Severe Thunderstorm Warning 274, NWS Des Moines, IA

000 
WWUS53 KDMX 131134
SVSDMX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
633 AM CDT MON AUG 13 2007

IAC015-131145-
/O.CON.KDMX.SV.W.0274.000000T0000Z-070813T1145Z/
BOONE IA-
633 AM CDT MON AUG 13 2007

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 645 AM CDT
FOR SOUTHERN BOONE COUNTY...

AT 632 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING PENNY SIZE HAIL. 
THIS STORM WAS LOCATED NEAR MADRID...OR ABOUT 26 MILES NORTHWEST OF
DES MOINES...MOVING SOUTHEAST AT 25 MPH.

THE SEVERE THUNDERSTORM WILL OTHERWISE REMAIN OVER MAINLY RURAL AREAS
OF THE INDICATED COUNTY.

THE STORM IS BEGINNING TO WEAKEN AND THE THREAT FOR LARGE HAIL IS 
DIMINISHING. 

IF YOU ARE IN THE PATH OF THIS STORM...PREPARE IMMEDIATELY FOR LARGE
HAIL...DAMAGING WINDS AND DEADLY CLOUD TO GROUND LIGHTNING. PEOPLE
OUTSIDE SHOULD MOVE TO A SHELTER...PREFERABLY INSIDE A STRONG
BUILDING BUT AWAY FROM WINDOWS.

LAT...LON 4186 9371 4186 9399 4203 9406 4209 9371
TIME...MOT...LOC 1133Z 323DEG 24KT 4191 9381

$$

DONAVON

000 
WWUS53 KDMX 131142
SVSDMX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
642 AM CDT MON AUG 13 2007

IAC015-131152-
/O.EXP.KDMX.SV.W.0274.000000T0000Z-070813T1145Z/
BOONE IA-
642 AM CDT MON AUG 13 2007

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHERN BOONE COUNTY EXPIRES
AT 645 AM CDT...

AT 641 AM CDT...WEATHER SERVICE DOPPLER RADAR INDICATED THAT THE
THUNDERSTORMS WHICH PROMPTED THE WARNING HAVE WEAKENED...AND NO
LONGER POSE AN IMMEDIATE THREAT TO LIFE OR PROPERTY. THEREFORE...THE
SEVERE THUNDERSTORM WARNING WILL BE ALLOWED TO EXPIRE.

LAT...LON 4186 9371 4186 9399 4203 9406 4209 9371
TIME...MOT...LOC 1142Z 323DEG 24KT 4186 9376

$$

DONAVON

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DES MOINES IA
310 AM CDT MON AUG 13 2007

.SHORT TERM...TODAY
EVENING CONVECTIVE COMPLEX...MCC...HAS MOVED OUT OF THE AREA AND IN
THE WAKE OF COMPLEX WARM AND HUMID AIR REMAINS. ADDITIONAL
THUNDERSTORMS ARE POPPING UP BEHIND THE COMPLEX...MAINLY WIDELY
SCATTERED. SUBJECTIVE SFC BOUNDARY CONTINUES TO SHOW LOW PRESSURE
OVER MONTANA WITH SFC STATIONARY BOUNDARY EXTENDING SOUTHEAST ACROSS
NEBRASKA TO NEAR KANSAS CITY. WIDESPREAD MOISTURE POOLING CONTINUES
ALONG THE FRONT...THOUGH HIGHEST MOISTURE CONTINUES SITUATED FROM
NEAR NORTHERN MO TO CENTRAL IL AT 03Z. INTERESTING AND ACTIVE
WEATHER TO CONTINUE OVER THE REGION. THETAE ADVECTION ALREADY FIRING
STORMS ATTM OVER THE FORECAST AREA AND THESE SHOULD WORK NORTHEAST
/EAST THIS MORNING. SFC BOUNDARY AND MOISTURE POOL TO MAKE LITTLE
EASTWARD PROGRESS WITH SOME ADDITIONAL SFC MOISTURE CONVERGENCE
ALONG THE WARM FRONT AND APPROACHING COOL FRONT LATER THIS
AFTERNOON/EVE. GFS/NAM CONTINUES TO INCREASE MLCAPES TO 3800/5400
J/KG RESPECTIVELY BY 00Z.

.MID/LONG TERM...TONIGHT THROUGH SUNDAY
AFTER EARLY MORNING CONVECTION DIMINISHES...DAYTIME TODAY TO REMAIN
RELATIVELY CAPPED ALOFT. BY THIS EVENING NMM WRF MODEL DEVELOPING A
SUBSTANTIAL MCS ALONG TRIPLE POINT AROUND 00-02Z OVER MN AND FORCING
IT SOUTHEAST ALONG THE MOISTURE AXIS OVER NORTHEAST IOWA. MOISTURE
TRANSPORT MAXIMIZED OVER FAR NORTHEAST WITH CORFIDIS TRACKING
COMPLEX DUE SOUTH. WRF MODEL BACKBUILDS INTO WARM SECTOR. HAVE
ADJUSTED POPS UPWARD TO LIKELY CATEGORY NORTHEAST AND HIGHER CHANCE
OVERNIGHT IN THIS AREA BACK TO I35. ALSO OF NOTE...BULK SHEAR
INCREASES DRAMATICALLY OVERNIGHT NORTHEAST INTO WISCONSIN AS SHORT
WAVE AND SFC LOW APPROACHES FROM THE WEST AND NORTHWEST. SUPERCELLS
WITH WIND/HAIL MAIN THREAT AND POSSIBLE TORS ALONG WARM FRONT
BOUNDARY...DEPENDING ON INITIATION TIME. ACTIVITY TO REMAIN OVER THE
REGION OVERNIGHT AND DIMINISH BY TUES AM. LOOKING WEST
TUESDAY...HAVE INTRODUCED POPS AS YET ANOTHER WAVE APPROACHES AND
BOUNDARY BECOMES MORE ACTIVE DURING THE EVENING HOURS. INITIATION
MORE LIKELY WITH NOCTURNAL JET INCREASE...BUT HAVE ADDED SOME PM
POPS WITH INCREASING INSTABILITY. FRONT TO REMAIN ACTIVE THROUGH WED
AS HIGH BUILDS SOUTH AND PUSHES THE FRONT THROUGH THE STATE BY THURS
MORNING. RELATIVELY COOL AIRMASS WILL MAKE IT INTO AREA LATE
THURSDAY AND FRIDAY...POSSIBLY LINGERING INTO THE WEEKEND. THOUGH
TIMING AND PLACEMENT STILL A QUESTION MARK...MODELS CONTINUE TO
INDICATE INCREASING FRONTOGENESIS WITH MOISTURE RETURN SOUTH...LOW
APPROACHING...AND INCREASING SOUTHERLY JET ALL BODE TOWARD A WET
PERIOD FOR FRI/SAT WITH POTENTIAL FOR HEAVY RAIN. GIVEN ITS STILL 5
DAYS AWAY...CURRENT POP CHANCES COVER SITUATION WELL.

&&

.AVIATION...13/06Z

THUNDERSTORM CHANCES CONTINUE OVERNIGHT EVEN WITH EARLIER MCS HAS
ALTERING THE STABILITY OF ATMOSPHERE OVER IA.  NOT SURE 00Z MODELS
ARE COMPLETELY CAPTURING THIS BUT WOULD NOT BE SURPRISE TO SEE SOME
-TSRA DEVELOP 08-12Z...OTHERWISE...VFR CONDITIONS EXPECTED THROUGH
TAF PERIOD...SAVE FOR SMALL CHANCES OF MVFR VSBY 08-14Z.

&&

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

&&

SHORT TERM...REV
MID/LONG TERM...REV
AVIATION...MOYER

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE DES MOINES IA
529 AM CDT MON AUG 13 2007

IAZ004>007-015>017-023>028-037>039-049-050-062-075-141045-
EMMET-KOSSUTH-WINNEBAGO-WORTH-PALO ALTO-HANCOCK-CERRO GORDO-
POCAHONTAS-HUMBOLDT-WRIGHT-FRANKLIN-BUTLER-BREMER-HARDIN-GRUNDY-
BLACK HAWK-MARSHALL-TAMA-POWESHIEK-MAHASKA-
529 AM CDT MON AUG 13 2007

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTHERN AND CENTRAL
IOWA.

.DAY ONE...TODAY AND TONIGHT

ISOLATED MAINLY NON SEVERE THUNDERSTORMS ARE POSSIBLE THIS MORNING.
MORE WIDESPREAD AND POTENTIALLY SEVERE STORMS ARE EXPECTED THIS
EVENING AFTER 6 PM AND WILL CONTINUE PAST MIDNIGHT EAST OF INTERSTATE
35. THE MAIN THREAT FROM THESE STORMS WILL BE WINDS IN EXCESS OF
70 MPH ALONG WITH LARGE HAIL. AN ISOLATED TORNADO IS ALSO POSSIBLE
WITHIN STORMS THAT DEVELOP ALONG A WARM FRONTAL BOUNDARY WHICH WILL
STRETCH ACROSS NORTHERN IOWA THIS EVENING.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY

PERIODS OF THUNDERSTORMS ARE EXPECTED TUESDAY EVENING THROUGH
WEDNESDAY AND AGAIN LATE THURSDAY THROUGH SUNDAY. SOME OF THE
STORMS TUESDAY AFTERNOON AND EVENING MAY BE SEVERE. SOME OF THE
STORMS LATE THURSDAY INTO FRIDAY MAY PRODUCE LOCALLY HEAVY RAINFALL.
THOUGH THE THREAT FOR ADVERSE WEATHER IS INCREASING FOR THESE TWO
PERIODS IN PARTICULAR...IT IS TOO EARLY TO DETERMINE THE LOCATION
OF GREATEST RISK.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL NOT BE NEEDED THIS MORNING...BUT IS
BECOMING MORE LIKELY THIS EVENING ACROSS THE OUTLOOKED AREA.
ADDITIONALLY...SPOTTER ACTIVATION MAY BE NEEDED LATE TUESDAY
AFTERNOON AND EVENING.

IAZ033-044-045-057-058-070-071-081-082-092-093-141045-
SAC-CRAWFORD-CARROLL-AUDUBON-GUTHRIE-CASS-ADAIR-ADAMS-UNION-
TAYLOR-RINGGOLD-
529 AM CDT MON AUG 13 2007

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF WEST CENTRAL
AND SOUTHERN IOWA.

.DAY ONE...TODAY AND TONIGHT

HOT AND HUMID WEATHER IS EXPECTED TODAY WITH HEAT INDEX READINGS
APPROACHING THE 102 TO 107 RANGE DURING THE AFTERNOON AND EARLY
EVENING HOURS. ISOLATED THUNDERSTORMS ARE POSSIBLE THIS LATER THIS
EVENING WITH A FEW STORMS BEING SEVERE WITH WIND AND HAIL BEING
THE MAIN THREAT.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY

PERIODS OF THUNDERSTORMS ARE EXPECTED TUESDAY EVENING THROUGH
WEDNESDAY AND AGAIN LATE THURSDAY THROUGH SUNDAY. SOME OF THE
STORMS TUESDAY AFTERNOON AND EVENING MAY BE SEVERE. SOME OF THE
STORMS LATE THURSDAY INTO FRIDAY MAY PRODUCE LOCALLY HEAVY
RAINFALL. THOUGH THE THREAT FOR ADVERSE WEATHER IS INCREASING FOR
THESE TWO PERIODS IN PARTICULAR...IT IS TOO EARLY TO DETERMINE THE
LOCATION OF GREATEST RISK.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL NOT BE NEEDED THIS MORNING. SPOTTER
ACTIVATION MAY BE NEEDED LATE TUESDAY AFTERNOON AND EVENING.

IAZ034>036-046>048-059>061-072>074-083>086-094>097-141045-
CALHOUN-WEBSTER-HAMILTON-GREENE-BOONE-STORY-DALLAS-POLK-JASPER-
MADISON-WARREN-MARION-CLARKE-LUCAS-MONROE-WAPELLO-DECATUR-WAYNE-
APPANOOSE-DAVIS-
529 AM CDT MON AUG 13 2007

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL AND SOUTHERN IOWA.

.DAY ONE...TODAY AND TONIGHT

WIDELY SCATTERED...MAINLY NON SEVERE THUNDERSTORMS ARE EXPECTED THIS
MORNING. HOT AND HUMID WEATHER IS EXPECTED THIS AFTERNOON WITH
HEAT INDEX READINGS RANGING FROM 100 TO 105 DEGREES. SCATTERED AND
POTENTIALLY SEVERE STORMS ARE EXPECTED AFTER 8 PM GENERALLY NORTH
OF HIGHWAY 30 LATER THIS EVENING AND WILL CONTINUE PAST MIDNIGHT
EAST OF INTERSTATE 35. THE MAIN THREAT FROM THESE STORMS WILL BE
WINDS IN EXCESS OF 70 MPH ALONG WITH LARGE HAIL.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY

PERIODS OF THUNDERSTORMS ARE EXPECTED TUESDAY EVENING THROUGH
WEDNESDAY AND AGAIN LATE THURSDAY THROUGH SUNDAY. SOME OF THE
STORMS TUESDAY AFTERNOON AND EVENING MAY BE SEVERE. SOME OF THE
STORMS LATE THURSDAY INTO FRIDAY MAY PRODUCE LOCALLY HEAVY
RAINFALL. THOUGH THE THREAT FOR ADVERSE WEATHER IS INCREASING FOR
THESE TWO PERIODS IN PARTICULAR...IT IS TOO EARLY TO DETERMINE THE
LOCATION OF GREATEST RISK.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL NOT BE NEEDED THIS MORNING...BUT IS
BECOMING MORE LIKELY THIS EVENING ACROSS NORTHERN PORTIONS OF THE
OUTLOOKED AREA. ADDITIONALLY...SPOTTER ACTIVATION MAY BE NEEDED
LATE TUESDAY AFTERNOON AND EVENING.

REV