Alert archive / Iowa / Flash Flood Warnings in 2007

Flash Flood Warning 43, NWS Des Moines, IA

August 7, 2007Cass County, Iowa

NWS Des Moines, IA issued this flash flood warning at Aug 7, 2007, 12:07 AM CDT for Cass County, Iowa. It was in force for 3 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Aug 7, 2007, 12:07 AM CDT (05:07 UTC)
Expired: Aug 7, 2007, 3:00 AM CDT
In force: 3 hr
Issued by: NWS Des Moines, IA
Area: Whole counties

County Cass County, IA

The nearest sounding before it

Omaha, NE (KOAX), launched 00:00Z, 5.1 hours before the alert went out and 120 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 2407 J/kg
Mixed-layer CIN: -43 J/kg
Mixed-layer LCL: 1157 m above ground
0-6 km bulk shear: 34 kt
0-1 km storm-relative helicity: 114 m²/s²
0-3 km storm-relative helicity: 362 m²/s²
Significant tornado parameter: 2.8
Supercell composite: 22.6

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
WGUS53 KDMX 070509
FFWDMX
IAC029-070800-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
1207 AM CDT TUE AUG 7 2007

THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  CASS COUNTY IN SOUTHWEST IOWA...

* UNTIL 300 AM CDT

* AT 1204 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED 
THUNDERSTORMS MOVING OUT OF NEBRASKA THAT WILL BE MOVING OVER AREAS 
ALREADY HAVING HAD FLASH FLOODING FROM THUNDERSTORMS AND PRODUCE 
ADDTIONAL FLASH FLOODING OVER THE WARNED AREA.

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO ATLANTIC

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL
CREEKS AND STREAMS...HIGHWAYS AND UNDERPASSES. ADDITIONALLY...COUNTRY
ROADS AND FARMLANDS ALONG THE BANKS OF CREEKS...STREAMS AND OTHER LOW
LYING AREAS ARE SUBJECT TO FLOODING.

LAT...LON 4148 9513 4147 9476 4121 9475 4122 9514
TIME...MOT...LOC 0507Z 180DEG 0KT 4133 9493

$$

2 follow-up statements

000 
WGUS73 KDMX 070639
FFSDMX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
138 AM CDT TUE AUG 7 2007

IAC029-070800-
CASS IA-
138 AM CDT TUE AUG 7 2007

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 300 AM CDT FOR CASS 
COUNTY...

AT 137 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO 
INDICATE ADDITIONAL THUNDERSTORMS MOVING TOWARD THE COUNTY FROM 
NEBRASKA CAPABLE OF PRODUCING FLASH FLOODING OVER THE WARNED AREA.

LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO ATLANTIC

BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE
DANGERS OF FLOODING. IF FLASH FLOODING IS OBSERVED ACT QUICKLY. MOVE
UP TO HIGHER GROUND TO ESCAPE FLOOD WATERS. DO NOT STAY IN AREAS
SUBJECT TO FLOODING WHEN WATER BEGINS RISING.

LAT...LON 4148 9513 4147 9476 4121 9475 4122 9514
TIME...MOT...LOC 0638Z 180DEG 0KT 4133 9493

$$

000 
WGUS73 KDMX 070712
FFSDMX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
211 AM CDT TUE AUG 7 2007

IAC029-070721-
CASS IA-
211 AM CDT TUE AUG 7 2007

...THE FLASH FLOOD WARNING HAS BEEN CANCELLED FOR CASS COUNTY...

THUNDERSTORMS THAT PRODUCED HEAVY RAINS AND FLASH FLOODING IN THE 
COUNTY HAVE MOVED EAST OUT OF THE COUNTY.  STORMS IN NEBRASKA MAY 
TRACK INTO THE COUNTY AFTER 4 AM WITH ADDITIONAL HEAVY RAINS.

LAT...LON 4148 9513 4147 9476 4121 9475 4122 9514
TIME...MOT...LOC 0711Z 180DEG 0KT 4133 9493

$$

FORSTER

What forecasters said that day

The local office's own words before this flash flood warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Des Moines, IA wrote its last area forecast discussion before this flash flood warning went out at Aug 7, 12:03 AM CDT, 4 minutes earlier.

Area forecast discussion, Aug 7, 12:03 AM CDT, 4 minutes before

AREA FORECAST DISCUSSION...UPDATED FOR AVIATION
NATIONAL WEATHER SERVICE DES MOINES IA
1203 AM CDT TUE AUG 7 2007

.DISCUSSION...
ACTIVE PATTERN WL CONT THRU THE NEXT 48 HRS OR SO AS IA REMAINS IN
THE RING OF FIRE.  MCV MOVG THRU NERN NEBRASKA EVIDENT ON SAT PIX
THIS AFTN WL DRFT EWD SLOWLY OVR NGT INTO WED MRNG.  EXPECT DVLPMT
OVR NIGHT WITH THAT FEATURE.  MOISTURE TRANSPORT INTO THE AREA WED
AFTN INTO THE OVR NGT HOURS WL CONTINUE THE CHANCE INTO WED NGT.
EXPECT UPR HIGH TO BUILD FARTHER NWD AND PUSH THE ACTIVTY NORTH OF
IA BY THU AFTN INTO THE FIRST OF NXT WK.  AFTER DEALING WITH THE
PCPN CHCS OVR THE NXT 48 HRS, WX WILL BE QUITE WITH THE DOG DAYS OF
SUMMER CONTINUING.  HIGHS IN THE UPPER 80S AND 90S WITH LOWS IN THE
LOW TO MID 70S.  ATTM FEEL THAT THE HEAT INDX WILL REMAIN BLO
CRITERIA BY A FEW DEGREES THRU FCST PD.

&&

.AVIATION...08/00Z

HEAVY RAINFALL HAS SHIFTED FARTHER SOUTH ACROSS THE EXTREME SOUTHERN
TIER OF COUNTIES IN IA. AS CLEARING OVER NORTHERN IOWA HAS LED TO
PERIODS OF IFR FOG ALREADY HAVE PLACED IFR VSBYS OVERNIGHT AS DO NOT
EXPECT CONDITIONS TO IMPROVE FOR THE NEAR TERM. OTTUMWA WILL SEE
VCTS AFT 08Z THROUGH AT LEAST 10Z AND CONVECTION SHIFTS SOUTHEAST.
BY LATE MORNING TUESDAY NEXT WAVE FROM PLAINS HAS A GOOD CHANCE OF
MORE CONVECTION OVER THE AREA AND HAVE PLACE PROB30S OR TEMPOS IN
MOST OF THE TERMNALS.

&&

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

&&

AVIATION...RUSSELL

Hazardous weather outlook, Aug 6, 12:04 PM CDT, 12 hours 3 minutes before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE DES MOINES IA
1204 PM CDT MON AUG 6 2007

IAZ023>028-033>039-044>050-057>062-070>075-081>086-092>097-071715-
POCAHONTAS-HUMBOLDT-WRIGHT-FRANKLIN-BUTLER-BREMER-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-
1204 PM CDT MON AUG 6 2007

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

.DAY ONE...THIS AFTERNOON AND TONIGHT

EXPECT THUNDERSTORMS TO DEVELOP OVER MUCH OF CENTRAL IOWA THIS
AFTERNOON WITH A FEW SEVERE STORMS POSSIBLE. DAMAGING WINDS TO 65
MPH WITH BE THE PRIMARY THREAT HOWEVER NICKEL SIZED HAIL AND AN
ISOLATED TORNADO ARE ALSO POSSIBLE. CHANCES WILL CONTINUE TONIGHT.
SOME OF THESE STORMS WILL LIKELY PRODUCE TORRENTIAL AND
POTENTIALLY FLOODING RAINS. AMOUNTS OF ONE TO THREE INCHES ARE
POSSIBLE...AND EVEN HIGHER LOCALLY. THERE IS ALSO A SLIGHT RISK OF
SEVERE WEATHER WITH THE PRIMARY THREAT DAMAGING WINDS.

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

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY

CONDITIONS ARE NOT EXPECTED TO CHANGE MUCH UNTIL POSSIBLY THURSDAY
WITH MAINLY LATE AFTERNOON AND NIGHTTIME THUNDERSTORM CHANCES
STAYING IN THE FORECAST. WITH TROPICAL CONDITIONS STILL IN PLACE...ANY
STORMS THAT DO FORM WILL BE CAPABLE OF PRODUCING VERY HEAVY RAINS
AND FLOODING. SOME LOCATIONS MAY TOTAL FIVE DAY RAINFALL AMOUNTS
FROM FOUR TO EIGHT INCHES BY WEDNESDAY NIGHT. A FEW STORMS MAY
ALSO BE SEVERE WITH DAMAGING WINDS STILL THE PRIMARY THREAT.

.SPOTTER INFORMATION STATEMENT...

REPORTS OF HEAVY RAINS AND FLOODING WILL BE ESPECIALLY BENEFICIAL
THROUGH AT LEAST MIDWEEK. SPOTTER ACTIVATION FOR SEVERE WEATHER
MAY ALSO BE NEEDED A FEW TIMES.

IAZ004>007-015>017-071715-
EMMET-KOSSUTH-WINNEBAGO-WORTH-PALO ALTO-HANCOCK-CERRO GORDO-
1204 PM CDT MON AUG 6 2007

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

.DAY ONE...THIS AFTERNOON AND TONIGHT

THERE WILL BE RATHER LOW CHANCES FOR THUNDERSTORMS OVER ALL BUT
NORTHERN IOWA TODAY. HOWEVER CHANCES WILL INCREASE GREATLY LATER
TONIGHT. SOME OF THESE STORMS WILL LIKELY PRODUCE TORRENTIAL AND
POTENTIALLY FLOODING RAINS. AMOUNTS OF ONE TO THREE INCHES ARE
POSSIBLE...AND EVEN HIGHER LOCALLY. THERE IS ALSO A SLIGHT RISK OF
SEVERE WEATHER WITH THE PRIMARY THREAT DAMAGING WINDS.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY

CONDITIONS ARE NOT EXPECTED TO CHANGE MUCH UNTIL POSSIBLY THURSDAY
WITH MAINLY LATE AFTERNOON AND NIGHTTIME THUNDERSTORM CHANCES
STAYING IN THE FORECAST. WITH TROPICAL CONDITIONS STILL IN PLACE...ANY
STORMS THAT DO FORM WILL BE CAPABLE OF PRODUCING VERY HEAVY RAINS
AND FLOODING. SOME LOCATIONS MAY TOTAL FIVE DAY RAINFALL AMOUNTS
FROM FOUR TO EIGHT INCHES BY WEDNESDAY NIGHT. A FEW STORMS MAY
ALSO BE SEVERE WITH DAMAGING WINDS STILL THE PRIMARY THREAT.

.SPOTTER INFORMATION STATEMENT...

REPORTS OF HEAVY RAINS AND FLOODING WILL BE ESPECIALLY BENEFICIAL
THROUGH AT LEAST MIDWEEK. SPOTTER ACTIVATION FOR SEVERE WEATHER
MAY ALSO BE NEEDED A FEW TIMES.

In the hours before

Local storm report, Aug 6, 8:49 PM CDT, 3 hours 18 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
849 PM CDT MON AUG 06 2007

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

0845 PM     TSTM WND GST     1 NW GRISWOLD           41.25N 95.16W
08/06/2007  E60 MPH          CASS               IA   TRAINED SPOTTER

&&

BF

Local storm report, Aug 6, 9:00 PM CDT, 3 hours 7 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
900 PM CDT MON AUG 06 2007

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

0857 PM     TSTM WND DMG     3 NNE GRISWOLD          41.27N 95.12W
08/06/2007                   CASS               IA   STORM CHASER

            SIGNIFICANT SIZED TREE DOWN OVER ROAD AT 560TH AND M56.

&&

RVACHALE

Local storm report, Aug 6, 10:21 PM CDT, 1 hour 46 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
1021 PM CDT MON AUG 06 2007

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

0915 PM     FLASH FLOOD      GRISWOLD                41.23N 95.14W
08/06/2007                   CASS               IA   LAW ENFORCEMENT

            FOUR FEET OF WATER IN THE AREA WITH WATER RUNNING OVER
            HIGHWAYS

&&

GFORSTER

Local storm report, Aug 6, 10:58 PM CDT, 1 hour 9 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
1058 PM CDT MON AUG 06 2007

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

0850 PM     TSTM WND DMG     GRISWOLD                41.23N 95.14W
08/06/2007                   CASS               IA   TRAINED SPOTTER

            TREE BLOCKING ROAD AND POWER LINES DOWN.

&&

RVACHALE

Local storm report, Aug 6, 11:33 PM CDT, 34 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
1133 PM CDT MON AUG 06 2007

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

1115 PM     FLASH FLOOD      2 SE KIMBALLTON         41.61N 95.05W
08/06/2007                   AUDUBON            IA   LAW ENFORCEMENT

            WATER RUNNING OVER HIGHWAY 173

&&

GFORSTER

The office that day

Everything else NWS Des Moines, IA issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 6, 7:12 PM CDT	Severe Thunderstorm Warning	DMX	Crawford	33 min
Aug 6, 8:25 PM CDT	Severe Thunderstorm Warning	DMX	Cass	65 min
Aug 6, 8:35 PM CDT	Tornado Warning	DMX	Cass	25 min
Aug 6, 8:57 PM CDT	Tornado Warning	DMX	Cass	33 min
Aug 6, 9:08 PM CDT	Flash Flood Warning	DMX	Cass	3 hr
Aug 6, 9:17 PM CDT	Severe Thunderstorm Warning	DMX	Adams	58 min
Aug 6, 9:28 PM CDT	Flash Flood Warning	DMX	Audubon	3 hr
Aug 6, 9:31 PM CDT	Severe Thunderstorm Warning	DMX	Cass	44 min
Aug 6, 9:59 PM CDT	Flash Flood Warning	DMX	Guthrie	3 hr
Aug 6, 10:00 PM CDT	Severe Thunderstorm Warning	DMX	Adair	41 min
Aug 6, 10:36 PM CDT	Severe Thunderstorm Warning	DMX	Hamilton	39 min
Aug 6, 10:47 PM CDT	Severe Thunderstorm Warning	DMX	Audubon, Cass	43 min
Aug 6, 10:53 PM CDT	Flash Flood Warning	DMX	Carroll	3 hr
Aug 6, 11:02 PM CDT	Flash Flood Warning	DMX	Grundy, Hardin	3 hr
Aug 6, 11:22 PM CDT	Severe Thunderstorm Warning	DMX	Hardin	38 min
Aug 6, 11:37 PM CDT	Flash Flood Warning	DMX	Crawford	4 hr
Aug 7, 12:10 AM CDT	Flash Flood Warning	DMX	Audubon	3 hr
Aug 7, 12:22 AM CDT	Flash Flood Warning	DMX	Black Hawk	3 hr
Aug 7, 12:55 AM CDT	Flash Flood Warning	DMX	Guthrie	3 hr
Aug 7, 5:14 PM CDT	Severe Thunderstorm Warning	DMX	Lucas	61 min
Aug 7, 5:18 PM CDT	Severe Thunderstorm Warning	DMX	Wayne	42 min
Aug 7, 5:52 PM CDT	Severe Thunderstorm Warning	DMX	Appanoose, Monroe	38 min
Aug 7, 5:58 PM CDT	Severe Thunderstorm Warning	DMX	Wayne	47 min
Aug 7, 6:01 PM CDT	Severe Thunderstorm Warning	DMX	Taylor	44 min
Aug 7, 6:20 PM CDT	Severe Thunderstorm Warning	DMX	Decatur	40 min
Aug 7, 6:50 PM CDT	Severe Thunderstorm Warning	DMX	Union	40 min
Aug 7, 6:58 PM CDT	Severe Thunderstorm Warning	DMX	Decatur	47 min

Nearby

Flash Flood Warnings in Iowa, 2007 Every flash flood warning in 2007

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive.