EF4 Cullman–Arab tornado, Alabama, April 27, 2011

1. EF065 to 85 mph

   Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.

2. EF186 to 110 mph

   Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.

3. EF2111 to 135 mph

   Considerable damage. Roofs torn off well-built houses, frame homes shifted on their foundations, mobile homes destroyed, large trees snapped or uprooted, cars lifted off the ground.

4. EF3136 to 165 mph

   Severe damage. Whole stories of well-built houses destroyed, large buildings badly damaged, trains overturned, trees debarked, heavy cars lifted and thrown.

5. EF4166 to 200 mphthis tornado

   Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.

6. EF5over 200 mph

   Incredible damage. Strong frame houses swept off their foundations, car-sized missiles thrown more than 100 meters, steel-reinforced concrete badly damaged, high-rise buildings deformed.

7. Unrated

   The survey recorded a tornado but could not put a number on it, most often because it crossed open country and damaged nothing a rating can be read from.

Rating

EF4

Date

April 27, 2011

Touchdown

2:40 PM CDT (19:40 UTC)

Lifted

3:38 PM CDT (20:38 UTC)

On the ground

58 minutes

Path length

46.9 miles (75.4 km)

Path width

880 yards (805 m)

Deaths

6

Injuries

48

Counties

Cullman, Morgan and Marshall counties

Touchdown point

34.076, -87.010

Lift-off point

34.493, -86.363

Record number

1104271340-01

42 damage points were recorded along this path by NWS BMX and NWS HUN, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF4. The highest wind the damage implies is 175 mph.

• .Area of trees snapped on hillside. Estimated point.
• .Many trees uprroted, those snapped were branches. Home damaged by fallen trees here.
• .Hardwoods snapped and uprooted in this area.
• .Snapped trees at top of hill

Survey points are preliminary and are the raw material the published rating was built from. Source: NWS Damage Assessment Toolkit.

A powerful storm system roared across the Southeast United States on Wednesday, April 27, 2011. In the wake of this system, hundreds of people were left injured and/or homeless, along with approximately 100 people who lost their lives in the northern Alabama area alone. Some of the devastation was literally unimaginable with countless homes, neighborhoods and even portions of cities or towns either partially or completely destroyed. This storm system would be responsible for one of the largest and deadliest tornado outbreaks to ever impact much of the southeastern region.| |The powerful storm system that affected the National Weather Service, Huntsville service area would actually occur in three separate waves of severe weather that day. The first occurred during the early morning hours of April 27, 2011 roughly between the hours of 2 AM and 8 AM CDT, while the second occurred during the late-morning to early afternoon period. The third and most devastating wave occurred during the afternoon hours on Wednesday, with some of the most violent and destructive tornadoes to affect the central Tennessee Valley area in recent decades.| |The worst areas impacted by these storms included the towns of Phil Campbell and Oak Grove in eastern Franklin County Alabama, Mt. Hope in western Lawrence County and the Tanner Community in eastern Limestone County. Along a line connecting these areas tracked an EF5 tornado with peak winds around 210 mph, the strongest and most violent on the Enhanced Fujita Scale. ||Other areas impacted by the storms include the city of Cullman, where extensive damage occurred to buildings in the downtown area, and to the town of Fairview, both of which are located in Cullman County. Downstream, further significant damage occurred to the Ruth and Oak Grove communities in Marshall County. In addition, the communities of Rainsville and Sylvania along with the towns of Henagar and Ider in DeKalb County were severely impacted. Fatalities in DeKalb County alone numbered at least 33 people. Furthermore, the towns of Flat Rock, Higdon and Pisgah in Jackson County sustained incredible damage. The tornadoes that affected these areas were rated as an EF4 with maximum winds near 190 mph.||In most of these areas alone, numerous people lost their lives. These represent just several of the communities and towns impacted by the events of April 27, 2011. While the majority of the analysis and survey work conducted by the National Weather Service, Huntsville and its partners have been completed, there will undoubtedly be countless research studies conducted by both academia and operational personnel in order to further evaluate and understand the complex processes associated with this near unprecedented severe weather outbreak.

A violent long track tornado developed on the north side of Lewis Smith Lake along County Road 310 where some light damage was found. The tornado tracked northeast snapping numerous large trees and causing significant structural damage to residences along County Roads 222 and 436 near Grandview. The tornado tracked northeast into the city of Cullman. Some of the worst damage occurred just northeast of U.S. Highways 31 and 278. Several small retail buildings were completely destroyed. along with the near total destruction of a large church. The tornado tracked across State Highway 157, then caused additional damage north of State Highway 69 between Simcoe and Pleasant View. Just north of Fairview along County Roads 1559 and 1564, 2 homes were destroyed with significant portions of the homes not found. Further northeast along County Road 1589, the tornado caused major structural damage to several old (early 1900s) homes. Numerous hardwood trees were debarked. A 1/4 to 1/2 mile wide corridor of significant damage persisted between Fairview and the Morgan County line.

A violent tornado tracked from Cullman County into extreme southeast Morgan County near the town of Hulaco. Peak wind speeds of up to 175 mph caused significant damage between Hyatt Bottom Road and Blocker Road, just east of State Highway 67. Several cinder block and old construction homes were destroyed, and numerous trees were snapped and sheared toward the base.

A violent tornado with peak wind speeds of 190 mph crossed into northwest Marshall County (from Morgan County). The most severe damage occurred on either side of U.S. Highway 231 north of Arab -- particularly in the Ruth community and along Hog Jaw Road -- about 3 miles north of Arab. Along Hog Jaw Road, a large storage shed with farm equipment was destroyed with some of the large machinery tossed 10 to 20 yards around the shed. In the Ruth community, Mount Oak and Frontier Roads were hardest hit where a cinder block/cement home was nearly wiped clean. Debris from a home on Frontier Road was thrown 50 to 100 yards away. A family of 9 was in this house and 5 were killed. A trailer was missing and a metal-bolted garage was wiped clean of its foundation. Along Frontier Road, a large brick home was nearly wiped clean off its foundation with several large trees ripped out of the ground and missing. Further northeast along the path, along Walnut Ridge, a one-story home was severely damaged with the roof missing and a trailer that was tossed into a tree. Several concrete power poles were bent over as the tornado crossed U.S. Highway 231, some bent at the base. One the east side of Highway 231, a gas station building was completely demolished and two gas pumps were ripped from the ground and missing. The canopy over the pumps remained mostly intact.||The tornado continued toward Union Grove. The degree of damage weakened somewhat but several homes had significant damage where the top stories and roofs were destroyed and the external walls had collapsed. Along County Road 240, a double-wide manufactured home was destroyed and a large garage collapsed but the well-built roof remained intact.||The tornado significantly weakened as it crossed the Tennessee River. On the other side of the river, the tornado snapped and uprooted numerous trees as it crossed Walker Road and just across U.S. Highway 431 before lifting just northeast of Highway 431.

The deaths

6 direct deaths are recorded for this tornado, each with what Storm Data knows of it.

From NOAA NCEI's Storm Events Database, the narrative the local forecast office wrote for Storm Data.

16 minutes of warning. NWS HUN issued a tornado warning for this county at 19:24 UTC, 16 minutes before the tornado touched down, in force until 20:00 UTC.

The county was under a tornado watch, issued at 18:45 UTC and running to 01:45 UTC.

Every warning and watch covering the touchdown point that day, from the Iowa Environmental Mesonet's archive of National Weather Service products. Lead time is measured from the issue of the warning in force to the touchdown time in the database, both of which were recorded to the minute by different people.

The Storm Prediction Center had this point in a High Risk, with a 0.45 chance of a tornado within 25 miles, in the hatched area where significant tornadoes were expected. The outlook in force was issued at 16:29 UTC.

SPC's Day 1 convective outlook as it stood when the tornado began, read at the touchdown point. The same archive is on the radar archive.

The radiosonde launches on either side of the tornado, from the nearest station that was launching then, drawn and analyzed the way Storm Lab does: the same diagram, the same parcel and shear definitions SPC's mesoanalysis uses.

The Northeast Alabama radar (KHTX), 91 km away, was scanning. The volume nearest the touchdown began at 19:42 UTC.

Open the radar archive at this moment, over the track

Reflectivity and velocity, decoded from the Level II archive in the browser. Volumes take a few seconds to open the first time.

Local storm reports within 60 km of the path, in the three hours either side.

From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.

The live radar over the trackEvery 2011 tornado in AlabamaEvery tornado in Alabama since 1950Warnings in force in Alabama nowThe forecast where you are

209 more were confirmed in the United States that day.

All 210 of them

Ratings are the survey's, read off the damage rather than measured; the rating scale is above. Tornado counts rise through the record as reporting improved, so a year in the 1950s is not comparable with one today except for the strongest tornadoes, which were always noticed.

NOAA Storm Prediction Center tornado database, 1950-2025, the official record kept by NOAA's Storm Prediction Center.