Over the space of about four hours from late on April 19 into the early morning hours of April 20, 2011, a squall line brought a historic number of tornadoes to southern Indiana and central Kentucky.  Storm surveys over the subsequent few days uncovered 25 tornadoes -the most ever recorded here in one outbreak.  On the 19th, low pressure had organized over southeast Kansas with a stationary front reaching east into the central Appalachians.  Plentiful moisture streamed northward from the Gulf of Mexico ahead of the system.  The Kansas low moved along the front and swung a cold front eastward.  Instability, strong upper level winds, and significant changes in wind speed and direction with height helped cause a large squall line to develop ahead of the low and its cold front.  The squall line caused severe weather from the eastern Great Lakes to the Red River Valley.  Over two dozen tornadoes spun up along the line as it crossed southern Indiana and central Kentucky.  Despite the numerous twisters and the fact that they struck during the overnight hours, there were no fatalities or injuries.

Hail in WARREN, KENTUCKY
From 20-APR-11 00:35:00 to 20-APR-11 00:35:00 (CST-6)
Location: MEMPHIS JCT
Magnitude: 1.00 
Reported by: Trained Spotter

Up to quarter size hail was reported in the Memphis Junction area.

Thunderstorm Wind in SHELBY, KENTUCKY
From 20-APR-11 00:39:00 to 20-APR-11 00:39:00 (EST-5)
Location: WADDY
Magnitude: 52.00 EG
Reported by: Trained Spotter

Trees were blown down.

Hail in GRAYSON, KENTUCKY
From 19-APR-11 23:03:00 to 19-APR-11 23:03:00 (CST-6)
Location: LEITCHFIELD
Magnitude: 0.88 
Reported by: Trained Spotter

Thunderstorm Wind in SIMPSON, KENTUCKY
From 19-APR-11 23:15:00 to 19-APR-11 23:15:00 (CST-6)
Location: MIDDLETON
Magnitude: 87.00 EG
Reported by: NWS Storm Survey

An NWS storm survey found four damaged barns, as well as one destroyed barn.  A lot of trees were blown down as well.  Winds were estimated to be 95 to 100 mph.

Hail in WARREN, KENTUCKY
From 20-APR-11 00:43:00 to 20-APR-11 00:43:00 (CST-6)
Location: PLANO
Magnitude: 1.00 
Reported by: Trained Spotter

Thunderstorm Wind in LARUE, KENTUCKY
From 20-APR-11 00:44:00 to 20-APR-11 00:44:00 (EST-5)
Location: MAGNOLIA
Magnitude: 52.00 EG
Reported by: Trained Spotter

Trees were blown down.

Thunderstorm Wind in LOGAN, KENTUCKY
From 19-APR-11 23:15:00 to 19-APR-11 23:15:00 (CST-6)
Location: HALLS STORE
Magnitude: 87.00 EG
Reported by: NWS Storm Survey

An NWS storm survey found both structural and tree damage.  Winds were estimated to be 100 mph.

Thunderstorm Wind in JEFFERSON, KENTUCKY
From 19-APR-11 23:15:00 to 19-APR-11 23:15:00 (EST-5)
Location: HARRODS CREEK
Magnitude: 52.00 EG
Reported by: NWS Employee

A tree was blown down and siding blown off a house near the Fincastle area.

Hail in WARREN, KENTUCKY
From 20-APR-11 00:45:00 to 20-APR-11 00:45:00 (CST-6)
Location: BOWLING GREEN
Magnitude: 1.00 
Reported by: Broadcast Media

Thunderstorm Wind in SCOTT, KENTUCKY
From 20-APR-11 00:48:00 to 20-APR-11 00:48:00 (EST-5)
Location: GEORGETOWN
Magnitude: 52.00 EG
Reported by: Broadcast Media

Trees were down on Paris Pike and on Newtown Pike near county fire number 4.

Thunderstorm Wind in MEADE, KENTUCKY
From 19-APR-11 23:17:00 to 19-APR-11 23:17:00 (EST-5)
Location: BRANDENBURG
Magnitude: 52.00 EG
Reported by: Trained Spotter

Trees were blown down.

Thunderstorm Wind in EDMONSON, KENTUCKY
From 19-APR-11 23:30:00 to 19-APR-11 23:30:00 (CST-6)
Location: BROWNSVILLE
Magnitude: 52.00 MG
Reported by: Trained Spotter

A trained spotter reported wind gusts to 60 mph.

Thunderstorm Wind in BARREN, KENTUCKY
From 20-APR-11 00:50:00 to 20-APR-11 00:50:00 (CST-6)
Location: GLASGOW
Magnitude: 60.00 MG
Reported by: AWOS

The AWOS at Glasgow Municipal Airport, Moore Field, measured a wind gust of 69 mph.

Thunderstorm Wind in EDMONSON, KENTUCKY
From 19-APR-11 23:30:00 to 19-APR-11 23:30:00 (CST-6)
Location: BROWNSVILLE
Magnitude: 52.00 MG
Reported by: Trained Spotter

A trained spotter reported wind gusts to 60 mph.

Thunderstorm Wind in BARREN, KENTUCKY
From 20-APR-11 00:50:00 to 20-APR-11 00:50:00 (CST-6)
Location: GLASGOW
Magnitude: 61.00 EG
Reported by: Law Enforcement

Trees an power lines were down countywide.  A tree was blocking Cherry St. in the town of Glasgow.

Thunderstorm Wind in HENRY, KENTUCKY
From 19-APR-11 23:30:00 to 19-APR-11 23:30:00 (EST-5)
Location: NEW CASTLE
Magnitude: 52.00 EG
Reported by: Law Enforcement

Trees were blown down county-wide.

Thunderstorm Wind in ALLEN, KENTUCKY
From 20-APR-11 00:52:00 to 20-APR-11 00:52:00 (CST-6)
Location: HOLLAND
Magnitude: 56.00 EG
Reported by: Law Enforcement

Trees were reported down across southern Allen county.  A tree was blocking the road at the 800 block of Holland Rd.  A tree also blocked the intersections of Walkers Chapel and Pleasant Ridge Roads, as well as Highland Church and Bandy Roads.

Thunderstorm Wind in HARDIN, KENTUCKY
From 19-APR-11 23:52:00 to 19-APR-11 23:52:00 (EST-5)
Location: ELIZABETH TOWN
Magnitude: 52.00 EG
Reported by: Law Enforcement

Trees and power lines were reported down.

Thunderstorm Wind in SHELBY, KENTUCKY
From 20-APR-11 00:04:00 to 20-APR-11 00:04:00 (EST-5)
Location: SIMPSONVILLE
Magnitude: 52.00 EG
Reported by: Emergency Manager

The Shelby county emergency manager reported wind gusts to 60 mph.

Thunderstorm Wind in EDMONSON, KENTUCKY
From 20-APR-11 00:57:00 to 20-APR-11 00:57:00 (CST-6)
Location: BROWNSVILLE
Magnitude: 52.00 EG
Reported by: Law Enforcement

Trees were down on homes in the southern part of the county.

Thunderstorm Wind in JEFFERSON, KENTUCKY
From 19-APR-11 23:30:00 to 19-APR-11 23:30:00 (EST-5)
Location: AUDUBON PARK
Magnitude: 52.00 EG
Reported by: Law Enforcement

The city of Louisville reported numerous trees down throughout the metro area.

Hail in BUTLER, KENTUCKY
From 19-APR-11 23:36:00 to 19-APR-11 23:36:00 (CST-6)
Location: MORGANTOWN
Magnitude: 0.88 
Reported by: Trained Spotter

Thunderstorm Wind in HARRISON, KENTUCKY
From 20-APR-11 01:06:00 to 20-APR-11 01:06:00 (EST-5)
Location: GARNETT
Magnitude: 52.00 EG
Reported by: Emergency Manager

Several trees were blown down just north of Breckinridge.

Thunderstorm Wind in METCALFE, KENTUCKY
From 20-APR-11 01:15:00 to 20-APR-11 01:15:00 (CST-6)
Location: EDMONTON
Magnitude: 52.00 EG
Reported by: Law Enforcement

Trees were blown down.

Hail in GREEN, KENTUCKY
From 20-APR-11 01:00:00 to 20-APR-11 01:00:00 (CST-6)
Location: WEBBS XRDS
Magnitude: 1.00 
Reported by: Law Enforcement

Flash Flood in OHIO, KENTUCKY
From 20-APR-11 01:00:00 to 20-APR-11 01:00:00 (CST-6)
Location: HARTFORD
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Roads were flooded and a few were impassable west of Beaver Dam.

Thunderstorm Wind in BULLITT, KENTUCKY
From 19-APR-11 23:39:00 to 19-APR-11 23:39:00 (EST-5)
Location: BROOKS
Magnitude: 52.00 MG
Reported by: Trained Spotter

A trained spotter reported wind gusts to 60 mph.

Hail in HARDIN, KENTUCKY
From 20-APR-11 00:04:00 to 20-APR-11 00:04:00 (EST-5)
Location: ELIZABETH TOWN
Magnitude: 0.88 
Reported by: Trained Spotter

Thunderstorm Wind in JEFFERSON, KENTUCKY
From 20-APR-11 00:05:00 to 20-APR-11 00:05:00 (EST-5)
Location: PROSPECT
Magnitude: 52.00 EG
Reported by: Trained Spotter

Trees and power lines were reported down.

Thunderstorm Wind in NELSON, KENTUCKY
From 20-APR-11 00:06:00 to 20-APR-11 00:06:00 (EST-5)
Location: BARDSTOWN
Magnitude: 52.00 EG
Reported by: Law Enforcement

Trees were down in the city of Bardstown.

Thunderstorm Wind in LARUE, KENTUCKY
From 20-APR-11 00:10:00 to 20-APR-11 00:10:00 (EST-5)
Location: JERICHO
Magnitude: 61.00 EG
Reported by: NWS Employee

A newly constructed metal garage work building was destroyed.

Thunderstorm Wind in LOGAN, KENTUCKY
From 20-APR-11 00:21:00 to 20-APR-11 00:21:00 (CST-6)
Location: JERICO
Magnitude: 52.00 EG
Reported by: Law Enforcement

A tree was down on Hwy. 431.

Thunderstorm Wind in OLDHAM, KENTUCKY
From 19-APR-11 23:46:00 to 19-APR-11 23:46:00 (EST-5)
Location: GLENARM
Magnitude: 61.00 EG
Reported by: NWS Storm Survey

An NWS storm survey confirmed straight-line wind damage with winds estimated to be 60-70 mph.  There was mainly tree damage with some power lines down.

Thunderstorm Wind in FAYETTE, KENTUCKY
From 20-APR-11 01:04:00 to 20-APR-11 01:04:00 (EST-5)
Location: LEXINGTON
Magnitude: 52.00 EG
Reported by: Law Enforcement

A tree was down at the intersection of McDowell and Fontaine Roads.

Thunderstorm Wind in SCOTT, KENTUCKY
From 20-APR-11 01:17:00 to 20-APR-11 01:17:00 (EST-5)
Location: GEORGETOWN
Magnitude: 52.00 EG
Reported by: Law Enforcement

Four trees and a power line were blown down.  A trampoline was blown into a roadway.

Hail in ADAIR, KENTUCKY
From 20-APR-11 01:25:00 to 20-APR-11 01:25:00 (CST-6)
Location: MILLTOWN
Magnitude: 1.00 
Reported by: Emergency Manager

Quarter sized hail was reported in Milltown, just west of Columbia.  Multiple trees were also down and power outages were reported in Columbia.

Thunderstorm Wind in MADISON, KENTUCKY
From 20-APR-11 01:35:00 to 20-APR-11 01:35:00 (EST-5)
Location: BYBEE
Magnitude: 50.00 MG
Reported by: Fire Department/Rescue

The fire department reported a measured gust of 58 mph.

Thunderstorm Wind in MADISON, KENTUCKY
From 20-APR-11 01:38:00 to 20-APR-11 01:38:00 (EST-5)
Location: MIDDLETOWN
Magnitude: 52.00 EG
Reported by: Emergency Manager

A tree was blown down in Berea.  Power lines were also reported down.

Thunderstorm Wind in WASHINGTON, KENTUCKY
From 20-APR-11 00:23:00 to 20-APR-11 00:23:00 (EST-5)
Location: ST CATHERINE
Magnitude: 52.00 EG
Reported by: Emergency Manager

A tree was down and blocking Hwy. 55.

Thunderstorm Wind in BOURBON, KENTUCKY
From 20-APR-11 01:39:00 to 20-APR-11 01:39:00 (EST-5)
Location: PARIS
Magnitude: 52.00 EG
Reported by: Law Enforcement

A tree was down on Georgetown Rd.

Thunderstorm Wind in FRANKLIN, KENTUCKY
From 20-APR-11 00:26:00 to 20-APR-11 00:26:00 (EST-5)
Location: FRANKFT CPTL CITY AR
Magnitude: 59.00 MG
Reported by: ASOS

The ASOS at Capital City Airport in Frankfort measured a gust of 68 mph.

Thunderstorm Wind in JESSAMINE, KENTUCKY
From 20-APR-11 01:05:00 to 20-APR-11 01:05:00 (EST-5)
Location: NICHOLASVILLE
Magnitude: 52.00 EG
Reported by: Broadcast Media

A light pole was blown down near the north junction of US 27 in Nicholasville.  Trees were also blown down at Allen Dr.

Thunderstorm Wind in BULLITT, KENTUCKY
From 19-APR-11 23:49:00 to 19-APR-11 23:49:00 (EST-5)
Location: BROOKS
Magnitude: 52.00 EG
Reported by: Trained Spotter

Numerous trees were blown down.

Thunderstorm Wind in OLDHAM, KENTUCKY
From 19-APR-11 23:50:00 to 19-APR-11 23:50:00 (EST-5)
Location: LA GRANGE
Magnitude: 61.00 EG
Reported by: NWS Storm Survey

An NWS storm survey confirmed straight line wind damage with winds estimated at 60-70 mph.  There was mainly tree damage with some power lines down.

Thunderstorm Wind in RUSSELL, KENTUCKY
From 20-APR-11 01:42:00 to 20-APR-11 01:42:00 (CST-6)
Location: RUSSELL SPGS
Magnitude: 52.00 EG
Reported by: Broadcast Media

Trees were blown down.

Thunderstorm Wind in FRANKLIN, KENTUCKY
From 20-APR-11 00:27:00 to 20-APR-11 00:27:00 (EST-5)
Location: FRANKFORT
Magnitude: 56.00 EG
Reported by: Emergency Manager

Capital Ave. was closed by a downed tree.

Tornado in BRECKINRIDGE, KENTUCKY
From 19-APR-11 21:54:00 to 19-APR-11 21:58:00 (CST-6)
Location: MYSTIC
Tornado F-scale: EF0
Reported by: NWS Storm Survey

A NWS storm survey confirmed an EF-0 tornado with wind speeds estimated to be 65-80 mph touched down in Breckinridge county.  The tornado lifted in several locations along the 11 mi. path, with the greatest width of 50 yards.  The tornado continued into Meade county where it last lifted 4 miles west of Brandenburg. In Breckinridge county the damage was mainly to trees that were snapped or uprooted.

Tornado in MEADE, KENTUCKY
From 19-APR-11 22:58:00 to 19-APR-11 23:04:00 (EST-5)
Location: PAYNEVILLE
Tornado F-scale: EF0
Reported by: NWS Storm Survey

A NWS storm survey confirmed an EF-0 tornado with wind speeds estimated to be 65-80 mph touched down in Breckinridge county. The tornado lifted in several locations along the 11 mi. path, with the greatest width of 50 yards. The tornado continued into Meade county where it last lifted 4 miles west of Brandenburg. The worst damage with this tornado occurred at a house in an elevated location along Sirocco Road in Meade County. At that location a carport that was attached to the house blew across the field behind it. Trees were snapped or uprooted, a barn door was blown in, and shingles were blown off of the roof of another nearby house.

Thunderstorm Wind in HANCOCK, KENTUCKY
From 19-APR-11 22:03:00 to 19-APR-11 22:03:00 (CST-6)
Location: LEWISPORT
Magnitude: 57.00 MG
Reported by: Mesonet

The Kentucky mesonet site in Hancock county measured a wind gust of 66 mph.

Thunderstorm Wind in BRECKINRIDGE, KENTUCKY
From 19-APR-11 22:07:00 to 19-APR-11 22:07:00 (CST-6)
Location: HARDINSBURG ARPT
Magnitude: 52.00 EG
Reported by: Law Enforcement

Trees were down west of Hardinsburg.

Thunderstorm Wind in OLDHAM, KENTUCKY
From 20-APR-11 00:29:00 to 20-APR-11 00:29:00 (EST-5)
Location: LA GRANGE
Magnitude: 56.00 EG
Reported by: Trained Spotter

Trees and power lines were down in the city.

Thunderstorm Wind in FRANKLIN, KENTUCKY
From 20-APR-11 00:29:00 to 20-APR-11 00:29:00 (EST-5)
Location: FRANKFORT
Magnitude: 56.00 EG
Reported by: Law Enforcement

Trees were down on roadways throughout the city.  A sign was blown into a window at a business in the 800 block of Louisville Rd.

Tornado in OLDHAM, KENTUCKY
From 19-APR-11 23:49:00 to 19-APR-11 23:50:00 (EST-5)
Location: LA GRANGE
Tornado F-scale: EF1
Reported by: NWS Storm Survey

An NWS Storm Survey confirmed an EF-1 tornado with winds estimated to be 90 mph.  The path length was approximately a quarter of a mile with a width of 80 yards.  A barn was destroyed and large hardwood trees were snapped 30 feet off the ground.  It later damaged the roof of a house and another barn.

Thunderstorm Wind in OHIO, KENTUCKY
From 19-APR-11 22:14:00 to 19-APR-11 22:14:00 (CST-6)
Location: DEANEFIELD
Magnitude: 51.00 MG
Reported by: Trained Spotter

A trained spotter reported a measured gust of 59 mph.

Thunderstorm Wind in BRECKINRIDGE, KENTUCKY
From 19-APR-11 22:12:00 to 19-APR-11 22:12:00 (CST-6)
Location: HARDINSBURG ARPT
Magnitude: 52.00 MG
Reported by: Trained Spotter

A trained spotter reported a measured gust of 60 mph as well as trees down.

Thunderstorm Wind in SIMPSON, KENTUCKY
From 20-APR-11 00:30:00 to 20-APR-11 00:30:00 (CST-6)
Location: FRANKLIN
Magnitude: 56.00 EG
Reported by: Trained Spotter

Trees were snapped and downed.

Hail in EDMONSON, KENTUCKY
From 20-APR-11 00:30:00 to 20-APR-11 00:30:00 (CST-6)
Location: BROWNSVILLE
Magnitude: 1.00 
Reported by: Law Enforcement

Thunderstorm Wind in BRECKINRIDGE, KENTUCKY
From 19-APR-11 22:17:00 to 19-APR-11 22:17:00 (CST-6)
Location: WEBSTER
Magnitude: 52.00 EG
Reported by: Trained Spotter

Trees were blown down across highway 333.

Thunderstorm Wind in OHIO, KENTUCKY
From 19-APR-11 22:21:00 to 19-APR-11 22:21:00 (CST-6)
Location: OLATON
Magnitude: 52.00 EG
Reported by: Trained Spotter

Trees and power lines were down.

Tornado in SIMPSON, KENTUCKY
From 20-APR-11 00:30:00 to 20-APR-11 00:33:00 (CST-6)
Location: FRANKLIN WHAK ARPT
Tornado F-scale: EF1
Reported by: NWS Storm Survey

An NWS Storm Survey confirmed an EF-1 tornado with estimated wind speeds of 90-95 mph. When the tornado touched down it destroyed a barn and threw debris about a quarter mile. The tornado then damaged the roof of another barn and uprooted or snapped at least a hundred trees. The tornado lifted near the intersection of US 31W and Ogles Street.

Tornado in SCOTT, KENTUCKY
From 20-APR-11 00:54:00 to 20-APR-11 00:55:00 (EST-5)
Location: NEWTOWN
Tornado F-scale: EF1
Property damage: 35.00K
Reported by: NWS Storm Survey

An NWS storm survey confirmed an EF-1 tornado with winds up to 95 mph touched down in an open field northeast of Georgetown and moved quickly east, overturning a tied-down trailer and destroying or damaging several outbuildings. After passing over Leesburg Road, the tornado buckled the brick garage wall of a well built home and snapped several tres along a fence line before dissipating.

Thunderstorm Wind in FRANKLIN, KENTUCKY
From 20-APR-11 00:30:00 to 20-APR-11 00:30:00 (EST-5)
Location: FRANKFORT
Magnitude: 56.00 EG
Reported by: Emergency Manager

Multiple trees were downed countywide.  Power outages were reported both east and west of Frankfort.

Thunderstorm Wind in WARREN, KENTUCKY
From 20-APR-11 00:35:00 to 20-APR-11 00:35:00 (CST-6)
Location: BOWLING GREEN
Magnitude: 56.00 EG
Reported by: Law Enforcement

Trees were down- some on power lines.  Power lines were also down and trees were blocking roads.

Thunderstorm Wind in GRAYSON, KENTUCKY
From 19-APR-11 22:44:00 to 19-APR-11 22:44:00 (CST-6)
Location: LEITCHFIELD
Magnitude: 52.00 MG
Reported by: Law Enforcement

Law enforcement reported a gust to 60 mph.

Thunderstorm Wind in GRAYSON, KENTUCKY
From 19-APR-11 22:51:00 to 19-APR-11 22:51:00 (CST-6)
Location: LEITCHFIELD
Magnitude: 52.00 EG
Reported by: Trained Spotter

Trees were blown down.

Tornado in FRANKLIN, KENTUCKY
From 20-APR-11 00:28:00 to 20-APR-11 00:33:00 (EST-5)
Location: FRANKFT CPTL CITY AR
Tornado F-scale: EF0
Reported by: NWS Storm Survey

An NWS Storm Survey confirmed an EF-0 tornado with estimated wind speeds of 70 mph.  Several trees were damaged and shingles were knocked off of houses.  The most intense damage was found near the Frankfort cemetery and the Frankfort capitol building.