A warm front extended from eastern Nebraska to western Illinois and was lifting northward on June 16-17, 2014.  An extremely unstable air mass was over the area on June 16 along with strong deep layer shear.  This allowed scattered supercells to form during the afternoon and evening which produced two tornadoes, very large hail and damaging winds.  A weak tornado formed 4 miles south of Lamont, Iowa in Buchanan County, tracked about 1 mile to the northeast before crossing into Delaware County. In Delaware County the tornado continued for about 13 miles to the northeast to Edgewood, Iowa.  Another weak tornado briefly touched down in Benton County, Iowa. Strengthening mid level winds along with a strong low level jet in place later in the evening and overnight on June 17 produced widespread damaging winds of 60 to 70 mph.  Strong warm air advection triggered more severe thunderstorms during the late evening of June 17.

Thunderstorm Wind in CEDAR, IOWA
From 17-JUN-14 02:25:00 to 17-JUN-14 02:25:00 (CST-6)
Location: LIME CITY
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter reported a barn blown down on a car with numerous trees uprooted. A fence was blown down and parts of the barn blown into the tree.

Thunderstorm Wind in CEDAR, IOWA
From 17-JUN-14 02:30:00 to 17-JUN-14 02:30:00 (CST-6)
Location: LOWDEN
Magnitude: 50.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

A COOP observer reported tree limbs down in town.

Thunderstorm Wind in LINN, IOWA
From 16-JUN-14 21:20:00 to 16-JUN-14 21:20:00 (CST-6)
Location: BEVERLY
Magnitude: 63.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

The Fairfax Fire Department reported 70 mph winds relayed by the emergency manager.

Thunderstorm Wind in LINN, IOWA
From 16-JUN-14 21:26:00 to 16-JUN-14 21:26:00 (CST-6)
Location: CEDAR RAPIDS
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter reported 60 mph winds near Interstate 380 and Highway 100.

Thunderstorm Wind in BENTON, IOWA
From 16-JUN-14 20:53:00 to 16-JUN-14 20:53:00 (CST-6)
Location: VAN HORNE
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

The emergency manager reported trees and power poles down 1 to 2 miles west of Van Horne.

Thunderstorm Wind in SCOTT, IOWA
From 17-JUN-14 02:55:00 to 17-JUN-14 02:55:00 (CST-6)
Location: DAVENPORT
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter reported 60 mph winds.

Thunderstorm Wind in SCOTT, IOWA
From 17-JUN-14 02:35:00 to 17-JUN-14 02:35:00 (CST-6)
Location: DIXON
Magnitude: 60.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

The public reported damage 2 miles south of Dixon on County Y40. Several outbuildings and trees were blown down on a farm with debris blown into nearby fields. The damage was very localized.

Thunderstorm Wind in JONES, IOWA
From 16-JUN-14 15:55:00 to 16-JUN-14 15:55:00 (CST-6)
Location: MARTELLE
Magnitude: 55.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A roof was blown off a building and landed 200 to 300 feet away.

Thunderstorm Wind in DELAWARE, IOWA
From 16-JUN-14 16:30:00 to 16-JUN-14 16:30:00 (CST-6)
Location: SAND SPG
Magnitude: 50.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

The public reported several tree branches down.

Thunderstorm Wind in DELAWARE, IOWA
From 16-JUN-14 16:30:00 to 16-JUN-14 16:30:00 (CST-6)
Location: SAND SPG
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

The public reported a large tree blown down.

Thunderstorm Wind in DELAWARE, IOWA
From 16-JUN-14 21:00:00 to 16-JUN-14 21:00:00 (CST-6)
Location: EDGEWOOD
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter reported two buildings damaged on a farm along with a tree and power pole blown down.

Thunderstorm Wind in LINN, IOWA
From 16-JUN-14 21:10:00 to 16-JUN-14 21:10:00 (CST-6)
Location: CEDAR RAPIDS
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

The public reported a large tree fell on the river gauge site on the Cedar River in town.

Thunderstorm Wind in LINN, IOWA
From 16-JUN-14 21:28:00 to 16-JUN-14 21:28:00 (CST-6)
Location: CEDAR RAPIDS
Magnitude: 60.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter reported extensive tree damage from the intersection of Johnson and Edgewood to 6th Street and Wilson.  Several full grown trees were snapped off the base of the tree.

Thunderstorm Wind in LINN, IOWA
From 16-JUN-14 21:28:00 to 16-JUN-14 21:28:00 (CST-6)
Location: CEDAR RAPIDS
Magnitude: 60.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Tree damage reported with the largest uprooted.

Hail in JOHNSON, IOWA
From 16-JUN-14 15:24:00 to 16-JUN-14 15:24:00 (CST-6)
Location: IOWA CITY
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

The public reported hail to the size of quarters near Interstate 80 exit 246.

Hail in LINN, IOWA
From 16-JUN-14 15:44:00 to 16-JUN-14 15:44:00 (CST-6)
Location: MT VERNON
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Law enforcement reported hail the size of quarters.

Hail in JONES, IOWA
From 16-JUN-14 15:59:00 to 16-JUN-14 15:59:00 (CST-6)
Location: FAIRVIEW
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter reported nickel size hail.

Thunderstorm Wind in JOHNSON, IOWA
From 16-JUN-14 21:35:00 to 16-JUN-14 21:35:00 (CST-6)
Location: SWISHER
Magnitude: 50.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Large tree branches of 15 inches in diameter blown down.

Hail in JONES, IOWA
From 16-JUN-14 16:05:00 to 16-JUN-14 16:05:00 (CST-6)
Location: ANAMOSA
Magnitude: 1.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Law enforcement reported ping pong ball size hail.

Hail in LINN, IOWA
From 16-JUN-14 16:05:00 to 16-JUN-14 16:06:00 (CST-6)
Location: PRAIRIEBURG
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter reported penny size hail and winds estimated at 50 mph. Small tree limbs were also blown down.  The hail lasted one minute.

Thunderstorm Wind in SCOTT, IOWA
From 17-JUN-14 02:50:00 to 17-JUN-14 02:50:00 (CST-6)
Location: DAVENPORT
Magnitude: 50.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

The public reported a large tree branch 10 inches in diameter blown down near 34th and Division in Davenport.

Hail in DELAWARE, IOWA
From 16-JUN-14 16:30:00 to 16-JUN-14 16:30:00 (CST-6)
Location: SAND SPG
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

The public reported hail the size of quarters.

Thunderstorm Wind in SCOTT, IOWA
From 17-JUN-14 02:55:00 to 17-JUN-14 02:55:00 (CST-6)
Location: SCOTT COUNTY PARK
Magnitude: 60.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

Numerous trees were snapped and tree limbs blown down in and around the southwest corner of Scott county park.

Thunderstorm Wind in SCOTT, IOWA
From 17-JUN-14 03:00:00 to 17-JUN-14 03:00:00 (CST-6)
Location: SCOTT COUNTY PARK
Magnitude: 50.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

A barn under construction was blown down.

Hail in DUBUQUE, IOWA
From 17-JUN-14 21:45:00 to 17-JUN-14 21:45:00 (CST-6)
Location: KEY WEST
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter reported hail the size of quarters.

Thunderstorm Wind in LINN, IOWA
From 17-JUN-14 02:30:00 to 17-JUN-14 02:30:00 (CST-6)
Location: CEDAR RAPIDS
Magnitude: 60.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

The emergency manager reported the gym roof completely blown off of Trinity Lutheran School at 1361 7th avenue SW.

Thunderstorm Wind in WASHINGTON, IOWA
From 16-JUN-14 14:32:00 to 16-JUN-14 14:32:00 (CST-6)
Location: WASHINGTON ARPT
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Small limbs were down due to 50 to 60 mph winds.

Thunderstorm Wind in WASHINGTON, IOWA
From 16-JUN-14 14:46:00 to 16-JUN-14 14:46:00 (CST-6)
Location: WASHINGTON
Magnitude: 58.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Wind gust measured by AWOS.

Hail in DUBUQUE, IOWA
From 17-JUN-14 21:59:00 to 17-JUN-14 21:59:00 (CST-6)
Location: KEY WEST
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

The public reported golf ball size hail.

Hail in DUBUQUE, IOWA
From 17-JUN-14 22:05:00 to 17-JUN-14 22:05:00 (CST-6)
Location: CENTER GROVE
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

The public reported hail the size of quarters.

Thunderstorm Wind in MUSCATINE, IOWA
From 17-JUN-14 02:40:00 to 17-JUN-14 02:40:00 (CST-6)
Location: STOCKTON
Magnitude: 50.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter reported several 5 to 6 inch diameter tree limbs down.

Thunderstorm Wind in CLINTON, IOWA
From 17-JUN-14 02:42:00 to 17-JUN-14 02:42:00 (CST-6)
Location: CALAMUS
Magnitude: 60.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter reported trees down all over town along with shingles blown off roofs.

Thunderstorm Wind in SCOTT, IOWA
From 17-JUN-14 02:50:00 to 17-JUN-14 02:50:00 (CST-6)
Location: DAVENPORT
Magnitude: 50.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter observed a 6 inch oak limb down at the National Guard Armory on North Division in Davenport.

Thunderstorm Wind in JOHNSON, IOWA
From 16-JUN-14 15:00:00 to 16-JUN-14 15:00:00 (CST-6)
Location: HILLS
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter reported 60 mph winds along with small tree limbs down.

Thunderstorm Wind in JOHNSON, IOWA
From 16-JUN-14 15:15:00 to 16-JUN-14 15:15:00 (CST-6)
Location: UNIVERSITY HGTS
Magnitude: 60.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter reported a healthy maple tree two feet in diameter was snapped at the base.

Hail in JONES, IOWA
From 16-JUN-14 16:00:00 to 16-JUN-14 16:00:00 (CST-6)
Location: MARTELLE
Magnitude: 1.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

The emergency manager reported ping pong ball size hail along with power lines down.

Hail in JONES, IOWA
From 16-JUN-14 16:01:00 to 16-JUN-14 16:01:00 (CST-6)
Location: AMBER
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter measured hail the size of quarters.

Hail in JONES, IOWA
From 16-JUN-14 16:03:00 to 16-JUN-14 16:03:00 (CST-6)
Location: ANAMOSA
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter measured golf ball size hail.

Thunderstorm Wind in CEDAR, IOWA
From 17-JUN-14 02:25:00 to 17-JUN-14 02:25:00 (CST-6)
Location: LIME CITY
Magnitude: 61.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

The public estimated winds of 70 mph.

Thunderstorm Wind in JONES, IOWA
From 16-JUN-14 15:50:00 to 16-JUN-14 15:50:00 (CST-6)
Location: MARTELLE
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter reported a path of damage from 1 mile west of Martelle to 2 miles east of Martelle. Trees of 6 to 12 inches in diameter were blown down and one tree had a diameter of 3 feet. An old barn and silo were also blown down.

Thunderstorm Wind in CEDAR, IOWA
From 17-JUN-14 02:25:00 to 17-JUN-14 02:25:00 (CST-6)
Location: LIME CITY
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

The public reported a large outbuilding damaged.

Thunderstorm Wind in WASHINGTON, IOWA
From 16-JUN-14 14:35:00 to 16-JUN-14 14:35:00 (CST-6)
Location: WASHINGTON
Magnitude: 58.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Wind gust measured by AWOS.

Thunderstorm Wind in JONES, IOWA
From 16-JUN-14 16:01:00 to 16-JUN-14 16:01:00 (CST-6)
Location: AMBER
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter reported 60 mph winds.

Thunderstorm Wind in BENTON, IOWA
From 16-JUN-14 20:39:00 to 16-JUN-14 20:39:00 (CST-6)
Location: KEYSTONE
Magnitude: 61.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

The emergency manager reported 70 mph winds at the Keystone Fire Department.

Thunderstorm Wind in LINN, IOWA
From 16-JUN-14 21:28:00 to 16-JUN-14 21:28:00 (CST-6)
Location: CEDAR RAPIDS
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter reported 60 mph winds near Interstate 80 and Highway 100.

Hail in JEFFERSON, IOWA
From 16-JUN-14 14:09:00 to 16-JUN-14 14:09:00 (CST-6)
Location: LOCKRIDGE
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter observed dime to penny size hail along with 50 mph winds.

Hail in HENRY, IOWA
From 16-JUN-14 14:20:00 to 16-JUN-14 14:20:00 (CST-6)
Location: WAYLAND
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Law enforcement reported hail the size of quarters.

Hail in HENRY, IOWA
From 16-JUN-14 14:25:00 to 16-JUN-14 14:25:00 (CST-6)
Location: WAYLAND
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter reported dime to quarter size hail.

Thunderstorm Wind in SCOTT, IOWA
From 17-JUN-14 02:57:00 to 17-JUN-14 02:57:00 (CST-6)
Location: SCOTT COUNTY PARK
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: NWS Employee

Small tree branches down due to 60 mph winds.

Thunderstorm Wind in CLINTON, IOWA
From 17-JUN-14 02:53:00 to 17-JUN-14 02:53:00 (CST-6)
Location: DEWITT
Magnitude: 62.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Department of Highways

Measured by RWIS station.

Thunderstorm Wind in CLINTON, IOWA
From 17-JUN-14 03:15:00 to 17-JUN-14 03:15:00 (CST-6)
Location: CLINTON MUNI ARPT
Magnitude: 50.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Winds of 58 mph was measured by AWOS site.

Hail in HENRY, IOWA
From 16-JUN-14 14:30:00 to 16-JUN-14 14:30:00 (CST-6)
Location: WAYLAND
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter reported dime to quarter size hail.

Thunderstorm Wind in DELAWARE, IOWA
From 16-JUN-14 20:46:00 to 16-JUN-14 20:46:00 (CST-6)
Location: MANCHESTER ARPT
Magnitude: 61.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

The emergency manager relayed a report of 70 mph winds from the Manchester Fire Department.

Thunderstorm Wind in BENTON, IOWA
From 16-JUN-14 20:48:00 to 16-JUN-14 20:48:00 (CST-6)
Location: VAN HORNE
Magnitude: 54.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter reported 60 mph winds.

Hail in WASHINGTON, IOWA
From 16-JUN-14 14:55:00 to 16-JUN-14 14:55:00 (CST-6)
Location: RIVERSIDE
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

The public reported hail up to the size of dimes along with 50 mph winds.

Hail in JOHNSON, IOWA
From 16-JUN-14 15:15:00 to 16-JUN-14 15:15:00 (CST-6)
Location: IOWA CITY
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter reported hail the size of quarters.

Thunderstorm Wind in WASHINGTON, IOWA
From 17-JUN-14 02:15:00 to 17-JUN-14 02:15:00 (CST-6)
Location: WASHINGTON
Magnitude: 51.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Winds were measured by an AWOS station.

Thunderstorm Wind in CEDAR, IOWA
From 17-JUN-14 02:32:00 to 17-JUN-14 02:32:00 (CST-6)
Location: LOWDEN
Magnitude: 50.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A hog confinement building roof was blown off.

Thunderstorm Wind in SCOTT, IOWA
From 17-JUN-14 02:55:00 to 17-JUN-14 02:55:00 (CST-6)
Location: SCOTT COUNTY PARK
Magnitude: 50.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: NWS Employee

A 10 inch diameter tree was snapped off 5 feet from the ground near the water tower.

Thunderstorm Wind in BENTON, IOWA
From 16-JUN-14 20:59:00 to 16-JUN-14 20:59:00 (CST-6)
Location: VAN HORNE
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

The emergency manager reported 60 mph winds.

Thunderstorm Wind in SCOTT, IOWA
From 17-JUN-14 02:55:00 to 17-JUN-14 02:55:00 (CST-6)
Location: DAVENPORT
Magnitude: 50.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter reported large tree limbs down near 53rd and Division in Davenport.

Thunderstorm Wind in JOHNSON, IOWA
From 16-JUN-14 21:35:00 to 16-JUN-14 21:35:00 (CST-6)
Location: SWISHER
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter measured 60 mph winds.

Flash Flood in BUCHANAN, IOWA
From 16-JUN-14 20:50:00 to 16-JUN-14 20:50:00 (CST-6)
Location: INDEPENDENCE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter reported streets were flooding due to storm sewers not keeping up with the heavy rain.

Hail in VAN BUREN, IOWA
From 16-JUN-14 13:30:00 to 16-JUN-14 13:30:00 (CST-6)
Location: BONAPARTE
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Law enforcement reported golf ball size hail along with torrential rain.

Hail in HENRY, IOWA
From 16-JUN-14 13:42:00 to 16-JUN-14 13:42:00 (CST-6)
Location: HILLSBORO
Magnitude: 1.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter reported ping pong ball size hail.

Hail in JOHNSON, IOWA
From 16-JUN-14 15:20:00 to 16-JUN-14 15:20:00 (CST-6)
Location: IOWA CITY
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

The public reported penny size hail.

Hail in JOHNSON, IOWA
From 16-JUN-14 15:21:00 to 16-JUN-14 15:21:00 (CST-6)
Location: IOWA CITY
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Golf ball size hail was reported at the intersection of Highway 6 and Scott boulevard.

Hail in JOHNSON, IOWA
From 16-JUN-14 15:22:00 to 16-JUN-14 15:22:00 (CST-6)
Location: IOWA CITY
Magnitude: 1.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter reported ping pong ball size hail.