The first significant severe weather outbreak of the season took place during the afternoon and evening of the 14th with all modes of severe weather taking place.  An upper level low pressure lifted northeast out of the southwest U.S.  The upper level center, as well as the surface low, passed northwest of Iowa, across southeast South Dakota into Minnesota.  Severe weather developed north of the warm front as it lifted north into Iowa.  A cluster of severe storms formed over northeast Kansas and southeast Nebraska.  These storms moved east-northeast along the warm front into Iowa, causing a considerable amount of severe weather.  Severe weather parameters were fairly strong, however the dynamics of a 100 kt mid level jet and 60 kt low level jet made up the difference.  Just prior to the storm development, CAPE values were around 4000 J/kg south of the development.  Helicity was high, in the 300 to 500 range.  There was a large amount of effective shear with 50 to 65 kts available.  CAPE in the -10 to -30 layer of the atmosphere was in the 200 to 400 J/kg range, while downdraft CAPE was 600 to 800 J/kg.  Plenty of low level moisture was drawn into the state on the strong low level jet.  Precipitable water vales rose to 1.25 inches quite rapidly.  The LCL level was relatively high, but given the dynmics was relatively easy to overcome.  The LCL was just under 1000 meters at the beginning of the event.  There were three tornadoes reported during the event.  One was northwest of the Creston area in Union County.  The most significant tornado caused high end EF2 damage to the far northwest corner of Creston. This tornado formed southwest of Cromwell at 1752 CST in Adams county and quickly tracked into northwest Creston around 1800 CST. EF2 damage occurred to the Greater Regional Medical Center and the Southwestern Community College campus. The tornado continued tracking to the northeast and damaged several farmsteads northeast of Creston before dissipating about 10 miles northeast of town at approximately 1815 CST.  The wind strength was estimated to be 130 MPH. Significant damage occurred with uninsured damage alone near $2,000,000.  A tornado touched down in Warren County east of New Virginia.  The tornado caused damage to farm buildings and campers with a considerable amount of sheet metal left lying around.  The EF1 tornado produced winds around 100 MPH.  Many of the thunderstorms brought with them high winds and hail.  The final tornado touched down in Mahaska County.  The tornado was an EF1 tornado with a broad and intense rear flank downdraft south of the track.  The AWOS site at the Oskaloosa airport in Mahaska County recorded a 97 MPH wind gust from the rear flank downdraft of the storm. Reports from the Emergency Manager indicated that damage at the airport was limited to two hangar doors and some damage to airport buildings.  There were no planes on the field at the time. Numerous reports of hail larger than quarter size were received.  Some of the larger hail included baseball size hail in Clarke County at Murray and numerous reports of golf ball size hail along the track of the severe cluster from Union County to Mahaska County.  The same cluster of storms also produced very strong winds along its path.  Numerous reports of 60 to 70 MPH winds were received all along the path.  Numerous reports of tree and power line damage were received.  The Des Moines metro area was hard hit with winds of up to 65 MPH causing considerable tree damage.  At one time, 20,000 customers were reported without power.  In Marion County a garage was destroyed and a house significantly damaged by the wind east of Knoxville.   The storms also produced very heavy rainfall.  Rainfall of 2 to 4 inches was reported at several locations.  At the Des Moines International Airport, 1.10 inches of rain fell between 1630 and 1637 CST.  This amount of rainfall in that short of period of time was a 100 year event.  Fortunately it had been quite dry across the state, limiting the flash flood potential.  Flash flooding was reported in Polk, Cass, and Madison Counties.  Water was reported flowing one to two feet deep.  Numerous reports were also received of street flooding and significant ponding.

Hail in WARREN, IOWA
From 14-APR-12 17:54:00 to 14-APR-12 17:54:00 (CST-6)
Location: NEW VIRGINIA
Magnitude: 1.25 
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in CLARKE, IOWA
From 14-APR-12 17:50:00 to 14-APR-12 17:50:00 (CST-6)
Location: JAMISON
Magnitude: 1.00 
Property damage: 1.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in CLARKE, IOWA
From 14-APR-12 17:47:00 to 14-APR-12 17:47:00 (CST-6)
Location: OSCEOLA MUNI ARPT
Magnitude: 1.00 
Property damage: 1.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in UNION, IOWA
From 14-APR-12 17:57:00 to 14-APR-12 17:57:00 (CST-6)
Location: CROMWELL
Magnitude: 1.00 
Property damage: 1.00K
Crop damage: 0.00K
Reported by: Amateur Radio

Hail in UNION, IOWA
From 14-APR-12 18:20:00 to 14-APR-12 18:20:00 (CST-6)
Location: TALMAGE
Magnitude: 1.75 
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Hail in WARREN, IOWA
From 14-APR-12 18:00:00 to 14-APR-12 18:00:00 (CST-6)
Location: NEW VIRGINIA
Magnitude: 1.25 
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Public

Measured 1.2 inch diameter after a few minutes of melting.

Hail in UNION, IOWA
From 14-APR-12 18:09:00 to 14-APR-12 18:09:00 (CST-6)
Location: CRESTON
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Winds of 40 to 50 MPH with the hail.

Hail in CLARKE, IOWA
From 14-APR-12 18:29:00 to 14-APR-12 18:29:00 (CST-6)
Location: MURRAY
Magnitude: 2.75 
Property damage: 50.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in CLARKE, IOWA
From 14-APR-12 18:37:00 to 14-APR-12 18:37:00 (CST-6)
Location: OSCEOLA MUNI ARPT
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in UNION, IOWA
From 14-APR-12 17:47:00 to 14-APR-12 17:47:00 (CST-6)
Location: CRESTON
Magnitude: 1.00 
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Nickel to quarter size hail.

Hail in LUCAS, IOWA
From 14-APR-12 19:21:00 to 14-APR-12 19:21:00 (CST-6)
Location: LUCAS
Magnitude: 1.75 
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in LUCAS, IOWA
From 14-APR-12 19:29:00 to 14-APR-12 19:29:00 (CST-6)
Location: CHARITON
Magnitude: 1.00 
Property damage: 50.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Quarter size hail along with estimated 60 MPH wind gusts.

Hail in MARION, IOWA
From 14-APR-12 19:45:00 to 14-APR-12 19:45:00 (CST-6)
Location: PELLA
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Pea to dime size hail and minor street flooding.

Hail in MONROE, IOWA
From 14-APR-12 20:00:00 to 14-APR-12 20:00:00 (CST-6)
Location: AVERY
Magnitude: 2.50 
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in CLARKE, IOWA
From 14-APR-12 18:30:00 to 14-APR-12 18:30:00 (CST-6)
Location: OSCEOLA
Magnitude: 1.00 
Property damage: 3.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Dime to quarter size hail along with 1.67 inches of rain in 20 minutes.

Hail in MAHASKA, IOWA
From 14-APR-12 20:07:00 to 14-APR-12 20:07:00 (CST-6)
Location: TRUAX
Magnitude: 1.75 
Property damage: 15.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in WARREN, IOWA
From 14-APR-12 18:00:00 to 14-APR-12 18:00:00 (CST-6)
Location: ST MARYS
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Thunderstorm Wind in POLK, IOWA
From 14-APR-12 18:48:00 to 14-APR-12 19:00:00 (CST-6)
Location: WINDSOR HGTS
Magnitude: 55.00 MG
Property damage: 2.00K
Crop damage: 0.00K
Reported by: NWS Employee

Measured by NWS employee.

Thunderstorm Wind in POLK, IOWA
From 14-APR-12 18:50:00 to 14-APR-12 18:50:00 (CST-6)
Location: DES MOINES
Magnitude: 52.00 EG
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Power lines were down with four to five inches of running water in the streets.

Thunderstorm Wind in POLK, IOWA
From 14-APR-12 18:59:00 to 14-APR-12 18:59:00 (CST-6)
Location: JOHNSTON
Magnitude: 52.00 EG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Small branches broken off with minor street flooding.

Thunderstorm Wind in POLK, IOWA
From 14-APR-12 18:58:00 to 14-APR-12 18:58:00 (CST-6)
Location: DES MOINES
Magnitude: 52.00 EG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Tree limbs were blown down by high winds.

Thunderstorm Wind in JASPER, IOWA
From 14-APR-12 19:23:00 to 14-APR-12 19:23:00 (CST-6)
Location: REASNOR
Magnitude: 57.00 EG
Property damage: 50.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A steel shed was blown away by high winds.

Thunderstorm Wind in POLK, IOWA
From 14-APR-12 19:00:00 to 14-APR-12 19:00:00 (CST-6)
Location: WEST DES MOINES
Magnitude: 57.00 EG
Property damage: 100.00K
Crop damage: 0.00K
Reported by: Fire Department/Rescue

Most of the roof torn away on a commercial building.

Thunderstorm Wind in POLK, IOWA
From 14-APR-12 18:50:00 to 14-APR-12 18:50:00 (CST-6)
Location: LOVINGTON
Magnitude: 50.00 EG
Property damage: 2.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Small trees were blown over.

Thunderstorm Wind in ADAMS, IOWA
From 14-APR-12 14:13:00 to 14-APR-12 14:13:00 (CST-6)
Location: LINCOLN CENTER
Magnitude: 52.00 EG
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Storm Chaser

Cars were damaged with trees down.  A transformer was blown.  Funnel clouds were also observed.

Thunderstorm Wind in MARION, IOWA
From 14-APR-12 19:29:00 to 14-APR-12 19:29:00 (CST-6)
Location: KNOXVILLE
Magnitude: 57.00 EG
Property damage: 75.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trees were blown down along with dime size hail reported.

Hail in ADAMS, IOWA
From 14-APR-12 14:00:00 to 14-APR-12 14:05:00 (CST-6)
Location: LINCOLN CENTER
Magnitude: 1.00 
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail fell for about five minutes.

Hail in CASS, IOWA
From 14-APR-12 14:27:00 to 14-APR-12 14:27:00 (CST-6)
Location: MASSENA
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Hail in MADISON, IOWA
From 14-APR-12 15:30:00 to 14-APR-12 15:30:00 (CST-6)
Location: WINTERSET
Magnitude: 1.00 
Property damage: 1.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in MADISON, IOWA
From 14-APR-12 15:31:00 to 14-APR-12 15:31:00 (CST-6)
Location: WINTERSET
Magnitude: 1.00 
Property damage: 1.00K
Crop damage: 0.00K
Reported by: Amateur Radio

Hail in WARREN, IOWA
From 14-APR-12 16:14:00 to 14-APR-12 16:14:00 (CST-6)
Location: NORWALK
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in WARREN, IOWA
From 14-APR-12 16:21:00 to 14-APR-12 16:21:00 (CST-6)
Location: NORWALK
Magnitude: 1.00 
Property damage: 2.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in POLK, IOWA
From 14-APR-12 16:25:00 to 14-APR-12 16:25:00 (CST-6)
Location: DES MOINES
Magnitude: 1.00 
Property damage: 2.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Thunderstorm Wind in ADAIR, IOWA
From 14-APR-12 15:00:00 to 14-APR-12 15:00:00 (CST-6)
Location: GREENFIELD
Magnitude: 69.00 EG
Property damage: 100.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Damage to several trees, along with roof damage to a building.

Hail in MADISON, IOWA
From 14-APR-12 15:24:00 to 14-APR-12 15:24:00 (CST-6)
Location: MIDDLE RIVER
Magnitude: 1.00 
Property damage: 1.00K
Crop damage: 0.00K
Reported by: Law Enforcement

At Highway 92 and Pitzer Road.

Thunderstorm Wind in ADAMS, IOWA
From 14-APR-12 17:55:00 to 14-APR-12 17:55:00 (CST-6)
Location: STRINGTOWN
Magnitude: 56.00 EG
Property damage: 10.00K
Crop damage: 0.00K
Reported by: State Official

Large tree blown down and over the road near intersection of highway 49 and 34.

Hail in DALLAS, IOWA
From 14-APR-12 15:25:00 to 14-APR-12 15:25:00 (CST-6)
Location: DEXTER
Magnitude: 1.00 
Property damage: 2.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in POLK, IOWA
From 14-APR-12 16:19:00 to 14-APR-12 16:37:00 (CST-6)
Location: (DSM)DES MOINES INTL
Magnitude: 1.00 
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Report from the Des Moines International Airport that hail fell from 1619-1637 CDT with the largest being an inch in diameter.

Hail in POLK, IOWA
From 14-APR-12 16:27:00 to 14-APR-12 16:27:00 (CST-6)
Location: FT DES MOINES
Magnitude: 1.00 
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Located at Army Post Road and SE 5th ST.

Hail in POLK, IOWA
From 14-APR-12 16:30:00 to 14-APR-12 16:30:00 (CST-6)
Location: DES MOINES
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Pea to nickel size hail at the Capitol Building.

Hail in CLARKE, IOWA
From 14-APR-12 17:47:00 to 14-APR-12 17:47:00 (CST-6)
Location: MURRAY
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Mainly pea to dime size hail with some nickel hail.

Tornado in UNION, IOWA
From 14-APR-12 17:53:00 to 14-APR-12 18:19:00 (CST-6)
Location: CROMWELL
Tornado F-scale: EF2
Property damage: 5.00M
Crop damage: 0.00K
Reported by: NWS Storm Survey

This tornado continued in from Adams county.  NWS storm survey confirmed a strong EF2 tornado.  It entered Union county just southwest of Cromwell and tracked east-northeast through the far northwest portion of Creston.  The Greater Regional Medical Center and Southwest Community College sustained EF2 damage with the worst occurring to the Green Hills Education Center.  The tornado continued tracking northeast and damaged a few farmsteads northeast of Creston.

Heavy Rain in POLK, IOWA
From 14-APR-12 16:00:00 to 14-APR-12 19:15:00 (CST-6)
Location: GRIMES
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Storm total rainfall of 2.75 inches as of 1915 CST with 1.9 inches falling in 45 minutes.

Hail in MONROE, IOWA
From 14-APR-12 20:02:00 to 14-APR-12 20:02:00 (CST-6)
Location: HITEMAN
Magnitude: 1.00 
Property damage: 2.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in WAPELLO, IOWA
From 14-APR-12 20:05:00 to 14-APR-12 20:05:00 (CST-6)
Location: EDDYVILLE
Magnitude: 1.50 
Property damage: 15.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in MAHASKA, IOWA
From 14-APR-12 20:10:00 to 14-APR-12 20:10:00 (CST-6)
Location: OSKALOOSA
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Strong winds accompanied the hail.

Hail in MAHASKA, IOWA
From 14-APR-12 20:07:00 to 14-APR-12 20:07:00 (CST-6)
Location: OSKALOOSA
Magnitude: 1.00 
Property damage: 50.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Quarter size hail and winds of 60 to 70 MPH.

Hail in WAPELLO, IOWA
From 14-APR-12 20:40:00 to 14-APR-12 20:40:00 (CST-6)
Location: HIGHLAND CENTER
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Nickel size hail and heavy rain.

Tornado in ADAMS, IOWA
From 14-APR-12 17:52:00 to 14-APR-12 17:53:00 (CST-6)
Location: STRINGTOWN
Tornado F-scale: EF1
Property damage: 50.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

Tornado developed about one half mile west of the Adams/Union county line in Adams county.  The tornado did EF1 damage to a farmstead shortly after developing.  Shortly thereafter, the tornado continued into Union county.

Thunderstorm Wind in ADAMS, IOWA
From 14-APR-12 14:10:00 to 14-APR-12 14:10:00 (CST-6)
Location: MT ETNA
Magnitude: 65.00 EG
Property damage: 150.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Farm buildings were destroyed by high winds.

Thunderstorm Wind in ADAMS, IOWA
From 14-APR-12 14:25:00 to 14-APR-12 14:25:00 (CST-6)
Location: MT ETNA
Magnitude: 56.00 EG
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Large branches were blown down.

Heavy Rain in ADAIR, IOWA
From 14-APR-12 15:15:00 to 14-APR-12 15:15:00 (CST-6)
Location: ARBOR HILL
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Amateur Radio

Rainfall total of 1.4 inches from the first storm.

Heavy Rain in JASPER, IOWA
From 15-APR-12 06:00:00 to 15-APR-12 06:00:00 (CST-6)
Location: TURNER
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Rainfall of 3.50 inches in 24 hours.

Heavy Rain in MADISON, IOWA
From 15-APR-12 06:00:00 to 15-APR-12 06:00:00 (CST-6)
Location: WINTERSET
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Rainfall of 2.88 inches in 24 hours.

Thunderstorm Wind in DALLAS, IOWA
From 14-APR-12 18:44:00 to 14-APR-12 18:44:00 (CST-6)
Location: HADDEN HILL
Magnitude: 52.00 EG
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Reported north of Jordan Creek Mall.

Thunderstorm Wind in JASPER, IOWA
From 14-APR-12 19:28:00 to 14-APR-12 19:28:00 (CST-6)
Location: KILLDUFF
Magnitude: 65.00 EG
Property damage: 75.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Siding was ripped off a house.  Small hail also reported.

Heavy Rain in STORY, IOWA
From 15-APR-12 06:00:00 to 15-APR-12 06:00:00 (CST-6)
Location: AMES ARPT
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Rainfall of 2.78 inches in 24 hours.

Heavy Rain in POLK, IOWA
From 15-APR-12 06:00:00 to 15-APR-12 06:00:00 (CST-6)
Location: POLK CITY
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Rainfall of 3.18 inches in 24 hours.

Heavy Rain in CALHOUN, IOWA
From 15-APR-12 06:00:00 to 15-APR-12 06:00:00 (CST-6)
Location: ROCKWELL CITY
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Rainfall of 2.72 inches in 24 hours.

Heavy Rain in LUCAS, IOWA
From 15-APR-12 06:00:00 to 15-APR-12 06:00:00 (CST-6)
Location: CHARITON MUNI ARPT
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Rainfall of 2.17 inches in 24 hours.

Heavy Rain in CLARKE, IOWA
From 15-APR-12 06:00:00 to 15-APR-12 06:00:00 (CST-6)
Location: OSCEOLA
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Rainfall of 2.43 inches in 24 hours.

Heavy Rain in POLK, IOWA
From 15-APR-12 06:00:00 to 15-APR-12 06:00:00 (CST-6)
Location: (DSM)DES MOINES INTL
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Rainfall of 3.66 inches in 24 hours.

Heavy Rain in CASS, IOWA
From 15-APR-12 06:00:00 to 15-APR-12 06:00:00 (CST-6)
Location: MASSENA
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Rainfall of 3.28 inches in 24 hours.

Heavy Rain in CASS, IOWA
From 15-APR-12 06:00:00 to 15-APR-12 06:00:00 (CST-6)
Location: ATLANTIC ARPT
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Rainfall of 2.64 inches in 24 hours.

Heavy Rain in ADAIR, IOWA
From 15-APR-12 06:00:00 to 15-APR-12 06:00:00 (CST-6)
Location: ADAIR
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Rainfall of 2.40 inches in 24 hours.

Heavy Rain in TAMA, IOWA
From 15-APR-12 06:00:00 to 15-APR-12 06:00:00 (CST-6)
Location: TRAER MUNI ARPT
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Rainfall of 3.00 inches in 24 hours.

Heavy Rain in STORY, IOWA
From 15-APR-12 06:00:00 to 15-APR-12 06:00:00 (CST-6)
Location: MAXWELL
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Rainfall of 2.50 inches in 24 hours.

Heavy Rain in MARSHALL, IOWA
From 15-APR-12 06:00:00 to 15-APR-12 06:00:00 (CST-6)
Location: MARSHALLTOWN
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Rainfall of 2.50 inches in 24 hours.

Heavy Rain in POLK, IOWA
From 15-APR-12 06:00:00 to 15-APR-12 06:00:00 (CST-6)
Location: SWANWOOD
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Rainfall of 2.86 inches in 24 hours.

Heavy Rain in TAMA, IOWA
From 15-APR-12 06:00:00 to 15-APR-12 06:00:00 (CST-6)
Location: GARWIN
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Rainfall of 3.39 inches in 24 hours.

Heavy Rain in BOONE, IOWA
From 15-APR-12 06:00:00 to 15-APR-12 06:00:00 (CST-6)
Location: BOONE
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Rainfall of 2.05 inches in 24 hours.

Heavy Rain in GUTHRIE, IOWA
From 15-APR-12 06:00:00 to 15-APR-12 06:00:00 (CST-6)
Location: GUTHRIE CENTER
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Rainfall of 2.52 inches in 24 hours.

Thunderstorm Wind in MARION, IOWA
From 14-APR-12 19:30:00 to 14-APR-12 19:30:00 (CST-6)
Location: PERSHING
Magnitude: 69.00 EG
Property damage: 100.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Garage attached to a house was destroyed with part of the roof of the house taken off.  Debris from the house strewn east from the house about 100 yards.  Garage door faced west and looks to have failed first.

Thunderstorm Wind in POLK, IOWA
From 14-APR-12 18:53:00 to 14-APR-12 18:53:00 (CST-6)
Location: ASHAWA
Magnitude: 52.00 EG
Property damage: 20.00K
Crop damage: 0.00K
Reported by: Fire Department/Rescue

Three to eight inch tree limbs down at Valley Junction.

Hail in MONROE, IOWA
From 14-APR-12 19:55:00 to 14-APR-12 19:55:00 (CST-6)
Location: LOVILIA
Magnitude: 1.00 
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Quarter size hail partially covering the ground.

Thunderstorm Wind in MARION, IOWA
From 14-APR-12 19:35:00 to 14-APR-12 19:35:00 (CST-6)
Location: KNOXVILLE ARPT
Magnitude: 69.00 EG
Property damage: 100.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Roof blown off of a house with the garage blown down.

Tornado in MAHASKA, IOWA
From 14-APR-12 20:22:00 to 14-APR-12 20:24:00 (CST-6)
Location: WRIGHT
Tornado F-scale: EF1
Property damage: 75.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

The tornado was determined to be an EF1 with a broad and intense rear flank downdraft south of the track.  Peak wind was around 100 MPH.

Thunderstorm Wind in MAHASKA, IOWA
From 14-APR-12 20:22:00 to 14-APR-12 20:22:00 (CST-6)
Location: OSKALOOSA MUNI ARPT
Magnitude: 84.00 MG
Property damage: 200.00K
Crop damage: 0.00K
Reported by: AWOS

RFD winds measured by AWOS site at the airport.  Hangar doors and buildings damaged.

Thunderstorm Wind in DALLAS, IOWA
From 14-APR-12 18:40:00 to 14-APR-12 18:40:00 (CST-6)
Location: ORTONVILLE
Magnitude: 56.00 EG
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Amateur Radio

Twelve to thirteen inch diameter trees snapped at the base.

Hail in CLARKE, IOWA
From 14-APR-12 18:46:00 to 14-APR-12 18:46:00 (CST-6)
Location: OSCEOLA MUNI ARPT
Magnitude: 1.00 
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Along with 50 to 60 MPH southwest winds.

Thunderstorm Wind in POLK, IOWA
From 14-APR-12 18:53:00 to 14-APR-12 18:53:00 (CST-6)
Location: CAPITOL HGTS
Magnitude: 52.00 EG
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Ten inch diameter limbs were down along east 18th street.

Tornado in WARREN, IOWA
From 14-APR-12 18:54:00 to 14-APR-12 18:56:00 (CST-6)
Location: MEDORA
Tornado F-scale: EF1
Property damage: 200.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

Brief EF1 tornado confirmed by NWS damage survey.  The tornado touched down three miles east of New Virginia and tracked about a mile to the east-northeast before dissipating.  The tornado severely damaged several farm outbuildings and flipped several camper trailers.  Wind speeds were estimated around 100 MPH.

Thunderstorm Wind in POLK, IOWA
From 14-APR-12 19:02:00 to 14-APR-12 19:02:00 (CST-6)
Location: DES MOINES
Magnitude: 57.00 EG
Property damage: 100.00K
Crop damage: 0.00K
Reported by: Public

Large trees down near 18th and Woodland in the Sherman Hoyt area.  Significant tree damage.

Flash Flood in MADISON, IOWA
From 14-APR-12 19:07:00 to 14-APR-12 19:45:00 (CST-6)
Location: WINTERSET
Flood cause: Heavy Rain
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Widespread flash flooding in Madison County.  Some roads under water, especially west, south, and north of Winterset.

Flash Flood in POLK, IOWA
From 14-APR-12 19:15:00 to 14-APR-12 21:30:00 (CST-6)
Location: SWANWOOD
Flood cause: Heavy Rain
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Twelve to 18 inches of water flowing across Delaware Ave north of Oralabor Rd.

Thunderstorm Wind in UNION, IOWA
From 14-APR-12 18:04:00 to 14-APR-12 18:04:00 (CST-6)
Location: CRESTON
Magnitude: 69.00 EG
Property damage: 250.00K
Crop damage: 0.00K
Reported by: Amateur Radio

Twenty inch tree down with other large trees uprooted.

Thunderstorm Wind in MADISON, IOWA
From 14-APR-12 18:30:00 to 14-APR-12 18:30:00 (CST-6)
Location: WINTERSET
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Estimated winds at intersection of Highway 169 and 92 west of Winterset.

Heavy Rain in JASPER, IOWA
From 15-APR-12 06:00:00 to 15-APR-12 06:00:00 (CST-6)
Location: PRAIRIE CITY
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Rainfall of 2.21 inches in 24 hours.

Heavy Rain in UNION, IOWA
From 15-APR-12 06:00:00 to 15-APR-12 06:00:00 (CST-6)
Location: LORIMOR
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Rainfall of 2.45 inches in 24 hours.

Heavy Rain in POLK, IOWA
From 15-APR-12 06:00:00 to 15-APR-12 06:00:00 (CST-6)
Location: WINDSOR HGTS
Property damage: 0.00K
Crop damage: 0.00K
Reported by: NWS Employee

Rainfall of 2.27 inches in 24 hours.

Flash Flood in CASS, IOWA
From 14-APR-12 17:53:00 to 14-APR-12 21:00:00 (CST-6)
Location: ATLANTIC
Flood cause: Heavy Rain
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Flash flooding reported in Atlantic with water at least 18 inches deep covering the roads.

Flash Flood in POLK, IOWA
From 14-APR-12 19:20:00 to 14-APR-12 21:30:00 (CST-6)
Location: ORALABOR
Flood cause: Heavy Rain
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Street flooding reported with one to two feet in Ankeny near the HyVee and High School by 1st street.

Heavy Rain in MADISON, IOWA
From 14-APR-12 15:26:00 to 14-APR-12 15:56:00 (CST-6)
Location: WINTERSET
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Amateur Radio

One and one half inches of rain fell in 30 minutes.

Heavy Rain in ADAIR, IOWA
From 14-APR-12 14:00:00 to 14-APR-12 18:00:00 (CST-6)
Location: ORIENT
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

One and one half inches of rain before 1600 CST and an additional two and one half inches from 1600 to 1800 CST.

Thunderstorm Wind in DALLAS, IOWA
From 14-APR-12 18:39:00 to 14-APR-12 18:39:00 (CST-6)
Location: ORTONVILLE
Magnitude: 61.00 EG
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trained spotter estimated winds gusting to 70 MPH.

Thunderstorm Wind in POLK, IOWA
From 14-APR-12 18:51:00 to 14-APR-12 18:51:00 (CST-6)
Location: DES MOINES
Magnitude: 56.00 MG
Property damage: 50.00K
Crop damage: 0.00K
Reported by: Mesonet

South wind of 65 MPH was measured at the Blank Park Zoo.

Thunderstorm Wind in POLK, IOWA
From 14-APR-12 18:45:00 to 14-APR-12 18:55:00 (CST-6)
Location: ANKENY
Magnitude: 56.00 EG
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Winds of 60 to 65 MPH lasted about 10 minutes.

Thunderstorm Wind in CLARKE, IOWA
From 14-APR-12 18:39:00 to 14-APR-12 18:39:00 (CST-6)
Location: OSCEOLA MUNI ARPT
Magnitude: 52.00 EG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Winds were estimated to be around 60 MPH.

Thunderstorm Wind in CLARKE, IOWA
From 14-APR-12 18:51:00 to 14-APR-12 18:51:00 (CST-6)
Location: OSCEOLA
Magnitude: 52.00 EG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Estimated winds of 60 MPH.

Thunderstorm Wind in POLK, IOWA
From 14-APR-12 19:02:00 to 14-APR-12 19:02:00 (CST-6)
Location: LOVINGTON
Magnitude: 52.00 EG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Estimated winds of 60 MPH.

Thunderstorm Wind in MAHASKA, IOWA
From 14-APR-12 20:15:00 to 14-APR-12 20:15:00 (CST-6)
Location: OSKALOOSA
Magnitude: 52.00 EG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Estimated winds of 60 MPH along with pea size hail.

Thunderstorm Wind in MADISON, IOWA
From 14-APR-12 15:41:00 to 14-APR-12 15:41:00 (CST-6)
Location: WINTERSET
Magnitude: 52.00 EG
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Wind blew over road signs.

Thunderstorm Wind in CASS, IOWA
From 14-APR-12 17:44:00 to 14-APR-12 17:44:00 (CST-6)
Location: ATLANTIC
Magnitude: 52.00 EG
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Public

Shingles were blown off of a house.  Small branches were broken off.

Thunderstorm Wind in POWESHIEK, IOWA
From 14-APR-12 19:50:00 to 14-APR-12 19:50:00 (CST-6)
Location: SEARSBORO
Magnitude: 52.00 EG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Estimated 60 MPH winds.