Severe Thunderstorm Warning 178, NWS Des Moines, IA

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DES MOINES IA
145 PM CDT SUN AUG 6 2000

SHORT TERM...
CELLS ERUPTING QUICKLY ALONG BOUNDARY, WITH HAIL AND MICROBURSTS THE
MAIN THREAT AND HP SUPERCELL STRUCTURES POSSIBLE.  WILL ACCOUNT FOR
ANY STORMS IN THE SE CWA, BUT OTHERWISE A DRY FORECAST TONIGHT.
RETURN FLOW WILL NOT GET GOING FAST ENOUGH TO GET WAA PRECIP GOING
IN OUR CWA, PERHAPS IN FAR WESTERN IA.  FOG AGAIN A PROBABILITY IN
SOUTHERN ZONES.  TEMPS RATHER CONSISTENT ON GUIDANCE AND LOOK RATHER
GOOD.

LONGER TERM...
DO NOT FORSEE MUCH CHANGE TO GOING FORECASTS, WITH HEAVY RAIN THREAT
NEXT 2 EVENINGS/NIGHTS.  SEVERE THREAT NOT GOING AWAY EITHER WITH
SOUTHERN EDGE OF STRONGER WESTERLIES, LLJ AND HIGH CAPES
CONTRIBUTING.  MESOETA AND AVN CONSISTENT ON DIFFERENT POSITIONING
OF MCS DEVELOPMENT, WITH AVN NOT AS BULLISH WITH AMOUNTS.  FAVORING
ETAS FURTHER S POSITION IN IA AS WE WOULD NEED A STRONGER SHORTWAVE
TO GET THE WARM FRONT N THROUGH IA.  PWATS EXCEED 2 INCHES AGAIN
MONDAY EVENING WITH 40KT LLJ.  ETA SUGGESTS DEVELOPMENT BY 00Z IN
FACT.  SHOULD HAVE DAYTIME WEAKENING, AND RESURGENCE TUESDAY EVENING
AGAIN, WITH INSTABILITY A BIT HIGHER YET.  TEMPS SHOULD WARM TO NEAR
90 S AND INTO THE MID 80S BOTH DAYS.  LOWS IN THE M60S TO AROUND 70.

EXTENDED...
WILL GO WITH A DRY FORECAST ON THU/FRI AS UPPER RIDGE BUILDS.
NORTHERLY FLOW WILL CONTINUE TO BRING SHORTWAVES DOWN, SO CONFIDENCE
NOT THAT GREAT.  EVEN LONGER OUT, RIDGE HAS A HARD TIME BUILDING N
PAST NEXT WEEKEND.  VERY WARM AND HUMID WEATHER THROUGHOUT.

.DSM...NONE
KULA

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
1006 AM CDT SUN AUG 06 2000

TIME(CDT)  .....CITY LOCATION..... STATE  ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0940 PM    6 N BRIDGEWATER           IA   2.5 INCH HAIL
08/05/00   ADAIR                          REPORTED BY PUBLIC.

IAZ049-050-061-062-073>075-082>086-092>097-062300-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
1259 PM CDT SUN AUG 6 2000

HAZARD--SCATTERED THUNDERSTORMS...A FEW OF WHICH MAY BE SEVERE WITH
LARGE HAIL...DAMAGING WINDS AND HEAVY RAINS.

AREA OF CONCERN--SOUTH OF A LINE THROUGH MARSHALLTOWN TO DES MOINES
TO CRESTON.

TIMING DETAILS--REST OF THIS AFTERNOON.

METEOROLOGICAL COMMENTS--A COLD FRONT PUSHING INTO AN AIRMASS WITH
DEWPOINTS IN THE MIDDLE 70S WILL AID IN THE DEVELOPMENT OF ISOLATED
SEVERE THUNDERSTORMS. SURFACE BASED CAPES ARE EXCEEDING 4OOO J/KG
WITH PRECIPITABLE WATER VALUES NEAR TWO INCHES. THERE IS A PUNCH OF
DRIER MID LEVEL AIR ARRIVING AS WELL...SO THE INGRIDENTS FOR SEVERE
WEATHER OVER THE SOUTHEAST HALF OF IOWA WILL BE AVAILABLE THE REST OF
THE AFTERNOON. BY LATER THIS AFTERNOON...MOST OF THE ACTIVITY SHOULD
BE FARTHER TO THE EAST IN SOUTHEAST IOWA.

SPOTTER PLANNING--ACTIVITATION WILL LIKELY BE REQUIRED BEFORE 3 PM IN
PARTS OF CENTRAL AND SOUTH CENTRAL IOWA.

MYERS

IAZ049-050-061-062-073>075-082>086-092>097-062300-

CENTRAL IOWA THUNDERSTORM OUTLOOK
NATIONAL WEATHER SERVICE DES MOINES IA
100 PM CDT SUN AUG 6 2000

HAZARD--SCATTERED THUNDERSTORMS...A FEW OF WHICH MAY BE SEVERE WITH
LARGE HAIL...DAMAGING WINDS AND HEAVY RAINS.

AREA OF CONCERN--SOUTH OF A LINE THROUGH MARSHALLTOWN TO DES MOINES
TO CRESTON.

TIMING DETAILS--REST OF THIS AFTERNOON.

METEOROLOGICAL COMMENTS--A COLD FRONT PUSHING INTO AN AIRMASS WITH
DEWPOINTS IN THE MIDDLE 70S WILL AID IN THE DEVELOPMENT OF ISOLATED
SEVERE THUNDERSTORMS. SURFACE BASED CAPES ARE EXCEEDING 4OOO J/KG
WITH PRECIPITABLE WATER VALUES NEAR TWO INCHES. THERE IS A PUNCH OF
DRIER MID LEVEL AIR ARRIVING AS WELL...SO THE INGRIDENTS FOR SEVERE
WEATHER OVER THE SOUTHEAST HALF OF IOWA WILL BE AVAILABLE THE REST OF
THE AFTERNOON. BY LATER THIS AFTERNOON...MOST OF THE ACTIVITY SHOULD
BE FARTHER TO THE EAST IN SOUTHEAST IOWA.

SPOTTER PLANNING--ACTIVITATION WILL LIKELY BE REQUIRED BEFORE 3 PM IN
PARTS OF CENTRAL AND SOUTH CENTRAL IOWA.

MYERS