Severe thunderstorms moved across many areas of northern Illinois during the afternoon and evening hours of May 22nd.  Heavy rain produced flash flooding in some areas and tornadoes were reported with some of the strongest storms that moved across far northern Illinois during the early evening hours.

Flood in LIVINGSTON, ILLINOIS
From 22-MAY-11 15:00:00 to 22-MAY-11 16:00:00 (CST-6)
Location: ROOKS CREEK
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

Water was overflowing many streets in Pontiac after 1.12 inches of rain fell in 30 minutes.

Thunderstorm Wind in FORD, ILLINOIS
From 22-MAY-11 15:36:00 to 22-MAY-11 15:36:00 (CST-6)
Location: GARBER
Magnitude: 60.00 EG
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Public

A semi truck was blown off of Route 47, about four miles south of Sibley.

Thunderstorm Wind in WINNEBAGO, ILLINOIS
From 22-MAY-11 17:58:00 to 22-MAY-11 17:58:00 (CST-6)
Location: SOUTH BELOIT
Magnitude: 65.00 EG
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Newspaper

Several storage buildings sustained roof damage near Route 251 and Rockton Road.

Thunderstorm Wind in IROQUOIS, ILLINOIS
From 22-MAY-11 14:40:00 to 22-MAY-11 14:40:00 (CST-6)
Location: CLIFTON
Magnitude: 60.00 EG
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A semi truck rolled over on Interstate 57 near Clifton.

Lightning in WINNEBAGO, ILLINOIS
From 22-MAY-11 21:00:00 to 22-MAY-11 21:00:00 (CST-6)
Location: SEWARD
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Newspaper

Lightning struck a pig-confined building along Kelley Road in Pecatonica.  The damage was confined to the utility room and no livestock was lost.

Thunderstorm Wind in WINNEBAGO, ILLINOIS
From 22-MAY-11 17:35:00 to 22-MAY-11 17:35:00 (CST-6)
Location: PECATONICA
Magnitude: 60.00 EG
Property damage: 1.00K
Crop damage: 0.00K
Reported by: Newspaper

Large tree limbs and power lines were blown down.

Thunderstorm Wind in WINNEBAGO, ILLINOIS
From 22-MAY-11 17:57:00 to 22-MAY-11 17:57:00 (CST-6)
Location: COLONIAL GARDENS
Magnitude: 60.00 EG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Newspaper

Tree limbs, utility poles and power lines were blown down in many areas of Machesney Park.

Thunderstorm Wind in LIVINGSTON, ILLINOIS
From 22-MAY-11 13:51:00 to 22-MAY-11 13:51:00 (CST-6)
Location: PONTIAC
Magnitude: 52.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in DU PAGE, ILLINOIS
From 22-MAY-11 14:10:00 to 22-MAY-11 14:12:00 (CST-6)
Location: FLOWERFIELD
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Penny to quarter size hail was reported in Lombard. The quarter size hail report was from West Madison Street.

Thunderstorm Wind in LIVINGSTON, ILLINOIS
From 22-MAY-11 14:18:00 to 22-MAY-11 14:18:00 (CST-6)
Location: FORREST
Magnitude: 52.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Power was lost after a 60 mph wind gust.

Hail in LAKE, ILLINOIS
From 22-MAY-11 14:36:00 to 22-MAY-11 14:37:00 (CST-6)
Location: WAUKEGAN
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Nickel size hail was reported at the intersection of Jackson Street and Belvidere Street.

Hail in COOK, ILLINOIS
From 22-MAY-11 14:45:00 to 22-MAY-11 14:48:00 (CST-6)
Location: MORTON GROVE
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in OGLE, ILLINOIS
From 22-MAY-11 15:25:00 to 22-MAY-11 15:26:00 (CST-6)
Location: POLO
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Hail in OGLE, ILLINOIS
From 22-MAY-11 16:09:00 to 22-MAY-11 16:12:00 (CST-6)
Location: MT MORRIS
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Penny to Quarter size hail was reported in Mount Morris.

Hail in WINNEBAGO, ILLINOIS
From 22-MAY-11 16:36:00 to 22-MAY-11 16:39:00 (CST-6)
Location: LOVES PARK
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Quarter size hail was reported at the intersection of Route 251 and Loves Park Drive.

Hail in WINNEBAGO, ILLINOIS
From 22-MAY-11 17:05:00 to 22-MAY-11 17:08:00 (CST-6)
Location: PECATONICA
Magnitude: 1.25 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Thunderstorm Wind in OGLE, ILLINOIS
From 22-MAY-11 17:34:00 to 22-MAY-11 17:40:00 (CST-6)
Location: MT MORRIS
Magnitude: 70.00 EG
Reported by: Trained Spotter

Estimated 70 to 80 mph winds just south of Mount Morris snapped power poles and caused heavy damage to barns and buildings in the area.

Thunderstorm Wind in WINNEBAGO, ILLINOIS
From 22-MAY-11 17:54:00 to 22-MAY-11 17:54:00 (CST-6)
Location: (RFD)GTR ROCKFORD AR
Magnitude: 53.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Hail in BOONE, ILLINOIS
From 22-MAY-11 18:10:00 to 22-MAY-11 18:12:00 (CST-6)
Location: BELVIDERE
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Quarter size hail was reported between Interstate 90 and Highway 20 near Genoa Road.

Hail in OGLE, ILLINOIS
From 22-MAY-11 19:10:00 to 22-MAY-11 19:11:00 (CST-6)
Location: MONROE CENTER
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Nickel size hail was reported at Interstate 39 and Route 72.

Hail in LAKE, ILLINOIS
From 22-MAY-11 19:28:00 to 22-MAY-11 19:29:00 (CST-6)
Location: NORTH BARRINGTON
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Nickel size hail was reported near the intersection of Route 12 and Old McHenry Road.

Hail in LAKE, ILLINOIS
From 22-MAY-11 19:35:00 to 22-MAY-11 19:36:00 (CST-6)
Location: MUNDELEIN
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

Hail in OGLE, ILLINOIS
From 22-MAY-11 17:50:00 to 22-MAY-11 17:51:00 (CST-6)
Location: STILLMAN VLY
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Nickel size hail fell just north of Stillman Valley on Stillman Valley Road.

Hail in LIVINGSTON, ILLINOIS
From 22-MAY-11 13:51:00 to 22-MAY-11 13:52:00 (CST-6)
Location: PONTIAC
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Nickel to quarter size hail was reported in Pontiac.

Tornado in OGLE, ILLINOIS
From 22-MAY-11 17:40:00 to 22-MAY-11 17:42:00 (CST-6)
Location: STILLMAN VLY
Tornado F-scale: EF1
Property damage: 50.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

A brief tornado took out a dual wood truss electrical transmission line tower, tore off the gable and part of the roof of a house, peeled soffit and shingles from a couple other houses, and knocked down trees and limbs. Truck trailers were also overturned. The tornado was rated EF1 with estimated winds of 90 to 110 mph.

Thunderstorm Wind in IROQUOIS, ILLINOIS
From 22-MAY-11 14:43:00 to 22-MAY-11 14:43:00 (CST-6)
Location: ASHKUM
Magnitude: 60.00 EG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Emergency Manager

A tree was reported down and a grain bin was blown over when a line of strong thunderstorms hit the town of Ashkum.

Thunderstorm Wind in WINNEBAGO, ILLINOIS
From 22-MAY-11 17:58:00 to 22-MAY-11 18:09:00 (CST-6)
Location: ROSCOE
Magnitude: 52.00 EG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Estimated 60 mph wind gusts in the town of Roscoe downed tree branches, bent a Dairy Queen flagpole in half, and caused damage at the Roscoe Fire Department including their training facility.

Hail in KANKAKEE, ILLINOIS
From 22-MAY-11 14:46:00 to 22-MAY-11 14:50:00 (CST-6)
Location: WEST KANKAKEE
Magnitude: 1.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Up to walnut size hail was reported across portions of Bradley and Kankakee as a line of thunderstorms moved through.  Specific reports include penny size hail at the intersection of Grinnell Road and Interstate 57, and nickel size hail at the intersection of West Station Street and South Curtis Avenue.  Walnut size hail was reported at North Street and Illinois Route 50.

Thunderstorm Wind in FORD, ILLINOIS
From 22-MAY-11 15:47:00 to 22-MAY-11 15:47:00 (CST-6)
Location: ROBERTS
Magnitude: 55.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Multiple power lines were blown down along Route 54 between Gibson City and Thawville.

Flash Flood in IROQUOIS, ILLINOIS
From 22-MAY-11 15:52:00 to 22-MAY-11 18:00:00 (CST-6)
Location: WATSEKA
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Heavy rain fell across Watseka causing streets to flood.  Many intersections were barricaded and closed due to flooding.  One spotter reported that 1.61 inches of rain fell in 75 minutes.  An emergency manager reported a storm total of 2.12 inches.  A co-op observer reported 2.17 inches.

Thunderstorm Wind in IROQUOIS, ILLINOIS
From 22-MAY-11 15:55:00 to 22-MAY-11 15:55:00 (CST-6)
Location: CISSNA PARK
Magnitude: 55.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Wind gusts were estimated to 63 mph.

Thunderstorm Wind in IROQUOIS, ILLINOIS
From 22-MAY-11 15:47:00 to 22-MAY-11 15:47:00 (CST-6)
Location: RIDGEVILLE
Magnitude: 55.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Multiple power lines were blown down along Route 54 Between Gilman and Thawville.

Lightning in COOK, ILLINOIS
From 22-MAY-11 21:10:00 to 22-MAY-11 21:10:00 (CST-6)
Location: TECHNY
Property damage: 250.00K
Crop damage: 0.00K
Reported by: Newspaper

Lightning struck a four story apartment building on Summit Drive causing damage to the roof and attic.

Lightning in WILL, ILLINOIS
From 22-MAY-11 15:02:00 to 22-MAY-11 15:02:00 (CST-6)
Location: BEECHER
Property damage: 300.00K
Crop damage: 0.00K
Reported by: Newspaper

A house near the intersection of South Ashland Avenue and Peotone-Beecher Road caught on fire after being struck by lightning.  The roof and second story were completely destroyed by the fire and the first floor was destroyed by water damage.

Tornado in OGLE, ILLINOIS
From 22-MAY-11 17:28:00 to 22-MAY-11 17:31:00 (CST-6)
Location: POLO RADIO RANCH ARP
Tornado F-scale: EF1
Property damage: 50.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

The tornado touched down south of unincorporated Polo, just south of the intersection of Union Road and Judson Road.  The roof of a cattle shed was blown off along Judson Road.  Several beef cattle were in the shed and one was injured severely enough it had to be euthanized.  A power pole on the east side of Union Road was blown down, leaning over the road toward the west.  At this point the tornado was rated low end EF1 with winds estimated at 85-90 mph.  The tornado widened slightly as it progressed to the east along Judson Road, and uprooted a 20 inch diameter fir tree.  At this point the tornado was still at EF1 strength, and there were branches down.  The tornado then moved east and its width widened to its maximum 200 yards.  There was roof damage to sheet metal roofing on 4 buildings and a wood outbuilding that was left leaning over by the tornado.  In this area several 2x4���s were speared into the ground from different directions and insulation was plastered on the east and northeast face of buildings.  Another property just to the northeast of this point experienced six 16 inch diameter Norway Spruce trees snapped off, and a new wood power pole was snapped in half.  It was here where the tornado reached its maximum intensity with winds at 100 mph.  The tornado continued to the east maintaining its intensity (EF1 strength) another quarter mile to the east where a grain bin was ripped off its foundation and a portion of the roof blown off to the north up against a fence.  After this the winds weakened as the tornado lifted.  A couple of additional grain bins were blown over, small branches snapped off, and shingles blown off roofs.  Winds were estimated at 70-80 mph.  The tornado lifted at 10506 Judson Road at Bailey Road.

Hail in WINNEBAGO, ILLINOIS
From 22-MAY-11 17:50:00 to 22-MAY-11 18:02:00 (CST-6)
Location: ROCKFORD
Magnitude: 1.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Numerous reports of large hail up to walnut size were received from the city of Rockford as a severe line of thunderstorms moved across the city.  Some of the specific reports include: quarter size hail approximately four miles northwest of Rockford; quarter size hail at the intersection of Huffman Boulevard and Auburn street; penny to nickel size hail just east of downtown Rockford; quarter size hail at the intersection of Alpine Road and Harrison Avenue; half dollar size hail at the intersection of John Street and North Court Street.

Tornado in WINNEBAGO, ILLINOIS
From 22-MAY-11 17:37:00 to 22-MAY-11 17:54:00 (CST-6)
Location: SEWARD
Tornado F-scale: EF1
Property damage: 100.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

This is a continuation of a tornado that started in Ogle County and crossed into Winnebago County on East Montague Road near South Conger Road.  The path was nearly continuous briefly lifting near Kelly Road east of just Alworth Road, then continuing again into the west side of Machesney Park past the Kennedy Middle School which had part of its roof blown off.  A persistent path of damage was observed until the end of the tornado���s life when damage became sporadic.  Several damage indicators indicating a persistent EF1 rating were observed throughout the tornado���s path.  There were numerous softwood trees snapped or uprooted, some up to 24-30 inches in diameter.  A few hardwood trees up to 18 inches in diameter were also snapped. Many tree limbs were also downed.  Structural damage included several collapsed outbuildings, damaged siding and fascia to homes, and shingles blown off roofs.  Debris in numerous locations was deposited downstream from its origin, sometimes up to 400 yards.  All of the damage suggested winds from 90-110 mph.

Thunderstorm Wind in WINNEBAGO, ILLINOIS
From 22-MAY-11 17:49:00 to 22-MAY-11 17:56:00 (CST-6)
Location: (RFD)GTR ROCKFORD AR
Magnitude: 65.00 EG
Property damage: 50.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Several high wind and wind damage reports were received across eastern and southeastern Rockford as a line of severe storms moves through.  Specific reports include estimated 70 mph gusts near Alpine Road and Harrison Avenue and estimated 75 mph gusts near Interstate 90 and Highway 20.  One person was injured on Crosby Street on the near east side of Rockford when a tree fell onto a house.  A large tree fell onto a car on Antelope Drive and destroyed the car.  Another tree fell onto a car on Fairview Avenue.  A pharmacy on Main street lost part of its roof and part of a wall was damaged.  Tree limbs and power lines were blown down in many areas.

Thunderstorm Wind in WINNEBAGO, ILLINOIS
From 22-MAY-11 17:55:00 to 22-MAY-11 17:55:00 (CST-6)
Location: NEW MILFORD
Magnitude: 60.00 EG
Property damage: 50.00K
Crop damage: 0.00K
Reported by: Newspaper

A large tree was blown down onto a building near Route 251 and New Milford School Road.  A nearby building suffered significant damage when a 50 foot ash tree fell onto the building.

Thunderstorm Wind in WINNEBAGO, ILLINOIS
From 22-MAY-11 17:43:00 to 22-MAY-11 17:50:00 (CST-6)
Location: WINNEBAGO
Magnitude: 60.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Numerous one foot diameter trees were reported down in and around Winnebago.

Tornado in WINNEBAGO, ILLINOIS
From 22-MAY-11 17:59:00 to 22-MAY-11 18:01:00 (CST-6)
Location: SOUTH BELOIT
Tornado F-scale: EF1
Property damage: 15.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

A brief tornado touched down in the Rockton area between Route 251 and Interstate 90, just north of Rockton Road.  Damage was observed around the Roscoe Fire Station, where a large garage door was blown in.  Winds were estimated to be as high as 90-100 mph.

Tornado in WINNEBAGO, ILLINOIS
From 22-MAY-11 17:55:00 to 22-MAY-11 17:58:00 (CST-6)
Location: WEMPLETON
Tornado F-scale: EF1
Reported by: NWS Storm Survey

A tornado touched down just west of Latham Park.  A pocket of intense and concentrated damage embedded in a more widespread area of straight-line wind damage was classified as tornadic with winds estimated at 90 to 100 mph.  No structural damage was observed except where trees fell on houses.

Thunderstorm Wind in BOONE, ILLINOIS
From 22-MAY-11 18:04:00 to 22-MAY-11 18:10:00 (CST-6)
Location: CALEDONIA
Magnitude: 55.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Numerous trees and wires were blown down across northern portions of Boone County near Poplar Grove.

Thunderstorm Wind in MCHENRY, ILLINOIS
From 22-MAY-11 18:25:00 to 22-MAY-11 18:25:00 (CST-6)
Location: HEBRON ARPT
Magnitude: 60.00 EG
Property damage: 1.00K
Crop damage: 0.00K
Reported by: Trained Spotter

At least 8 ten inch diameter trees were uprooted in Hebron.  Power poles were blown down along Route 47 approximately 3 miles south of Hebron.  A fence was downed at one of the schools.

Thunderstorm Wind in KANKAKEE, ILLINOIS
From 22-MAY-11 14:40:00 to 22-MAY-11 14:40:00 (CST-6)
Location: WEST KANKAKEE
Magnitude: 50.00 EG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Trained Spotter

On the west side of Kankakee, several 4 to 6 inch diameter tree branches were reported down.  A ten inch diameter tree was down in Small Memorial Park. A large branch fell onto a van on West Hawkins Street.

Hail in WILL, ILLINOIS
From 22-MAY-11 14:53:00 to 22-MAY-11 15:00:00 (CST-6)
Location: BEECHER
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Up to golf ball size hail was reported near the town of Beecher.  Specific reports include golf ball and half dollar size hail approximately one and two miles south of Beecher, respectively, on Illinois Route 1.  Half dollar size hail was also reported near the intersection of Ashland Avenue and Peotone-Beecher Road.

Thunderstorm Wind in IROQUOIS, ILLINOIS
From 22-MAY-11 15:34:00 to 22-MAY-11 15:34:00 (CST-6)
Location: CRESCENT CITY
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Wind gusts were estimated to 60 mph.

Hail in COOK, ILLINOIS
From 22-MAY-11 14:07:00 to 22-MAY-11 14:09:00 (CST-6)
Location: GOLDEN ACRES
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Quarter size hail was reported on East Seegers Road.

Tornado in OGLE, ILLINOIS
From 22-MAY-11 17:25:00 to 22-MAY-11 17:37:00 (CST-6)
Location: FORRESTON
Tornado F-scale: EF1
Property damage: 50.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

A tornado touched down just east of Forreston, on Columbine Road near Illinois Route 72 in Ogle County.  The tornado continued to the northeast with a near continuous path into Winnebago County.  A mobile home lost part of its roof with walls partially collapsed in Adeline.  Another double wide home lost a portion of its roof on Leaf River Road at Myrtle road.  A couple of utility poles were also snapped or leaning over.  The tornado crossed into Winnebago County on East Montague Road near South Conger Road.

Thunderstorm Wind in MCHENRY, ILLINOIS
From 22-MAY-11 18:29:00 to 22-MAY-11 18:29:00 (CST-6)
Location: RICHMOND
Magnitude: 60.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Several trees were uprooted in Richmond.  Route 12 was blocked by a fallen tree just east of Route 31.