Severe Thunderstorm Warning 3, NWS Des Moines, IA

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DES MOINES IA
327 AM CST WED MAR 24 2004

.DISCUSSION...

MAIN FORECAST CHALLENGE CONTINUES TO BE CONVECTIVE PERIODS.
ZONAL FLOW IN PLACE OVER CONUS THIS MORNING WITH BULK OF MAIN UPPER
JET ENERGY WELL REMOVED TO THE NE US. A WEAK VORTICITY MAXIMUM IS
DRIFTING EAST OVER NW IOWA...PROVIDING ADDITIONAL ENHANCED LIFT
FOR ELEVATED MULTICELL CLUSTER THUNDERSTORMS OVER THE NCNTRL CWA
EARLY THIS MORNING.  THE STORMS HAVE LITTLE VERTICAL EXTENT WITH
WEAK CAPES 400 J/KG PROGGED IN RUC20 AND ARE INITIATING ALONG IN A
NARROW BAND OF WEAK MID LEVEL INSTABILITY (STABLE LOW LEVELS) AT THE
LEADING EDGE OF A BOUNDARY LAYER JET MAX. WEAK BUOYANCY ALSO EVIDENT
IN THE LOW LIGHTNING FREQUENCY OF 2-5 STRIKES PER MINUTE BUT
FREEZING LEVELS SUFFICIENT TO SUPPORT MARGINALLY SEVERE HAIL WITH
STRONGEST UPDRAFTS.

RUC HAS TREND GOING GOOD AND REMOVES PRECIPITATION TO EAST OF CWA
THIS MORNING...WITH EASTWARD DISPLACEMENT OF THE MID LEVEL ENERGY.
WILL LEAVE IN SOME LOW POPS IN THE EARLY MORNING WITH HIGHER
POPS/TSRA IN NE. IR COLD IR CLOUD TOPS ARE COINCIDENT WITH THE
EASTWARD MOVING ENERGY AND DONT SEE A PRESENT FORCING MECHANISM FOR
THIS AFTERNOON SO WILL GO WITH A DRY FORECAST AFTER THIS MORNING.

SHOULD SEE SOME OF THE WARMEST TEMPS OF THE YEAR SO FAR THIS
AFTERNOON WITH SW FLOW...GOOD MIXING IN LOWEST LEVELS AND OVERNIGHT
TEMPS IN THE LOW 50S SETTING STAGE FOR WARMING TO 70 AND ABOVE
THROUGH THE SOUTHERN HALF OF THE CWA TODAY.

LITTLE CHANGE TO OUTER PERIODS OF FORECAST WITH MUCH UNCERTAINTY TO
EXACT TIMING OF CONVECTION. PATTERN WILL CONTINUE TO BE
INCREASINGLY  UNSTABLE WITH ETA SHOWING A PERIOD OF DECENT MOISTURE
TRANSPORT NORTHWARD RESULTING IN HIGHER DEW POINTS TO NEAR 60
DEGREES BY THURSDAY NIGHT WHEN NEXT CONVECTION PERIOD IS IN THE
FORECAST.

&&

.DMX WATCHES/WARNINGS/ADVISORIES...NONE.

&&

MR

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE DES MOINES IA
355 AM CST WED MAR 24 2004

IAZ004>007-015>017-023>028-033>039-044>050-057>062-070>075-081>086-
092>097-251159-
ADAIR-ADAMS-APPANOOSE-AUDUBON-BLACK HAWK-BOONE-BREMER-BUTLER-CALHOUN-
CARROLL-CASS-CERRO GORDO-CLARKE-CRAWFORD-DALLAS-DAVIS-DECATUR-EMMET-
FRANKLIN-GREENE-GRUNDY-GUTHRIE-HAMILTON-HANCOCK-HARDIN-HUMBOLDT-
JASPER-KOSSUTH-LUCAS-MADISON-MAHASKA-MARION-MARSHALL-MONROE-
PALO ALTO-POCAHONTAS-POLK-POWESHIEK-RINGGOLD-SAC-STORY-TAMA-TAYLOR-
UNION-WAPELLO-WARREN-WAYNE-WEBSTER-WINNEBAGO-WORTH-WRIGHT-
355 AM CST WED MAR 24 2004

THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL IOWA.

.DAY ONE...TONIGHT.

SCATTERED THUNDERSTORMS ARE POSSIBLE ACROSS CENTRAL IOWA LATE
TONIGHT...MAINLY AFTER 2AM.  ALTHOUGH THE STORMS ARE NOT EXPECTED TO
BE SEVERE...SOME MARGINALLY SEVERE HAIL MAY OCCUR.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY.

ADDITIONAL CHANCES FOR THUNDERSTORMS ARE EXPECTED ACROSS ALL OF
CENTRAL IOWA ON THURSDAY INTO THURSDAY EVENING.  THERE IS A SLIGHT
RISK OF SEVERE THUNDERSTORMS DURING THE DAY ON THURSDAY WITH THE
MAIN THREAT OF SEVERE WEATHER COMING FROM LARGE HAIL.

OTHER CHANCES OF THUNDERSTORMS WILL CONTINUE FROM FRIDAY NIGHT INTO
SUNDAY AS SEVERAL UPPER LEVEL SYSTEM PASS THROUGH THE MIDWEST.  THE
THREAT FOR ISOLATED TO SCATTERED SEVERE STORMS WILL PERSIST INTO THE
WEEKEND BEFORE THE THUNDERSTORMS PUSH EAST BY SUNDAY NIGHT.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED ON THURSDAY INTO THURSDAY EVENING.
SPOTTERS MAY ALSO BE NEEDED AT VARIOUS TIMES FROM FRIDAY NIGHT INTO
SUNDAY AS WELL.

COGIL

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
213 AM CST WED MAR 24 2004

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

0155 AM     HAIL             5 SE FORT DODGE         42.46N 94.11W
03/24/2004  0.75 INCH        WEBSTER            IA   LAW ENFORCEMENT

            REPORTED BY WEBSTER COUNTY SHERIFFS OFFICE.

&&

MR