Flash Flood Warning 1, NWS St. Louis, MO

000 
WGUS73 KLSX 110740
FFSLSX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
140 AM CST WED FEB 11 2009

MOC051-110750-
/O.CAN.KLSX.FF.W.0001.000000T0000Z-090211T1045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
COLE MO-
140 AM CST WED FEB 11 2009

...THE FLASH FLOOD WARNING HAS BEEN CANCELLED FOR COLE COUNTY...

THE STORMS WHICH PRODUCED THE HEAVY RAINS EARLIER HAVE WEAKENED AND 
MOVED OUT OF THE WARNED AREA. ADDITIONALLY...AREA LAW ENFORCEMENT 
INDICATES THAT FLOODING IS NO LONGER A PROBLEM IN THE AREA.

LAT...LON 3874 9239 3872 9235 3867 9235 3864 9223
      3860 9220 3857 9213 3856 9203 3860 9195
      3855 9203 3850 9201 3847 9204 3846 9210
      3847 9217 3839 9212 3838 9218 3833 9220
      3834 9241 3842 9240 3843 9249

$$

CARNEY

AREA FORECAST DISCUSSION...UPDATED AVIATION
NATIONAL WEATHER SERVICE ST LOUIS MO
607 PM CST TUE FEB 10 2009

.DISCUSSION...
/249 PM CST TUE FEB 10 2009/

VERY BUSY WEATHER PATTERN EXPECTED OVER THE NEXT 24-30 HOURS...
1. FLASH FLOOD WATCH STILL LOOKS ON TARGET...ESPECIALLY IN LIGHT
OF NEW EXCESSIVE RAINFALL OUTLOOK WHICH PLACES A LARGE PART OF THE
CWA IN A MODERATE RISK TO REACH FFG. IN ADDITION TO THE FLASH
FLOOD POTENTIAL...AREA RIVERS WILL LIKELY RISE AND A HYDROLOGIC
OUTLOOK (ESFLSX) WILL BE ISSUED TO ADDRESS THIS. FURTHER
INFORMATION CAN BE FOUND BELOW IN THE HYDROLOGY SECTION OF THIS
AFD. 2. WILL ALSO BE ISSUING A WIND ADVISORY FOR LATE TONIGHT AND
TOMORROW FOR THE ERN AND SRN PARTS OF THE CWA. 3. MOST OF THE CWA
REMAINS IN A SLIGHT RISK WITH ENHANCED PROBABILITIES FOR WIND
(30%) OVER THE SRN PART OF THE CWA LATE TONIGHT AND THE SERN
COUNTIES TOMORROW MORNING. MOST LIKELY TIME TO SVR WILL BE BETWEEN
3 AM AND 9 AM.

MODELS ARE IN GOOD AGREEMENT THAT MID LEVEL TROUGH CURRENTLY OVER
THE SOUTHWEST WILL DEEPEN AS IT MOVES QUICKLY TO THE NORTHEAST AND
ACROSS MO/IL TOMORROW. DYNAMICS ARE VERY IMPRESSIVE WITH COUPLED
JET/STRONG MID LEVEL ASCENT/STRONG 925-850MB MOISTURE CONVERGENCE
ON NOSE OF 70KT LOW LEVEL JET. PWATS WILL BE CLOSE TO 1.3 WHICH
IS WELL ABOVE FEBRUARY NORMALS. EXPECT WARM AIR ADVECTION
SHRA/TSRA TO DEVELOP BY LATE EVENING OVER THE AREA. HOW THESE WILL
AFFECT THE SVR POTENTIAL ASSOCIATED WITH A SQUALL LINE THAT WILL
MOVE ACROSS THE SRN HALF OF THE CWA 09-15Z IS UNCERTAIN. NAM/SREF
IS DEPICTING MUCAPES 500-1000 J/KG WHICH IS MORE THAN SUFFICIENT
GIVEN THE 0-6KM SHEAR OF 80KT/0-1KM SHEAR OF 40KTS/0-1KM SRH AOA
300. PRIMARY CONCERN IS DAMAGING WINDS...BUT THIS ENVIRONMENT IS
CONDUCIVE TO ISOLATED COOL SEASON TORNADOES. SEVERE THREAT SHOULD
END BY LATE MORNING ONCE THE FRONT MOVES THROUGH.

THE WIND ADVISORY WILL COVER EXPECTED INCREASE IN WIND SPEED LATE
TONIGHT IN THE TIGHT PRESSURE GRADIENT AHEAD OF THE WARM SECTOR AND
ALSO IN THE DRY SLOT TO THE SOUTH OF THE LOW TRACK TOMORROW WHERE
MIXING COULD BRING DOWN SOME MOMENTUM FROM THE 50KT 850MB WINDS.
HAVE NOT INCLUDED THE REST OF THE CWA AT THIS TIME...BUT THE NRN AND
WRN COUNTIES WILL BE GETTING CLOSE TO CRITERIA TOMORROW AFTERNOON
ONCE THE LOW LIFTS OUT.

FLASH FLOOD REMAINS A THREAT GIVEN THE REASON MENTIONED ABOVE.  HAVE
WIDESPREAD 1-3 QPF TOTALS GOING THROUGH 00Z TOMORROW...WITH THE
HIGHEST TOTALS THROUGH THE CENTRAL CWA WHERE THE LOW WILL TRACK.
TSRA COULD LOCALLY ENHANCE THESE TOTALS. THESE AMOUNTS EXCEED
GOING 3 AND 6 HOUR FLASH FLOOD GUIDANCE. HAVE GONE WITH ALL RAIN
WITH THIS EVENT...BUT FORECAST SOUNDINGS ARE DROPPING QUICKLY
RIGHT ABOUT THE TIME THAT THE PRECIPITATION IS GETTING READY TO
END. THERE IS A SMALL CHANCE THAT STRONG UVV COULD COOL THE
COLUMN MORE THAN IS FORECAST...WHICH COULD CAUSE THE
PRECIPITATION TO END AS SNOW OVER PARTS OF NERN MO/W CNTRL IL. DRY
WEATHER THEN SETS IN FROM TOMORROW NIGHT INTO EARLY FRIDAY.

TEMPERATURES ARE A COMBINATION OF THE NAM/SREF 2M TEMPERATURES.

FOR FRIDAY NIGHT INTO NEXT TUESDAY...MEDIUM RANGE MODELS ALL AGREE
WITH A PROGRESSIVE PATTERN OVER THE CENTRAL CONUS.  THERE IS ALSO
DECENT AGREEMENT BETWEEN THE GEM/ECWMF AND THE NEW 12Z GFS THAT A
SHORTWAVE TROUGH WILL MOVE ACROSS MO/IL ON FRIDAY NIGHT WITH >0.25
QPF NORTH OF I-70.  HAVE KEPT WITH THE IDEA OF A RAIN/SNOW MIX ALONG
I-70 WITH JUST SNOW OVER THE NRN THIRD OF THE CWA SO WILL NEED TO
MONITOR FOR POTENTIAL ACCUMULATIONS.  SYSTEM MOVES QUICKLY EWD AND
THERE IS SOME SMALL POSSIBLITY OF PRECIPITATION OVER THE
WEEKEND...BUT WILL KEEP THE CHANCES SLIGHT BECAUSE OF DIFFERENCES IN
MODEL TIMING IN THE FAST FLOW.  BOTH GFS/ECWMF ARE IN DECENT
AGREEMENT WITH A SIGNIFICANT SHORTWAVE MOVING INTO THE REGION EARLY
NEXT WEEK...SO HAVE ADDED A CHANCE OF RAIN NEXT TUESDAY.

BRITT

&&

.AVIATION...
/550 PM CST TUE FEB 10 2009/
FOR THE 00Z TAFS...
SHOWERS AND THUNDERSTORMS WILL OVERSPREAD THE AREA THIS
EVENING. PRIMARY CONCERN WILL BE MVFR/IFR CONDITIONS IN THE
STRONGEST STORMS. THINK THE GREATEST THREAT FOR STORMS WILL BE
BETWEEN 04Z AND 09Z ACROSS THE AREA...BUT HEAVY RAIN WILL CONTINUE
TO BE A POSSIBLITY THROUGHOUT THE NIGHT. ANOTHER ROUND OF THUNDER
LOOKS LIKELY BETWEEN 12Z AND 16Z WEDNESDAY AS THE UPPER LEVEL
STORM SYSTEM MOVES OVERHEAD GREATLY INCREASING THE INSTABILITY. LOW
CIGS/VSBYS WILL CONTINUE AT LEAST THROUGH EARLY WEDNESDAY
AFTERNOON WITH SOME CLEARING TOWARD WEDNESDAY EVENING.

CARNEY

&&

.HYDROLOGY...
BASED ON THIS MORNINGS 24-HOUR RAINFALL FORECAST FROM THE
HYDROMETEOROLOGICAL PREDICTION CENTER...THE GREATEST POTENTIAL FOR
RIVER FLOODING WOULD BE IN THE FOLLOWING RIVER BASINS:  THE MERAMEC
RIVER INCLUDING THE BOURBEUSE AND BIG RIVER BASINS...THE BLACK
RIVER...THE CUIVRE RIVER...THE KASKASKIA RIVER...AND THE ILLINOIS
RIVER BASINS.

SOME OF THE RAINFALL IN THIS EVENT WILL FALL AFTER THE INITIAL
24-HOUR RAINFALL FORECAST.  TO ACCOUNT FOR THE ENTIRE STORM
RAINFALL...THE RIVER FOREDAST CENTERS RUN CONTINGENCY FORECASTS TO
ESTIMATE FLOOD POTENTIAL FOR THE ENTIRE STORM...WHICH SHOULD END BY
ABOUT MIDDAY WEDNESDAY.

CONTINGENCY FORECASTS FROM THE RIVER FORECAST CENTERS USING 48 HOURS
OF FORECAST RAINFALL INDICATE SIGNIFICANT FLOODING IS POSSIBLE ALONG
THE MERAMEC RIVER...ON THE KASKASKIA RIVER NEAR VANDALIA...AND ALONG
THE ILLINOIS RIVER...THOUGH THE HIGHER LEVELS ON THAT RIVER WOULD
NOT BE REALIZED UNTIL NEXT WEEK.

FUCHS

&&

.LSX WATCHES/WARNINGS/ADVISORIES...
MO...FLASH FLOOD WATCH FROM MIDNIGHT CST TONIGHT THROUGH WEDNESDAY
     MORNING FOR AUDRAIN-BOONE-CALLAWAY-COLE-CRAWFORD-FRANKLIN-
     GASCONADE-IRON-JEFFERSON-LINCOLN-MADISON-MONITEAU-MONROE-
     MONTGOMERY-OSAGE-PIKE-RALLS-REYNOLDS-ST. CHARLES-ST.
     FRANCOIS-ST. LOUIS-ST. LOUIS CITY-STE. GENEVIEVE-WARREN-
     WASHINGTON.

     WIND ADVISORY FROM 3 AM TO 6 PM CST WEDNESDAY FOR CRAWFORD-IRON-
     JEFFERSON-MADISON-REYNOLDS-ST. FRANCOIS-STE. GENEVIEVE-
     WASHINGTON.

IL...FLASH FLOOD WATCH FROM MIDNIGHT CST TONIGHT THROUGH WEDNESDAY
     MORNING FOR BOND IL-BROWN IL-CALHOUN IL-CLINTON IL-FAYETTE
     IL-GREENE IL-JERSEY IL-MACOUPIN IL-MADISON IL-MARION IL-
     MONROE IL-MONTGOMERY IL-PIKE IL-RANDOLPH IL-ST. CLAIR IL-
     WASHINGTON IL.

     WIND ADVISORY FROM 3 AM TO 6 PM CST WEDNESDAY FOR BOND IL-
     CLINTON IL-FAYETTE IL-MACOUPIN IL-MADISON IL-MARION IL-
     MONROE IL-MONTGOMERY IL-RANDOLPH IL-ST. CLAIR IL-WASHINGTON
     IL.

&&

WFO LSX

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE ST LOUIS MO
402 PM CST TUE FEB 10 2009

ILZ058>060-064-065-069-070-074-079-095>102-MOZ018-019-026-027-
034>036-041-042-047>052-059>065-072>075-084-085-099-111130-
GREENE IL-MACOUPIN IL-MONTGOMERY IL-BOND IL-FAYETTE IL-CLINTON IL-
MARION IL-WASHINGTON IL-RANDOLPH IL-ADAMS IL-BROWN IL-PIKE IL-
CALHOUN IL-JERSEY IL-MADISON IL-ST. CLAIR IL-MONROE IL-KNOX-LEWIS-
SHELBY-MARION-MONROE-RALLS-PIKE-BOONE-AUDRAIN-MONITEAU-COLE-OSAGE-
CALLAWAY-MONTGOMERY-LINCOLN-GASCONADE-WARREN-ST. CHARLES-FRANKLIN-
ST. LOUIS-ST. LOUIS CITY-JEFFERSON-CRAWFORD-WASHINGTON-
ST. FRANCOIS-STE. GENEVIEVE-IRON-MADISON-REYNOLDS-
402 PM CST TUE FEB 10 2009

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF EASTERN AND
CENTRAL MISSOURI AS WELL AS WEST CENTRAL AND SOUTHWEST ILLINOIS.

.DAY ONE...TONIGHT

HEAVY RAIN IS EXPECTED LATE TONIGHT AS A LOW PRESSURE SYSTEM
APPROACHES THE AREA. A FLASH FLOOD WATCH IS IN EFFECT FOR MOST OF
THE AREA LATE TONIGHT FOR 1 TO 3 INCHES OF RAIN FALLING ON GROUND
THAT IS SATURATED.

THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER THE AREA LATE
TONIGHT...ESPECIALLY OVER SOUTHEAST MISSOURI. THE GREATEST THREAT
WILL BE DAMAGING WINDS...HOWEVER TORNADOES ARE ALSO POSSIBLE
BECAUSE OF THE STRONG WIND SHEAR.

OUTSIDE OF THUNDERSTORMS...SOUTH WINDS ARE EXPECTED TO INCREASE
LATE TONIGHT INTO THE 15 TO 25 MPH RANGE WITH SOME WIND GUSTS IN
EXCESS OF 35 MPH OVER PARTS OF SOUTH CENTRAL AND SOUTHWEST
ILLINOIS AS WELL AS SOUTHEAST MISSOURI.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

HEAVY RAIN IS EXPECTED TO CONTINUE WEDNESDAY MORNING. A FLASH
FLOOD WATCH WILL CONTINUE UNTIL NOON ON WEDNESDAY OVER MOST OF THE
AREA.

THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF
SOUTHEAST AND FAR EAST CENTRAL MISSOURI AS WELL AS SOUTHWEST AND
SOUTH CENTRAL ILLINOIS ON WEDNESDAY MORNING.

WINDY CONDITIONS ARE ALSO EXPECTED ON WEDNESDAY...WITH OCCASIONAL
GUSTS IN THE 40 TO 45 MPH RANGE. A WIND ADVISORY IS IN EFFECT FOR
PARTS OF SOUTH CENTRAL AND SOUTHWEST ILLINOIS AS WELL AS SOUTHEAST
MISSOURI.

THERE IS A CHANCE OF SNOW FRIDAY AND FRIDAY NIGHT...MAINLY ALONG
AND NORTH OF INTERSTATE 70. THERE IS SOME POTENTIAL FOR
ACCUMULATING SNOW OVER NORTHEAST MISSOURI AND WEST CENTRAL
ILLINOIS WITH THIS SYSTEM.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS LIKELY TONIGHT FOR SEVERE WEATHER AND
FLOODING. IN ADDITION TO SEVERE WEATHER...SPOTTERS ARE ASKED TO
REPORT HEAVY RAINFALL AMOUNTS AND ANY FLOODING.

&&

FOR A GRAPHICAL VERSION OF THIS INFORMATION SEE OUR
WEBPAGE AT (LOWERCASE)... HTTP://WWW.WEATHER.GOV/LSX/?N=HWO1

BRITT