Severe Thunderstorm Warning 105, NWS Des Moines, IA

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DES MOINES IA
315 PM CDT MON MAY 14 2007

.SHORT TERM FORECAST...
MAIN FOCUS WILL BE COLD FRONT MOVING SOUTHEAST THROUGH THE
OVERNIGHT.  MAIN ISSUE IS TIMING AND MOVEMENT.  LEANED TOWARD NAM
BASED ON INITIAL CONDITIONS OF MODELS.  EXPECT ANY DEVELOPMENT WILL
BE INVOF FRONT AS MODELS DEPICT NARROW BAND OF CAPE AND INSTABILITY
MAXES.  LOOKING OVER SOUNDINGS NOT GREAT WIND FIELDS AND NOT MUCH IN
WAY OF SHEAR.  IF ANY SEVERE STORMS DO DEVELOP LIKELY WILL BE HAIL
AND WIND THREATS...TORNADO THREAT MINIMAL. MUCH DRIER AIR FARTHER
BEHIND THIS FRONT SO BELIEVE NORTH WILL BE MUCH COOLER AS DEWPOINTS
DRY OUT WHILE IN THE SOUTH FULL EFFECTS OF DRYING NOT FELT BEFORE
14Z.

.LONG TERM /TONIGHT-SUNDAY/...
FRONT AND ACTIVE CONVECTION SHOULD BE EXITING SERN COUNTIES EARLY IN
DAY ON TUE. POTENTIAL FOR A NARROW STRATIFORM RAIN REGION FOLLOWING
THE LINE ALONG THE FRONT...AND WSWLY LOW LEVEL JET STILL FEEDING
INTO BACK SIDE...SO COULD SEE UP TO ONE HALF INCH RAINFALL AMOUNTS
ALL BEFORE NOON IN FAR SERN COUNTIES. STRONG DRYING THEN FOLLOWS
WITH COLD AIR ADVECTION AND WINDY CONDITIONS...SO A MUCH COOLER DAY
ON TUE. HELD A COUPLE OF DEGREES ABOVE GUIDANCE IN THE SOUTH HALF
DUE TO MILD START EARLY. QUIET ON TUE NIGHT THEN A QUICK MOVING
SECONDARY COOL FRONT PASSES THROUGH ON WED. MOISTURE WILL BE QUITE
LIMITED BUT THERE MAY BE ENOUGH HEATING IN ADVANCE OF THE FRONT
COMBINED WITH COLD AIR ALOFT TO PRODUCE HI-BASED SHOWERS SOUTH OF
I-80 WED AFTERNOON. LAPSE RATES WILL BE STEEP SO THIS WOULD LIKELY
BE A LOT OF VIRGA AND BRIEF WIND GUSTS AND VERY LOW IF ANY QPF.

HI PRESSURE SETTLES OVER THE ARE FOR A PLEASANT THURSDAY THEN A
GRADUAL WARMUP THROUGH THE WEEKEND AS IOWA STAYS IN THE WARM SECTOR
AND DRY. BOUNDARY WILL APPROACH SRN MN SATURDAY NIGHT...BUT ANY
CONVECTION ASSOCIATED WITH IT IS EXPECTED TO REMAIN WELL N OF IA.
SOUTH FLOW CONTS INTO MON...AND WITH A COLD FRONT APPROACHING FROM
THE WEST...INSERTED THE FIRST CHANCE FOR THUNDERSTORMS AGAIN ON
MONDAY. HOWEVER...AT THIS POINT ANY RAIN APPEARS TO BE MORE LIKELY
TOWARD TUE...BUT THATS A LONG WAY OUT.

&&

.AVIATION...
TIMING OF THUNDERSTORM DEVELOPMENT AND MOVEMENT OF COLD FRONT
THROUGH THE STATE MAIN ISSUES AFFECTING AVIATION WEATHER TONIGHT.
APPEARS ANY CLOUDS AND RAIN WILL BE NEAR THE COLD FRONT AND MOST OF
THAT CLOUDINESS WILL BE VFR LIKELY ABOVE 5000 FEET.  THUNDERSTORMS
WILL PRODUCE MVFR CEILINGS LESS THAN 3000 FEET AND VISIBILITY 3-5
MILES.  SLOW IMPROVEMENT TOWARD MORNING FROM NORTHWEST WITH CEILINGS
REMAINING MVFR.

&&

.DMX WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY EXPIRES AT 6 PM CDT THIS EVENING FOR COUNTIES
INCLUDING HIGHWAY 30 AND NORTHWARD.

&&

SHORT TERM/AVIATION...FORSTER
LONG TERM...JUNGBLUTH

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE DES MOINES IA
332 PM CDT MON MAY 14 2007

IAZ004>007-015>017-023>028-151100-
EMMET-KOSSUTH-WINNEBAGO-WORTH-PALO ALTO-HANCOCK-CERRO GORDO-
POCAHONTAS-HUMBOLDT-WRIGHT-FRANKLIN-BUTLER-BREMER-
332 PM CDT MON MAY 14 2007

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL IOWA
ALONG AND NORTH OF HIGHWAY 3.

.DAY ONE...TONIGHT

SCATTERED THUNDERSTORMS WILL DEVELOP THIS EVENING AND BECOME MORE
NUMEROUS OVERNIGHT. THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS
WHICH COULD PRODUCE LARGE HAIL UP TO THE SIZE OF GOLF BALLS AND
DAMAGING WIND.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY

ISOLATED TO SCATTERED NON SEVERE THUNDERSTORMS ARE POSSIBLE TUESDAY
MORNING EAST OF LINE FROM CLARION TO NORTHWOOD.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED THIS EVENING AND OVERNIGHT.

IAZ033>039-044>050-057>062-070>075-081>086-092>097-151100-
SAC-CALHOUN-WEBSTER-HAMILTON-HARDIN-GRUNDY-BLACK HAWK-CRAWFORD-
CARROLL-GREENE-BOONE-STORY-MARSHALL-TAMA-AUDUBON-GUTHRIE-DALLAS-
POLK-JASPER-POWESHIEK-CASS-ADAIR-MADISON-WARREN-MARION-MAHASKA-
ADAMS-UNION-CLARKE-LUCAS-MONROE-WAPELLO-TAYLOR-RINGGOLD-DECATUR-
WAYNE-APPANOOSE-DAVIS-
332 PM CDT MON MAY 14 2007

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL IOWA.

.DAY ONE...TONIGHT

SCATTERED THUNDERSTORMS WILL MOVE SOUTH THROUGH THE AREA LATER
TONIGHT. THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS WHICH
COULD PRODUCE LARGE HAIL UP TO THE SIZE OF GOLF BALLS AND DAMAGING
WIND...MAINLY NORTH OF INTERSTATE 80.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY

ISOLATED TO SCATTERED THUNDERSTORMS ARE POSSIBLE TUESDAY MORNING
ACROSS MUCH OF THE AREA. ISOLATED THUNDERSTORMS COULD LINGER OVER
FAR SOUTHEASTERN AREAS INTO TUESDAY AFTERNOON. NO SEVERE WEATHER
WEATHER IS ANTICIPATED.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED LATER TONIGHT.

FORSTER

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
524 PM CDT MON MAY 14 2007

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

0522 PM     HAIL             3 SW DOW CITY           41.90N 95.54W
05/14/2007  E1.00 INCH       CRAWFORD           IA   TRAINED SPOTTER

&&

STEACHOU

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
549 PM CDT MON MAY 14 2007

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

0544 PM     HAIL             4 S DOW CITY            41.87N 95.49W
05/14/2007  E0.75 INCH       CRAWFORD           IA   TRAINED SPOTTER

&&

STEACHOU

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
646 PM CDT MON MAY 14 2007

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

0637 PM     HAIL             5 NNE LEHIGH            42.42N 94.02W
05/14/2007  E0.88 INCH       WEBSTER            IA   TRAINED SPOTTER

&&

STEACHOU