Flash Flood Warning 8, NWS Chicago, IL

151 
WGUS73 KLOT 182153
FFSLOT

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
453 PM CDT THU APR 18 2013

ILC031-037-043-063-089-091-093-099-103-105-197-INC089-190100-
/O.CON.KLOT.FF.W.0008.000000T0000Z-130419T0100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
KANE IL-KANKAKEE IL-KENDALL IL-LA SALLE IL-LIVINGSTON IL-WILL IL-
GRUNDY IL-DE KALB IL-DUPAGE IL-LEE IL-COOK IL-LAKE IN-
453 PM CDT THU APR 18 2013

...FLASH FLOOD WARNING REMAINS IN EFFECT FOR NORTHWESTERN LAKE...
COOK...SOUTHEASTERN LEE...DUPAGE...SOUTHERN DE KALB...GRUNDY...
WILL...NORTHWESTERN LIVINGSTON...LA SALLE...KENDALL...NORTHWESTERN
KANKAKEE AND KANE COUNTIES UNTIL 800 PM CDT...

EXTENSIVE FLOODING CONTINUES IN MANY LOCATIONS ACROSS THE WARNING 
AREA DUE TO HEAVY RAINFALL OVER THE PAST TWO DAYS. 

SOME LOCATIONS THAT WILL CONTINUE TO EXPERIENCE FLOODING INCLUDE... 
ADDISON...ALSIP...ARLINGTON HEIGHTS...AURORA...BARRINGTON... 
BATAVIA...BERWYN...BLUE ISLAND...BOLINGBROOK...BROOKFIELD... 
BURNHAM...BURR RIDGE...CALUMET CITY...CAROL STREAM AND 
CARPENTERSVILLE.


PRECAUTIONARY/PREPAREDNESS ACTIONS...

CONTINUED RUNOFF FROM THIS RAINFALL WILL CONTINUE TO CAUSE ELEVATED 
LEVELS ON SMALL CREEKS AND STREAMS...PONDING OF WATER ON 
ROADS...URBAN AREAS... HIGHWAYS... UNDERPASSES AND LOW LYING AREAS.

FLOODING OF SMALL CREEKS AND STREAMS...COUNTRY ROADS...AS WELL AS 
FARMLAND ALONG THE BANKS OF CREEKS AND STREAMS WILL CONTINUE.

DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE
ROADWAY. THE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO CROSS
SAFELY.

&&

LAT...LON 4111 8799 4112 8827 4078 8893 4092 8894
      4093 8905 4110 8905 4111 8917 4166 8920
      4216 8835 4215 8776 4208 8767 4184 8760
      4170 8751 4169 8742 4165 8742 4162 8730

$$

RATZER

241 
WGUS73 KLOT 190042
FFSLOT

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
742 PM CDT THU APR 18 2013

ILC031-037-043-063-089-091-093-099-103-105-197-INC089-190055-
/O.CAN.KLOT.FF.W.0008.000000T0000Z-130419T0100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
KANE IL-KANKAKEE IL-KENDALL IL-LA SALLE IL-LIVINGSTON IL-WILL IL-
GRUNDY IL-DE KALB IL-DUPAGE IL-LEE IL-COOK IL-LAKE IN-
742 PM CDT THU APR 18 2013

...THE FLASH FLOOD WARNING THAT WAS IN EFFECT FOR NORTHWESTERN
LAKE...COOK...SOUTHEASTERN LEE...DUPAGE...SOUTHERN DE KALB...
GRUNDY...WILL...NORTHWESTERN LIVINGSTON...LA SALLE...KENDALL...
NORTHWESTERN KANKAKEE AND KANE COUNTIES HAS BEEN REPLACED WITH A 
NEW FLOOD WARNING THAT EXTENDS THROUGH FRIDAY MORNING......


LAT...LON 4111 8799 4112 8827 4078 8893 4092 8894
      4093 8905 4110 8905 4111 8917 4166 8920
      4216 8835 4215 8776 4208 8767 4184 8760
      4170 8751 4169 8742 4165 8742 4162 8730

$$

RODRIGUEZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
1149 AM CDT THU APR 18 2013

.MESOSCALE DISCUSSION...
1148 AM CDT

MAJOR RIVER AND FLASH FLOOD EVENT UNDERWAY ACROSS NORTHERN
ILLINOIS. HAVE MADE SOME ADJUSTMENTS TO GOING FORECAST TO BACK OFF
ON INTENSITY RAINFALL SOME THIS AFTERNOON AND ALSO BACK OFF ON
SEVERE WEATHER THREAT.

RADAR AND SATELLITE IMAGERY SHOW WHAT APPEARS TO BE A CONVECTIVELY
ENHANCED VORT MAX LIFTING NORTHEAST INTO LOWER MICHIGAN LATE THIS
MORNING. ASSOCIATED QLCS HAS PUSHED EAST AND SOUTHEAST OF THE CWA
SHOVING THE EFFECTIVE FRONT SOUTHEAST WITH IT. SOME BREAK IN THE
TRAILING STRATIFORM RAIN OVER ABOUT THE NORTHWEST HALF OF THE CWA.
HOWEVER...WATER VAPOR IMAGERY SHOWS A COUPLE MORE APPARENT VORT
MAXIMA UPSTREAM WITH ONE OVER MISSOURI AND ANOTHER OVER EASTERN
OKLAHOMA.

AT THE SURFACE...MASS FIELDS WERE SIGNIFICANTLY DISRUPTED
BY MORNING CONVECTION...HOWEVER SFC LOW OVER SOUTHEAST IOWA IS
BEGINNING TO DEEPEN AND LIFT NORTHWARD. FAIRLY STRONG PRESSURE
FALLS UP TO 4MB/3HR ARE TAKING PLACE OVER THE REGION IN RESPONSE TO
THESE PRESSURE FALLS NOTED IN THE WIND FIELD WITH DEVELOPING
SOUTHERLY FLOW IN THE WAKE OF THE MORNING CONVECTION. GIVEN THE
ANTICIPATED CLOUD COVER...EVEN WITH A REBOUND IN TEMPS/DEWPOINTS
ACROSS THE AREA THIS AFTERNOON THINKING IT IS UNLIKELY THAT
ATMOSPHERE WILL BE ABLE TO SUFFICIENTLY RECOVER AND DESTABILIZE TO
SUPPORT SEVERE THUNDERSTORMS.

DESPITE THE REDUCED SEVERE THREAT...DO EXPECT RAINFALL TO RAMP UP
SOME THIS AFTERNOON AS MO VORT LIFTS NORTHEAST INTO THE CWA. THE
THREAT FOR ADDITIONAL HEAVIER RAINFALL LOOKS TO BE CONFINED TO AREAS
SOUTHEAST OF INTERSTATE 55...WHICH THANKFULLY LOOKS TO SPARE THE FOX
AND DES PLAINES RIVER BASINS FROM ADDITIONAL SIGNIFICANT RAINFALL.
GENERALLY THINKING FROM 18-06Z TODAY THAT RAINFALL AMOUNTS FROM THE
NORTHERN SUBURBS INTO NORTH CENTRAL ILLINOIS WILL BE LESS THAN A
QUARTER INCH...WITH POTENTIALLY A QUARTER TO HALF INCH MORE RAIN
ALONG THE I-55 CORRIDOR...AND POTENTIALLY AN ADDITIONAL ONE TO TWO
INCHES OVER FAR SOUTHEAST CWA.

IZZI

&&

.DISCUSSION...
338 AM CDT

THIS MORNING...
IR IMAGERY EARLY THIS MORNING DEPICTS A ROBUST ATMOSPHERIC RIVER OF
CONVECTION STRETCHING FROM THE SOUTHERN PLAINS NORTHEAST THROUGH THE
GREAT LAKES REGION. CLOUD TOPS BRIEFLY WARMED ACROSS PORTIONS OF
NORTHERN IL TO -55C...HOWEVER FURTHER UPSTREAM WITH THE NEXT WAVE OF
CONVECTION IN NORTHEAST MO CLOUD TOPS HAVE COOLED BACK TO -70 DEG C.
SFC OBSERVATIONS INDICATE THE BOUNDARY STRETCHED
ACROSS THE NORTHERN ROW OF COUNTIES IN IL...INTO CENTRAL IA. NORTH
OF THE BOUNDARY TEMPS REMAINED IN THE LOW/MID 40S...WHILE TO THE
SOUTH TEMPS HAVE RISEN INTO THE MID/UPR 50S. ACROSS CENTRAL IL TEMPS
HAVE RISEN FURTHER INTO THE MID/UPR 60S. ABUNDANT MOISTURE CONTINUES
TO STREAM NORTH INTO THE WARM SECTOR WITH DEW POINTS RANGING FROM
55-62 DEG. SFC ANALYSIS INDICATES PWAT VALUES IN THE WARM SECTOR TO
BE 1-1.5" THIS MORNING. REGIONAL RADAR SHOWS A CONTINUOUS CHANNEL OF
SHOWERS/THUNDERSTORMS STRETCHING FROM SOUTHWEST MO NORTHEAST INTO
NORTHERN IL. PERIODS OF RAINFALL HAVE BEEN HEAVY AT TIMES THROUGH
EARLY THIS MORNING...WITH LOCATIONS RECEIVING OVER 1-2".

DYNAMICS EARLY THIS MORNING WILL BECOME EVEN STRONGER WITH 0-3KM
BULK SHEAR VALUES NEARING 60KTS. SFC WINDS IN THE WARM SECTOR HAVE
ALREADY BEGUN TO BACK TO THE SOUTHEAST. IT DOESN'T APPEAR ANY BREAKS
IN THE CLOUD COVER WILL OCCUR EARLY THIS MORNING...NONETHELESS
HELICITY AND EFFECTIVE SHEAR WILL ONLY INCREASE THROUGH THE MORNING.
WITH THE NEXT WAVE PROGGED TO ARRIVE MID-MORNING...FEEL THAT THIS
WILL BE THE MORE FAVORED TIME FOR AN INCREASE IN THE CONVECTIVE
COVERAGE AND INTENSITY. THE SPC CONTINUES TO HAVE THE BULK OF
NORTHERN IL/NORTHWEST IN AT LEAST IN A SLIGHT RISK FOR SEVERE
WEATHER...WITH A PORTION OF NORTHWEST IN PROGGED FOR MODERATE RISK.
WITH THE TROUGH AXIS SLOWLY PIVOTING EAST ACROSS THE CENTRAL
PLAINS...THIS WILL HELP TO ENHANCE THE LOW-LEVEL JET OF 60 KTS OR
GREATER TO PUSH OVER THE CWFA. THUS IT APPEARS PERHAPS A FEW
DISCRETE STORMS COULD DEVELOP THIS MORNING...THE MAIN CONCERN IS
THAT A SQUALL LINE WITH DAMAGING WINDS WILL BEGIN TO TAKE SHAPE AND
SLIDE EAST TOWARDS THE CWFA MID/LATE MORNING.

THIS AFTERNOON...
500MB TROUGH AXIS WILL APPROACH THE CENTRAL PLAINS MIDDAY WITH A
COUPLE AREAS OF LOW PRESSURE LIFTING NORTHEAST AND STRETCHING FROM
EASTERN IOWA INTO SOUTHWEST LOWER MICHIGAN. GUIDANCE CONTINUES TO
FAVOR THE ATMOSPHERIC RIVER REMAINING IN PLACE ACROSS THE CWFA
THROUGH THE EARLY AFTERNOON HOURS...AS THE FRONTAL BOUNDARY
APPROACHES THE MISSISSIPPI RIVER EARLY THIS AFTN. STRONG LLVL
CONVERGENCE...WILL CONTINUE OUT AHEAD OF THE FRONTAL BOUNDARY AND
ALLOW FOR FURTHER DESTABILIZATION. GIVEN THE PROGGED HELICITY VALUES
MIDDAY THRU THE AFTN...IT IS POSSIBLE THAT A FEW ROTATING UPDRAFTS
COULD EASILY OCCUR AND ALLOW FOR ISOLATED TORNADOES TO FORM. MODEL
HODOGRAPHS ALSO SUPPORT THE DEVELOPMENT OF BOWING
STORMS/MESO-VORTICIES. ONCE THE BOUNDARY PUSHES EAST ACROSS THE
WESTERN CWFA TEMPS WILL BEGIN TO COOL...HOWEVER IT IS LIKELY THIS
WILL NOT OCCUR UNTIL CLOSER TO 00Z FRI.

IN ADDITION TO THE SEVERE WEATHER AND FLOODING CONCERNS THIS
AFTN...ISALLOBARIC PRES FALLS AND PROGGED WIND FIELDS IN THE
LLVLS...IT APPEARS FREQUENT WIND GUSTS TO 38-40KTS WILL OCCUR IN THE
16-00Z TIMEFRAME. GIVEN THIS SCENARIO...HAVE GONE AHEAD AND HOISTED
A WIND ADVISORY.

TONIGHT...SEVERE WX CONCERNS AND HEAVY RAINFALL WILL QUICKLY COME TO
AN END BY 00-06Z TONIGHT AS UNSEASONABLY COOLER AIR ARRIVES. 850MB
THERMAL TROUGH OF -6 TO -10 DEG C IS POISED TO ARRIVE WITH STRONG
ISALLOBARIC PRES RISES. LOW PRES WILL DEEPEN THIS EVENING AS THE
SHORTWAVE LIFTS NORTHEAST ACROSS LAKE MICHIGAN...AND THE 500MB VORT
LIFTS INTO THE UPPER MIDWEST. THE DRY WEDGE WILL PUSH OVERHEAD OF
THE CWFA CLOSER TO 09Z...WHICH WILL BRING A LULL IN THE PRECIP. THEN
WRAP AROUND MOISTURE WILL QUICKLY PIVOT EAST ACROSS IOWA INTO
NORTHERN IL/NORTHWEST IN ARND DAYBREAK FRI.

FRIDAY THROUGH SATURDAY...COOLER AIR CONTINUES TO ADVECT OVERHEAD.
THE CONCERN WILL BE ON THE LAPSE RATES MIDDAY FRI THAT COULD RESULT
IN SOME CONVECTIVE ELEMENTS TO THE NEAR SFC ENVIRONMENT IF THE SFC
CAN WARM CREATING A SIZABLE THERMAL DIFFERENTIAL FROM 850MB TO THE
SFC. HAVE OPTED TO HOLD ONTO MENTION OF RAIN SHOWERS THRU THE DAY
FRI...FEEL THAT THIS WILL END UP BEING DIURNALLY DRIVEN. SFC TEMPS
WILL REMAIN UNSEASONABLY COOL WITH HIGHS IN THE MID/UPR 40S. TROUGH
AXIS ARRIVES OVERHEAD FRI...THEN REMAINS PROGRESSIVE AND PUSHES EAST
FRI NIGHT WITH MID-LVL HEIGHTS BEGINNING TO RISE. ANTI-CYCLONIC FLOW
BUILDS IN FRI NIGHT IN THE LLVLS...AIDING IN FURTHER EROSION OF THE
MOISTURE AND POSSIBLY PARTIAL CLEARING IN THE SKIES. PRIOR TO THE
THINNING CLOUDS...AND DEPARTURE OF THE MOISTURE...A FEW AREAS OF
LIGHT RAIN/SNOW SHOWERS MAY OCCUR FRI EVE. TEMPS WILL RADIATE INTO
THE UPR 20S TO LOW 30S FRI NIGHT. THERMAL TROUGH ALOFT REMAIN THRU
SAT...HOWEVER TEMPS SHUD WARM TO ARND 50 DEG.

BEACHLER

LONG TERM...SUNDAY INTO THURSDAY...OVERALL HAVE DECENT CONFIDENCE IN
THE OVERALL GENERAL PATTERN DURING THIS PERIOD BUT HAVE VERY LITTLE
CONFIDENCE IN THE DETAILS. THE DEEP UPPER TROUGH CURRENTLY AFFECTING
THE AREA WILL BE WELL OFF TO THE NORTHEAST BY SUNDAY MORNING WITH
LOW AMPLITUDE RIDGING CROSSING THE LOCAL AREA. MEANWHILE...A FAIRLY
LOW AMPLITUDE TROUGH WILL BE CROSSING THE HIGH PLAINS. SURFACE HIGH
PRESSURE WILL BE ACROSS THE GREAT LAKES AND SLOWLY SHIFTING
EASTWARD. THE MAIN ISSUE IS THE SPEED WITH WHICH THESE FEATURES
PROGRESS EASTWARD. WARM ADVECTION WILL COMMENCE AHEAD OF THE UPPER
TROUGH WHICH MAY OCCUR AS EARLY AS SUNDAY MORNING WHICH WOULD RESULT
IN PRECIP CHANCES...BUT THIS MAY BE A BIT TOO FAST. WILL KEEP SMALL
POPS FOR NOW BUT SUSPECT THIS WILL NEED ADJUSTMENT. THE BULK OF THE
FORCING WITH THIS WAVE DOES LOOK TO REMAIN TO THE NORTH HOWEVER SO
ANY PRECIP WOULD BE LIGHT IF THIS STAYS ON TRACK. THERE IS BETTER
AGREEMENT IN A SECONDARY WAVE ARRIVING AND DEEPENING THE LARGER
SCALE UPPER TROUGH WHICH THEN DRIVES SURFACE LOW DEVELOPMENT
SOMEWHERE NEAR MISSOURI WHICH THEN LIFTS NORTHEASTWARD. THIS LOOKS
TO OCCUR IN THE TUESDAY-WEDNESDAY TIME FRAME. THE UPPER TROUGH THEN
PASSES USHERING IN ANOTHER PUSH OF COLDER AIR WITH AN ACTIVE
NORTHWEST UPPER FLOW COMMENCING FOR LATE IN THE WEEK. GENERALLY
BELOW NORMAL TEMPERATURES ARE EXPECTED WITH THE POSSIBLE EXCEPTION
BEING AHEAD OF THE LOW MONDAY AND/OR TUESDAY.

MDB

&&

.HYDROLOGY...
555 AM CDT...

SEE THE MESOSCALE DISCUSSION ABOVE FOR THE LATEST THROUGH THIS
MORNING. WHILE RAINFALL IS EXPECTED TO BECOME SOMEWHAT LESS
WIDESPREAD IN THE AFTERNOON AND EVENING...OCCASIONAL HEAVY RATES
WILL STILL BE SEEN...AND THESE ON TOP OF THE ALREADY MORE THAN
SATURATED GROUND COULD LEAD TO IMMEDIATE FLASH FLOODING. THIS WILL
BE ESPECIALLY TRUE IN AND AROUND CHICAGO. ALL AREA RIVERS ARE
LOOKING AT SIGNIFICANT RISES IF THEY HAVE NOT DONE SO ALREADY.
MAJOR FLOODING WILL OCCUR ON ALMOST ALL RIVER BASINS...INCLUDING
RECORD FLOODING FORECAST ON THE DES PLAINES. SOME SHIFTS IN TIME
AND POTENTIALLY IN MAGNITUDE OF CRESTS IS LIKELY AS THIS EVENT
CONTINUES TO UNFOLD. CRESTS ARE LIKELY TO BE DRAWN
OUT...POTENTIALLY 12 TO 24 HOURS OR MORE ON SOME BASINS.

&&

.AVIATION...

//ORD AND MDW CONCERNS...UPDATED 16...

* AREAS OF SHOWERS IN THE AREA THROUGH EARLY EVENING.
* WINDS HAVE SHIFTED TO THE SOUTH AT MDW...GUSTS WILL INCREASE TO
  20-25 KT BY EARLY AFTERNOON. MORE VARIABLE WINDS AT ORD WILL
  BECOME SOUTHERLY AND GUST TO 20-25 KT BY EARLY TO MID AFTERNOON.
* VARIABILITY IN CEILINGS AND VISIBILITIES THROUGH EARLY AFTERNOON.
  OCCASIONAL PERIODS OF IFR POSSIBLE.

PAW

//DISCUSSION...UPDATED 12Z...

SHOWERS AND THUNDERSTORMS WILL CONTINUE TO TRAIN NORTHEASTWARD FROM
MISSOURI ACROSS NORTHERN ILLINOIS THROUGH THE MORNING HOURS. MOISTURE
TRANSPORT CONTINUES TO BE ABSOLUTELY IMPRESSIVE AS A SURFACE LOW
CONTINUES TO CONSOLIDATE ACROSS NORTHERN MISSOURI. A STRONG 60 TO 70
KT LOW LEVEL JET IS CONTINUALLY PUMPING IN MOISTURE. THEREFORE...NOT
MUCH HAS CHANGED IN THE THINKING...AS IT APPEARS THERE WILL BE
LITTLE IMPROVEMENT UNTIL POSSIBLY EARLY THIS AFTERNOON. EXPECT VIS
TO FALL DOWN AROUND 1 TO 2 MILES UNDER THE HEAVIER SHOWERS. CIGS MAY
BRIEFLY IMPROVE AFTER SOME OF THE HEAVIER SHOWERS MOVE THROUGH.
HOWEVER...IT APPEARS THAT IFR OR LIFR TO LOW MVFR CIGS WILL PREVAIL
FOR THE MORNING.

THE SURFACE WARM FRONT IS PROGRESSING NORTHWARD SLOWER THAN
PREVIOUSLY THOUGHT. AS A RESULT...IT APPEARS THAT THE WINDS WILL
REMAIN VARIABLE OR MORE EASTERLY THROUGH MID MORNING UNTIL THE FRONT
PUSHES NORTH OF THE AREA. ONCE THE WARM FRONT MOVES THROUGH...THE WINDS
WILL BECOME EASTERLY. I DID BACK OF ON THE GUSTS SOME AS IT APPEARS
THE LOW CLOUDS MAY LIMIT THE DEPTH OF THE MIXING.

THE SHOWER AND THUNDERSTORM ACTIVITY SHOULD BEGIN TO ABATE ACROSS
THE AREA BY LATE AFTERNOON OR EARLY IN THE EVENING AS A COLD
FRONT PROGRESSES EASTWARD ACROSS THE AREA EARLY THIS EVENING. ONCE
THIS FRONT COMES ACROSS THE AREA THIS SHOULD BRING AN END TO THE
THREAT OF CONVECTIVE ACTIVITY. HOWEVER...EXPECT THE WINDS TO
REMAIN GUSTY UP AROUND 30 KT BEHIND THIS FRONT AND INTO FRIDAY.

KJB

//ORD AND MDW CONFIDENCE...UPDATED 14Z...

* HIGH CONFIDENCE IN PRECIPITATION TREND...MEDIUM CONFIDENCE IN
  DETAILS.
* HIGH CONFIDENCE IN WIND TREND.
* MEDIUM CONFIDENCE IN CEILING/VISIBILITY DETAILS.

PAW

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

FRIDAY NIGHT...BECOMING VFR.

SATURDAY...VFR...LAKE BREEZE DEVELOPING AND REACHING CHI TERMINALS
EARLY-MID AFTERNOON.

SUNDAY...VFR...SLIGHT CHANCE SHRA.

MONDAY...VFR...CHANCE SHOWERS.

TUESDAY AND WEDNESDAY...MVFR LOWERING TO IFR....CHANCE OF SHOWERS.

KJB

&&

.MARINE...
328 AM CDT

IT WILL BE A MESSY DAY ACROSS THE LAKE TODAY...WITH
THUNDERSTORMS...SOME STRONG TO SEVERE...AND STRONG SOUTHERLY WINDS
SOUTH...ESPECIALLY FOR THE NEAR SHORE WATERS. THE CURRENT NEAR SHORE
GALE WARNING LOOKS GOOD. HOWEVER...IT MIGHT BE HARD TO GET TO GALES
UP NEAR THE LAKE COUNTY ILLINOIS NEAR SHORE WATERS. THE STRONGEST
SOUTHERLY WINDS UP TO 40 KT IS EXPECTED ACROSS THE INDIANA NEAR
SHORE WATERS. ALTHOUGH THE WINDS WILL BE SCREAMING ONLY A COUPLE
HUNDRED FEET OFF THE WATER SURFACE...STABLE CONDITIONS OVER THE OPEN
WATERS SHOULD LIMIT THE AMOUNT OF THIS STRONG MOMENTUM ABLE TO MIX
TO THE WATER SURFACE...WITH THE EXCEPTION OF STRONG WINDS WITH ANY
STRONG THUNDERSTORMS.

A SURFACE LOW IS EXPECTED TO STRENGTHEN AND CONSOLIDATE ACROSS THE
WESTERN GREAT LAKES TODAY AND TONIGHT. THE TRACK OF THIS LOW SHOULD
BE SOMEWHERE ACROSS THE NORTHERN HALF OF THE LAKE THIS EVENING.
WHERE THIS LOW TRACKS THE WINDS WILL BE VARIABLE IN DIRECTION FOR A
PERIOD. THIS SYSTEM WILL PUSH A COLD FRONT ACROSS THE LAKE THROUGH
THE NIGHT TONIGHT. STRONG PRESSURE RISES AND COLD AIR ADVECTION
SHOULD RESULT IN THE DEVELOPMENT OF WESTERLY GALES VERY LATE TONIGHT
AND DURING THE DAY ON FRIDAY. IT CURRENTLY APPEARS THAT GALES OF 35
TO 40 KT ARE THE FAVORED WIND SPEEDS. THESE STRONG WINDS WILL ALSO
AFFECT THE NEAR SHORE WATERS AS WELL. I ISSUED A GALE WARNING FOR
THE OPEN WATERS FOR FRIDAY AND FRIDAY EVENING.

WINDS SHOULD ABATE ON SATURDAY AS A SURFACE RIDGE OF HIGH PRESSURE
BUILDS ACROSS THE GREAT LAKES. HOWEVER...THE WEATHER PATTERN LOOKS
TO BECOME ACTIVE AGAIN NEXT WEEK...WITH THE POTENTIAL FOR ANOTHER
SIGNIFICANT SYSTEM TO AFFECT THE GREAT LAKES REGION BY THE MIDDLE OF
NEXT WEEK.

KJB

&&

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLOOD WATCH...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-ILZ011-
     ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021-ILZ022-ILZ023-
     ILZ032-ILZ033-ILZ039 UNTIL 7 AM FRIDAY.

IN...FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-INZ019 UNTIL 7 AM
     FRIDAY.

LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
     LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
     LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...4 AM FRIDAY TO 4 AM
     SATURDAY.

     GALE WATCH...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-LMZ745...4 AM
     FRIDAY TO 10 PM FRIDAY.

&&

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
1141 AM CDT THU APR 18 2013

ILZ003>006-008-010>014-019>023-032-033-039-INZ001-002-010-011-019-
191645-
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-
1141 AM CDT THU APR 18 2013 /1241 PM EDT THU APR 18 2013/

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

.DAY ONE...THIS AFTERNOON AND TONIGHT.

  WEATHER HAZARDS EXPECTED:

  FLOODING.

  THUNDERSTORMS...SOME MAY PRODUCE:
    HEAVY RAIN.
    CLOUD TO GROUND LIGHTNING.

  AREAS AFFECTED AND TIMING:

  ADDITIONAL THUNDERSTORMS ARE POSSIBLE THIS AFTERNOON INTO EARLY
  THIS EVENING...ESPECIALLY ACROSS NORTHWEST INDIANA INTO EAST
  CENTRAL ILLINOIS.

  DISCUSSION:

  MORNING SHOWERS AND THUNDERSTORMS HAVE GREATLY REDUCED THE
  AMOUNT OF AVAILABLE INSTABILITY...LEADING TO A SUBSTANTIALLY
  REDUCED THREAT OF SEVERE WEATHER TODAY AND TONIGHT. ADDITIONAL
  RAINFALL IS EXPECTED THIS AFTERNOON INTO EARLY THIS
  EVENING...WHICH WILL EXASPERATE THE ONGOING FLOODING. SOME
  THREAT FOR EMBEDDED THUNDERSTORMS DOES STILL EXIST...ESPECIALLY
  SOUTHEAST OF INTERSTATE 55 WHICH IS ALSO WHERE THE MOST
  SIGNIFICANT ADDITIONAL RAINFALL WILL BE.

  PORTIONS OF MANY AREA RIVERS AND STREAMS WILL REMAIN NEAR OR
  ABOVE FLOOD STAGE DUE TO RECENT RAINFALL.

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

PORTIONS OF MANY AREA RIVERS AND STREAMS WILL REMAIN NEAR OR
ABOVE FLOOD STAGE FOR MANY DAYS DUE TO RECENT RAINFALL.

.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>745-191645-
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-
1141 AM CDT THU APR 18 2013

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.

THERE IS A CHANCE OF A THUNDERSTORM THIS AFTERNOON.

GALE FORCE WINDS ARE POSSIBLE LATE TONIGHT.

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

GALE FORCE WINDS ARE EXPECTED TO DEVELOP AGAIN FRIDAY MORNING AND
CONTINUE THROUGH FRIDAY NIGHT. HIGH WAVES WILL LIKELY CONTINUE TO
PRODUCE HAZARDOUS CONDITIONS FOR SMALL CRAFT THROUGH FRIDAY NIGHT
PARTICULARLY ALONG THE INDIANA SHORE.

&&

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-
870-872-874-876-878-191645-
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-
1141 AM CDT THU APR 18 2013

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

.DAY ONE...THIS AFTERNOON AND TONIGHT.

THERE IS A CHANCE OF THUNDERSTORMS THROUGH EARLY THIS EVENING.

GALE FORCE WINDS ARE LIKELY FROM LATE TONIGHT.

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

GALE FORCE WINDS ARE EXPECTED THROUGH LATE FRIDAY NIGHT.

&&

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

IZZI

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
1015 AM CDT THU APR 18 2013

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

1009 AM     HEAVY RAIN       2 N STREATOR            41.15N 88.83W
04/18/2013  M3.83 INCH       LA SALLE           IL   TRAINED SPOTTER

&&

ACS

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
1022 AM CDT THU APR 18 2013

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

0920 AM     TSTM WND DMG     MOUNT AYR               40.95N 87.30W
04/18/2013                   NEWTON             IN   TRAINED SPOTTER

            SEVERAL POWER POLES BLOWN DOWN ONTO CR200S BETWEEM
            MERIDAN RD ANDD 100W IN NEWTON COUNTY. WINDS EST AT 60
            MPH.

&&

BN

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
1035 AM CDT THU APR 18 2013

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

0955 AM     FLOOD            WOODRIDGE               41.74N 88.04W
04/18/2013                   DUPAGE             IL   NWS EMPLOYEE

            OBSERVED WATER PARTIALLY COVERING THE ROADWAY AT MULTIPLE
            LOCATIONS ALONG RT. 53 IN BETWEEN 75TH AND ROYCE ROADS.

&&

RODRIGUEZ

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
1038 AM CDT THU APR 18 2013

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

1009 AM     HEAVY RAIN       TONICA                  41.21N 89.07W
04/18/2013  M6.20 INCH       LA SALLE           IL   TRAINED SPOTTER

&&

ACS

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
1040 AM CDT THU APR 18 2013

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

0832 AM     TSTM WND DMG     EARL PARK               40.69N 87.42W
04/18/2013                   BENTON             IN   EMERGENCY MNGR

            PART OF THE ROOF OF A RETIRMENT HOME COLLAPSED.

&&

ALLSOPP

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
1157 AM CDT THU APR 18 2013

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

1156 AM     HEAVY RAIN       3 SW MIDWAY AIRPORT     41.75N 87.79W
04/18/2013  M4.29 INCH       COOK               IL   CO-OP OBSERVER

            STORM TOTAL

&&

ACS