Severe Thunderstorm Warning 1, NWS Des Moines, IA

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DES MOINES IA
411 PM CDT MON APR 28 2003

SHORTER TERM...VERY BUSY AFTN...AND IT LOOKS LIKE IT WILL BE THE NXT
48HRS TOO. XCLNT SYNOPTICS SETTING UP FOR CONVECTION WITH ALL THE
PARAMETERS COMING TOGETHER ACRS SRN NEB/NRN KS INTO SRN IA/NRN MO.
GOOD LOW LVL INFLOW AND UPR SUPPORT WITH SVRL WAVES EJECTING OUT OF
THE WRN TROF. H8 BNDRY ACRS SRN IA VCNTY. IT WILL BOIL DOWN TO THE
MESOSCALE ON PLACEMENT OF BEST SVR RISK WITH CUR INDICATIONS
POINTING TO SWRN QTR OF IA INTO ADJ AREAS OF NEB...MO AND KS.
ELEVATED CONVECTION LIKELY AGN TNGT WITH MCS XPCD TO FIRE TO OUR W
AND ROLL INTO THE STATE. SIMILAR TO ERLY THIS MRNG...BUT WITH MORE
PUNCH. ADDED LRG HAIL TO WORDING IN SW AND SC. OUTFLOW BNDRY FM XPCD
OVRNGT STORMS MAY BE PUSHED SWD TMR FM THE DECAYING MCS...WHICH
WOULD LWR OUR SVR THREAT. DID NOT ADJ THE FCST BASED ON THIS
POSSIBILITY. HOLDING TO PREV FCST THINKING OVERALL ESPECIALLY WITH
H8 BNDRY NOT MOVING ALL THAT MUCH.

LONGER TERM...DAY6/7 PCPN STILL LOOKING GOOD WITH NEARLY ALL LONGER
RANGE MDLS ABT ON THE SAME PAGE. ONLY MINOR CHGS TO TMPS.

.DSM...NONE

MYERS

IAZ004>007-015>017-023>028-033>039-044>050-057>062-070>075-081>086-
092>097-301100-

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE DES MOINES IA
100 PM CDT TUE APR 29 2003

THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL IOWA.

...SEVERE WEATHER POTENTIAL EXISTS IN CENTRAL IOWA LATE TONIGHT AND
WEDNESDAY...

.DAY ONE...TODAY AND TONIGHT

A SLIGHT RISK OF SEVERE THUNDERSTORMS EXISTS ACROSS SOUTHWEST AND
SOUTH CENTRAL IOWA TONIGHT...ESPECIALLY AFTER 10 PM.  SOUTHERLY FLOW
WILL TRANSPORT ADDITIONAL MOISTURE AND INSTABILITY INTO THIS PART OF
THE STATE TONIGHT...FEEDING MULTIPLE CLUSTERS OF THUNDERSTORMS THAT
MOVE IN FROM SOUTHEAST NEBRASKA THIS EVENING.  LARGE HAIL AND
DAMAGING WIND GUSTS WILL BE POSSIBLE WITH SOME OF THESE STORMS.
MODERATE TO STRONG THUNDERSTORMS ARE ALSO POSSIBLE FURTHER NORTH
ACROSS CENTRAL AND NORTHERN IOWA.  RAINFALL AMOUNTS OF ONE HALF TO
ONE INCH ARE POSSIBLE THROUGH WEDNESDAY MORNING.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

A MODERATE RISK OF SEVERE THUNDERSTORMS EXISTS ON WEDNESDAY FOR ALL
OF CENTRAL IOWA...CAPABLE OF VERY LARGE HAIL AND TORNADOES.  THE
HIGHEST THREAT SHOULD RESIDE ACROSS CENTRAL AND SOUTHERN PORTIONS OF
CENTRAL IOWA FROM LATE WEDNESDAY AFTERNOON INTO WEDNESDAY
EVENING...ALTHOUGH SEVERE WEATHER COULD OCCUR THROUGHOUT THE DAY.
LOW PRESSURE TAKING SHAPE IN CENTRAL KANSAS WEDNESDAY WILL DRAW A
STRONG WARM FRONT INTO SOUTHERN IOWA WEDNESDAY AFTERNOON.
SIGNIFICANT DESTABILIZATION OF THE ATMOSPHERE IS EXPECTED SOUTH OF
THE FRONT WEDNESDAY AFTERNOON...LEADING TO DEVELOPMENT OF ISOLATED
TO SCATTERED SUPERCELL THUNDERSTORMS...ESPECIALLY NEAR THE LOW
PRESSURE CENTER AND WARM FRONT.  AS THE LOW MOVES INTO CENTRAL IOWA
WEDNESDAY EVENING...A SQUALL LINE OF THUNDERSTORMS ALONG A COLD
FRONT MAY AFFECT SOUTHERN IOWA LATER WEDNESDAY NIGHT.

.SPOTTER INFORMATION STATEMENT...

MID IOWA SKYWARN AND SPOTTER GROUPS SHOULD BE READY TO ACTIVATE LATE
TONIGHT AND ESPECIALLY ON WEDNESDAY.

&&

MORE INFORMATION CAN BE OBTAINED AT WWW.CRH.NOAA.GOV/DMX (ALL LOWER CASE).

KULA