River Flood Warning 62, NWS St. Louis, MO

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE ST LOUIS MO
856 PM CST FRI MAR 12 2010

.UPDATE...
/856 PM CST FRI MAR 12 2010/

QUICK UPDATE TO GOING FORECAST TO ADJUST POPS BASED ON CURRENT
RADAR TRENDS AND MOST RECENT RUC OUTPUT. HIGHEST POPS/QPF STILL
LOOKS GOOD OVER THE NRN CWA WHERE AREA OF MODERATE RAIN IS MOVING
WWD NORTH OF THE UPPER LOW. HAVE ALSO INCLUDED A BIT HIGHER POPS
ALONG AND WEST OF MS RIVER INTO THE SRN CWA THE REST OF THE
EVENING WHERE THERE IS A SMALL PATCH OF LIGHT RAIN...BUT GENERAL
TREND WILL BE FOR RAIN TO DIMINISH IN THE ERN AND SRN PARTS OF THE
CWA LATE THIS EVENING AND OVERNIGHT. LATEST RUC SOUNDINGS STILL
SUPPORT ALL LIQUID AND HAVE REFRAINED FROM ADDING ANY MENTION OF
FROZEN PRECIPITATION THE REST OF THE NIGHT. REST OF THE FORECAST
LOOKS GOOD AND HAVE MADE ONLY MINOR ADJUSTMENTS.

BRITT

&&

.DISCUSSION...
/257 PM CST FRI MAR 12 2010/

MAIN FORECAST FOCUS REMAINS PRECIP CHANCES THRU THE WEEKEND.

NOT MUCH HAS CHANGED FROM THE PREV FORECAST FOR THE SHORT TERM.
FORECAST SOUNDINGS SUGGEST A CHANCE OF SN POSSIBLE AROUND 12Z SAT
ACROSS PORTIONS OF CNTL MO. HAVE NOT MENTIONED IN THE FORECAST
ATTM AS BELIEVE THE MODELS ARE TOO COOL IN THE BNDY LAYER. AS
CYCLOGENESIS CONTINUES TONIGHT...EXPECT WAA TO OCCUR ACROSS MUCH
OF THE CWA...ESPECIALLY CNTL AND NE MO AND WCNTL IL.

UPA LOW STILL EXPECTED TO MEANDER AROUND THE MID US BEFORE
FINALLY THE LOW MOVES EWD ON SUN. CYCLONIC FLOW WILL PERSIST OVER
THE REGION THRU THE WEEKEND LEAVING A POSSIBILITY OF SCT LIGHT RA
AND CLOUDS INTO NEXT WEEK.

HAVE KEPT THE FORECAST DRY FOR SUNDAY NIGHT THRU THE END OF NEXT
WEEK. MODELS INDICATE THERE IS A POSSIBILITY OF RA OFF AND ON NEXT
WEEK. HOWEVER...MODEL SOLNS ARE DIFFERENT ENUF WITH LITTLE RUN TO
RUN CONTINUITY THAT MENTION IS NOT NEEDED ATTM.

AS FOR TEMPS...TRENDED TWD THE WARMER MOS TONIGHT DUE TO WAA
MENTIONED ABOVE. FOR TOMORROW...WENT WITH A PERSISTENCE FORECAST
FROM TODAY...JUST A DEGREE OR SO WARMER...ALSO DUE TO THE WAA OVER
THE AREA.

HAVE TEMPS SLOWLY WARMING FOR THE REMAINDER OF THE FORECAST AS
CLOUDS SHUD START TO BREAK UP ALLOWING MORE SOLAR INSOLATION. HAVE
TRENDED TWD THE WARMER MOS FOR MUCH OF NEXT WEEK.

TILLY

&&

.AVIATION...
/535 PM CST FRI MAR 12 2010/

TWO AREAS OF LOW PRESSURE OVER THE MID MISSISSIPPI VALLEY REGION
WILL CONTINUE MERGING TONIGHT BEFORE THE ENTIRE SYSTEM MOVES OFF
TO THE EAST TOMORROW. CIGS MAY VARY BETWEEN VFR AND MVFR FOR THE
NEXT FEW HOURS BEFORE A COMBINATION OF ADVECTION AND LOWERING
CLOUD BASES BRINGS CIGS SOLIDLY INTO MVFR RANGE AND EVENTUALLY
INTO IFR. IFR CIGS SHOULD PERSIST THROUGH EARLY AFTN BEFORE
IMPROVING AS THE SYSTEM PULLS AWAY. INITIALLY NWLY WINDS WILL BACK
WLY OVERNIGHT THEN VEER NWLY BEHIND THE DEPARTING SYSTEM.

SPECIFICS FOR KSTL...-DZ IS EXPECTED TOMORROW AFTN AS THE LOW
PRESSURE SYSTEM MOVES OFF TO THE EAST. OTHERWISE...PLEASE SEE
ABOVE DISCUSSION.

KANOFSKY

&&

.LSX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
IL...NONE.
&&

WFO LSX

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE ST LOUIS MO
334 PM CST FRI MAR 12 2010

ILZ058>060-064-065-069-070-074-079-095>102-MOZ018-019-026-027-
034>036-041-042-047>052-059>065-072>075-084-085-099-131200-
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 MO-
LEWIS MO-SHELBY MO-MARION MO-MONROE MO-RALLS MO-PIKE MO-BOONE MO-
AUDRAIN MO-MONITEAU MO-COLE MO-OSAGE MO-CALLAWAY MO-MONTGOMERY MO-
LINCOLN MO-GASCONADE MO-WARREN MO-ST. CHARLES MO-FRANKLIN MO-
ST. LOUIS MO-ST. LOUIS CITY MO-JEFFERSON MO-CRAWFORD MO-
WASHINGTON MO-ST. FRANCOIS MO-STE. GENEVIEVE MO-IRON MO-
MADISON MO-REYNOLDS MO-
334 PM CST FRI MAR 12 2010

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

.DAY ONE...TONIGHT

WIDESPREAD RAIN WILL CONTINUE TONIGHT AND CONTINUE INTO SATURDAY.
SOME LOCATIONS COULD RECEIVE OVER AN INCH OF RAINFALL DURING THIS
PERIOD...WHICH MAY CONTRIBUTE TO LOCALIZED FLOODING OF SOME
CREEKS...STREAMS AND RIVERS.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

MODERATE RIVER FLOODING IS FORECAST TO BEGIN SUNDAY NIGHT FOR PORTIONS
OF THE MISSISSIPPI RIVER. SEE THE APPROPRIATE FLOOD STATEMENT FOR
SPECIFIC DETAILS.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT ANTICIPATED TONIGHT.

&&

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

TILLY