Severe Thunderstorm Warning 22, NWS St. Louis, MO

000 
WWUS53 KLSX 221121
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
620 AM CDT THU MAR 22 2007

ILC133-163-221130-
/O.CAN.KLSX.SV.W.0022.000000T0000Z-070322T1145Z/
MONROE IL-ST. CLAIR IL-
620 AM CDT THU MAR 22 2007

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHERN ST. CLAIR AND CENTRAL
MONROE COUNTIES IS CANCELLED...

THE STORM WHICH PROMPTED THE WARNING HAS WEAKENED AND NO LONGER 
APPEARED TO BE SEVERE. THE STORM WILL CONTINUE MOVING EAST AT AROUND 
35 MPH AND WILL AFFECT SOUTHERN PORTIONS OF  ST. CLAIR COUNTY 
THROUGH 700 AM. GUSTY WINDS TO AROUND 35 MPH AND SMALL HAIL WILL 
CONTINUE TO BE POSSIBLE AS THE STORM MOVES ACROSS THE AREA.

LAT...LON 3836 9036 3825 9037 3817 9030 3823 8973
      3844 8971

$$

CARNEY

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ST LOUIS MO
437 AM CDT THU MAR 22 2007

.DISCUSSION...
THE 00Z SHORT-TERM MODELS (TIL SUNDAY)...REMAIN IN DECENT
AGREEMENT ON MASS FIELDS AND GENERAL EVOLUTION OF FEATURES THRU
THIS WEEKEND. IN THE WAKE OF STRONG NRN STREAM SHORTWAVE...H500
FLOW BECOMES ZONAL TODAY THRU THE MID MS VALLEY TIL AT LEAST
FRIDAY WHICH WILL EFFECTIVELY FREEZE ANY FEATURES AT THE SURFACE.
THE NAM PROLONGS THE ZONAL FLOW A BIT LONGER THAN THE GFS...BUT
THE SIMILARITIES ARE ALSO THERE...WITH BOTH SHOWING A HINT OF
WSWLY MID LEVEL FLOW RESUMING BY SATURDAY AND A MORE DEFINITIVE
CLUE BY SUNDAY. MAIN H500 LO OVER OFF BAJA CA WILL EVENTUALLY
RESPOND TO /KICKER/ SYS CRASHING INTO THE PAC NW BY SATURDAY...
EJECTING INTO THE CNTRL HI PLAINS BY SUNDAY AND AFFECTING OUR FA
BY LATE MONDAY. UNTIL THEN...SERIES OF WEAK UPPER LEVEL
DISTURBANCES WILL BE KICKED OUT BY THIS SYSTEM AS THEY INTERACT
WITH VERY MOIST AND MODERATELY UNSTABLE ATMOSPHERE...IT WON/T TAKE
MUCH TO GET PCPN GOING FOR THE NEXT FEW DAYS. AT THE SURFACE...
CDFNT EXPECTED TO DROP DOWN TO THE I-70 CORRIDOR TODAY AND THEN
STALL THERE TONIGHT BEFORE EDGING NWD INTO THE NRN FA BY FRIDAY.
THIS FRONTAL BOUNDARY IS THEN EXPECTED TO SLOWLY MEANDER N OF THE
FA BY SATURDAY...PLACING THE FA IN A WARM SECTOR SETUP UNTIL CDFNT
PUSHES THRU LATE MONDAY. HAVE SLIGHT PREFERENCE FOR GFS GIVEN A
MORE REASONABLE SFC FEATURE DEPICTION...AND THIS IS CLOSE TO THE
SREF SFC PROGS.

FOR TODAY...VEERING H850-900 JET HAS BEEN ORIENTING THE BAND OF
TSRA AHEAD OF THE CDFNT TO A MORE W-E LAYOUT...AND ALTHOUGH LO
LEVEL JET/S IMPACT ON NEW PCPN DEVELOPMENT WILL DIMINISH HEADING
THRU THE MORNING HOURS...SEE HIGH PROBABILITIES FOR TSRA THIS
MORNING FOR AREAS JUST N OF THE STL METRO AREA...S OF KUIN AND FOR
MUCH OF CNTRL MO. SCT COVERAGE PCPN EXPECTED ELSEWHERE...
ESPECIALLY INTO THE ERN OZARKS OF SERN MO. FEEL HEAVY RAIN THREAT
IS NOT AS GREAT FOR THIS PERIOD AS ORIGINALLY THOUGHT...WITH MORE
RAPIDLY MOVING TSRA AND LACK OF MAJOR NEW DEVELOPMENT IN WRN MO.
CANNOT RULE OUT ISOLD HEAVY RAINFALL...BUT THIS SHOULD BE FEW AND
FAR BETWEEN. THINGS WILL RESET HEADING INTO LATE AFTERNOON...WITH
VORT MAX OVER OK ATTM PUSHING INTO WRN MO AND ACTING ON A FRONT
THAT IS EXPECTED TO HAVE STALLED OUT INVOF THE I-70 CORRIDOR. LOOK
FOR NEW ROUND OF TSRA TO DEVELOP INTO CNTRL MO BY LATE THIS
AFTERNOON AND POSSIBLY EXTEND EWD INTO THE STL METRO AREA. PREFER
COOLER END OF MOS TEMPS FOR MAXES BEHIND THE FRONT IN THE FAR NRN
FA...BUT OTHERWISE PREFER THE WARMER END OF MOS WHICH WILL RESULT
IN ANOTHER DAY OF WIDESPREAD TEMPS IN THE 70S...ESPECIALLY
CONSIDERING MANY LOCATIONS ARE ALREADY IN THE UPPER 60S.

FOR TONIGHT/FRIDAY...BETWEEN VORT MAX MOVING OVER THE STALLED OUT
FRONT EARLY TONIGHT AND LO LEVEL JET RE-CRANKING UP...SHOULD SEE
SUBSTANTIAL ROUND OF TSRA MOSTLY FIRE ALONG/N OF FRONTAL BOUNDARY
AFFECTING THE NRN THIRD OF THE FA. CONVECTION WILL BE SLOWER TO
MOVE BY THIS TIME...AND VERY MOIST NATURE OF ATMOSPHERE AND W-E
ORIENTATION OF FRONT AND EXPECTED PCPN...ALONG WITH 6HR FFG
NUMBERS OF 2 INCHES OR LESS FOR MUCH OF NERN MO...LOOKING AT THREAT
FOR FLOODING...AND WILL RE-ISSUE FLOOD POTENTIAL OUTLOOK AGAIN.
CONFIDENCE NOT QUITE HIGH ENOUGH TO ISSUE A SECOND PERIOD FFA AND
WILL ALLOW DAY SHIFT ONE LAST LOOK BEFORE COMMITTING. THINGS
SHOULD WIND DOWN BY FRIDAY MORNING IN THE NRN FA...BUT MAY SEE
WHAT/S LEFT TAKE A SWD DROP BEFORE FULLY EXITING. OTHERWISE...HAVE
LEFT CHANCE POPS IN THRU FRIDAY AFTENOON...ALTHOUGH BEST CHANCES
WILL BE IN THE NRN FA WHERE FRONTAL BOUNDARY EXPECTED TO BE. TEMPS
QUITE CHALLENGING HERE...BUT WENT WITH A MOS BLEND FOR NOW...WITH
ANOTHER DAY IN THE 70S EXPECTED MOST LOCATIONS.

CHANCES FOR TSRA TO CONTINUE THRU THE WEEKEND...BUT MAINLY IN THE
NRN FA WHICH WILL BE CLOSEST TO THE SLOW MOVING W-E ORIENTED FRONT...
OTHERWISE LOW CHANCE OR SLIGHT CHANCE ELSEWHERE. MILD TEMPERATURES
TO ALSO CONTINUE WITH HIGHS IN THE 70S TIL MONDAY.

TES

&&

.AVIATION...
FOR THE 06Z TAFS...NOT TOO MUCH CHANGE IN THINK FROM 00Z TAFS.
COMPLEX OF TSRA OVR NWRN MO AT 05Z IS EXPECTED TO MOVE EWD ACROSS
NRN MO AND REACH KUIN AROUND 11Z. CDFNT IS MOVG SEWD WHICH WILL
CAUSE SHRA AND SCT TSRA TO MOVE INTO KCOU/KSTL/KSUS BETWEEN
10-14Z. FRONT WILL STALL ALG A KMKC-KSTL LINE LATE MORNING AND
AFTERNOON BEFORE LIFTING BACK NWD AS A WRMFNT THURSDAY EVENING.
HAVE KEPT PROB30 GROUPS 18-24Z TOMORROW AT KCOU/KSTL/KSUS TO
REFLECT DEVELOPMENT ALONG THE FRONT AND THEN BETTER CHANCE AT KUIN
TOMORROW EVENING AS LOW LEVEL FORCING INCREASES AS FRONT MOVES
NWD. GRADIENT WINDS WILL SLOWLY DIMINISH OVERNIGHT EXCEPT NEAR
TSRA...AND MAY GO LGT AND VRB WHERE THE FRONT STALLS OUT TOMORROW.

BRITT

&&

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

WFO LSX

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE ST LOUIS MO
515 AM CDT THU MAR 22 2007

ILZ058>060-064-065-069-070-074-079-095>102-MOZ018-019-026-027-
034>036-041-042-047>052-059>065-072>075-084-085-099-231200-
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-
515 AM CDT THU MAR 22 2007

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

.DAY ONE...TODAY AND TONIGHT

THUNDERSTORMS ARE LIKELY...ESPECIALLY FOR AREAS ALONG AND NORTH OF
INTERSTATE 70...WHERE A FRONT IS EXPECTED TO STALL OUT LATER TODAY
AND REMAIN THROUGH TONIGHT. SOME THUNDERSTORMS MAY EXCEED SEVERE
THRESHOLDS WITH HAIL TO NICKEL SIZE AND WIND GUSTS TO 60 MPH. IN
ADDITION...A TORNADO OR TWO CANNOT BE RULED OUT.

HEAVY RAINFALL WILL BE POSSIBLE WITH THE THUNDERSTORMS...ESPECIALLY
TONIGHT IN AREAS NORTH OF INTERSTATE 70. THIS MAY RESULT IN SOME
FLOODING IN THESE AREAS. SEE THE HYDROLOGIC OUTLOOK PRODUCT FOR
SPECIFIC DETAILS.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

THE CHANCE FOR THUNDERSTORMS WILL CONTINUE THROUGH MONDAY AS A
FRONTAL SYSTEM LINGERS OVER THE AREA. THE CHANCE FOR THUNDERSTORMS
IS EXPECTED TO END WITH PASSAGE OF A COLD FRONT LATE ON MONDAY.
ORGANIZED SEVERE THUNDERSTORMS ARE NOT EXPECTED AT THIS TIME.

HEAVY RAINFALL WILL BE POSSIBLE WITH THE THUNDERSTORMS ON FRIDAY
MORNING...ESPECIALLY IN NORTHEAST MISSOURI AND WEST CENTRAL
ILLINOIS. THIS MAY RESULT IN SOME FLOODING IN THESE AREAS. SEE
THE HYDROLOGIC OUTLOOK PRODUCT FOR SPECIFIC DETAILS.

.SPOTTER INFORMATION STATEMENT...

SPOTTERS MAY BE NEEDED...ESPECIALLY FOR AREAS ALONG AND NORTH OF
INTERSTATE 70. IN ADDITION...SPOTTERS ARE ASKED TO RELAY OCCURRENCES
OF FLOODING OR RAINFALL AMOUNTS OF ONE INCH OR GREATER.

TES

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
526 AM CDT THU MAR 22 2007

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

0430 AM     HAIL             1 NNE BETHALTO          38.92N 90.04W
03/22/2007  E0.88 INCH       MADISON            IL   TRAINED SPOTTER

&&

TES