Storm Events Database

Event Details

Event Hail
Magnitude 1.50 in.
State IOWA
County/Area PALO ALTO
Report Source Trained Spotter
NCDC Data Source CSV
Begin Date 2011-09-02 03:31:00.0 CST-6
Begin Location 1SSE MALLARD
Begin Lat/Lon 42.91/-94.67
End Date 2011-09-02 03:31:00.0 CST-6
End Location 1SSE MALLARD
End Lat/Lon 42.91/-94.67
Deaths Direct/Indirect 0/0 (fatality details below, when available...)
Injuries Direct/Indirect 0/0
Property Damage 2.00K
Crop Damage 10.00K
Episode Narrative A cold front entered northwest Iowa during the early morning hours of the 2nd. The airmass was relatively unstable with CAPE in the 2000 to 3000 J/kg range and lifted indices of -5 to -8 C. A considerable amount of downdraft CAPE was available with values ranging from 1100 to 1500 J/kg. The atmosphere was moderately sheared with 30 to 45 kts of shear available. CAPE in the -10 to -30 C layer of the atmosphere was between 400 and 800 J/kg, however the freezing level of 16,500 feet limited hail growth in many of the storms. Precipitable water values were around 1.8 inches as a low level jet of 40 to 50 kts drew moisture northeast into the state. A large supercell developed over northwest Iowa. The storm tracked east across the northwest into the north central counties. It produced hail of 1.5 inches in diameter in Palo Alto County, and 61 MPH winds in Hancock County. As the storms moved into Worth County, strong winds downed tree branches and power lines with winds of around 60 MPH reported. There were numerous reports of 40 to 50 mph winds and pea to dime size hail along its track. The storm produced very strong winds east of Northwood in Worth County. High winds flattened corn crops and also bent the propeller tip of a wind generator.
Event Narrative Trained spotter reports quarter to ping pong ball size hail.


All events for this episode:

Location County/Zone St. Date Time T.Z. Type Mag Dth Inj PrD CrD
Totals: 0 0 266.00K 150.00K
CURLEW PALO ALTO CO. IA 09/02/2011 03:25 CST-6 Hail 0.88 in. 0 0 0.00K 5.00K
MALLARD PALO ALTO CO. IA 09/02/2011 03:31 CST-6 Hail 1.50 in. 0 0 2.00K 10.00K
FOREST CITY WINNEBAGO CO. IA 09/02/2011 04:24 CST-6 Thunderstorm Wind 52 kts. EG 0 0 5.00K 0.00K
MILLER HANCOCK CO. IA 09/02/2011 04:25 CST-6 Thunderstorm Wind 53 kts. MG 0 0 1.00K 0.00K
DEER CREEK WORTH CO. IA 09/02/2011 04:44 CST-6 Thunderstorm Wind 52 kts. EG 0 0 3.00K 25.00K
GRAFTON WORTH CO. IA 09/02/2011 04:45 CST-6 Thunderstorm Wind 52 kts. EG 0 0 5.00K 10.00K
MELTONVILLE WORTH CO. IA 09/02/2011 04:47 CST-6 Thunderstorm Wind 70 kts. EG 0 0 250.00K 100.00K
Totals: 0 0 266.00K 150.00K