER FOR ROAD 
  CREWS TO KEEP ROADS CLEAR OF SNOW AND ICE. THE SNOW WILL ALSO 
  RESULT IN SIGNIFICANT DISRUPTIONS TO AIR TRAVEL AS WELL. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY FOR SNOW MEANS THAT PERIODS OF SNOW
WILL CAUSE PRIMARILY TRAVEL DIFFICULTIES. BE PREPARED FOR SNOW
COVERED ROADS AND LIMITED VISIBILITIES...AND USE CAUTION WHILE
DRIVING.

&&

$$

ILZ019>023-INZ001-002-010-011-019-210030-
/O.CON.KLOT.WW.Y.0003.000000T0000Z-120121T0600Z/
LA SALLE-KENDALL-GRUNDY-WILL-KANKAKEE-LAKE IN-PORTER-NEWTON-
JASPER-BENTON-
INCLUDING THE CITIES OF...OTTAWA...OSWEGO...MORRIS...JOLIET...
KANKAKEE...GARY...VALPARAISO...MOROCCO...RENSSELAER...FOWLER
1018 AM CST FRI JAN 20 2012 /1118 AM EST FRI JAN 20 2012/

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL MIDNIGHT CST
/1 AM EST/ TONIGHT...

A WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL MIDNIGHT CST
/1 AM EST/ TONIGHT. 

* TIMING...SNOW WILL CONTINUE TO MOVE EASTWARD THROUGH THE AREA AND
  PERSIST THROUGH THE AFTERNOON ENDING TONIGHT. THE HEAVIEST
  SNOWFALL WILL OCCUR THIS AFTERNOON.

* ACCUMULATIONS...SNOWFALL TOTALS OF 4 TO 6 INCHES CAN BE 
  EXPECTED WITH LOCALLY HEAVIER TOTALS POSSIBLE. 

* HAZARDS...SNOW COULD FALL RATHER HEAVILY AT TIMES RESULTING IN 
  REDUCED VISIBILITIES AND SNOWFALL RATES OF A HALF INCH TO INCH 
  PER HOUR AT TIMES. 

* IMPACTS...ACCUMULATING SNOW WILL CAUSE SIGNIFICANTLY INCREASED 
  TRAVEL TIMES...RESULTING IN A PARTICULARLY TREACHEROUS COMMUTE 
  THIS AFTERNOON. IN ADDITION...VERY COLD TEMPERATURES IN THE 
  TEENS WILL MAKE SALT LESS EFFECTIVE MAKING IT HARDER FOR ROAD 
  CREWS TO KEEP ROADS CLEAR OF SNOW AND ICE. THE SNOW WILL ALSO 
  RESULT IN SIGNIFICANT DISRUPTIONS TO AIR TRAVEL AS WELL. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY FOR SNOW MEANS THAT PERIODS OF SNOW
WILL CAUSE PRIMARILY TRAVEL DIFFICULTIES. BE PREPARED FOR SNOW
COVERED ROADS AND LIMITED VISIBILITIES...AND USE CAUTION WHILE
DRIVING.

&&

$$

JEE
887 
WWUS43 KLOT 202059
WSWLOT

URGENT - WINTER WEATHER MESSAGE
NATIONAL WEATHER SERVICE CHICAGO IL
259 PM CST FRI JAN 20 2012

ILZ010-210300-
/O.UPG.KLOT.WW.Y.0003.000000T0000Z-120121T0300Z/
/O.EXA.KLOT.WS.W.0002.000000T0000Z-120121T0300Z/
LEE-
INCLUDING THE CITY OF...DIXON
259 PM CST FRI JAN 20 2012

...WINTER STORM WARNING IN EFFECT UNTIL 9 PM CST THIS EVENING...

THE NATIONAL WEATHER SERVICE IN CHICAGO HAS ISSUED A WINTER STORM
WARNING FOR SNOW...WHICH IS IN EFFECT UNTIL 9 PM CST THIS EVENING.
THE WINTER WEATHER ADVISORY IS NO LONGER IN EFFECT.

* TIMING...SNOW WILL CONTINUE THROUGH LATE THIS EVENING. THE
  HEAVIEST SNOWFALL WILL CONTINUE THROUGH THE EARLY EVENING
  HOURS.

* ACCUMULATIONS...SNOWFALL TOTALS OF 4 TO 7 INCHES CAN BE 
  EXPECTED WITH LOCALLY HIGHER AMOUNTS POSSIBLE. 

* HAZARDS...SNOW WILL FALL HEAVILY AT TIMES RESULTING IN REDUCED 
  VISIBILITIES AND SNOWFALL RATES OF AROUND ONE INCH PER HOUR AT 
  TIMES. 

* IMPACTS...ACCUMULATING SNOW WILL CAUSE SIGNIFICANTLY INCREASED
  TRAVEL TIMES...RESULTING IN A PARTICULARLY TREACHEROUS AFTERNOON
  COMMUTE. IN ADDITION...VERY COLD TEMPERATURES IN THE TEENS WILL
  MAKE SALT LESS EFFECTIVE AND COMBINE WITH HEAVY SNOWFALL RATES
  TO MAKE IT HARDER FOR ROAD CREWS TO KEEP ROADS CLEAR OF SNOW AND
  ICE. THE SNOW WILL ALSO RESULT IN SIGNIFICANT DISRUPTIONS TO AIR
  TRAVEL AS WELL.


PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER STORM WARNING FOR HEAVY SNOW MEANS SEVERE WINTER WEATHER
CONDITIONS ARE EXPECTED OR OCCURRING. SIGNIFICANT AMOUNTS OF SNOW
ARE FORECAST THAT WILL MAKE TRAVEL DANGEROUS. ONLY TRAVEL IN AN
EMERGENCY. IF YOU MUST TRAVEL...KEEP AN EXTRA FLASHLIGHT...
FOOD...AND WATER IN YOUR VEHICLE IN CASE OF AN EMERGENCY.

&&

$$

ILZ003-004-008-011-210300-
/O.CON.KLOT.WS.W.0002.000000T0000Z-120121T0300Z/
WINNEBAGO-BOONE-OGLE-DE KALB-
INCLUDING THE CITIES OF...ROCKFORD...BELVIDERE...OREGON...DEKALB
259 PM CST FRI JAN 20 2012

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 9 PM CST THIS
EVENING...

A WINTER STORM WARNING REMAINS IN EFFECT UNTIL 9 PM CST THIS
EVENING. 

* TIMING...SNOW WILL CONTINUE THROUGH LATE THIS EVENING. THE
  HEAVIEST SNOWFALL WILL OCCUR THROUGH THE EARLY EVENING HOURS.

* ACCUMULATIONS...SNOWFALL TOTALS OF 4 TO 7 INCHES CAN BE 
  EXPECTED WITH LOCALLY HIGHER AMOUNTS POSSIBLE. 

* HAZARDS...SNOW WILL FALL HEAVILY AT TIMES RESULTING IN REDUCED 
  VISIBILITIES AND SNOWFALL RATES OF AROUND ONE INCH PER HOUR AT 
  TIMES. 

* IMPACTS...ACCUMULATING SNOW WILL CAUSE SIGNIFICANTLY INCREASED 
  TRAVEL TIMES...RESULTING IN A PARTICULARLY TREACHEROUS 
  AFTERNOON COMMUTE. IN ADDITION...VERY COLD TEMPERATURES IN THE 
  TEENS WILL MAKE SALT LESS EFFECTIVE AND COMBINE WITH HEAVY 
  SNOWFALL RATES TO MAKE IT HARDER FOR ROAD CREWS TO KEEP ROADS 
  CLEAR OF SNOW AND ICE. THE SNOW WILL ALSO RESULT IN 
  SIGNIFICANT DISRUPTIONS TO AIR TRAVEL AS WELL. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER STORM WARNING FOR HEAVY SNOW MEANS SEVERE WINTER WEATHER
CONDITIONS ARE EXPECTED OR OCCURRING. SIGNIFICANT AMOUNTS OF SNOW
ARE FORECAST THAT WILL MAKE TRAVEL DANGEROUS. ONLY TRAVEL IN AN
EMERGENCY. IF YOU MUST TRAVEL...KEEP AN EXTRA FLASHLIGHT...
FOOD...AND WATER IN YOUR VEHICLE IN CASE OF AN EMERGENCY.

&&

$$

ILZ005-006-012>014-210500-
/O.CON.KLOT.WS.W.0002.000000T0000Z-120121T0600Z/
MCHENRY-LAKE IL-KANE-DUPAGE-COOK-
INCLUDING THE CITIES OF...WOODSTOCK...WAUKEGAN...AURORA...
WHEATON...CHICAGO
259 PM CST FRI JAN 20 2012

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL MIDNIGHT CST
TONIGHT...

A WINTER STORM WARNING REMAINS IN EFFECT UNTIL MIDNIGHT CST
TONIGHT. 

* TIMING...SNOW WILL CONTINUE THROUGH TONIGHT. THE HEAVIEST
  SNOWFALL WILL OCCUR THROUGH THE EARLY EVENING HOURS.

* ACCUMULATIONS...SNOWFALL TOTALS OF 4 TO 7 INCHES CAN BE 
  EXPECTED WITH LOCALLY HIGHER AMOUNTS POSSIBLE. 

* HAZARDS...SNOW WILL FALL HEAVILY AT TIMES RESULTING IN REDUCED 
  VISIBILITIES AND SNOWFALL RATES OF AROUND ONE INCH PER HOUR AT 
  TIMES. 

* IMPACTS...ACCUMULATING SNOW WILL CAUSE SIGNIFICANTLY INCREASED 
  TRAVEL TIMES...RESULTING IN A PARTICULARLY TREACHEROUS COMMUTE 
  THIS AFTERNOON. IN ADDITION...VERY COLD TEMPERATURES IN THE 
  TEENS WILL MAKE SALT LESS EFFECTIVE AND COMBINE WITH HEAVY 
  SNOWFALL RATES TO MAKE IT HARDER FOR ROAD CREWS TO KEEP ROADS 
  CLEAR OF SNOW AND ICE. THE SNOW WILL ALSO RESULT IN 
  SIGNIFICANT DISRUPTIONS TO AIR TRAVEL AS WELL. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER STORM WARNING FOR HEAVY SNOW MEANS SEVERE WINTER WEATHER
CONDITIONS ARE EXPECTED OR OCCURRING. SIGNIFICANT AMOUNTS OF SNOW
ARE FORECAST THAT WILL MAKE TRAVEL DANGEROUS. ONLY TRAVEL IN AN
EMERGENCY. IF YOU MUST TRAVEL...KEEP AN EXTRA FLASHLIGHT...
FOOD...AND WATER IN YOUR VEHICLE IN CASE OF AN EMERGENCY.

&&

$$

ILZ019>023-INZ001-002-010-011-019-210500-
/O.CON.KLOT.WW.Y.0003.000000T0000Z-120121T0600Z/
LA SALLE-KENDALL-GRUNDY-WILL-KANKAKEE-LAKE IN-PORTER-NEWTON-
JASPER-BENTON-
INCLUDING THE CITIES OF...OTTAWA...OSWEGO...MORRIS...JOLIET...
KANKAKEE...GARY...VALPARAISO...MOROCCO...RENSSELAER...FOWLER
259 PM CST FRI JAN 20 2012 /359 PM EST FRI JAN 20 2012/

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL MIDNIGHT CST
/1 AM EST/ TONIGHT...

A WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL MIDNIGHT CST
/1 AM EST/ TONIGHT. 

* TIMING...SNOW WILL CONTINUE THROUGH TONIGHT. THE HEAVIEST
  SNOWFALL WILL THROUGH EARLY THIS EVENING.

* ACCUMULATIONS...SNOWFALL TOTALS OF 4 TO 6 INCHES CAN BE 
  EXPECTED WITH LOCALLY HEAVIER TOTALS POSSIBLE. 

* HAZARDS...SNOW COULD FALL RATHER HEAVILY AT TIMES RESULTING IN 
  REDUCED VISIBILITIES AND SNOWFALL RATES OF A HALF INCH TO INCH 
  PER HOUR AT TIMES. 

* IMPACTS...ACCUMULATING SNOW WILL CAUSE SIGNIFICANTLY INCREASED 
  TRAVEL TIMES...RESULTING IN A PARTICULARLY TREACHEROUS COMMUTE 
  THIS AFTERNOON. IN ADDITION...VERY COLD TEMPERATURES IN THE 
  TEENS WILL MAKE SALT LESS EFFECTIVE MAKING IT HARDER FOR ROAD 
  CREWS TO KEEP ROADS CLEAR OF SNOW AND ICE. THE SNOW WILL ALSO 
  RESULT IN SIGNIFICANT DISRUPTIONS TO AIR TRAVEL AS WELL. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY FOR SNOW MEANS THAT PERIODS OF SNOW
WILL CAUSE PRIMARILY TRAVEL DIFFICULTIES. BE PREPARED FOR SNOW
COVERED ROADS AND LIMITED VISIBILITIES...AND USE CAUTION WHILE
DRIVING.

&&

$$

BMD
128 
WWUS43 KLOT 210214
WSWLOT

URGENT - WINTER WEATHER MESSAGE
NATIONAL WEATHER SERVICE CHICAGO IL
814 PM CST FRI JAN 20 2012

ILZ003-004-008-010-011-210315-
/O.CAN.KLOT.WS.W.0002.000000T0000Z-120121T0300Z/
WINNEBAGO-BOONE-OGLE-LEE-DE KALB-
INCLUDING THE CITIES OF...ROCKFORD...BELVIDERE...OREGON...DIXON...
DEKALB
814 PM CST FRI JAN 20 2012

...WINTER STORM WARNING IS CANCELLED...

THE NATIONAL WEATHER SERVICE IN CHICAGO HAS CANCELLED THE WINTER
STORM WARNING. 

HEAVY SNOWFALL HAS SHIFTED EAST. LIGHT SNOW SHOWERS TO FLURRIES
MAY PERSIST OVER THE NEXT HOUR...BUT LITTLE TO NO FURTHER
ACCUMULATION IS EXPECTED.

$$

ILZ019-210315-
/O.CAN.KLOT.WW.Y.0003.000000T0000Z-120121T0600Z/
LA SALLE-
INCLUDING THE CITY OF...OTTAWA
814 PM CST FRI JAN 20 2012

...WINTER WEATHER ADVISORY IS CANCELLED...

THE NATIONAL WEATHER SERVICE IN CHICAGO HAS CANCELLED THE WINTER
WEATHER ADVISORY. 

HEAVY SNOWFALL HAS SHIFTED EAST. LIGHT SNOW SHOWERS TO FLURRIES
MAY PERSIST OVER THE NEXT HOUR...BUT LITTLE TO NO FURTHER
ACCUMULATION IS EXPECTED.

$$

ILZ005-006-012>014-210600-
/O.CON.KLOT.WS.W.0002.000000T0000Z-120121T0600Z/
MCHENRY-LAKE IL-KANE-DUPAGE-COOK-
INCLUDING THE CITIES OF...WOODSTOCK...WAUKEGAN...AURORA...
WHEATON...CHICAGO
814 PM CST FRI JAN 20 2012

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL MIDNIGHT CST
TONIGHT...

A WINTER STORM WARNING REMAINS IN EFFECT UNTIL MIDNIGHT CST
TONIGHT. 

* TIMING...SNOW WILL CONTINUE INTO THE EARLY EVENING HOURS. 

* ACCUMULATIONS...STORM TOTAL SNOWFALL OF 4 TO 7 INCHES CAN BE
  EXPECTED.

* HAZARDS...SNOWFALL WILL CONTINUE TO TAPER OFF OVER THE NEXT FEW
  HOURS...BUT LIGHT WINDS MAY CAUSE SOME BLOWING AND DRIFTING OF
  THE FRESHLY FALLEN SNOW.

* IMPACTS...TRAVEL MAY REMAIN DIFFICULT UNTIL ROAD CREWS CAN CLEAR
  ALL ROADWAYS.  

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER STORM WARNING FOR HEAVY SNOW MEANS SEVERE WINTER WEATHER
CONDITIONS ARE EXPECTED OR OCCURRING. SIGNIFICANT AMOUNTS OF SNOW
ARE FORECAST THAT WILL MAKE TRAVEL DANGEROUS. ONLY TRAVEL IN AN
EMERGENCY. IF YOU MUST TRAVEL...KEEP AN EXTRA FLASHLIGHT...
FOOD...AND WATER IN YOUR VEHICLE IN CASE OF AN EMERGENCY.

&&

$$

ILZ020>023-INZ001-002-010-011-019-210600-
/O.CON.KLOT.WW.Y.0003.000000T0000Z-120121T0600Z/
KENDALL-GRUNDY-WILL-KANKAKEE-LAKE IN-PORTER-NEWTON-JASPER-BENTON-
INCLUDING THE CITIES OF...OSWEGO...MORRIS...JOLIET...KANKAKEE...
GARY...VALPARAISO...MOROCCO...RENSSELAER...FOWLER
814 PM CST FRI JAN 20 2012 /914 PM EST FRI JAN 20 2012/

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL MIDNIGHT CST
/1 AM EST/ TONIGHT...

A WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL MIDNIGHT CST
/1 AM EST/ TONIGHT. 

* TIMING...SNOW WILL CONTINUE INTO THE EARLY EVENING HOURS. 

* ACCUMULATIONS...STORM TOTAL SNOWFALL OF 4 TO 7 INCHES CAN BE
  EXPECTED.

* HAZARDS...SNOWFALL WILL CONTINUE TO TAPER OFF OVER THE NEXT FEW
  HOURS...BUT LIGHT WINDS MAY CAUSE SOME BLOWING AND DRIFTING OF
  THE FRESHLY FALLEN SNOW.

* IMPACTS...TRAVEL MAY REMAIN DIFFICULT UNTIL ROAD CREWS CAN CLEAR
  ALL ROADWAYS.  

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY FOR SNOW MEANS THAT PERIODS OF SNOW
WILL CAUSE PRIMARILY TRAVEL DIFFICULTIES. BE PREPARED FOR SNOW
COVERED ROADS AND LIMITED VISIBILITIES...AND USE CAUTION WHILE
DRIVING.

&&

$$

SHEA
068 
WWUS43 KLOT 210256
WSWLOT

URGENT - WINTER WEATHER MESSAGE
NATIONAL WEATHER SERVICE CHICAGO IL
856 PM CST FRI JAN 20 2012

ILZ005-006-012>014-210400-
/O.CAN.KLOT.WS.W.0002.000000T0000Z-120121T0600Z/
MCHENRY-LAKE IL-KANE-DUPAGE-COOK-
INCLUDING THE CITIES OF...WOODSTOCK...WAUKEGAN...AURORA...
WHEATON...CHICAGO
856 PM CST FRI JAN 20 2012

...WINTER STORM WARNING IS CANCELLED...

THE NATIONAL WEATHER SERVICE IN CHICAGO HAS CANCELLED THE WINTER
STORM WARNING. 

THE MAJORITY OF SNOWFALL HAS SHIFTED EAST. FLURRIES MAY PERSIST
OVER THE NEXT HOUR...BUT LITTLE TO NO FURTHER ACCUMULATION IS
EXPECTED.

$$

ILZ020>023-210400-
/O.CAN.KLOT.WW.Y.0003.000000T0000Z-120121T0600Z/
KENDALL-GRUNDY-WILL-KANKAKEE-
INCLUDING THE CITIES OF...OSWEGO...MORRIS...JOLIET...KANKAKEE
856 PM CST FRI JAN 20 2012

...WINTER WEATHER ADVISORY IS CANCELLED...

THE NATIONAL WEATHER SERVICE IN CHICAGO HAS CANCELLED THE WINTER
WEATHER ADVISORY. 

THE MAJORITY OF SNOWFALL HAS SHIFTED EAST. FLURRIES MAY PERSIST
OVER THE NEXT HOUR...BUT LITTLE TO NO FURTHER ACCUMULATION IS
EXPECTED.

$$

INZ001-002-010-011-019-210600-
/O.CON.KLOT.WW.Y.0003.000000T0000Z-120121T0600Z/
LAKE IN-PORTER-NEWTON-JASPER-BENTON-
INCLUDING THE CITIES OF...GARY...VALPARAISO...MOROCCO...
RENSSELAER...FOWLER
856 PM CST FRI JAN 20 2012 /956 PM EST FRI JAN 20 2012/

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL MIDNIGHT CST
/1 AM EST/ TONIGHT...

A WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL MIDNIGHT CST
/1 AM EST/ TONIGHT. 

* TIMING...SNOW WILL CONTINUE INTO THE EVENING HOURS.

* ACCUMULATIONS...STORM TOTAL SNOWFALL OF 4 TO 7 INCHES CAN BE 
  EXPECTED. 

* HAZARDS...SNOWFALL WILL CONTINUE TO TAPER OFF OVER THE NEXT 
  FEW HOURS...BUT LIGHT WINDS MAY CAUSE SOME BLOWING AND 
  DRIFTING OF THE FRESHLY FALLEN SNOW. 

* IMPACTS...TRAVEL MAY REMAIN DIFFICULT UNTIL ROAD CREWS CAN 
  CLEAR ALL ROADWAYS. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY FOR SNOW MEANS THAT PERIODS OF SNOW
WILL CAUSE PRIMARILY TRAVEL DIFFICULTIES. BE PREPARED FOR SNOW
COVERED ROADS AND LIMITED VISIBILITIES...AND USE CAUTION WHILE
DRIVING.

&&

$$

SHEA

What forecasters said that day

The local office's own words before this winter storm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Chicago, IL wrote its last area forecast discussion before this winter storm warning went out at Jan 19, 8:26 PM CST, 1 hour earlier.

Area forecast discussion, Jan 19, 8:26 PM CST, 1 hour before
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
826 PM CST THU JAN 19 2012

.DISCUSSION...
223 PM CST

SHORT TERM (THIS EVENING AND TONIGHT)...

CLEARING SKIES AND COLD ADVECTION WILL DRIVE DOWN TEMPERATURES
THIS EVENING INTO THE OVERNIGHT AS TRANSIENT HIGH MOVES ACROSS THE
AREA ALLOWING FOR STRONG RADIATIONAL COOLING SETUP. TEMPERATURES
WILL FALL TO NEAR 0F OR SLIGHTLY NEGATIVE... COLDEST WEST OF THE
FOX RIVER VALLEY WHERE TEMPERATURES MAY BOTTOM OUT -5F TO -10F.
PRESSURE GRADIENT BEGINS ENCROACHING INTO THE WEST IN THE PREDAWN
HOURS AND WILL MAKE TEMPERATURES FEEL EVEN COLDER AS A SLIGHT
BREEZE WILL CAUSE WIND CHILL VALUES TO DROP TO -10F TO NEAR -20F
ACROSS THE NORTHWEST QUADRANT OF THE CWA.

BMD

STORM TERM (FRIDAY AND FRIDAY NIGHT)...

ALL SYSTEMS STILL GO FOR A RESPECTABLE SNOW EVENT FRIDAY INTO FRIDAY
EVENING ACROSS ABOUT THE NORTHERN 2/3RDS OF THE CWA...UNFORTUNATELY
WHAT TO DO WITH HEADLINES IS LESS STRAIGHT FORWARD.

WATER VAPOR IMAGERY THIS AFTERNOON SHOWS A FAIRLY IMPRESSIVE
SHORTWAVE TROUGH HAS MOVED ONSHORE INTO NORTHERN CA/PAC NW WITH
ASSOCIATED 90KT+ 300MB JET STREAK. THIS SYSTEM IS PROGGED TO
TRANSLATE RAPIDLY EASTWARD THE NEXT 24-36 HOURS MOVING INTO THE
PLAINS BY 12Z FRIDAY AND EVENTUALLY SHEARING EAST INTO THE EASTERN
GREAT LAKES BY 12Z SATURDAY. GUIDANCE SUGGESTS ONLY A WEAK SURFACE
REFLECTION WILL DEVELOP AND TRACK WELL SOUTH OF OUR AREA. FORCING
FOR ASCENT LOCALLY WILL BE ALMOST ENTIRELY DRIVEN BY WARM AIR
ADVECTION/ISENTROPIC ASCENT WHICH WILL INCREASE AS LOW/MID LEVEL
FLOW BACKS/INCREASES IN ADVANCE OF THE WAVE. MODELS DO SUGGEST THAT
THERE WILL ALSO BE SOME WEAK JET COUPLING BETWEEN DEPARTING POLAR
JET AND PACIFIC STREAK STREAK PROVIDING FOR SOME ADDED EXHAUST
FURTHER SUPPORTING A PERIOD OF FAIRLY STRONG/DEEP ASCENT.

FORECAST SOUNDINGS FROM VARIOUS MODELS CONTINUE TO SHOW A DEEP
ISOTHERMAL LAYER HOVERING AROUND -10C. HOWEVER...FORECAST TIME
HEIGHT CROSS SECTIONS DO SUGGEST THAT UVVS WILL BE STRONG WITHIN THE
DENDRITIC GROWTH ZONE BETWEEN ROUGHLY 600-500MB WITH FAIRLY LIGHT
WINDS ALSO TENDING TO FAVOR HIGHER THAN AVERAGE SNOW TO LIQUID
RATIOS. ADMITTEDLY OUR SKILL IN PREDICTING SNOW:LIQUID RATIOS IS
LOW...BUT THIS EVENT DOES APPEAR TO HAVE THE LOOKS OF A HIGHER RATIO
EVENT. OTHER THAN THE VARIOUS WRF AND HI-RES MESOSCALE
MODELS...FORECAST MAX QPF HAS REMAINED CONSISTENTLY BETWEEN
0.35-0.50" WITHIN THE BAND OF HEAVIEST SNOW WHICH IS STILL LOOKING
TO SET-UP OVER FAR NORTHERN ILLINOIS.

HAVE BEEN HEMMING AND HAWING ALL MORNING LONG TRYING TO DECIDED
WHAT TO DO WITH THE ONGOING WINTER STORM WATCH. OVERALL...THIS
SYSTEM REALLY HAS THE LOOKS OF A SOLID ADVISORY EVENT AS IT IS A
LOW AMPLITUDE OPEN WAVE THAT IS EVEN DAMPENING SOMEWHAT AS IT
MOVES VERY QUICKLY EASTWARD. MANY OF THE HIGHER-RES WRFS CONTINUE
TO SPIT OUT HIGHER QPFS AND AM FAIRLY CONFIDENT THAT THESE NUMBERS
ARE TOO HIGH. PROBABLY THE BIGGEST WILD CARD WHICH COULD
POTENTIALLY PUSH SOME AREAS OVER THE EDGE INTO WARNING CRITERIA IS
THE SNOW:LIQUID RATIOS. HAVE GENERALLY GONE WITH 12-15:1 RATIOS IN
THE GRIDS NORTH OF I-80...WHICH SHOULD THESE TURN OUT TO BE TOO
CONSERVATIVE COULD RESULT IN SOME AREAS EXCEEDING 6 INCHES...BUT
THIS WILL LIKELY BE MORE OF A NOW-CASTING SHORT-FUSED UPGRADE TYPE
ISSUE.

AS ALLUDED TO IN THE BRIEF LATE MORNING AFD UPDATE THERE LOOKS TO BE
A VERY SHARP CUT OFF TO THE PRECIP ALONG THE SOUTHERN EDGE. FAR
SOUTHERN PORTIONS OF THE CWA WILL LIKELY REMAIN GENERALLY DRY
THROUGH THE DAY TOMORROW WITH A TIGHT GRADIENT BETWEEN ADVISORY
CRITERIA SNOWFALL AND LITTLE IF ANY ACCUMULATION. GRADIENT IN THE
CURRENT SNOW GRIDS AND FORECAST SNOW GRAPHICS IS LIKELY TOO BAGGY
BUT ABOUT AS REASONABLE OF A REPRESENTATION AS IS POSSIBLE AT THIS
DISTANCE.

IZZI

LONG TERM (SATURDAY THROUGH THURSDAY)...

SATURDAY...NORTHEAST BOUNDARY LAYER FLOW AND NEAR DRY ADIABATIC
LAPSE RATES WILL DRIVE A CHANCE FOR LAKE EFFECT SHOWERS INLAND FROM
THE ILLINOIS COASTAL AREAS. INVERSION HEIGHTS WILL BE A PROHIBITIVE
FACTOR IN DEEP DEVELOPMENT WITH A SHARP INVERSION AROUND 3500-4000
FEET SATURDAY MORNING DROPPING THROUGH THE DAY AS WINDS GRADUALLY
BACK TO THE WEST AND SOUTHWEST WITH WARM ADVECTION ALOFT. MAY JUST
BE DEEP ENOUGH FOR SOME LAKE EFFECT SNOW SHOWERS TO FORM BUT NOT
DEEP ENOUGH FOR SIGNIFICANT ACCUMULATING SNOWFALL OVER THE
AREA...THUS WILL MAINTAIN LOW CHANCE POPS FOR THE CHICAGO AREA ON
SATURDAY.

SATURDAY NIGHT THROUGH MONDAY...WARM ADVECTION RAMPS UP SATURDAY
NIGHT AND SUNDAY AS 50+ KT LOW LEVEL JET DEVELOPS. H85 TEMPS SURGE
TO 7-8C PER ECMWF WITH 10-11C OVER SOME AREAS PER GFS/NAM. THIS IS
AHEAD OF DEEP LOW MOVING OUT OF THE CENTRAL PLAINS TOWARDS THE
WESTERN GREAT LAKES REGION. STRONG VORT BEGINS TO TAKE ON NEGATIVE
TILT AS IT MOVES ACROSS MISSISSIPPI RIVER SUNDAY EVENING. ISENTROPIC
ASCENT ACROSS SHALLOW MOISTURE PROFILE WOULD INDICATE POTENTIAL FOR
DRIZZLE DEVELOPING EARLY IN THE DAY ON SUNDAY...AND DEPENDING ON HOW
QUICKLY SURFACE TEMPERATURES WARM AND THE AIR ABOVE
SATURATES...COULD BE LOOKING AT A WINDOW OF FREEZING DRIZZLE OR
LIGHT FREEZING RAIN SUNDAY MORNING BEFORE SURFACE TEMPERATURES WARM
ABOVE FREEZING LATE SUNDAY MORNING. ECMWF/GFS SHOW 50F DEWPOINTS
PUSHING INTO THE SOUTHERN CWA WHICH WILL DRIVE UP TEMPERATURES AND
COULD CAUSE AREAS OF FOG/DENSE FOG AS IT EATS AWAY AT LINGERING
SNOWPACK. COLD FRONT THEN SWEEPS ACROSS THE AREA SUNDAY NIGHT WITH
PRECIPITATION CHANGING BACK OVER TO SNOW FOR PART OF MONDAY. LOOKS
AS IF A GOOD MAJORITY OF THE PRECIP WILL FALL IN THE FORM OF RAIN
SUNDAY EVENING AND AM NOT TOO CONCERNED ABOUT SIGNIFICANT SNOWFALL
ACCUMULATIONS SUNDAY NIGHT INTO MONDAY AT THIS POINT. REGARDING
TEMPERATURES...NOT PARTICULARLY CONFIDENT ON TEMPERATURES FOR SUNDAY
BUT COULD SEE TEMPERATURES HIGHER THAN FORECAST IF SNOWPACK MELTS
QUICKLY. DID BUMP UP TEMPERATURES ACROSS AREAS SOUTH OF I-80 WHICH
SHOULD HAVE LITTLE IF ANY SNOWPACK BY THAT POINT.

NEXT WEEK...PROGRESSIVE PATTERN WILL CONTINUE INTO THE MIDDLE OF NEXT
WEEK WITH PERHAPS A BRIEF RESPITE FROM THE WEATHER TUESDAY BEFORE
ANOTHER SYSTEM IMPACTS THE REGION ON WEDNESDAY. UNFORTUNATELY...
THERE IS HUGE AMOUNT OF UNCERTAINTY CROPPING UP IN ENSEMBLES OVER
THE EXTENDED WITH NO CLEARCUT SOLUTIONS...SO WILL NOT GO TOO MUCH IN
DEPTH AT THIS POINT UNTIL THE SIGNALS BECOME STRONGER AND WENT WITH
MODEL CONSENSUS BLENDS IN THE EXTENDED.

BMD

&&

.AVIATION...

//ORD AND MDW CONCERNS...UPDATED 02Z...

 * NO CONCERNS OVERNIGHT
 * SNOW DEVELOPING TOMORROW MORNING
 * DEGRADATION TO CONDITIONS THROUGH THE DAY ON THURSDAY
 * IFR/LIFR CIGS/VIS POSSIBLE IN SN/+SN

SHEA

//DISCUSSION...UPDATED 00Z...

BUILDING SURFACE HIGH WILL ALLOW WINDS AT ALL TERMINALS TO BECOME
LIGHT AND VARIABLE LATER THIS EVENING UNDER PRIMARILY CLEAR SKIES.
FOCUS THEN TURNS TOWARDS AN APPROACHING SYSTEM TOMORROW MORNING.
LIGHT SNOW SHOWERS EXPECTED TO BEGIN IN THE LATE MORNING
HOURS...WITH HEAVIER SNOW TO FOLLOW INTO THE AFTERNOON. CIGS/VIS
SHOULD QUICKLY LOWER THROUGH IFR AND DEPENDING ON HOW HEAVY THE
SNOW BECOMES...LIFR CIGS AND VLIFR VIS ARE POSSIBLE ESPECIALLY
DURING THE AFTERNOON HOURS AND THROUGH THE EVENING .

SHEA

//ORD AND MDW CONFIDENCE...UPDATED 02Z...

 * HIGH CONFIDENCE THROUGH THE OVERNIGHT HOURS
 * MODERATE CONFIDENCE PRECIP TIMING
 * HIGH IN CONDITIONS FALLING TO IFR
 * MODERATE CONFIDENCE IN CONDITIONS DETERIORATING LOWER

SHEA

//OUTLOOK FOR ORD/MDW FOR 12Z SATURDAY-12Z THURSDAY...UPDATED 00Z...

 * SATURDAY...CHANCE OF SNOW SHOWERS OR FLURRIES. MVFR POSSIBLE.
 * SUNDAY...CHANCE OF RAIN OR SNOW. MVFR POSSIBLE.
 * MONDAY...SLIGHT CHANCE OF SNOW SHOWERS.
 * TUESDAY...VFR.
 * WEDNESDAY...CHANCE OF RAIN OR SNOW.

SHEA

&&

.MARINE...
218 PM CST

AS THE LOW WHICH BROUGHT THE GALES AND FREEZING SPRAY TO LAKE
MICHIGAN GETS SCOOTED AWAY BY HIGH PRESSURE...A RELATIVELY QUIET 48
HOURS ARE UPCOMING FOR THE LAKE. LAKE GENERATED SNOW SHOWERS WILL
CONTINUE OVER THE EASTERN HALF OF THE LAKE THROUGH THIS EVENING
BEFORE ENDING...AS WILL SMALL CRAFT CONDITIONS ALONG THE SOUTHERN
AND EASTERN SHORE. SURFACE HIGH PRESSURE OVER THE LAKE FRIDAY
INTO SATURDAY WILL MAKE WINDS VARIABLE AT TIMES...ESPECIALLY OVER
THE CENTRAL AND SOUTH. LAKE ENHANCED SNOW SHOWERS ARE EXPECTED
AGAIN ON SATURDAY INTO THE ILLINOIS NEAR SHORE AREAS. A DEEPER
AND MORE AMPLIFIED LOW PRESSURE SYSTEM IS EXPECTED TO CROSS FROM
SOUTHWEST TO NORTHEAST OVER THE LAKE DURING LATE SUNDAY NIGHT INTO
MONDAY AS THE WEATHER PATTERN REMAINS PROGRESSIVE. THIS WILL
OVERSPREAD A TIGHT PRESSURE GRADIENT ACROSS THE LAKE AND STRONGER
WINDS ALOFT. IT IS TOO EARLY TO TELL WHAT MAGNITUDE OF THESE WINDS
WILL MAKE IT DOWN FOR POSSIBLE GALES ON SUNDAY NIGHT THROUGH
MONDAY.

MTF

&&

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...WINTER WEATHER ADVISORY...ILZ003-ILZ004-ILZ008-ILZ010-ILZ011...6
     AM FRIDAY TO 9 PM FRIDAY.

     WINTER WEATHER ADVISORY...ILZ005-ILZ006-ILZ012-ILZ013-ILZ014-
     ILZ020-ILZ022...9 AM FRIDAY TO MIDNIGHT SATURDAY.

IN...WINTER WEATHER ADVISORY...INZ001-INZ002...9 AM FRIDAY TO
     MIDNIGHT SATURDAY.

LM...SMALL CRAFT ADVISORY...NEARSHORE GARY TO MICHIGAN CITY IN UNTIL 4 AM FRIDAY.

&&
Hazardous weather outlook, Jan 19, 3:11 PM CST, 6 hours 15 minutes before
HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
311 PM CST THU JAN 19 2012

ILZ003>006-008-010>014-019>023-032-033-039-INZ001-002-010-011-019-
202115-
WINNEBAGO-BOONE-MCHENRY-LAKE ILLINOIS-OGLE-LEE-DE KALB-KANE-
DUPAGE-COOK-LA SALLE-KENDALL-GRUNDY-WILL-KANKAKEE-LIVINGSTON-
IROQUOIS-FORD-LAKE INDIANA-PORTER-NEWTON-JASPER-BENTON-
311 PM CST THU JAN 19 2012 /411 PM EST THU JAN 19 2012/

THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTH CENTRAL ILLINOIS...
NORTHEAST ILLINOIS AND NORTHWEST INDIANA.

.DAY ONE...THIS AFTERNOON AND TONIGHT.

TEMPERATURES ARE EXPECTED TO FALL BELOW ZERO TONIGHT WEST OF THE
FOX RIVER VALLEY WITH WIND CHILLS OF -10F TO -20F POSSIBLE IN THE
PREDAWN HOURS.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY.

ACCUMULATING SNOW OF 3 TO 6 INCHES IS POSSIBLE OVER PORTIONS OF
NORTHERN ILLINOIS AND NORTHWEST INDIANA FRIDAY AND FRIDAY NIGHT
WITH THE HIGHEST AMOUNTS EXPECTED ALONG AND NORTH OF THE
INTERSTATE 80 CORRIDOR.

ON SUNDAY MORNING...THERE IS A CHANCE OF FREEZING DRIZZLE ACROSS
PORTIONS OF NORTHERN ILLINOIS AND NORTHWEST INDIANA.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL NOT BE NECESSARY THROUGH TONIGHT.

&&

COMPLETE FORECAST INFORMATION IS AVAILABLE ON THE NWS CHICAGO
WEBPAGE: WEATHER.GOV/CHICAGO

LMZ740>745-202115-
WINTHROP HARBOR TO WILMETTE HARBOR-
WILMETTE HARBOR TO NORTHERLY ISLAND-
NORTHERLY ISLAND TO CALUMET HARBOR-CALUMET HARBOR TO GARY-
GARY TO BURNS HARBOR-BURNS HARBOR TO MICHIGAN CITY-
311 PM CST THU JAN 19 2012

THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE ILLINOIS NEARSHORE
WATERS OF LAKE MICHIGAN AND THE INDIANA NEARSHORE WATERS OF LAKE
MICHIGAN.

.DAY ONE...THIS AFTERNOON AND TONIGHT.

WAVES HAZARDOUS TO SMALL CRAFT ARE EXPECTED THROUGH THIS EVENING
FOR THE ILLINOIS NEARSHORE WATERS AND THROUGH TONIGHT FOR THE
INDIANA NEARSHORE WATERS.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY.

WINDS AND WAVES HAZARDOUS TO SMALL CRAFT ARE EXPECTED ACROSS THE
INDIANA AND ILLINOIS NEARSHORE WATERS SATURDAY NIGHT THROUGH
MONDAY NIGHT.

&&

COMPLETE FORECAST INFORMATION IS AVAILABLE ON THE NWS CHICAGO
WEBPAGE: WEATHER.GOV/CHICAGO

LMZ080-261-362-364-366-563-565-567-669-671-673-675-777-779-868-
870-872-874-876-878-202115-
LAKE MICHIGAN FROM MICHIGAN CITY IN TO ST. JOSEPH MI 5 NM
OFFSHORE TO MID LAKE-
LAKE MICHIGAN FROM SEUL CHOIX POINT TO ROCK ISLAND PASSAGE 5 NM
OFFSHORE TO MID LAKE-
LAKE MICHIGAN SOUTH OF A LINE FROM SEUL CHOIX POINT TO THE
MACKINAC BRIDGE AND NORTH OF A LINE FROM CHARLEVOIX MI TO SOUTH
FOX ISLAND 5 NM OFFSHORE-
LAKE MICHIGAN FROM CHARLEVOIX TO POINT BETSIE MI 5 NM OFFSHORE TO
MID LAKE-
LAKE MICHIGAN FROM POINT BETSIE TO MANISTEE MI 5 NM OFFSHORE TO
MID LAKE-
LAKE MICHIGAN FROM ROCK ISLAND PASSAGE TO STURGEON BAY WI-
LAKE MICHIGAN FROM STURGEON BAY TO TWO RIVERS WI 5 NM OFFSHORE TO
MID LAKE-
LAKE MICHIGAN FROM TWO RIVERS TO SHEBOYGAN WI 5 NM OFFSHORE TO
MID LAKE-
LAKE MICHIGAN FROM SHEBOYGAN TO PORT WASHINGTON WI 5 NM OFFSHORE
TO MID LAKE-
LAKE MICHIGAN FROM PORT WASHINGTON TO NORTH POINT LIGHT WI 5 NM
OFFSHORE TO MID LAKE-
LAKE MICHIGAN FROM NORTH POINT LIGHT TO WIND POINT WI 5 NM
OFFSHORE TO MID LAKE-
LAKE MICHIGAN FROM WIND POINT WI TO WINTHROP HARBOR IL 5 NM
OFFSHORE TO MID LAKE-
LAKE MICHIGAN FROM WINTHROP HARBOR TO WILMETTE HARBOR IL 5 NM
OFFSHORE TO MID LAKE-
LAKE MICHIGAN FROM WILMETTE HARBOR IL TO MICHIGAN CITY IN 5 NM
OFFSHORE TO MID LAKE-
LAKE MICHIGAN FROM PENTWATER TO MANISTEE MI 5 NM OFFSHORE TO MID
LAKE-
LAKE MICHIGAN FROM WHITEHALL TO PENTWATER MI 5 NM OFFSHORE TO MID
LAKE-
LAKE MICHIGAN FROM GRAND HAVEN TO WHITEHALL MI 5 NM OFFSHORE TO
MID LAKE-
LAKE MICHIGAN FROM HOLLAND TO GRAND HAVEN MI 5 NM OFFSHORE TO MID
LAKE-
LAKE MICHIGAN FROM SOUTH HAVEN TO HOLLAND MI 5 NM OFFSHORE TO MID
LAKE-
LAKE MICHIGAN FROM ST. JOSEPH TO SOUTH HAVEN MI 5 NM OFFSHORE TO
MID LAKE-
311 PM CST THU JAN 19 2012

THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE OPEN WATERS OF LAKE
MICHIGAN.

.DAY ONE...THIS AFTERNOON AND TONIGHT.

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY.

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

&&

COMPLETE FORECAST INFORMATION IS AVAILABLE ON THE NWS CHICAGO
WEBPAGE: WEATHER.GOV/CHICAGO

BMD

In the hours before

Local storm report, Jan 19, 4:09 PM CST, 5 hours 17 minutes before
PRELIMINARY LOCAL STORM REPORT...SUMMARY
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
409 PM CST THU JAN 19 2012

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1035 AM     SNOW             STREATOR                41.13N 88.83W
01/19/2012  E2.0 INCH        LA SALLE           IL   FIRE DEPT/RESCUE

1035 AM     SNOW             PONTIAC                 40.88N 88.64W
01/19/2012  E2.3 INCH        LIVINGSTON         IL   LAW ENFORCEMENT

1035 AM     SNOW             DWIGHT                  41.10N 88.42W
01/19/2012  E2.0 INCH        LIVINGSTON         IL   FIRE DEPT/RESCUE

1040 AM     SNOW             KANKAKEE                41.12N 87.86W
01/19/2012  M2.0 INCH        KANKAKEE           IL   TRAINED SPOTTER

            STORM TOTAL. SOME BLOWING AND DRIFTING. JUST SNOW
            FLURRIES NOW.

1100 AM     SNOW             ENE PEOTONE             41.33N 87.80W
01/19/2012  M1.0 INCH        WILL               IL   COCORAHS

            STORM TOTAL. SNOW HAS ENDED. WATER EQUIVALENT 0.08
            INCHES.

&&

RATZER

The office that day

Everything else NWS Chicago, IL issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jan 20, 3:07 PM CSTGale WatchLOT25 hr

Nearby

Winter Storm Warnings in Illinois, 2012Every winter storm warning in 2012

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.