Severe Thunderstorm Warning 271, NWS Des Moines, IA

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DES MOINES IA
915 PM CDT TUE JUN 15 2004

.SHORT TERM...TNGT
00Z SFC MAP SHOWING CDFNT OVR SE SD.  TSTMS DEVELOPED NEAR BOUNDARY
OVR SERN SD AND MN.  MORE WDSPRD CONVECTION OVER NEBRASKA ALONG
BOUNDARY.  AMS RMNS UNSTABLE OVER WRN IA ATTM.  A FEW SHOWERS OVR SE
IN TROPICAL AMS LIFTING NE.

CONCERN TONIGHT IS TSTMS OVR FA.  DEEP CONVECTION AND AREA OF
PRIMARY CONCERN FOR HEAVY RAIN/SEVERE WEATHER SHOULD REMAIN FOCUSED
TO THE WEST OF IA ON THE NOSE OF LOW-LVL JET.  CDFNT SHUD PUSH INTO
NW LATE TONIGHT.  IA APPEARS TO BE TOO FAR SOUTH TO BENEFIT FM
DYNAMICS ASSOCIATED WITH TAIL OF S/WV TROF OVER SRN CANADA.  TROF
SHOULD BE STRONG ENOUGH TO PUSH BOUNDARY INTO IA OVERNIGHT.  LOW-LVL
JET SUPPORT NOT OVERLY GOOD EITHER FOR CONTINUED CONVECTION (20KTS
OR LESS). WILL KEEP POPS IN NW FA DURG OVERNIGHT HOURS AND DROP TO
THE SOUTHEAST.

NO CHANGES TO FCST ON WEDNESDAY AND WILL KEEP WATCH GOING.

&&

.DMX WATCHES/WARNINGS/ADVISORIES...FLOOD WATCH WED.

&&

JOHNSON

HAZARDOUS WEATHER OUTLOOK...CORRECTION
NATIONAL WEATHER SERVICE DES MOINES IA
555 AM CDT WED JUN 16 2004

IAZ004>007-015>017-023>028-033>039-044>050-057>062-070>075-081>086-
092>097-171059-
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-
500 AM CDT WED JUN 16 2004

THIS HAZARDOUS WEATHER OUTLOOK IS FOR ALL OF CENTRAL IOWA.

.DAY ONE...TODAY AND TONIGHT
A THREAT OF HEAVY RAINFALL AND FLASH FLOODING EXISTS THIS AFTERNOON
AND TONIGHT.  SCATTERED THUNDERSTORMS WILL DEVELOP BEFORE NOON IN
WESTERN AND CENTRAL IOWA...AND SPREAD NORTHEAST THROUGH THE
AFTERNOON.  OTHER STORMS WILL DEVELOP ALONG A COLD FRONT DROPPING
INTO NORTHERN IOWA.  RAINFALL RATES OF 1 TO 3 INCHES PER HOUR...SLOW
MOVEMENT AND TRAINING OF STORMS COULD LEAD TO EXCESSIVE RAINFALL IN
A SHORT PERIOD OF TIME.

THERE IS ALSO A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS
AFTERNOON...INCLUDING A THREAT OF BRIEF ISOLATED TORNADOES.
CONDITIONS ARE FAVORABLE FOR FAST DEVELOPING LANDSPOUT AND MINI-
SUPERCELL TORNADOES.  HAIL IS A LESSOR THREAT.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH MONDAY
ANOTHER PERIOD OF THUNDERSTORMS WITH POTENTIALLY HEAVY RAIN WILL
OCCUR ON THURSDAY...BUT THE RISK OF SEVERE WEATHER IS QUITE LOW.

LOOKING FURTHER AHEAD...THUNDERSTORMS ARE AGAIN POSSIBLE SATURDAY
AND TUESDAY...BOTH WITH SLIGHT RISKS OF SEVERE WEATHER AND HEAVY
RAINFALL.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS POSSIBLE TODAY FOR SEVERE WEATHER...AND FOR
TONIGHT AND THURSDAY PRIMARILY TO REPORT FLOODING OR HEAVY RAIN
TOTALS.  SPOTTERS MAY AGAIN BE NEEDED AGAIN SATURDAY AND
TUESDAY.

KULA