Storm Events Database

Event Details

Event Flash Flood
-- Flood Cause Heavy Rain
State IOWA
County/Area SAC
WFO DMX
Begin Date 07/22/2010 07:00:00 CST-6
Begin Range 2
Begin Azimuth NE
Begin Location SCHALLER
Begin Lat/Lon 42.52/-95.28
End Date 07/22/2010 08:00:00 CST-6
End Range 3
End Azimuth WNW
End Location NEMAHA
End Lat/Lon 42.53/-95.13
Deaths Direct/Indirect 0/0 (fatality details below, when available...)
Injuries Direct/Indirect 0/0
Property Damage 100.00K
Crop Damage 0.00K
Episode Narrative A strong warm advection pattern set up over Iowa during the evening of the 21st into the morning hours of the 22nd. Strong moisture transport pooled moisture over the state with precipitable water values increasing to 2 to 2.3 inches over the north half of the state. An MCC developed over southeast South Dakota and far northeast Nebraska during the evening. The MCS was fed by 2000 to 3000 J/kg of CAPE with a relatively unstable atmosphere. Lifted indices were around -4 C. The shear environment was relatively favorable with 40 to 50 kts of effective shear over the area. Thunderstorms trained over northern Iowa and produced heavy rainfall amounts. Rainfall amounts of 3 to 5 inches were common from Hardin County, west through Sac County and into Pocahontas County. Five inches of rain fell in a 2-3 hour period just west of Fort Dodge. This resulted in flash flooding in the area. Flowing water 2 to 3 feet deep was reported in the city of Fort Dodge. Flash flooding also occurred in Sac and Calhoun Counties. Numerous roads were flooded with numerous basements flooded in Manson. During the early stage of the MCC development, severe weather occurred in Pocahontas County. A strong shear environment was observed at the time over Pocahontas County. In the city of Pocahontas, a Coop building and implement machine shed had significant damage along Highway 3 and Main Street. Several large tree branches were downed with whole trees blown down on the northeast side of town. Some of the trees were 3 feet in diameter. Damage was also reported at the country club in Pocahontas. An EF1 tornado moved through the southeast part of town as well with this storm. The tornado touched down 1 to 2 miles south of Pocahontas near Highway 4. It traveled 2.6 miles on the ground, then lifted just northeast of the golf course and prior to reaching the airport. The tornado was described as diffuse in nature. Damage included a Coop suffering partial structural collapse and the roof and ceiling lifted off the structure. At the Sale Barn, machinery and carts were carried aloft both west and northwest of the location due to the circulation of the tornado. The walls of the barn were also damaged by the tornado. Three to four foot diameter trees were also uprooted and down in the Pocahontas Cemetery. The tornado lifted off the ground at approximately 0141 CST. The wind speed was estimated to be 100 MPH.
Event Narrative Numerous roads were closed, including Hope Ave between 190th and 200th St, 170th between Ira and Jackson, Lee Ave was down to one lane between 390th and 400th.


All events for this episode:

Location County/Zone St. Date Time T.Z. Type Mag Dth Inj PrD CrD
Totals: 0 0 1.975M 10.00K
GOWRIE WEBSTER CO. IA 07/21/2010 23:00 CST-6 Heavy Rain 0 0 0.00K 0.00K
MANSON CALHOUN CO. IA 07/22/2010 00:00 CST-6 Heavy Rain 0 0 0.00K 0.00K
WEBSTER CITY ARPT HAMILTON CO. IA 07/22/2010 00:00 CST-6 Heavy Rain 0 0 0.00K 0.00K
FT DODGE WEBSTER CO. IA 07/22/2010 01:14 CST-6 Heavy Rain 0 0 0.00K 0.00K
POCAHONTAS POCAHONTAS CO. IA 07/22/2010 01:33 CST-6 Thunderstorm Wind 65 kts. EG 0 0 100.00K 0.00K
WESTVIEW POCAHONTAS CO. IA 07/22/2010 01:38 CST-6 Tornado EF1 0 0 1.000M 10.00K
FT DODGE WEBSTER CO. IA 07/22/2010 03:45 CST-6 Flash Flood 0 0 250.00K 0.00K
FT DODGE WEBSTER CO. IA 07/22/2010 04:00 CST-6 Flash Flood 0 0 250.00K 0.00K
FT DODGE WEBSTER CO. IA 07/22/2010 07:00 CST-6 Flash Flood 0 0 25.00K 0.00K
ROCKWELL CITY CALHOUN CO. IA 07/22/2010 07:00 CST-6 Flash Flood 0 0 250.00K 0.00K
SCHALLER SAC CO. IA 07/22/2010 07:00 CST-6 Flash Flood 0 0 100.00K 0.00K
Totals: 0 0 1.975M 10.00K