Gale Watch 21, NWS Chicago, IL

121 
WHUS73 KLOT 281526
MWWLOT

URGENT - MARINE WEATHER MESSAGE
NATIONAL WEATHER SERVICE CHICAGO IL
1026 AM CDT WED SEP 28 2011

LMZ740>745-282330-
/O.CON.KLOT.GL.A.0021.110929T2100Z-111001T0300Z/
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-
1026 AM CDT WED SEP 28 2011

...GALE WATCH REMAINS IN EFFECT FROM THURSDAY AFTERNOON THROUGH
FRIDAY EVENING...

A GALE WATCH REMAINS IN EFFECT FROM THURSDAY AFTERNOON THROUGH
FRIDAY EVENING. 

* SUSTAINED GALE FORCE WINDS OR FREQUENT GALE FORCE GUSTS ARE 
  POSSIBLE FROM THURSDAY AFTERNOON THROUGH FRIDAY EVENING.

* DURING THE GALE WATCH...THE STRONGEST WINDS WILL BE UP TO 45 
  KT FROM THE NORTHWEST. THE HIGHEST SIGNIFICANT WAVES WILL BE 
  UP TO 16 FT. THERE WILL BE OCCASIONAL WAVES UP TO 24 FT.

REFER TO THE LATEST MARINE FORECASTS FOR MORE DETAILED
INFORMATION.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A GALE WATCH IS ISSUED WHEN THE RISK OF GALE FORCE WINDS OF 34 TO
47 KNOTS HAS SIGNIFICANTLY INCREASED...BUT THE SPECIFIC TIMING
AND/OR LOCATION IS STILL UNCERTAIN. IT IS INTENDED TO PROVIDE
ADDITIONAL LEAD TIME FOR MARINERS WHO MAY WISH TO CONSIDER
ALTERING THEIR PLANS.

&&

$$

LMZ080-669-671-673-675-777-779-870-872-874-876-878-282330-
/O.CON.KLOT.SR.A.0001.110929T2100Z-110930T1400Z/
LAKE MICHIGAN FROM MICHIGAN CITY IN TO ST. JOSEPH MI 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 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-
1026 AM CDT WED SEP 28 2011

...STORM WATCH REMAINS IN EFFECT FROM THURSDAY AFTERNOON THROUGH
FRIDAY MORNING...

A STORM WATCH REMAINS IN EFFECT FROM THURSDAY AFTERNOON THROUGH
FRIDAY MORNING. 

* SUSTAINED STORM FORCE WINDS OR FREQUENT STORM FORCE GUSTS ARE 
  POSSIBLE FROM THURSDAY AFTERNOON THROUGH FRIDAY MORNING.

* DURING THE STORM WATCH...THE STRONGEST WINDS WILL BE UP TO 50 
  KT FROM THE NORTHWEST. THE HIGHEST SIGNIFICANT WAVES WILL BE 
  UP TO 18 FT. THERE WILL BE OCCASIONAL WAVES UP TO 27 FT.

REFER TO THE LATEST MARINE FORECASTS FOR MORE DETAILED
INFORMATION.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A STORM WATCH IS ISSUED WHEN THE RISK OF STORM FORCE WINDS OF
48 TO 63 KNOTS HAS SIGNIFICANTLY INCREASED...BUT THE SPECIFIC
TIMING AND/OR LOCATION IS STILL UNCERTAIN.  IT IS INTENDED TO
PROVIDE ADDITIONAL LEAD TIME FOR MARINERS WHO MAY WISH TO
CONSIDER ALTERING THEIR PLANS.

&&

$$

LMZ261-362-364-366-563-565-567-868-282330-
/O.CON.KLOT.SR.A.0001.110930T0200Z-110930T1400Z/
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 PENTWATER TO MANISTEE MI 5 NM OFFSHORE TO MID
LAKE-
1026 AM CDT WED SEP 28 2011

...STORM WATCH REMAINS IN EFFECT FROM THURSDAY EVENING THROUGH
FRIDAY MORNING...

A STORM WATCH REMAINS IN EFFECT FROM THURSDAY EVENING THROUGH
FRIDAY MORNING. 

* SUSTAINED STORM FORCE WINDS OR FREQUENT STORM FORCE GUSTS ARE 
  POSSIBLE FROM THURSDAY EVENING THROUGH FRIDAY MORNING.

* DURING THE STORM WATCH...THE STRONGEST WINDS WILL BE UP TO 50 
  KT FROM THE NORTH. THE HIGHEST SIGNIFICANT WAVES WILL BE UP 
  TO 18 FT. THERE WILL BE OCCASIONAL WAVES UP TO 27 FT.

REFER TO THE LATEST MARINE FORECASTS FOR MORE DETAILED
INFORMATION.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A STORM WATCH IS ISSUED WHEN THE RISK OF STORM FORCE WINDS OF
48 TO 63 KNOTS HAS SIGNIFICANTLY INCREASED...BUT THE SPECIFIC
TIMING AND/OR LOCATION IS STILL UNCERTAIN.  IT IS INTENDED TO
PROVIDE ADDITIONAL LEAD TIME FOR MARINERS WHO MAY WISH TO
CONSIDER ALTERING THEIR PLANS.

&&

$$

LENNING

629 
WHUS73 KLOT 282029
MWWLOT

URGENT - MARINE WEATHER MESSAGE
NATIONAL WEATHER SERVICE CHICAGO IL
329 PM CDT WED SEP 28 2011

LMZ740>745-290430-
/O.UPG.KLOT.GL.A.0021.110929T2100Z-111001T0300Z/
/O.NEW.KLOT.GL.W.0073.110929T1800Z-111001T0300Z/
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-
329 PM CDT WED SEP 28 2011

...GALE WARNING IN EFFECT FROM 1 PM THURSDAY TO 10 PM CDT
FRIDAY...

THE NATIONAL WEATHER SERVICE IN CHICAGO HAS ISSUED A GALE
WARNING...WHICH IS IN EFFECT FROM 1 PM THURSDAY TO 10 PM CDT
FRIDAY. 

* EXPECT SUSTAINED GALE FORCE WINDS OR FREQUENT GALE FORCE GUSTS
  FROM 1 PM THURSDAY TO 10 PM CDT FRIDAY.

* DURING THE GALE WARNING...THE STRONGEST WINDS WILL BE UP TO 45 
  KT FROM THE NORTHWEST. THE HIGHEST SIGNIFICANT WAVES WILL BE 
  UP TO 16 FT. THERE WILL BE OCCASIONAL WAVES UP TO 24 FT.

REFER TO THE LATEST MARINE FORECASTS FOR MORE DETAILED
INFORMATION.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A GALE WARNING MEANS WINDS OF 34 TO 47 KNOTS ARE IMMINENT OR
OCCURRING. OPERATING A VESSEL IN GALE CONDITIONS REQUIRES
EXPERIENCE AND PROPERLY EQUIPPED VESSELS. IT IS HIGHLY
RECOMMENDED THAT MARINERS WITHOUT THE PROPER EXPERIENCE SEEK SAFE
HARBOR PRIOR TO THE ONSET OF GALE CONDITIONS.

&&

$$

LMZ080-669-671-673-675-777-779-870-872-874-876-878-290430-
/O.UPG.KLOT.SR.A.0001.110929T2100Z-110930T1400Z/
/O.NEW.KLOT.SR.W.0002.110929T2100Z-110930T1800Z/
LAKE MICHIGAN FROM MICHIGAN CITY IN TO ST. JOSEPH MI 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 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-
329 PM CDT WED SEP 28 2011

...STORM WARNING IN EFFECT FROM 4 PM THURSDAY TO 1 PM CDT
FRIDAY...

THE NATIONAL WEATHER SERVICE IN CHICAGO HAS ISSUED A STORM
WARNING...WHICH IS IN EFFECT FROM 4 PM THURSDAY TO 1 PM CDT
FRIDAY. 

* EXPECT SUSTAINED STORM FORCE WINDS OR FREQUENT STORM FORCE GUSTS
  FROM 4 PM THURSDAY TO 1 PM CDT FRIDAY. THE MOST FAVORABLE PERIOD
  FOR STORM FORCE WINDS WILL BE LATE THURSDAY EVENING INTO FRIDAY
  MORNING. 

* DURING THE STORM WARNING...THE STRONGEST WINDS WILL BE UP TO 
  50 KT FROM THE NORTHWEST. THE HIGHEST SIGNIFICANT WAVES WILL 
  BE UP TO 20 FT. THERE WILL BE OCCASIONAL WAVES UP TO 30 FT.

REFER TO THE LATEST MARINE FORECASTS FOR MORE DETAILED
INFORMATION.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A STORM WARNING MEANS WINDS OF 48 TO 63 KNOTS ARE IMMINENT OR
OCCURRING. RECREATIONAL BOATERS SHOULD REMAIN IN PORT...OR TAKE
SHELTER UNTIL WINDS AND WAVES SUBSIDE. COMMERCIAL VESSELS SHOULD
PREPARE FOR VERY STRONG WINDS AND DANGEROUS SEA CONDITIONS...AND
CONSIDER REMAINING IN PORT OR TAKING SHELTER IN PORT UNTIL WINDS
AND WAVES SUBSIDE.

&&

$$

LMZ261-362-364-366-563-565-567-868-290430-
/O.UPG.KLOT.SR.A.0001.110930T0200Z-110930T1400Z/
/O.NEW.KLOT.SR.W.0002.110929T2100Z-110930T1800Z/
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 PENTWATER TO MANISTEE MI 5 NM OFFSHORE TO MID
LAKE-
329 PM CDT WED SEP 28 2011

...STORM WARNING IN EFFECT FROM 4 PM THURSDAY TO 1 PM CDT
FRIDAY...

THE NATIONAL WEATHER SERVICE IN CHICAGO HAS ISSUED A STORM
WARNING...WHICH IS IN EFFECT FROM 4 PM THURSDAY TO 1 PM CDT
FRIDAY. 

* EXPECT SUSTAINED STORM FORCE WINDS OR FREQUENT STORM FORCE GUSTS
  FROM 4 PM THURSDAY TO 1 PM CDT FRIDAY. THE MOST FAVORABLE
  PERIOD FOR STORM FORCE WINDS WILL BE LATE THURSDAY EVENING INTO
  FRIDAY MORNING.

* DURING THE STORM WARNING...THE STRONGEST WINDS WILL BE UP TO 50 KT
  FROM THE NORTH. THE HIGHEST SIGNIFICANT WAVES WILL BE UP TO 18
  FT. THERE WILL BE OCCASIONAL WAVES UP TO 27 FT.

REFER TO THE LATEST MARINE FORECASTS FOR MORE DETAILED
INFORMATION.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A STORM WARNING MEANS WINDS OF 48 TO 63 KNOTS ARE IMMINENT OR
OCCURRING. RECREATIONAL BOATERS SHOULD REMAIN IN PORT...OR TAKE
SHELTER UNTIL WINDS AND WAVES SUBSIDE. COMMERCIAL VESSELS SHOULD
PREPARE FOR VERY STRONG WINDS AND DANGEROUS SEA CONDITIONS...AND
CONSIDER REMAINING IN PORT OR TAKING SHELTER IN PORT UNTIL WINDS
AND WAVES SUBSIDE.

&&

$$

LENNING

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
312 AM CDT WED SEP 28 2011

.DISCUSSION...
251 AM CDT

SHORT TERM (TODAY THROUGH FRIDAY NIGHT)...

THE LITTLE UPPER LOW THAT COULD WILL FINALLY GET BOOTED OUT OF THE
AREA AFTER SPENDING THE BETTER PART OF A WEEK IN THE AREA...BUT NOT
BEFORE GIVING US ONE MORE DAY OF CLOUDINESS AND OCCASIONAL SHOWERS
AS SPIRAL BANDS WHIRL AROUND THE UPPER LOW TODAY. THE UPPER LOW
HAS ALREADY STARTED TO INCH ITS WAY EASTWARD AND THIS TREND WILL
CONTINUE AS THE ZONAL FLOW TO THE NORTH OF THE UPPER LOW BREAKS
DOWN INTO A MUCH MORE AMPLIFIED PATTERN.

SPEAKING OF WHICH...THE NEXT BIG WEATHER MAKER IS THE SHORTWAVE OVER
SOUTHERN BRITISH COLUMBIA EARLY THIS MORNING. NUMERICAL GUIDANCE IS
IN GOOD AGREEMENT ON TAKING THIS SHORTWAVE EAST ACROSS THE CANADIAN
ROCKIES TODAY...BEFORE IT TURNS MORE SOUTHEASTWARD AND CARVES OUT A
VIGOROUS TROUGH OVER THE GREAT LAKES. A SURFACE LOW AND FRONT WILL
RAPIDLY DEVELOP TONIGHT WITH THE SURFACE LOW PROGGED TO TRACK INTO
THE NORTHERN GREAT LAKES AND QUICKLY DEEPEN THURSDAY INTO THURSDAY
NIGHT WITH THE TRAILING COLD FRONT SWEEPING ACROSS THE CWA THURSDAY
AFTERNOON.

OBVIOUSLY THERE WILL BE NO TIME FOR A RETURN FLOW OF DEEP MOISTURE
IN ADVANCE OF THIS FRONT...HOWEVER VERY STRONG LARGE SCALE ASCENT
WITH THE RAPIDLY DEEPENING TROUGH COULD BE ENOUGH TO COMPENSATE FOR
THE RELATIVE LACK OF MOISTURE AND ALLOW FOR A BAND OF STRONG FORCED
CONVECTION TO DEVELOP AND BUILD SOUTHWARD ALONG THE FRONT THURSDAY.
INSTABILITY SHOULD BE FAIRLY WEAK...HOWEVER THE NEAR 200M 500MB
HEIGHT FALLS SUGGEST THAT THE FORCING MAY BE ENOUGH TO COMPENSATE
FOR MINIMAL INSTABILITY AND SUPPORT ADDING AT LEAST A SLIGHT
CHANCE OF THUNDERSTORMS TO THE GRIDS. BEST CHANCE OF PRECIP AND
THUNDER APPEARS TO BE OVER OUR EASTERN CWA AS I EXPECTED
CONVECTION TO BUILD SOUTHWESTWARD DOWN THE FRONT AS THE FRONT
ITSELF RACES SOUTHEASTWARD ACROSS THE CWA. IT WILL BE A BIT OF A
RACE AS TO HOW FAR THROUGH THE CWA THE FRONT WILL BE BEFORE IT
LIGHTS UP AND FOR THAT REASON KEPT POPS QUITE MODEST.

NEXT BIG STORY WILL TURN TO THE BIG POTENTIAL WITH THIS STORM.
STRONG COLD AIR ADVECTION AND PRESSURE RISES BEHIND THE FRONT WILL
LIKELY KEEP THE BOUNDARY LAYER WELL MIXED THURSDAY NIGHT...ALLOWING
FOR WINDS TO STAY UP AND QUITE GUSTY. BUFKIT SOUNDINGS SUPPORT THE
POTENTIAL FOR WIND GUSTS OVER 40 MPH AT TIMES THURSDAY NIGHT INTO
FRIDAY MORNING AND COULD EVEN END UP NEEDING WIND HEADLINES.

NORTHWEST WINDS WILL THEN VEER TO A MORE NORTHERLY DIRECTION LATER
FRIDAY INTO FRIDAY NIGHT WHICH SHOULD SPREAD THE LAKE EFFECT SHOWERS
WESTWARD INTO OUR NORTHWEST INDIANA COUNTIES. FULL FETCH AND LIKELY
ADDITION OF A LAND BREEZE CONVERGENCE ZONE SUPPORTS DRAMATICALLY
RAISING POPS OVER NORTHWEST INDIANA...AND CANNOT EVEN COMPLETELY
RULE OUT A CLAP OR TWO OF THUNDER GIVEN THE VERY STRONG PUSH OF COLD
AIR OVER THE LAKE.

FARTHER WEST IN OUR CWA...WINDS SHOULD BEGIN TO SUBSIDE AND SKIES
CLEAR LIKELY SETTING THE STAGE FOR THE COLDEST NIGHT SO FAR THIS
SEASON. IF CURRENT MODEL TRENDS HOLD...THEN ITS LIKELY THE MORE
SHELTER VALLEYS AND HOLES WOULD SEE FROST SATURDAY MORNING...BUT
DOES APPEAR AS THOUGH ENOUGH OF A GRADIENT 5-10 MPH SHOULD PREVENT A
WIDESPREAD FROST. ACTUALLY AM ALMOST AS CONCERNED ABOUT PORTIONS OF
OUR WESTERN CWA FLIRTING WITH THE FREEZING MARK.

IZZI

LONG TERM (SATURDAY THROUGH TUESDAY)...

HIGH PRESSURE MOVES IN FROM THE WEST SATURDAY MORNING.
HOWEVER...WITH NORTH WINDS AND A MODERATE TO HIGH TEMPERATURE
DIFFERENCE BETWEEN LAKE MICHIGAN AND 850H...LAKE EFFECT PRECIP WILL
PERSIST THROUGH THE EARLY PART OF SATURDAY OVER NORTHWESTERN
INDIANA.  EXPECTING THE LAKE EFFECT MACHINE TO SHUT OFF BY LATE
SATURDAY MORNING...BUT LAKE EFFECT CLOUD COVER WILL LIKELY LINGER
FOR THE MAJORITY OF SATURDAY.  HIGH PRESSURE REMAINS IN THE REGION
FOR THE REMAINDER OF THE EXTENDED FORECAST...LEADING TO A DRY
FORECAST.  ALSO HAVE A WARMING TREND IN PLACE THROUGH MID NEXT
WEEK...WITH MAX TEMPS ON TUESDAY REACHING INTO THE LOW 70S.
NIGHTTIME LOWS WILL REMAIN CHILLY...WITH MIN TEMPS IN THE UPPER 40S
AND LOW 50S.

JEE

&&

.AVIATION...

//ORD AND MDW CONCERNS...UPDATED 08Z...

* MVFR CIGS THROUGH LATE MORNING/EARLY AFTERNOON...THEN VFR.
* POSSIBLE IFR CIGS EARLY THIS MORNING.
* SHOWERS THROUGH EARLY EVENING. CMS

//DISCUSSION...UPDATED 08Z...

FORECAST GENERALLY ON TRACK WITH VFR CIGS ACROSS NORTHWEST IL.
APPEARS CLOUD COVER WILL BE THICK ENOUGH TO PREVENT ANY WIDESPREAD
FOG FROM FORMING...BUT WILL STILL NEED TO BE MONITORED THROUGH
SUNRISE. IFR CIGS AT ORD/MDW STILL APPEAR TO BE CORRELATED WITH
SHOWER ACTIVITY...WITH MORE PREVAILING IFR AND LIFR CIGS SOUTHEAST
OF MDW INTO NORTHWEST INDIANA BUT WITH ADDITIONAL SHOWERS EXPECTED
IN AND AROUND MDW OPTED TO TEMPO OUT AN IFR CIG FOR FEW HRS. CMS

PREVIOUS 06Z DISCUSSION...

SURFACE AND UPPER LOW NOW CENTERED OVER THE FAR SOUTHEAST CORNER
OF LAKE MICHIGAN. BOTH ARE EXPECTED TO SLOWLY MOVE EAST/SOUTHEAST
ACROSS NORTHERN INDIANA LATER TODAY INTO TONIGHT. THUS BANDS OF
SHOWERS WILL CONTINUE TO ROTATE ACROSS NORTHEAST IL AND NORTHWEST
INDIANA INTO THIS EVENING...WITH A GRADUAL DECREASE IN COVERAGE
EXPECTED BY THIS EVENING. WHILE COVERAGE IS EXPECTED TO BE LESS
THAN RECENT DAYS...OPTED TO CONTINUE PREVAILING SHOWERS INTO THE
LATE MORNING HRS WITH VICINITY MENTION INTO THIS EVENING. SHOWER
ACTIVITY AT RFD LIKELY TO END BY MID/LATE MORNING. COULD ALSO BE A
RUMBLE OF THUNDER WITH ANY MORE CONVECTIVE SHOWERS...BUT ISOLATED
COVERAGE AT BEST PRECLUDES MENTION IN THE FORECAST.

WITH THE LOW EAST OF THE TERMINALS...CONFIDENCE INCREASING THAT
PREVAILING IFR CIGS ARE NOT LIKELY. COULD STILL BE PATCHY IFR WITH
SOME OF THE HEAVIER SHOWERS AND THUS CARRIED SCATTERED MENTION
WITH THIS FORECAST...BUT EXPECT PREVAILING CIGS TO REMAIN MVFR...
OR BETTER...WITH MVFR CIGS LIFTING TO VFR BY AFTERNOON...EARLIER
AT RFD. CIGS SHOULD THEN SCATTER OUT THIS EVENING.

WITH MORE CLOUD COVER SPREADING SOUTH/SOUTHWEST ACROSS THE CWA
EARLY THIS MORNING...THINK THAT WILL MINIMIZE FOG POTENTIAL. BUT
BREAKS OVER THE PAST FEW HRS HAD ALLOWED SOME LOCATIONS TO DIP
INTO THE 2-4SM RANGE. SHOULD ADDITIONAL BREAKS FORM...MOST LIKELY
NEAR RFD/DPA...MAY NEED TO INCLUDE LOWER VIS FOR FOG POTENTIAL AND
WILL MONITOR TRENDS THROUGH THE NIGHT. WITH WINDS DIMINISHING THIS
EVENING INTO THE OVERNIGHT HRS AND CLEARING SKIES...COULD BE FOG
AGAIN LATE TONIGHT INTO THURSDAY MORNING. CMS

//ORD AND MDW CONFIDENCE...UPDATED 08Z...

* MEDIUM CONFIDENCE PREVAILING CIGS WILL REMAIN MVFR THROUGH MID/
  LATE MORNING.
* MEDIUM CONFIDENCE CIGS WILL LIFT TO VFR THIS AFTERNOON.
* MEDIUM CONFIDENCE SHOWERS WILL CONTINUE THROUGH EARLY EVENING...
  LOW CONFIDENCE ON TIMING/COVERAGE. CMS

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

THURSDAY...WINDY AFTERNOON/EVENING. CHANCE OF SHRA.
FRIDAY...BREEZY. CHANCE OF SHRA.
SATURDAY THROUGH MONDAY...VFR.

KJB

&&

.MARINE...
311 AM CDT

PERSISTENT AREA OF LOW PRESSURE CONTINUES TO REMAIN ACROSS THE
REGION...SLOWLY MAKING AN EASTWARD PROGRESSION ACROSS THE FAR
SOUTHERN PORTIONS OF THE LAKE THIS MORNING. THIS IS ONGOING AS
PRESSURE FIELD ACROSS THE NORTHERN HALF OF THE LAKE IS RATHER
RELAXED AS WEAK HIGH PRESSURE IS CURRENTLY OVERHEAD. WITH TIME
TODAY...THIS AREA OF LOW PRESSURE WILL CONTINUE TO THE EAST AS IT
WEAKENS WITH THE PRESSURE FIELD AND FLOW OVER THE ENTIRE LAKE
BECOMING RELAXED AND COMING DOWN. EXPECT THESE CONDITIONS TO
CONTINUE TONIGHT...BUT AS ANOTHER TROUGH OF LOW PRESSURE DEVELOPS
TO THE NORTH OVER ONTARIO.

THIS TROUGH OF LOW PRESSURE WILL STRENGTHEN AS IT MOVES CLOSER TO
NORTHERN LAKE MICHIGAN BY THURSDAY MORNING...AND WILL BE
RESPONSIBLE FOR SOME STRONG WINDS OVER THE ENTIRE LAKE THURSDAY
AFTERNOON INTO FRIDAY NIGHT. GALES WILL DEFINITELY BE POSSIBLE
WITH THIS SYSTEM WITH EVEN STORM FORCE WINDS POSSIBLE BY LATE IN
THE DAY ON THURSDAY THROUGH FRIDAY MORNING. THIS WILL BE DUE IN
PART TO PRESSURE GRADIENT/FLOW STRENGTHENING AND INCREASING...WITH
A STRONG PUSH OF MUCH COLDER AIR ALSO EXPECTED. WINDS WILL BE
DIMINISHING BY FRIDAY MORNING...BUT WITH GALE FORCE WINDS TO
CONTINUE FOR MUCH OF THE DAY FRIDAY. IT ISNT UNTIL FRIDAY EVENING
WHEN WINDS REALLY BEGIN TO COME DOWN WITH HIGH PRESSURE TRYING TO
SHIFT EAST ACROSS THE REGION. ALTHOUGH IT WILL BE SLOW TO SHIFT
ACROSS THE LAKE INTO THE START OF THE WEEKEND. SO DESPITE
DIMINISHING WINDS...DO EXPECT STRONGER NORTHERLY WINDS TO PERSIST
BEFORE THIS HIGH FINALLY SHIFTS OVERHEAD LATE IN THE DAY ON
SATURDAY.

RODRIGUEZ

&&

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...STORM WATCH...LMZ080-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-
     LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...4 PM THURSDAY TO 9 AM
     FRIDAY.

     STORM WATCH...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-LMZ567-
     LMZ868...9 PM THURSDAY TO 9 AM FRIDAY.

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

&&

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
350 PM CDT TUE SEP 27 2011

ILZ003>006-008-010>014-019>023-032-033-039-INZ001-002-010-011-019-
282100-
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-
350 PM CDT TUE SEP 27 2011 /450 PM EDT TUE SEP 27 2011/

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

.DAY ONE...TONIGHT.

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY.

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.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>745-282100-
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-
350 PM CDT TUE SEP 27 2011

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

.DAY ONE...TONIGHT.

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY.

STRONG WINDS AND HIGH WAVES WILL LEAD TO HAZARDOUS CONDITIONS FOR
SMALL CRAFT FOR THE ILLINOIS AND INDIANA NEARSHORE WATERS
THURSDAY NIGHT INTO FRIDAY...WITH GALES LIKELY OVER THE INDIANA
NEARSHORE.

&&

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-
870-872-874-876-878-282100-
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-
350 PM CDT TUE SEP 27 2011

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

.DAY ONE...TONIGHT.

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY.

GALE FORCE WINDS ARE LIKELY LATE THURSDAY THROUGH FRIDAY.

&&

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

RC

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
953 PM CDT TUE SEP 27 2011

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

0953 PM     HEAVY RAIN       POLO                    41.98N 89.58W
09/27/2011  M2.20 INCH       OGLE               IL   CO-OP OBSERVER

            3 DAY STORM TOTAL.

&&

KBIRK

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
1058 PM CDT TUE SEP 27 2011

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

1056 PM     HEAVY RAIN       CHESTERTON              41.60N 87.06W
09/27/2011  M1.20 INCH       PORTER             IN   TRAINED SPOTTER

            24-HOUR TOTAL

&&

JEE