Thunderstorms erupted again across Iowa and an upper level wave interacted with a stationary boundary that remained east to west across the state. The most intense storms were over the southern part of the state with this around as they were more focused on the outflow boundary from the morning convection.
Every event with a place to put it. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS DMX wrote it up.
Thunderstorms erupted again across Iowa and an upper level wave interacted with a stationary boundary that remained east to west across the state. The most intense storms were over the southern part of the state with this around as they were more focused on the outflow boundary from the morning convection. Air to the south of the outflow boundary was quite unstable with CAPE in the 2000 to 3000 J/kg range and lifted indices around -4. Downdraft CAPE was in excess of 1000 J/kg south of the boundary as well. A line of thunderstorms formed. They were elevated in nature, but a few became severe and produced high winds. A 65 MPH wind gust occurred in Taylor County. High winds downed trees and flattened 100 acres of corn in Wayne County.
The local office's own words before the first event, 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 the first event at Aug 22, 2:17 PM CST, 3 hours earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DES MOINES IA 317 PM CDT WED AUG 22 2007 .DISCUSSION... NEXT ROUND FOR HEAVY PRECIPITATION IS WELL UNDERWAY AND IS BEGINNING TO EXPAND AS STRONG MOISTURE TRANSPORT BEGINNING TO LIFT INTO THE STATE. A STATIONARY FRONTAL BOUNDARY OVER CENTRAL IOWA WILL MOVE LITTLE OVERNIGHT AND EXPECT THUNDERSTORMS TO CONTINUE TO FIRE ALONG THE BOUNDARY TONIGHT AS THE LOW LEVEL JET INCREASES AND POINTS INTO THE STATE THIS EVENING. MANY THUNDERSTORMS TODAY HAVE BEEN DROPPING NEARLY 1 INCH OF RAIN IN 15 MINUTES. THE STORMS WILL REMAIN EFFICIENT RAIN PRODUCERS WITH DEEP WARM CLOUD DEPTH REMAINING OVER THE STATE ALONG WITH PRECIPITABLE WATER VALUES EXCEEDING 2 INCHES. RAINFALL AMOUNTS OF 2 TO 4 INCHES WILL BE COMMON WITH ISOLATED AMOUNT APPROACHING 7 INCHES. EXPECT ANOTHER COMPLEX TO LIFT NORTHEAST OUT OF KANSAS AND SOUTHERN NEBRASKA LATE TONIGHT AND MOVE ACROSS CENTRAL IOWA ON THURSDAY. ANOTHER ROUND OF VERY HEAVY RAINFALL IS LIKELY. AS WITH THE PAST FEW DAYS...EXPECT ANOTHER FLASH FLOOD WATCH TO BE ISSUED WITH THE EARLY MORNING FORECAST TO EXPAND INTO FRIDAY. CURRENT WATCH WILL FOCUS ON TONIGHT AND THURSDAY. AS MENTIONED YESTERDAY...MOISTURE FROM HURRICANE DEAN IS EXPECTED TO ARRIVE BY LATE THURSDAY INTO FRIDAY. ONE FINAL ROUND OF HEAVY RAINFALL IS LIKELY DURING THIS PERIOD BEFORE HIGH PRESSURE DROPPING SOUTH OUT OF CANADA FINALLY PUSHES EVERYTHING TO THE SOUTHEAST. HAVE CONTINUED TO KEEP SUNDAY AND SUNDAY NIGHT DRY BUT WILL MONITOR AS RETURN FLOW DEVELOPS AND MAY BRING A THREAT FOR ELEVATED THUNDERSTORMS. THE REMNANTS OF DEAN ARE STILL ON TRACK TO ARRIVE OVER THE UPPER MIDWEST BY AROUND TUESDAY AND HAVE MAINTAINED COURSE WITH THUNDERSTORMS POSSIBLE BY THIS TIME. && .AVIATION...22/18Z SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS CONTINUE ACROSS NORTH CENTRAL IOWA...WITH IFR/MVFR CLOUD BASES. HEAVY RAIN IS EXPECTED WITH REDUCED VISIBILITIES INTO THE IFR/MVFR CATEGORIES. THUNDERSTORM ACTIVITY IS EXPECTED TO INCREASE INTO THE LATE AFTERNOON AND EVENING HOURS...WITH CONDITIONS SIMILAR TO TUE NIGHT EXPECTED. ACROSS SOUTH CENTRAL IOWA...A MID-LEVEL CLOUD DECK IS EXPECTED TO DEVELOP INTO THE AFTERNOON HOURS...WITH THUNDERSTORM CHANCES FOR LATER TODAY INTO TONIGHT. && .DMX WATCHES/WARNINGS/ADVISORIES...FLASH FLOOD WATCH THROUGH 10 AM THURSDAY. IAZ004>007-IA015>017-IA023>028-IA033>039-IA044>050-IA057>060 && LONG TERM...DONAVON SHORT TERM/AVIATION...ALBRECHT
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE DES MOINES IA 420 PM CDT WED AUG 22 2007 IAZ004>007-015>017-023>028-033>039-044>050-057>060-232130- EMMET-KOSSUTH-WINNEBAGO-WORTH-PALO ALTO-HANCOCK-CERRO GORDO- 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- 420 PM CDT WED AUG 22 2007 ...SERIOUS FLOODING SITUATION MAY WORSEN... THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTH CENTRAL AND CENTRAL IOWA. .DAY ONE...TONIGHT WIDESPREAD TO SCATTERED THUNDERSTORMS ARE EXPECTED TO CONTINUE THROUGH THE EVENING INTO THE OVERNIGHT HOURS ACROSS CENTRAL AND NORTH CENTRAL IOWA. ADDITIONAL HEAVY RAINS LEADING TO ANOTHER ROUND OF FLASH FLOODING IS POSSIBLE TONIGHT. WIDESPREAD RAINFALL AMOUNTS OF 2 TO 4 INCHES MAY OCCUR WITH LOCALLY HIGHER AMOUNTS OF 5 OR 7 INCHES POSSIBLE. RAINFALL OF THIS MAGNITUDE WITH NEARLY TOTAL RUNOFF WOULD COMPOUND SERIOUS FLOODING SITUATIONS ALREADY IN PROGRESS IN SEVERAL LOCATIONS. A FLASH FLOOD WATCH IS IN EFFECT FOR THE AREA AS ARE SEVERAL RIVER FLOOD WARNINGS...AND FLOOD WARNINGS FOR SOME URBAN AREAS AND SMALL STREAMS. PLEASE REFER TO THE NATIONAL WEATHER SERVICE WEBSITE AT WEATHER.GOV/DESMOINES FOR ADDITIONAL DETAILS. ALTHOUGH FLOODING IS POSSIBLE IN THE ENTIRE WATCH AREA...THE LOCATIONS WITH THE GREATEST THREAT OF HEAVY RAINS AND FLOODING ARE UNFORTUNATELY IN THOSE AREAS ALREADY HARDEST HIT IN NORTHWEST IOWA FROM FORT DODGE FARTHER NORTH AND WEST. SEVERE THUNDERSTORMS ARE POSSIBLE ALONG WITH THE FLASH FLOOD POTENTIAL. LARGE HAIL...DAMAGING WINDS...AND TO A LESSER EXTENT TORNADOES MAY OCCUR WITH THE STRONGER STORMS. .DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY CHANCES FOR THUNDERSTORMS REMAIN IN THE FORECAST THROUGH LATE FRIDAY AND THEN AGAIN ON TUESDAY. SEVERE WEATHER...HEAVY RAINS AND FLOODING WILL STILL BE POSSIBLE THROUGH THE REMAINDER OF THE WORK WEEK. THE FLOODING SITUATION WILL LIKELY NOT IMPROVE UNTIL THE WEEKEND...AND MAY EVEN WORSEN UNTIL THAT TIME. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION MAY BE NEEDED THIS EVENING INTO THE NIGHTTIME HOURS...AND THEN PERIODICALLY THROUGH FRIDAY. REPORTS OF HEAVY RAINS AND FLOODING WOULD ALSO BE QUITE BENEFICIAL. IAZ061-062-070>075-081>086-092>097-232130- JASPER-POWESHIEK-CASS-ADAIR-MADISON-WARREN-MARION-MAHASKA-ADAMS- UNION-CLARKE-LUCAS-MONROE-WAPELLO-TAYLOR-RINGGOLD-DECATUR-WAYNE- APPANOOSE-DAVIS- 420 PM CDT WED AUG 22 2007 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL IOWA. .DAY ONE...TONIGHT SCATTERED THUNDERSTORMS ARE EXPECTED TO CONTINUE THROUGH THE EVENING INTO THE OVERNIGHT HOURS. LOCALLY HEAVY RAINFALL ALONG WITH ISOLATED SEVERE WEATHER IS POSSIBLE. THE MAIN THREATS ARE LARGE HAIL AND/OR DAMAGING WINDS. ALTHOUGH THE CHANCE OF A TORNADO CANNOT BE COMPLETELY RULED OUT. .DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY CHANCES FOR THUNDERSTORMS REMAIN IN THE FORECAST THROUGH LATE FRIDAY AND THEN AGAIN ON TUESDAY. SEVERE WEATHER AND HEAVY RAINS WILL STILL BE POSSIBLE THROUGH THE REMAINDER OF THE WORK WEEK. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION MAY BE NEEDED THIS EVENING...AND THEN PERIODICALLY THROUGH FRIDAY. REPORTS OF HEAVY RAINS AND FLOODING WOULD ALSO BE QUITE BENEFICIAL.
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
1259 PM CDT WED AUG 22 2007
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1015 AM TSTM WND DMG N SCHALLER 42.50N 95.30W
08/22/2007 SAC IA TRAINED SPOTTER
12 TO 18 INCH BRANCHES DOWN IN TOWN
&&
ALBRECHTPRELIMINARY LOCAL STORM REPORT...CORRECTED
NATIONAL WEATHER SERVICE DES MOINES IA
555 PM CDT WED AUG 22 2007
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0629 AM FLOOD FORT DODGE 42.51N 94.18W
08/22/2007 WEBSTER IA EMERGENCY MNGR
NOTE THERE WAS NO LEVEE BREACH ON THE DES MOINES RIVER IN
FORT DODGE.
&&
RDONAVONThe Des Moines radar (KDMX), 118 km away, was scanning. The volume nearest the first event began at 23:17 UTC.
2 thunderstorm wind. Local standard time, as filed.
High winds blew down Numerous large maple trees around a farm with 100 acres of flattened corn.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Iowa in 2007Every state in 2007This day in weather historyWarnings in Iowa, August 2007
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 42527, 42528.