A very unstable airmass on May 19, 2013 led to the development of severe thunderstorms that produced large hail and damaging winds. Temperatures were in the 80s with dewpoints around 70 with a mid level speed maximum rotating around the base of a developing upper low in the Plains states. This increased the deep layer shear during the afternoon and evening hours. Some of the storms produced golf to baseball size hail and 70 to 80 mph winds. A trained spotter reported baseball size hail knocked out sky lights at the Walmart store in northeast Keokuk. Golfball to baseball size hail was reported on the north end of the city, with nickel to quarter size hail on the south end of the city. A downburst produced wind damage in Benton county from the county line 3.5 miles southeast of Blairstown to 2.8 miles southeast of Shellsburg. There was a mile wide swath of near continuous damage to farm outbuildings, tree branches and some power poles. The greatest damage was from 3 miles south of Newhall, where a machine shed and garage were completely destroyed, to about 3 miles northwest of Atkins, where significant damage occurred to outbuildings. The emergency manager in Buchanan county reported a downburst with winds more than 70 mph struck Independence, Iowa. The northwest side of town sustained the most damage with trees down, power poles snapped and signs blown down.

Hail in HANCOCK, ILLINOIS
From 19-MAY-13 16:38:00 to 19-MAY-13 16:38:00 (CST-6)
Location: HAMILTON
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Thunderstorm Wind in MERCER, ILLINOIS
From 19-MAY-13 17:45:00 to 19-MAY-13 17:45:00 (CST-6)
Location: NEW WINDSOR
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Law enforcement reported trees down near U.S. Highway 67 south of 50th Street.

Thunderstorm Wind in HENRY, ILLINOIS
From 19-MAY-13 17:50:00 to 19-MAY-13 17:50:00 (CST-6)
Location: ALPHA
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Law enforcement reported trees down.

Hail in ROCK ISLAND, ILLINOIS
From 19-MAY-13 17:46:00 to 19-MAY-13 17:46:00 (CST-6)
Location: MOLINE
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in WARREN, ILLINOIS
From 19-MAY-13 18:01:00 to 19-MAY-13 18:01:00 (CST-6)
Location: SMITHSHIRE
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in WHITESIDE, ILLINOIS
From 19-MAY-13 18:38:00 to 19-MAY-13 18:38:00 (CST-6)
Location: ALBANY
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Thunderstorm Wind in HENRY, ILLINOIS
From 19-MAY-13 18:09:00 to 19-MAY-13 18:09:00 (CST-6)
Location: CAMBRIDGE
Magnitude: 50.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Law enforcement reported trees down.

Thunderstorm Wind in CARROLL, ILLINOIS
From 19-MAY-13 19:10:00 to 19-MAY-13 19:10:00 (CST-6)
Location: MT CARROLL
Magnitude: 50.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter several locations along Highway 78 south of Mount Carroll with trees and power lines down.

Thunderstorm Wind in WHITESIDE, ILLINOIS
From 19-MAY-13 19:30:00 to 19-MAY-13 19:30:00 (CST-6)
Location: UNIONVILLE
Magnitude: 50.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter reported several 5 inch limbs down.

Thunderstorm Wind in STEPHENSON, ILLINOIS
From 19-MAY-13 19:45:00 to 19-MAY-13 19:45:00 (CST-6)
Location: FREEPORT
Magnitude: 50.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter reported several tree branches down in town.

Thunderstorm Wind in JO DAVIESS, ILLINOIS
From 19-MAY-13 13:07:00 to 19-MAY-13 13:07:00 (CST-6)
Location: STOCKTON
Magnitude: 56.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

A COOP observer measured 65 mph winds.

Thunderstorm Wind in HENRY, ILLINOIS
From 19-MAY-13 18:03:00 to 19-MAY-13 18:03:00 (CST-6)
Location: CAMBRIDGE
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter measured 62 mph winds ahead of the storms and there was a lot of blowing dust.

Thunderstorm Wind in WHITESIDE, ILLINOIS
From 19-MAY-13 18:49:00 to 19-MAY-13 18:49:00 (CST-6)
Location: USTICK
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter estimated 50 to 60 mph winds and pea size hail.

Thunderstorm Wind in WHITESIDE, ILLINOIS
From 19-MAY-13 18:55:00 to 19-MAY-13 18:55:00 (CST-6)
Location: STERLING
Magnitude: 50.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter measured 60 mph winds.

Hail in JO DAVIESS, ILLINOIS
From 19-MAY-13 12:45:00 to 19-MAY-13 12:45:00 (CST-6)
Location: HANOVER
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in HENDERSON, ILLINOIS
From 19-MAY-13 16:03:00 to 19-MAY-13 16:03:00 (CST-6)
Location: LOMAX
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in HENRY, ILLINOIS
From 19-MAY-13 18:42:00 to 19-MAY-13 18:42:00 (CST-6)
Location: GALVA
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Tornado in CARROLL, ILLINOIS
From 19-MAY-13 19:02:00 to 19-MAY-13 19:02:00 (CST-6)
Location: IDEAL
Tornado F-scale: EF0
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Confirmed tornado heading towards Chadwick.

Hail in HANCOCK, ILLINOIS
From 19-MAY-13 16:17:00 to 19-MAY-13 16:17:00 (CST-6)
Location: WARSAW
Magnitude: 1.25 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

The time of this report was estimated based off of radar data.

Hail in HANCOCK, ILLINOIS
From 19-MAY-13 16:21:00 to 19-MAY-13 16:21:00 (CST-6)
Location: WARSAW
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Thunderstorm Wind in JO DAVIESS, ILLINOIS
From 19-MAY-13 12:59:00 to 19-MAY-13 12:59:00 (CST-6)
Location: APPLE CANYON LAKE
Magnitude: 50.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter measured 2 inch diameter tree limbs down.

Thunderstorm Wind in JO DAVIESS, ILLINOIS
From 19-MAY-13 13:07:00 to 19-MAY-13 13:07:00 (CST-6)
Location: STOCKTON
Magnitude: 50.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

A COOP observer measured a 4 inch diameter tree limb down at the residence.