EF0 tornado, Grove Oak to Ten Broeck, Alabama, April 3, 2015

1. EF065 to 85 mphthis tornado

   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 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

EF0

Date

April 3, 2015

Touchdown

8:15 PM CDT (01:15 UTC)

Lifted

8:16 PM CDT (01:16 UTC)

On the ground

1 minutes

Path length

0.9 miles (1.5 km)

Path width

30 yards (27 m)

Deaths

0

Injuries

0

County

DeKalb County

Touchdown point

34.461, -86.016

Lift-off point

34.461, -86.000

Record number

1504031915-01

7 damage points were recorded along this path by NWS HUN, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF0. The highest wind the damage implies is 85 mph.

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

A cold front intersecting a warm and unstable environment led to a broken band of thunderstorms during the late afternoon and evening hours, some of which were supercellular in nature. These storms moved east-southeast at 35-45 mph and exited northern Alabama between 930 and 10 pm CDT. One tornado was confirmed in DeKalb County with a few narrow swaths of wind damage reported in other portions of north Alabama.

A storm survey determined that a weak tornado touched down in the Fyffe, Alabama, community just east of the intersection of County road 545 and County Road 50. A few softwood trees were uprooted on the north side of the road. The tornado then moved east, crossing County Road 50 briefly, and uprooting some trees along County Road 536. The tornado then nearly paralleled County Road 50, destroying a large hay barn just east of County Road 528. The winds within the tornado along County Road 528 were estimated at around 85 mph with a narrow path of 30 yards. The tornado finally lifted west of County Road 539 after downing a few more trees.

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

No tornado warning for this county appears in the archive as in force at the moment the tornado touched down. One was issued for the county at another hour that day.

The county was under a severe thunderstorm watch, issued at 23:50 UTC and running to 03:00 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 Slight Risk, with a 0.05 chance of a tornado within 25 miles. The outlook in force was issued at 00:38 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), 53 km away, was scanning. The volume nearest the touchdown began at 01:16 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 2015 tornado in AlabamaEvery tornado in Alabama since 1950Warnings in force in Alabama nowThe forecast where you are

4 more were confirmed in the United States that day.

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.