Severe Thunderstorm Warning 81, NWS Des Moines, IA

540 
WWUS53 KDMX 241758
SVSDMX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
1258 PM CDT WED JUN 24 2015

IAC027-047-161-241830-
/O.CON.KDMX.SV.W.0081.000000T0000Z-150624T1830Z/
CRAWFORD IA-CARROLL IA-SAC IA-
1258 PM CDT WED JUN 24 2015

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 130 PM CDT
FOR CRAWFORD...WESTERN CARROLL AND SAC COUNTIES...

AT 1258 PM CDT...A SEVERE THUNDERSTORM WAS LOCATED 10 MILES SOUTHWEST
OF LAKE VIEW...OR 15 MILES NORTHEAST OF DENISON...MOVING EAST AT 60
MPH.

HAZARD...60 MPH WIND GUSTS AND NICKEL SIZE HAIL. 

SOURCE...RADAR INDICATED. 

IMPACT...EXPECT DAMAGE TO ROOFS...SIDING AND TREES. 

LOCATIONS IMPACTED INCLUDE...
CARROLL...DENISON...SAC CITY...MANNING...LAKE VIEW...ODEBOLT...BLACK
HAWK LAKE...SCHLESWIG...WALL LAKE...MANILLA...SCHALLER...EARLY...DOW
CITY...CHARTER OAK...ARCADIA...BREDA...VAIL...TEMPLETON...AUBURN AND
WESTSIDE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A
BUILDING.

TO REPORT SEVERE WEATHER CONTACT YOUR NEAREST LAW ENFORCEMENT AGENCY.
THEY WILL SEND YOUR REPORT TO THE NATIONAL WEATHER SERVICE OFFICE IN
DES MOINES .

LARGE HAIL AND DAMAGING WINDS AND CONTINUOUS CLOUD TO GROUND
LIGHTNING IS OCCURRING WITH THIS STORM. MOVE INDOORS IMMEDIATELY.
LIGHTNING IS ONE OF NATURES LEADING KILLERS. REMEMBER...IF YOU CAN
HEAR THUNDER...YOU ARE CLOSE ENOUGH TO BE STRUCK BY LIGHTNING.

TORRENTIAL RAINFALL IS OCCURRING WITH THIS STORM...AND MAY LEAD TO
FLASH FLOODING. DO NOT DRIVE YOUR VEHICLE THROUGH FLOODED ROADWAYS.

&&

LAT...LON 4221 9567 4221 9532 4247 9532 4248 9539
      4251 9539 4256 9492 4187 9481 4187 9567
TIME...MOT...LOC 1758Z 263DEG 51KT 4217 9514 

HAIL...0.88IN
WIND...60MPH
 
$$

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AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DES MOINES IA
628 AM CDT WED JUN 24 2015

.SHORT TERM /TODAY/...
ISSUED AT 421 AM CDT WED JUN 24 2015

A COMPLEX AND RELATIVELY LOW CONFIDENCE CONVECTIVE EVOLUTION
DOMINATES TODAYS FORECAST. CURRENTLY A SURFACE HIGH PRESSURE AREA IS
STILL DOMINATING MOST OF IOWA...HOWEVER THE NOCTURNAL LOW LEVEL JET
HAS GENERATED A PERSISTENT BAND OF ELEVATED THUNDERSTORMS TRAINING
ALONG A PATH FROM AROUND DENISON TO GRINNELL...PLUS ANOTHER COUPLE
OF STORM CLUSTERS IN CENTRAL AND EASTERN NEBRASKA. THIS ACTIVITY
WILL CONTINUE TO PROGRESS SLOWLY EASTWARD ACROSS OUR FORECAST AREA
PAST SUNRISE AND POSSIBLY INTO THE LATE MORNING. MEANWHILE...A
COMPACT BUT ENERGETIC 500 MB SHORTWAVE APPROACHING FROM THE HIGH
PLAINS HAS RESULTED IN THE DEVELOPMENT OF A SURFACE LOW PRESSURE
AREA CURRENTLY LOCATED ALONG THE CENTRAL KANSAS/NEBRASKA
BORDER...WITH AN ATTENDANT WARM FRONT EXTENDING EAST SOUTHEASTWARD
TO JUST SOUTH OF KANSAS CITY. MOST PROGNOSTIC MODELS ARE SURGING
THIS WARM FRONT NORTHWARD ACROSS IOWA TODAY...HOWEVER...IT REMAINS
TO BE SEEN HOW THE COMBINATION OF THE MORNING CONVECTION AND ZONAL
STEERING FLOW MAY RETARD THE PROGRESS OF THE FRONT. THIS WILL BE
CRITICAL LATER...BECAUSE A CAPPING INVERSION IN THE AFTERNOON WILL
LIKELY BREAK BY LATE AFTERNOON/EVENING IN THE WARM SECTOR AHEAD OF
THE SURFACE LOW AND ANY THUNDERSTORMS THAT DEVELOP ALONG THE WARM
FRONTAL ZONE WILL BE IN AN ENVIRONMENT THAT IS VERY FAVORABLE FOR
SIGNIFICANT SEVERE WEATHER. MOST OF THIS THREAT WILL BE IN THE
TONIGHT PERIOD AFTER 00Z. FOR THIS MORNINGS FORECAST UPDATE HAVE
INCLUDED HIGH EARLY MORNING POPS FOR THE PREVIOUSLY DISCUSSED BANDS
OF STORMS CURRENTLY ON RADAR...BUT THEN PULLED BACK SIGNIFICANTLY ON
POPS IN THE EARLY AND MID AFTERNOON HOURS BEFORE INCREASING THEM
AGAIN RIGHT BEFORE 00Z. ALL OTHER FORECAST FIELDS WILL ALSO BE
AFFECTED BY THE MORNING CONVECTION AND THE NORTHWARD MOVEMENT OF THE
WARM FRONT...AND ESTF UPDATES WILL BE PARTICULARLY IMPORTANT
THROUGHOUT THE DAY.

.LONG TERM /TONIGHT THROUGH TUESDAY/...
ISSUED AT 421 AM CDT WED JUN 24 2015

ELEVATED CONVECTIVE TRENDS AND ASSOCIATED CLOUD DEBRIS THROUGH THE
DAY WILL HAVE A BIG INFLUENCE ON SEVERE WEATHER POTENTIAL BY THIS
EVENING. AS ALLUDED TO IN THE SHORT TERM DISCUSSION...THE CAPPING
LAYER WILL INHIBIT SFC BASED CONVECTION THROUGH MUCH OF THE
AFTERNOON. AN APPROACHING SHORT WAVE AND ASSOCIATED COOLING WILL
HELP ERODE THE CAP BUT THE EROSION WILL ALSO BE CONTINGENT ON
SUFFICIENT SFC HEATING THIS AFTERNOON. SHORT TERM GUIDANCE CONTINUES
TO SUGGEST THE SFC WARM FRONT WILL BE IN THE VICINITY OF THE
INTERSTATE 80 AND HIGHWAY 30 CORRIDORS BY EARLY THIS EVENING AND
THIS WILL BE THE REGION TO WATCH FOR VIGOROUS THUNDERSTORM
DEVELOPMENT SHOULD THE CAP ERODE. EFFECTIVE DEEP LAYER SHEAR DURING
THIS PERIOD OF 40 PLUS KTS WILL BE SUPPORTIVE OF SUPERCELL
DEVELOPMENT. ALL FORMS OF SEVERE WEATHER WILL BE POSSIBLE WITH ANY
INITIAL SUPERCELLS THAT DEVELOP. LOW LEVEL SRH VALUES IN EXCESS OF
200 M2/S2 SUFFICIENT FOR TORNADOES AND CAN NOT DISCOUNT THE
POSSIBILITY OF A STRONG TORNADO CONSIDERING THE GOOD SHEAR IN THE
LOWER PORTION OF THE SOUNDINGS. SHOULD HAVE BREEZY SOUTHEAST WINDS
AHEAD OF THE STORMS FURTHER ENHANCING THE LOW LEVEL SHEAR. VERY
LARGE HAIL WILL ALSO BE POSSIBLE WITH THESE STORMS IN ADDITION TO
DAMAGING WINDS. THESE STORMS WILL GRADUAL EVOLVE INTO A MORE
LINEAR SYSTEM THROUGH THE EVENING WITH DAMAGING WINDS THE PRIMARY
THREAT THOUGH 0-3 KM LINE NORMAL SHEAR VALUES APPROACHING 50KTS
WILL SUPPORT MESOVORTEX DEVELOPMENT AND AN ATTENDANT TORNADO
THREAT. VERY HEAVY RAIN IS ALSO A CONCERN. BUNKERS RIGHT SUPERCELL
MOTIONS OF 10 TO 15 KTS WITH PWAT VALUES NEARING 2 INCHES COULD
LEAD TO A SIGNIFICANT AMOUNT OF RAIN OVER A SHORT PERIOD OF TIME.
HAVE EXPANDED THE FLASH FLOOD WATCH TO THE NORTH AND WEST DUE TO
RAINFALL POTENTIAL AND WHAT HAS OCCURRED ALREADY THIS MORNING.
FARTHER NORTH...ELEVATED SEVERE STORMS ARE POSSIBLE ALONG WITH
LOCALLY HEAVY RAINFALL.

THURSDAY WILL GENERALLY BE A TRANSITION DAY WITH LOW POPS POSSIBLY
MAINLY FAR SOUTH. A SHORT WAVE WILL PASS THROUGH THURSDAY NIGHT INTO
FRIDAY AND IN COMBINATION TO AN INTENSIFYING UPPER HIGH OVER THE
WESTERN CONUS...WILL LEAD TO COOLER WEATHER FRIDAY AND INTO THE
WEEKEND. THIS FLOW IS EXPECTED TO PERSIST THROUGH EARLY NEXT WEEK.
PLEASANT CONDITIONS AND PERIODIC CHANCES FOR PRECIPITATION EXIST
THROUGH THIS PERIOD.

&&

.AVIATION...24/12Z
ISSUED AT 628 AM CDT WED JUN 24 2015

GENERALLY VFR CONDITIONS WILL PREVAIL TODAY...EXCEPT IN AND NEAR
THUNDERSTORMS WHICH MAY BECOME NUMEROUS AT TIMES. THESE STORMS
WILL BE CONFINED TO THE SOUTHERN TERMINALS THIS MORNING...BUT FROM
LATE AFTERNOON INTO EARLY TONIGHT THERE IS CONSIDERABLE
UNCERTAINTY AS TO WHERE ADDITIONAL STORMS WILL DEVELOP SO HAVE
INCLUDED VCTS AT ALL TERMINALS FOR NOW AND WILL REFINE DETAILS AT
THE 18Z ISSUANCE. LATER TONIGHT...AFTER THE STORMS HAVE
ENDED...FORECAST SOUNDINGS AND THE SYNOPTIC PATTERN LEAD TO THE
LIKELIHOOD OF MVFR STRATUS/BR DEVELOPING AND HAVE ALSO TRENDED
THAT WAY AT THE END OF THE 12Z TAFS.

&&

.HYDROLOGY...
ISSUED AT 421 AM CDT WED JUN 24 2015

HAVE EXPANDED THE FLASH FLOOD WATCH TO THE NORTH AND WEST DUE TO
LOCALLY HEAVY RAINFALL OCCURRING EARLY THIS MORNING AND SATURATING
THE GROUND...RECENT HEAVY RAINFALL AND THE POTENTIAL FOR
SIGNIFICANT RAINFALL ALONG THE WARM FRONT WITH ANY STORMS THAT
DEVELOP. SUPERCELL MOTIONS ARE QUITE SLOW AT 10 TO 15 KTS AND
RIGHT MOVER MOTIONS ARE NEARLY PARALLEL TO THE WARM FRONT WHICH
COULD LEAD TO THE TRAINING OF STORMS. RAINFALL AMOUNTS OF 1 TO 3
INCHES ARE LIKELY THOUGH AN AREA OF 3 TO 5 INCHES IS POSSIBLE.

&&

.DMX WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH FROM 4 PM CDT THIS AFTERNOON THROUGH THURSDAY
MORNING FOR APPANOOSE-BLACK HAWK-BOONE-BREMER-BUTLER-CALHOUN-
CLARKE-DALLAS-DAVIS-FRANKLIN-GREENE-GRUNDY-GUTHRIE-HAMILTON-
HARDIN-HUMBOLDT-JASPER-LUCAS-MADISON-MAHASKA-MARION-MARSHALL-
MONROE-POLK-POWESHIEK-STORY-TAMA-WAPELLO-WARREN-WEBSTER-WRIGHT.

&&

SHORT TERM...LEE
LONG TERM...DONAVON
AVIATION...LEE
HYDROLOGY...DONAVON

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE DES MOINES IA
512 AM CDT WED JUN 24 2015

IAZ024>028-034>039-046>050-058>062-072>075-083>086-096-097-251015-
HUMBOLDT-WRIGHT-FRANKLIN-BUTLER-BREMER-CALHOUN-WEBSTER-HAMILTON-
HARDIN-GRUNDY-BLACK HAWK-GREENE-BOONE-STORY-MARSHALL-TAMA-GUTHRIE-
DALLAS-POLK-JASPER-POWESHIEK-MADISON-WARREN-MARION-MAHASKA-CLARKE-
LUCAS-MONROE-WAPELLO-APPANOOSE-DAVIS-
512 AM CDT WED JUN 24 2015

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL IOWA.

.DAY ONE...TODAY AND TONIGHT

ISOLATED SEVERE STORMS ARE POSSIBLE THIS MORNING WITH QUARTER
SIZED HAIL POSSIBLE. SEVERAL SEVERE STORMS ARE EXPECTED LATE THIS
AFTERNOON AND INTO THE EVENING. A FEW TORNADOES ARE POSSIBLE WITH
THE POTENTIAL FOR A STRONG TORNADO TO OCCUR. VERY LARGE HAIL IN
EXCESS OF 2 INCHES IN DIAMETER AND DAMAGING WINDS IN EXCESS OF 65
MPH ARE POSSIBLE. VERY HEAVY RAIN MAY ALSO OCCUR.

A FLASH FLOOD WATCH IS IN EFFECT FOR THE AREA. PLEASE REFER TO
THE NATIONAL WEATHER SERVICE WEBSITE AT WEATHER.GOV/DESMOINES FOR
FURTHER DETAILS.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

PERIODIC THUNDERSTORMS ARE POSSIBLE LATE THURSDAY THROUGH MONDAY.
AT THIS TIME...THE SEVERE WEATHER THREAT IS LOW.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS POSSIBLE TODAY ESPECIALLY BETWEEN 4 PM AND
10 PM.

IAZ004>007-015>017-023-251015-
EMMET-KOSSUTH-WINNEBAGO-WORTH-PALO ALTO-HANCOCK-CERRO GORDO-
POCAHONTAS-
512 AM CDT WED JUN 24 2015

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTH CENTRAL
IOWA.

.DAY ONE...TODAY AND TONIGHT

A FEW SEVERE STORMS ARE POSSIBLE THROUGH THIS EVENING. THE PRIMARY
THREAT IS LARGE HAIL UP TO 1.5 INCHES IN DIAMETER. AN ISOLATED
TORNADO IS MAY OCCUR. LOCALLY HEAVY RAINFALL IS ALSO POSSIBLE.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

PERIODIC THUNDERSTORMS ARE POSSIBLE LATE THURSDAY THROUGH MONDAY.
AT THIS TIME...THE SEVERE WEATHER THREAT IS LOW.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS POSSIBLE TODAY ESPECIALLY BETWEEN 3 PM AND
9 PM.

IAZ033-044-045-057-070-071-081-082-092>095-251015-
SAC-CRAWFORD-CARROLL-AUDUBON-CASS-ADAIR-ADAMS-UNION-TAYLOR-
RINGGOLD-DECATUR-WAYNE-
512 AM CDT WED JUN 24 2015

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

.DAY ONE...TODAY AND TONIGHT

A FEW SEVERE STORMS ARE POSSIBLE THROUGH THIS EVENING. THE PRIMARY
THREAT IS LARGE HAIL UP TO 1.5 INCHES IN DIAMETER AND DAMAGING
WIND GUSTS TO 60 MPH. AN ISOLATED TORNADO IS MAY OCCUR. LOCALLY
HEAVY RAINFALL IS ALSO POSSIBLE.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

PERIODIC THUNDERSTORMS ARE POSSIBLE LATE THURSDAY THROUGH MONDAY.
AT THIS TIME...THE SEVERE WEATHER THREAT IS LOW.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS POSSIBLE BETWEEN 4 PM AND 10 PM.

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
1148 AM CDT WED JUN 24 2015

IAZ046>048-059>061-241800-
JASPER IA-BOONE IA-STORY IA-DALLAS IA-POLK IA-GREENE IA-
1148 AM CDT WED JUN 24 2015

...THUNDERSTORMS WITH BRIEF HEAVY RAINFALL MOVING ACROSS THE AREA...

AT 1144 AM CDT...DOPPLER RADAR WAS TRACKING AN AREA OF THUNDERSTORMS
4 MILES NORTHEAST OF PERRY...MOVING EAST AT 45 MPH.

WINDS IN EXCESS OF 30 MPH WILL BE POSSIBLE WITH THIS STORM.

RAINFALL AMOUNTS UP TO ONE INCH WILL BE POSSIBLE WITH THIS STORM
WITH BRIEF HEAVY RAINFALL UP TO ONE HALF INCH IN 15 MINUTES. THE
STORMS WILL AFFECT URBAN AREAS AS WELL AS INTERSTATE 35 BETWEEN
DES MOINES AND GILBERT THROUGH 1 PM CDT THIS WEDNESDAY AFTERNOON.

LOCATIONS IMPACTED INCLUDE...
AMES...ANKENY...JOHNSTON...BOONE...GRIMES...PERRY...NEVADA...
BONDURANT...POLK CITY...HUXLEY...SAYLORVILLE...MADRID...OGDEN...
DALLAS CENTER...SLATER...GRANGER...GILBERT...WOODWARD...IOWA STATE
CENTER AND BOONE SPEEDWAY.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TORRENTIAL RAINFALL IS ALSO OCCURRING WITH THIS STORM...AND MAY LEAD
TO PONDING OF WATER AND DIFFICULT DRIVING. DO NOT DRIVE YOUR VEHICLE
THROUGH FLOODED ROADWAYS.

&&

LAT...LON 4172 9323 4165 9425 4205 9427 4215 9323
TIME...MOT...LOC 1644Z 263DEG 38KT 4189 9403

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SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
1229 PM CDT WED JUN 24 2015

IAZ033-034-044-045-057-241830-
AUDUBON IA-CARROLL IA-CRAWFORD IA-SAC IA-CALHOUN IA-
1229 PM CDT WED JUN 24 2015

...STRONG THUNDERSTORMS MOVING INTO THE AREA...

AT 1227 PM CDT...DOPPLER RADAR WAS TRACKING A STRONG THUNDERSTORM 6
MILES SOUTH OF DANBURY...OR 20 MILES SOUTHWEST OF IDA GROVE...MOVING
EAST AT 50 MPH.

HALF INCH HAIL AND WIND GUSTS UP TO 50 MPH WILL BE POSSIBLE WITH
THIS STORM. RAINFALL AMOUNTS UP TO ONE INCH WILL BE POSSIBLE WITH
THIS STORM.  THE STORMS MAY INTENSIFY AS THEY MOVE ACROSS THE AREA
EARLY THIS AFTERNOON.  BE PREPARED FOR SEVERE WEATHER AND TAKE
SHELTER IF NECESSARY.

LOCATIONS IMPACTED INCLUDE...
CARROLL...DENISON...SAC CITY...ROCKWELL CITY...LAKE CITY...MANNING...
COON RAPIDS...GLIDDEN...LAKE VIEW...ODEBOLT...SOUTH TWIN LAKE...BLACK
HAWK LAKE...SCHLESWIG...WALL LAKE...MANILLA...SCHALLER...POMEROY...
EARLY...DOW CITY AND CHARTER OAK.

LAT...LON 4221 9567 4221 9532 4247 9532 4248 9539
      4255 9539 4256 9465 4186 9463 4185 9509
      4186 9512 4187 9567
TIME...MOT...LOC 1727Z 262DEG 42KT 4214 9576

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