EF1 tornado, Cluttsville to Monrovia, 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 mphthis tornado

   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 mph

   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

EF1

Date

April 27, 2011

Touchdown

4:53 PM CDT (21:53 UTC)

Lifted

5:07 PM CDT (22:07 UTC)

On the ground

14 minutes

Path length

14.6 miles (23.5 km)

Path width

75 yards (69 m)

Deaths

0

Injuries

0

Counties

Limestone and Madison counties

Touchdown point

34.666, -86.917

Lift-off point

34.780, -86.701

Record number

1104271553-01

43 damage points were recorded along this path by NWS HUN, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF4. The highest wind the damage implies is 198 mph.

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.

An EF-1 tornado reaching peak wind speed of 105 mph began near Smith Road. Several houses sustained a significant amount of shingle damage. Numerous large trees were uprooted, snapped off, and an RV trailer was overturned along this road. Some of these trees were snapped off near their base. Also, the edifice of a brick home was damaged. At this point, the width of the tornado was at it's widest point (approximately 100 yards). As this tornado moved east northeast across Iron Horse Trail Road and across Orvil Smith Road, several areas of large trees (some snapped) were observed. This tornado continued east northeast, weakening slightly, but still uprooted large trees and produced minor roof damage. Portions of Shortleaf Road and Poplar Green Road were affected next by similar damage. Some fences were blown down in this area. The tornado lifted shortly before reaching Wall Triana Highway.

The tornado began near mile markers 342 and 343, producing EF-0 intensity winds of up to 70 mph and snapping trees. The tornado then continued moving northeast producing generally minor and sporadic tree damage in rural areas of Limestone county along Brownsferry Road. It then continued its path northeast into Madison county.

The tornado continued its path from Limestone into Madison county producing minor and sporadic damage. As it moved into Madison county the tornado intensified. It began uprooting large trees and producing some minor damage to homes in several locations. The most notable damage occurred in Madison along Balch Road near Kentucky Drive, Wall Triana at Gooch Lane, along McCrary Road, and further northeast along Capshaw Road between Nance Road and Jeff Road. From McCrary Road to Jeff Road, the width of tornado damage increased to approximately 75 yards. The tornado then continued moving northeast across Bishop Creek Road to Holbrook Drive. Damage along this portion of the track included uprooted large trees, some snapped-off tree tops, and minor roof damage. The tornado finally lifted further northeast on Holbrook Drive.

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

14 minutes of warning. NWS HUN issued a tornado warning for this county at 21:39 UTC, 14 minutes before the tornado touched down, in force until 22:15 UTC.

The county was under a tornado watch, issued at 18:45 UTC and running to 01:04 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 0.30 chance of a tornado within 25 miles, in the hatched area where significant tornadoes were expected. The outlook in force was issued at 19:12 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), 70 km away, was scanning. The volume nearest the touchdown began at 21:53 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.