HYDROLOGIC OUTLOOK
Issue Date: 902 PM CST TUE DEC 22 2009
Expiration: 915 AM CST WED DEC 23 2009

/1002 PM EST TUE DEC 22 2009/
...RENEWED RISES ON AREA RIVERS POSSIBLE LATER THIS WEEK...
A VERY STRONG LOW WILL MOVE INTO NORTHEAST IOWA BY FRIDAY
MORNING. THIS WILL BRING A MIXTURE OF PRECIPITATION
TONIGHT...WEDNESDAY AND THURSDAY INTO NORTHERN ILLINOIS AND
NORTHWEST INDIANA. THE PRECIPITATION WILL BEGIN AS SNOW AND SLEET
OVERNIGHT AND WILL CHANGE TO FREEZING DRIZZLE. WE EXPECT FREEZING
RAIN WEDNESDAY NIGHT AND EARLY THURSDAY MORNING. THEN...RAIN WILL
FALL OVER THE AREA THURSDAY. THERE IS SNOW ON THE GROUND AND THE
ADDITIONAL 1 TO 2 INCHES OF RAIN WITH SNOWMELT WILL ADD SIGNIFICANT
RUNOFF TO AREA RIVERS. SOME LOCAL RIVERS AND CREEKS MAY RISE
THURSDAY AND FRIDAY.
SNOW DEPTHS WERE GREATEST WITHIN PORTIONS OF THE ROCK...UPPER
FOX...AND UPPER DES PLAINES RIVER BASINS WHERE DEPTHS WERE BETWEEN 4
AND 8 INCHES. WATER EQUIVALENT OF THE SNOWPACK IN THOSE AREAS WAS
AROUND 1 INCH. FURTHER SOUTH...SNOW DEPTHS WERE BETWEEN 2 AND 4
INCHES WITH WATER EQUIVALENTS GENERALLY BELOW ONE HALF INCH.
REPORTED FROST DEPTHS WERE BETWEEN 2 AND 4 INCHES. ALTHOUGH RIVERS
WERE CURRENTLY BELOW FLOOD STAGE...FLOWS WERE SLIGHTLY ABOVE
NORMAL.
A COMBINATION OF HEAVY RAIN AND SNOWMELT OVER FROZEN GROUND WOULD
RESULT IN RISES ON AREA STREAMS WITH SOME RISES POSSIBLY ABOVE FLOOD
STAGE.
RESIDENTS IN LOW LYING FLOOD PRONE AREAS ALONG AREA RIVERS AND
CREEKS SHOULD CONTINUE TO MONITOR THIS DEVELOPING WEATHER SYSTEM.
$$

FLOOD WATCH
Issue Date: 345 AM CST WED DEC 23 2009
Expiration: 600 AM CST FRI DEC 25 2009

...HEAVY RAIN AND FLOODING POSSIBLE THURSDAY AFTERNOON THROUGH
FRIDAY MORNING...
.A DEVELOPING WINTER STORM OVER THE SOUTHERN PLAINS WILL MOVE
NORTH TO IOWA BY FRIDAY MORNING. AFTER A PERIOD OF WINTRY
PRECIPITATION WEDNESDAY AFTERNOON INTO THURSDAY MORNING...WARM
MOIST AIR WILL SPREAD NORTH ACROSS THE AREA WITH PERIODS OF
HEAVY RAIN EXPECTED THURSDAY AFTERNOON AND THURSDAY NIGHT.
ILZ003>006-008-010>014-019>023-032-033-039-INZ001-002-010-011-019-
231745-
/O.NEW.KLOT.FA.A.0003.091224T1800Z-091225T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
WINNEBAGO-BOONE-MCHENRY-LAKE IL-OGLE-LEE-DE KALB-KANE-DUPAGE-COOK-
LA SALLE-KENDALL-GRUNDY-WILL-KANKAKEE-LIVINGSTON-IROQUOIS-FORD-
LAKE IN-PORTER-NEWTON-JASPER-BENTON-
INCLUDING THE CITIES OF...ROCKFORD...BELVIDERE...WOODSTOCK...
WAUKEGAN...OREGON...DIXON...DEKALB...AURORA...WHEATON...CHICAGO...
OTTAWA...OSWEGO...MORRIS...JOLIET...KANKAKEE...PONTIAC...
WATSEKA...PAXTON...GARY...VALPARAISO...MOROCCO...RENSSELAER...
FOWLER
345 AM CST WED DEC 23 2009 /445 AM EST WED DEC 23 2009/
...FLOOD WATCH IN EFFECT FROM THURSDAY AFTERNOON THROUGH LATE
THURSDAY NIGHT...
THE NATIONAL WEATHER SERVICE IN CHICAGO HAS ISSUED A
* FLOOD WATCH FOR PORTIONS OF ILLINOIS AND INDIANA...INCLUDING
THE FOLLOWING AREAS...IN ILLINOIS...BOONE...COOK...DE KALB...
DUPAGE...FORD...GRUNDY...IROQUOIS...KANE...KANKAKEE...
KENDALL...LA SALLE...LAKE IL...LEE...LIVINGSTON...MCHENRY...
OGLE...WILL AND WINNEBAGO. IN INDIANA...BENTON...JASPER...LAKE
IN...NEWTON AND PORTER.
* FROM THURSDAY AFTERNOON THROUGH LATE THURSDAY NIGHT.
* HEAVY RAIN IS EXPECTED TO DEVELOP ACROSS NORTHERN ILLINOIS AND
NORTHWEST INDIANA BY THURSDAY AFTERNOON AND CONTINUE THROUGH
EARLY FRIDAY MORNING. STORM TOTAL RAINFALL AMOUNTS OF 1 TO 2
INCHES WILL BE COMMON. SOME AREAS MAY RECEIVE AS MUCH AS 3
INCHES BY FRIDAY MORNING.
* THE DEPTH OF THE CURRENT SNOW PACK RANGES FROM 5 TO 8 INCHES
OVER NORTHWEST ILLINOIS TO 1 TO 3 INCHES ACROSS NORTHWEST
INDIANA. AS THIS SNOW MELTS...COMBINED WITH THE EXPECTED HEAVY
RAIN...AND FROZEN GROUND CONDITIONS...RAPID RUNOFF AND RISES ON
AREA RIVERS ARE EXPECTED. SOME RIVERS MAY REACH OR EXCEED FLOOD
STAGE. FLOODING OF LOW LYING AND FLOOD PRONE AREAS WILL ALSO BE
POSSIBLE.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
A FLOOD WATCH MEANS THERE IS A POTENTIAL FOR FLOODING BASED ON
CURRENT FORECASTS.
YOU SHOULD MONITOR LATER FORECASTS AND BE ALERT FOR POSSIBLE
FLOOD WARNINGS. THOSE LIVING IN AREAS PRONE TO FLOODING SHOULD BE
PREPARED TO TAKE ACTION SHOULD FLOODING DEVELOP.
$$

HAZARDOUS WEATHER OUTLOOK
Issue Date: 430 PM CST TUE DEC 22 2009
Expiration: 415 PM CST WED DEC 23 2009

/511 PM EST TUE DEC 22 2009/
THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTH CENTRAL ILLINOIS...
NORTHEAST ILLINOIS AND NORTHWEST INDIANA.
.DAY ONE...TONIGHT.
SCATTERED LIGHT SNOW SHOWERS WILL CONTINUE THROUGH EARLY EVENING ACROSS
AREAS TO THE NORTH AND NORTHEAST OF A LINE FROM ROCHELLE TO VALPARAISO.
AREAS OF FREEZING DRIZZLE ARE EXPECTED TO DEVELOP ACROSS AREAS TO
THE SOUTH OF INTERSTATE 80 LATE THIS EVENING THROUGH THE
OVERNIGHT HOURS. UNTREATED AREA ROADS MAY CONTINUE TO BE SLIPPERY
TONIGHT.
.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY.
FREEZING DRIZZLE WILL CONTINUE ACROSS AREAS ALONG AND TO THE SOUTH
OF INTERSTATE 80 THROUGH LATE MORNING. AT THE SAME TIME...A
STRENGTHENING STORM SYSTEM OVER THE SOUTHERN PLAINS WILL RESULT IN
A MORE SUBSTANTIAL AREA OF PRECIPITATION MOVING NORTH ACROSS THE
AREA BEGINNING DURING THE DAY WEDNESDAY. THIS WILL RESULT IN A
PERIOD OF FREEZING RAIN MIXED WITH SNOW AND SLEET OVERSPREADING
THE AREA WEDNESDAY...BEFORE PRECIPITATION TURNS TO ALL FREEZING
RAIN LATER IN THE AFTERNOON WEDNESDAY AND WEDNESDAY EVENING.
SURFACE TEMPERATURES ARE THEN EXPECTED TO GRADUALLY WARM ABOVE
FREEZING ON THURSDAY...RESULTING IN A CHANGE OVER TO ALL RAIN. COLDER
AIR WILL THEN CIRCULATE AROUND THE STORM CENTER ALLOWING
PRECIPITATION TO CHANGE BACK TO LIGHT SNOW OR SNOW SHOWERS ON
CHRISTMAS DAY...WITH PERIODS OF LIGHT SNOW CONTINUING INTO SUNDAY
AS THE LOW CENTER DRIFTS OFF ACROSS THE UPPER MIDWEST.
A WINTER STORM WATCH AND WINTER WEATHER ADVISORY IS NOW IN EFFECT
FOR PORTIONS OF THE OUTLOOK AREA. PLEASE REFERENCE THE LATEST
WINTER WEATHER STATEMENTS FROM THE NATIONAL WEATHER SERVICE FOR
THE LATEST FORECAST INFORMATION...AS WELL AS ANY ADDITIONAL
WATCHES...WARNINGS...OR ADVISORIES THAT MAY BE ISSUED.
THIS STORM SYSTEM HAS THE POTENTIAL TO IMPACT TRAVEL DURING THE
CHRISTMAS HOLIDAY PERIOD. PERSONS PLANNING TRAVEL ACROSS THE
MIDWEST BETWEEN WEDNESDAY AND SATURDAY SHOULD MONITOR FURTHER
FORECASTS AND STATEMENTS FOR THE LATEST INFORMATION ON THIS
DEVELOPING WINTER STORM.
.SPOTTER INFORMATION STATEMENT...
SPOTTER ACTIVATION WILL NOT BE NECESSARY THROUGH TONIGHT...
HOWEVER SPOTTERS ARE ENCOURAGED TO REPORT SNOWFALL TOTALS TO THE
NATIONAL WEATHER SERVICE CHICAGO.
&&
COMPLETE FORECAST INFORMATION IS AVAILABLE ON THE NWS CHICAGO
WEBPAGE: WEATHER.GOV/CHICAGO
$$

WINTER STORM WATCH
Issue Date: 1131 AM CST TUE DEC 22 2009
Expiration: 1200 PM CST THU DEC 24 2009

...WINTER STORM TO BRING SLEET AND FREEZING RAIN TO AREA WEDNESDAY
INTO THURSDAY...
.LOW PRESSURE ASSOCIATED WITH A DEVELOPING WINTER STORM WILL LIFT
FROM THE SOUTHERN PLAINS INTO THE MISSISSIPPI VALLEY THROUGH
THURSDAY. WHILE THE TRACK OF THE STORM WILL KEEP HEAVY SNOWS WEST
OF THE AREA...WARM MOIST AIR FLOWING NORTH ACROSS NORTHERN ILLINOIS
AND INDIANA WILL RIDE UP OVER COLD AIR NEAR THE GROUND...AND IS
EXPECTED TO RESULT IN A PERIOD OF SLEET AND FREEZING RAIN FROM
WEDNESDAY INTO THURSDAY MORNING. FREEZING RAIN MAY RESULT IN UP
TO A QUARTER INCH OF ICE ACCUMULATION OVER PARTS OF THE WATCH AREA
ESPECIALLY LATE WEDNESDAY AND WEDNESDAY NIGHT. SURFACE
TEMPERATURES WILL THEN RISE ABOVE FREEZING FROM SOUTH TO NORTH BY
MIDDAY THURSDAY...WITH PRECIPITATION CHANGING TO RAIN OVER THE
AREA BY THURSDAY AFTERNOON.
ILZ003>006-008-010>014-019>023-INZ001-002-010-011-230145-
/O.NEW.KLOT.WS.A.0004.091223T1800Z-091224T1800Z/
WINNEBAGO-BOONE-MCHENRY-LAKE IL-OGLE-LEE-DE KALB-KANE-DUPAGE-COOK-
LA SALLE-KENDALL-GRUNDY-WILL-KANKAKEE-LAKE IN-PORTER-NEWTON-
JASPER-
INCLUDING THE CITIES OF...ROCKFORD...BELVIDERE...WOODSTOCK...
WAUKEGAN...OREGON...DIXON...DEKALB...AURORA...WHEATON...CHICAGO...
OTTAWA...OSWEGO...MORRIS...JOLIET...KANKAKEE...GARY...
VALPARAISO...MOROCCO...RENSSELAER
1131 AM CST TUE DEC 22 2009
...WINTER STORM WATCH IN EFFECT FROM WEDNESDAY AFTERNOON THROUGH
THURSDAY MORNING...
THE NATIONAL WEATHER SERVICE IN CHICAGO HAS ISSUED A WINTER STORM
WATCH...WHICH IS IN EFFECT FROM WEDNESDAY AFTERNOON THROUGH
THURSDAY MORNING.
* TIMING...LIGHT SLEET AND FREEZING RAIN WILL BEGIN DURING THE DAY
WEDNESDAY. HEAVIEST FREEZING RAIN IS EXPECTED FROM WEDNESDAY
EVENING INTO THURSDAY MORNING.
* ACCUMULATIONS...UP TO A QUARTER INCH OF ICE.
* HAZARDS...ACCUMULATION. SOME SLEET AND LIGHT SNOW MAY MIX AS
PRECIPITATION BEGINS ON WEDNESDAY.
* IMPACTS...GLAZING OF ROADWAYS...PARKING LOTS AND SIDEWALKS. THIS
WILL MAKE FOR HAZARDOUS TRAVEL ON UNTREATED SURFACES.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
A WINTER STORM WATCH MEANS THERE IS A POTENTIAL FOR SIGNIFICANT
SNOW...SLEET...OR ICE ACCUMULATIONS THAT MAY IMPACT TRAVEL.
CONTINUE TO MONITOR THE LATEST FORECASTS.
$$
RATZER