A strong push of warm air took place during the day on the 3rd in advance of a strong low pressure area.  Temperatures warmed in to the mid to upper 80s across a large part of the state, with dewpoint readings in the mid 50s to low 60s.  While the low levels appeared to be quite unstable, a strong elevated mixed layer was in place over the state.  This effectively capped convection until very late in the afternoon.  By evening, most unstable CAPE values were in the 2000 to 3000 J/kg range.  Downdraft CAPE values were between 1000 and 1300 J/kg, and lifted indices were between -6 and -8 C.  There was sufficient shear available with 45 to 50 kts of available shear.  Available CAPE in the -10 to -30 C layer of the atmosphere was 400 to 700 J/kg.  The freezing level was quite high for the time of the year at around 13,000 feet, as was the LCL at around 1500 meters.  This limited the tornado potential.  Thunderstorms were slow to fire, but once they did, the development was explosive.  Thunderstorms went from the developing stage to severe in 5 to 10 minutes.  Thunderstorms dropped quarter size hail in Mahaska County.  As the storm matured, hail sizes increased to golf ball size.  The storm quickly moved into Poweshiek County and produced quarter size hail near Montezuma.  The storms moved quickly east of the Des Moines CWA.  An upper level impulse raced northeast along the back side of the cold front that had just passed through.  Thunderstorms formed in response to this feature.  Most of them were left splitters and produced hail of pea to dime size.  One storm dropped ping pong ball size hail west of Gravity in Taylor County.  This area of storms moved northeast, producing hail, but the only other report of severe hail was northwest of Bedford in Taylor County, where one and one quarter inch hail fell.  The storms moved from southwest Iowa into central Iowa at nearly 90 MPH and produced penny size hail as they moved through the metro Des Moines area.  Later in the evening, another round of thunderstorms moved northeast on the back side of the cold front.  These storms produced spotty nickel size hail across southeast Iowa.

Hail in MAHASKA, IOWA
From 03-APR-11 17:11:00 to 03-APR-11 17:11:00 (CST-6)
Location: NEW SHARON
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in MAHASKA, IOWA
From 03-APR-11 17:56:00 to 03-APR-11 17:56:00 (CST-6)
Location: FREMONT
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in TAYLOR, IOWA
From 03-APR-11 19:48:00 to 03-APR-11 19:48:00 (CST-6)
Location: BEDFORD
Magnitude: 1.25 
Property damage: 2.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Hail in TAYLOR, IOWA
From 03-APR-11 19:45:00 to 03-APR-11 19:45:00 (CST-6)
Location: GRAVITY
Magnitude: 1.50 
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in POLK, IOWA
From 03-APR-11 20:50:00 to 03-APR-11 20:50:00 (CST-6)
Location: WINDSOR HGTS
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Located at Hickman and 70th St.

Hail in MARION, IOWA
From 03-APR-11 22:10:00 to 03-APR-11 22:10:00 (CST-6)
Location: PLEASANTVILLE
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Hail in LUCAS, IOWA
From 03-APR-11 22:22:00 to 03-APR-11 22:22:00 (CST-6)
Location: LUCAS
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in MARION, IOWA
From 03-APR-11 22:47:00 to 03-APR-11 22:47:00 (CST-6)
Location: PELLA
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Hail in MAHASKA, IOWA
From 03-APR-11 17:07:00 to 03-APR-11 17:07:00 (CST-6)
Location: LEIGHTON
Magnitude: 1.75 
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Public

Reported by a KCCI television viewer.

Hail in POWESHIEK, IOWA
From 03-APR-11 17:20:00 to 03-APR-11 17:20:00 (CST-6)
Location: MONTEZUMA
Magnitude: 1.00 
Property damage: 1.00K
Crop damage: 0.00K
Reported by: Public

Hail was reported by a KCCI television viewer.