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.

Tornado in DUBOIS, INDIANA
From 19-APR-11 22:22:00 to 19-APR-11 22:25:00 (EST-5)
Location: IRELAND
Tornado F-scale: EF1
Reported by: NWS Storm Survey

An NWS storm survey confirmed an EF-1 tornado with wind speed estimated at 100-105 mph north of Ireland. A well-constructed 75-foot tall grain silo had the top 40 feet sheared off.  A 40ft x 50ft outbuilding in the vicinity of the silo was destroyed, its siding thrown 500 yards downwind. In addition to the tornado, straight-line wind damage was observed. Two hog buildings were destroyed and a grain silo was shifted on its foundation.

Tornado in DUBOIS, INDIANA
From 19-APR-11 22:25:00 to 19-APR-11 22:27:00 (EST-5)
Location: HAYSVILLE
Tornado F-scale: EF0
Reported by: NWS Storm Survey

An EF-0 tornado with winds speeds up to 80 mph was confirmed near Haysville. At the beginning point of this tornado a few small trees, some dead, were blown over and branches were blown off of some of the trees. Several trees were blown over in Haysville. The most intense damage occurred as the tornado lifted east of Haysville in the woods along Indiana 56. At that point several trees up to two feet in diameter were blown down.

Thunderstorm Wind in DUBOIS, INDIANA
From 19-APR-11 22:25:00 to 19-APR-11 22:25:00 (EST-5)
Location: JASPER
Magnitude: 58.00 MG
Reported by: Mesonet

The gust was measured at the Jasper Middle School.

Thunderstorm Wind in DUBOIS, INDIANA
From 19-APR-11 22:34:00 to 19-APR-11 22:34:00 (EST-5)
Location: JASPER
Magnitude: 56.00 EG
Reported by: Law Enforcement

Numerous trees and power lines were down across the city.

Tornado in DUBOIS, INDIANA
From 19-APR-11 22:26:00 to 19-APR-11 22:27:00 (EST-5)
Location: ST MARKS
Tornado F-scale: EF1
Reported by: NWS Storm Survey

An NWS storm survey confirmed an EF-1 tornado with wind speeds estimated to be 95 mph near Saint Anthony.  Along the path, hardwood trees were snapped and uprooted.  A residence north of Indiana 64 was damaged.

Tornado in DUBOIS, INDIANA
From 19-APR-11 22:26:00 to 19-APR-11 22:29:00 (EST-5)
Location: BRETZVILLE
Tornado F-scale: EF2
Reported by: NWS Storm Survey

An NWS storm survey confirmed an EF-2 tornado with wind speeds of 115-120 mph touched down near Bretzville.  It then tracked to the northeast, ending north of Saint Anthony. A large number of trees were snapped and uprooted. Several barns and outbuildings were destroyed along the path as well.

Thunderstorm Wind in DUBOIS, INDIANA
From 19-APR-11 22:35:00 to 19-APR-11 22:35:00 (EST-5)
Location: JASPER
Magnitude: 61.00 EG
Reported by: Law Enforcement

Overturned mobile homes were reported in the city of Jasper.

Thunderstorm Wind in CRAWFORD, INDIANA
From 19-APR-11 22:38:00 to 19-APR-11 22:38:00 (EST-5)
Location: TASWELL
Magnitude: 56.00 MG
Reported by: Trained Spotter

A trained spotter reported a measured gust of 64 mph.

Tornado in ORANGE, INDIANA
From 19-APR-11 22:39:00 to 19-APR-11 22:40:00 (EST-5)
Location: ROLAND
Tornado F-scale: EF2
Reported by: NWS Storm Survey

An NWS storm survey confirmed an EF-2 tornado near Roland with estimated wind speeds of up to 115 mph. Numerous trees were uprooted and snapped in a convergent pattern. In one concentrated spot two dozen trees were snapped off. A house had its windows blown in on its southwest side. A well constructed cabin lost some shingles. A very well constructed large barn lost its metal roof, which was wrapped into tree tops 200 yards downwind. A wood outbuilding was destroyed. Straight line winds increased the total damage path width to about 0.6 mile.

Thunderstorm Wind in PERRY, INDIANA
From 19-APR-11 22:43:00 to 19-APR-11 22:43:00 (EST-5)
Location: TROY
Magnitude: 56.00 EG
Reported by: Law Enforcement

Trees were reported down.

Tornado in ORANGE, INDIANA
From 19-APR-11 22:40:00 to 19-APR-11 22:41:00 (EST-5)
Location: NEWTON STEWART
Tornado F-scale: EF1
Reported by: NWS Storm Survey

An NWS storm survey confirmed an EF1 tornado with estimated wind speed up to 100 mph. This tornado touched down just west of Tony's Marina near Indiana 145. Trees were uprooted and snapped. A large metal barn with cinder block walls was destroyed. The tornado then crossed Route 145 and moved in to Tony's Marina.  Three metal outbuildings were damaged or destroyed. One of the buildings had its doors blown in...another had its metal roof peeled back...and the third was leveled and blown 300 yards downwind. Trees were uprooted in a convergent pattern.  Some trees fell on power poles, causing the poles to snap.  A pontoon boat was flipped over.

Thunderstorm Wind in PERRY, INDIANA
From 19-APR-11 22:49:00 to 19-APR-11 22:49:00 (EST-5)
Location: TELL CITY
Magnitude: 56.00 EG
Reported by: Law Enforcement

Trees and power lines were blown down across the city.

Tornado in ORANGE, INDIANA
From 19-APR-11 22:40:00 to 19-APR-11 22:41:00 (EST-5)
Location: GREENBRIER
Tornado F-scale: EF1
Reported by: NWS Storm Survey

An NWS storm survey confirmed an EF-1 tornado with wind speeds up to 110 mph.  This tornado touched down near the intersection of Indiana 145 and Base Line Road, where it destroyed a metal-roofed barn. Trees were uprooted and snapped. At a house on Base Line Road the front porch was ripped off and deposited in the back yard. A cluster of large, tall evergreens was snapped off and strewn chaotically in all directions.

Tornado in ORANGE, INDIANA
From 19-APR-11 22:47:00 to 19-APR-11 22:48:00 (EST-5)
Location: YOUNGS CREEK
Tornado F-scale: EF0
Reported by: NWS Storm Survey

An NWS storm survey confirmed an EF-0 tornado with estimated wind speeds up to 80 mph. Along the path, several trees were uprooted along W CR390S. A couple of trees were snapped. A metal roof was peeled off of a small outbuilding.

Thunderstorm Wind in ORANGE, INDIANA
From 19-APR-11 22:49:00 to 19-APR-11 22:49:00 (EST-5)
Location: CHAMBERSBURG
Magnitude: 78.00 EG
Reported by: NWS Storm Survey

An NWS storm survey confirmed straight line winds uprooted trees and blew half a metal roof off a house.  Winds were estimated to be 90 mph.

Thunderstorm Wind in ORANGE, INDIANA
From 19-APR-11 22:50:00 to 19-APR-11 22:50:00 (EST-5)
Location: PAOLI
Magnitude: 52.00 MG
Reported by: Trained Spotter

A trained spotter reported a measured gust of 60 mph.

Tornado in HARRISON, INDIANA
From 19-APR-11 23:09:00 to 19-APR-11 23:10:00 (EST-5)
Location: CORYDON
Tornado F-scale: EF0
Reported by: NWS Storm Survey

An NWS storm survey confirmed an EF-0 tornado with wind speeds estimated at 65 mph.  The path length was approximately 0.3 miles with a width of 50 yards.  Numerous hardwood and softwood trees were either snapped or uprooted along the northern bank of Indian Creek.

Tornado in WASHINGTON, INDIANA
From 19-APR-11 23:14:00 to 19-APR-11 23:18:00 (EST-5)
Location: NEW PHILADELPHIA
Tornado F-scale: EF0
Reported by: NWS Storm Survey

An NWS storm survey confirmed an EF-0 tornado touched down in Washington county approximately 4 miles SSW of Little York.  The tornado continued for 13 miles into Scott county where it finally lifted 5 miles north northeast of Austin.  Maximum wind speeds were estimated to be 80 mph. Several trees were snapped or uprooted and a roof was damaged near North Rutherford Hollow Road. Mainly tree damage was observed along the rest of the path.

Thunderstorm Wind in ORANGE, INDIANA
From 19-APR-11 22:50:00 to 19-APR-11 22:50:00 (EST-5)
Location: ORLEANS ARPT
Magnitude: 55.00 MG
Reported by: Trained Spotter

A trained spotter reported a measured wind gust of 63 mph.

Thunderstorm Wind in CRAWFORD, INDIANA
From 19-APR-11 22:51:00 to 19-APR-11 22:51:00 (EST-5)
Location: ENGLISH
Magnitude: 56.00 MG
Reported by: Trained Spotter

A trained spotter reported a measured wind gust of 64 mph.

Tornado in SCOTT, INDIANA
From 19-APR-11 23:18:00 to 19-APR-11 23:27:00 (EST-5)
Location: LEOTA
Tornado F-scale: EF0
Reported by: NWS Storm Survey

An NWS storm survey confirmed an EF-0 tornado touched down in Washington county approximately 4 miles SSW of Little York. The tornado continued for 13 miles into Scott county where it finally lifted 5 miles north northeast of Austin. Maximum wind speeds were estimated to be 80 mph. Mainly tree damage was observed along the path in Scott county..

Thunderstorm Wind in CRAWFORD, INDIANA
From 19-APR-11 22:59:00 to 19-APR-11 22:59:00 (EST-5)
Location: LEAVENWORTH
Magnitude: 61.00 EG
Reported by: NWS Storm Survey

An NWS storm survey found sporadic straight line wind damage across southern Crawford and west central Harrison counties.  Numerous trees were damaged, the eaves on two houses as well as siding and shingles were blown off, and sheet metal was blown off a barn.  Winds were estimated to be up to 70 mph.

Tornado in WASHINGTON, INDIANA
From 19-APR-11 22:59:00 to 19-APR-11 23:01:00 (EST-5)
Location: LIVONIA
Tornado F-scale: EF1
Reported by: NWS Storm Survey

An NWS storm survey confirmed an EF-1 tornado with wind speeds up to 100 mph.  The tornado touched down at the intersection of West Batts Rd. and John Batt Road, where a grain bin was destroyed and several trees were blown over.  Just southwest of the Mount Tabor Road/West Washington Road intersection the twister destroyed two silos and a 20ft x 30ft outbuilding. A single story house also suffered severe damage at that location.  At the end of the damage path a house had its roof partially torn off and gravel from the driveway was lifted and pelted into the side of the house.

Thunderstorm Wind in PERRY, INDIANA
From 19-APR-11 23:02:00 to 19-APR-11 23:02:00 (EST-5)
Location: ROME
Magnitude: 55.00 MG
Reported by: Trained Spotter

A trained spotter reported a measured wind gust of 63 mph.

Tornado in WASHINGTON, INDIANA
From 19-APR-11 23:00:00 to 19-APR-11 23:01:00 (EST-5)
Location: LIVONIA
Tornado F-scale: EF0
Reported by: NWS Storm Survey

An NWS storm survey confirmed an EF-0 tornado with winds up to 75 mph.  This tornado traveled from the intersection of West Washington Road and Batt Road to just north of Mount Tabor Road.  Along its path a silo and two barns were damaged.  Several trees were knocked down or snapped.

Thunderstorm Wind in WASHINGTON, INDIANA
From 19-APR-11 23:15:00 to 19-APR-11 23:15:00 (EST-5)
Location: NEW PEKIN
Magnitude: 52.00 EG
Reported by: Trained Spotter

A trained spotter reported trees were blown down.

Thunderstorm Wind in FLOYD, INDIANA
From 19-APR-11 23:15:00 to 19-APR-11 23:15:00 (EST-5)
Location: NEW ALBANY
Magnitude: 56.00 EG
Reported by: Emergency Manager

A roof was blown off a house in eastern New Albany on Vincennes St.

Tornado in WASHINGTON, INDIANA
From 19-APR-11 23:07:00 to 19-APR-11 23:08:00 (EST-5)
Location: SALEM
Tornado F-scale: EF0
Reported by: NWS Storm Survey

An NWS storm survey confirmed an EF-0 tornado with wind speeds up to 80 mph.  This tornado touched down along Jim Day Road about a quarter mile south of Lewellen Road where a 30ft x 40ft outbuilding was destroyed and its roof thrown about 75 yards to the north and east.  The tornado ended just northeast of Lewellen Road where a house suffered roof damage, a 30ft x 50ft shed was destroyed, and a small grain bin was twisted and thrown 100 feet.

Thunderstorm Wind in ORANGE, INDIANA
From 19-APR-11 23:03:00 to 19-APR-11 23:03:00 (EST-5)
Location: VALEENE
Magnitude: 52.00 EG
Reported by: Trained Spotter

A trained spotter reported trees were blown down.

Thunderstorm Wind in HARRISON, INDIANA
From 19-APR-11 23:09:00 to 19-APR-11 23:09:00 (EST-5)
Location: CORYDON
Magnitude: 52.00 EG
Reported by: Trained Spotter

A trained spotter reported trees were blown down.

Thunderstorm Wind in HARRISON, INDIANA
From 19-APR-11 23:04:00 to 19-APR-11 23:09:00 (EST-5)
Location: WHITE CLOUD
Magnitude: 61.00 EG
Reported by: NWS Storm Survey

An NWS storm survey confirmed straight line wind damage with winds up to 70 mph across Crawford and Harrison counties.  Numerous trees were damaged and two houses lost siding, shingles, and eaves.  Sheet metal was blown off of a barn.  Most of the damage was found along Indiana 62.

Tornado in JEFFERSON, INDIANA
From 19-APR-11 23:40:00 to 19-APR-11 23:42:00 (EST-5)
Location: CHINA
Tornado F-scale: EF1
Reported by: NWS Storm Survey

The tornado touched down near the intersection of Indiana Highway 62 and E400N, severely damaging several outbuildings. A 2x4 from one of the outbuildings was driven through the exterior wall and into the kitchen of a home 1/10 mile away. The skipping storm then raced northeast across hilly rural terrain. Dozens of large hardwood trees were snapped or uprooted at a Girl Scout Campground on Geyman Hill Road. After exiting the campground, the tornado then destroyed a large barn and damaged the roofs of nearby homes and other outbuildings, as well as uprooting more trees. It lifted shortly after crossing China-Manville Road.

Tornado in SCOTT, INDIANA
From 19-APR-11 23:19:00 to 19-APR-11 23:25:00 (EST-5)
Location: SCOTTSBURG
Tornado F-scale: EF0
Reported by: NWS Storm Survey

An NWS storm survey confirmed an EF-0 tornado with wind speeds up to 80 mph touched down in Scottsburg, tearing off exterior wall panels of a 3-story Holiday Inn, as well as causing roof damage and snapping numerous large limbs in an adjacent residential area.  The tornado continued to the northeast into Jefferson county where it lifted approximately 2.5 miles east of Deputy.   Near Indiana 203 and North Bethlehem Road in Scott County several trees were down and agricultural buildings and residences experienced roof damage.

Thunderstorm Wind in CRAWFORD, INDIANA
From 19-APR-11 23:10:00 to 19-APR-11 23:10:00 (EST-5)
Location: LEAVENWORTH
Magnitude: 52.00 EG
Reported by: Trained Spotter

Trees and power lines were blown down.

Thunderstorm Wind in SCOTT, INDIANA
From 19-APR-11 23:17:00 to 19-APR-11 23:17:00 (EST-5)
Location: SCOTTSBURG
Magnitude: 52.00 EG
Reported by: County Official

A tree was blown down on to a garage on South Lake Rd.

Thunderstorm Wind in FLOYD, INDIANA
From 19-APR-11 23:20:00 to 19-APR-11 23:20:00 (EST-5)
Location: GALENA
Magnitude: 52.00 EG
Reported by: Trained Spotter

Trees were blown down.

Thunderstorm Wind in SCOTT, INDIANA
From 19-APR-11 23:20:00 to 19-APR-11 23:20:00 (EST-5)
Location: SCOTTSBURG
Magnitude: 52.00 EG
Reported by: County Official

A house on Sharon Dr. had a tree down.

Thunderstorm Wind in FLOYD, INDIANA
From 19-APR-11 23:23:00 to 19-APR-11 23:25:00 (EST-5)
Location: NEW ALBANY
Magnitude: 56.00 EG
Reported by: NWS Storm Survey

An NWS storm survey confirmed straight line wind damage with winds estimated to be 60-65 mph.  The most intense damage with this event was observed at a car wash at the junction of Vincennes Street and Elm Street where the top of the car wash was blown down.  Many large, old, shallow rooted trees were blown over in a west to east direction along Elm Street.  Sporadic straight line winds also damaged trees and a few chimneys along Oak Street and Culbertson Avenue as well.

Thunderstorm Wind in FLOYD, INDIANA
From 19-APR-11 23:26:00 to 19-APR-11 23:26:00 (EST-5)
Location: EDWARDSVILLE
Magnitude: 56.00 MG
Reported by: Trained Spotter

A trained spotter reported a measured wind gust of 64 mph.

Tornado in JEFFERSON, INDIANA
From 19-APR-11 23:25:00 to 19-APR-11 23:31:00 (EST-5)
Location: DEPUTY
Tornado F-scale: EF0
Reported by: NWS Storm Survey

An NWS storm survey confirmed an EF-0 tornado with wind speeds up to 80 mph moved into Jefferson County from Scott County.  The tornado, which touched down in Scottsburg, crossed the county line a half mile north of Highway 256 southwest of Deputy. it continued to the northeast over rural countryside, snapping and uprooting numerous trees and heavily damaging a hog barn and other outbuildings before lifting approximately 2.5 miles east of Deputy along Deputy Pike Road.

Thunderstorm Wind in HARRISON, INDIANA
From 19-APR-11 23:14:00 to 19-APR-11 23:14:00 (EST-5)
Location: CORYDON
Magnitude: 52.00 EG
Reported by: Trained Spotter

Trees and power lines were blown down.

Tornado in CLARK, INDIANA
From 19-APR-11 23:28:00 to 19-APR-11 23:29:00 (EST-5)
Location: JEFFERSONVILLE ARPT
Tornado F-scale: EF1
Reported by: NWS Storm Survey

An NWS storm survey confirmed an EF-1 tornado with wind speeds up to 90 mph.  The tornado started in Sunset Trailer Park where about two dozen trailers were damaged.  Several trailers were moved off of their foundations and had roof damage.  One trailer's roof was thrown 65 yards.  Trees and power lines were damaged as well.  The tornado then weakened slightly to 80 mph as it moved northeast into a subdivision damaging several small trees, sheds, and roofs.  A trampoline was thrown and wrapped around a shed and a tree.  More tornado damage was then found at the end of a subdivision right behind a church off of Holmans Lane.  The south side of the church was completely blown out.  Sheds were destroyed and trees uprooted.  Insulation was thrown from north to southeast.  Across Holmans Lane tree and shingle damage was found.  The path ended near Indiana 62.

Tornado in JEFFERSON, INDIANA
From 19-APR-11 23:41:00 to 19-APR-11 23:44:00 (EST-5)
Location: BRYANTSBURG
Tornado F-scale: EF0
Reported by: NWS Storm Survey

An NWS storm survey confirmed an EF-1 tornado with winds up to 100 mph. This fast-moving tornado began along U.S. 421 one half mile south of the Jefferson-Ripley County line, then raced eastward, doing minor damage to a home, sucking the door out of a large garage and taking off much of the roof of a large tobacco barn. The most extensive damage was done near the end of the tornado's path where it destroyed a mobile home, took the roof off a cinder block outbuilding, and did extensive damage to the roofs of several large barns.

Thunderstorm Wind in JEFFERSON, INDIANA
From 19-APR-11 23:28:00 to 19-APR-11 23:28:00 (EST-5)
Location: DEPUTY
Magnitude: 56.00 EG
Reported by: Law Enforcement

Damage to a barn and garage near state road 3 in Deputy was reported.  Trees and power lines were also downed county-wide in Jefferson county.

Thunderstorm Wind in SCOTT, INDIANA
From 19-APR-11 23:29:00 to 19-APR-11 23:29:00 (EST-5)
Location: AUSTIN
Magnitude: 54.00 MG
Reported by: Trained Spotter

A trained spotter reported a measured gust of 62 mph.

Tornado in CLARK, INDIANA
From 19-APR-11 23:28:00 to 19-APR-11 23:29:00 (EST-5)
Location: JEFFERSONVILLE ARPT
Tornado F-scale: EF0
Reported by: NWS Storm Survey

An NWS storm survey confirmed an EF-0 tornado with wind speeds up to 75 mph.  The tornado snapped trees and damaged a shed and shingles.  The tornado began on the east side of the Sunset Trailer Park and ended at Charlestown Pike.

Thunderstorm Wind in SCOTT, INDIANA
From 19-APR-11 23:29:00 to 19-APR-11 23:29:00 (EST-5)
Location: SCOTTSBURG
Magnitude: 56.00 EG
Reported by: Broadcast Media

Trees were blown down county-wide.  Some were blocking roads.

Thunderstorm Wind in JEFFERSON, INDIANA
From 19-APR-11 23:36:00 to 19-APR-11 23:36:00 (EST-5)
Location: LANCASTER
Magnitude: 56.00 EG
Reported by: Storm Chaser

Trees were blown down between Deputy and Lancaster.

Tornado in DUBOIS, INDIANA
From 19-APR-11 22:22:00 to 19-APR-11 22:23:00 (EST-5)
Location: HUNTINGBURG
Tornado F-scale: EF0
Reported by: NWS Storm Survey

An NWS storm survey confirmed an EF-0 tornado with wind speeds of 80 mph north of Huntingburg. A large swath of hardwood trees was snapped and uprooted.  In addition to tornado damage, straight-line winds up to hurricane force were found in the area.