EF1 tornado, Mc Ville to Whitesboro, Alabama, March 18, 2013

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

March 18, 2013

Touchdown

3:41 PM CDT (20:41 UTC)

Lifted

3:48 PM CDT (20:48 UTC)

On the ground

7 minutes

Path length

8.0 miles (12.8 km)

Path width

300 yards (274 m)

Deaths

0

Injuries

3

Counties

Etowah and Marshall counties

Touchdown point

34.205, -86.153

Lift-off point

34.191, -86.014

Record number

1303181441-01

119 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 EF2. The highest wind the damage implies is 125 mph.

• new power poles already up.
• tin/debris from shed thrown across road.
• debris field extending from EF-1 damage to barn
• picture taken from road, looking south. Damage about 150 yards away.

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

An active severe weather episode was produced by two quasi-linear convective systems. The first developed during the midday hours across middle Tennessee into northwest Alabama, while another which originated as a small convective cluster in central Arkansas rapidly intensified and raced eastward through northern Mississippi into north Alabama during the afternoon hours. Numerous reports of wind damage, large hail and four tornadoes. Two of the tornadoes injured ten people and produced significant damage to mobile homes, trees, and power poles.

An upper trough became negatively tilted as it moved into the Mississippi River Valley. A strong cold front trailed southward from the trough and swept through the state. Ahead of this cold front, an intense derecho moved through central Alabama during the afternoon and evening hours of Monday, March 18th. The morning started out cloudy across Alabama, but as dry air aloft filtered into the state from the southwest, the clouds thinned, allowing surface based instability to increase into the 1250-1750 J/kg range ahead of the developing line of thunderstorms. As the line entered the state from Mississippi, it brought with it damaging straight line winds of widespread reports of 60 to 80 mph, including a measured report of 88 mph. These winds resulted in trees and power lines down across the northern two-thirds of central Alabama. Along with the wind from the derecho, up to two inch hail was reported and eventually a tornado spun up in northern Etowah County. Ahead of the derecho, discrete thunderstorms developed as well. It was within these individual storms where some of the largest hail was reported, including baseball sized hail in Chilton County.

A tornado produced EF0 to EF1 damage, with wind speeds up to 100 mph along a path beginning along Hambey Road just east of McVille Road. Several softwood and hardwood trees were either uprooted or snapped along Hambey Road. As the tornado moved east, several wooden power poles were snapped. Several farm buildings were destroyed with debris strewn over 100 yards. Additional tree damage was noted along County Roads 381 and 82. The tornado crossed into DeKalb County east of Gaines Road.

A tornado touched down just east of U.S. Highway 431 in Boaz just south of Bruce Road producing minor structural damage to businesses along Highway 431. The tornado tracked east-southeast crossing McVille Road and Alabama Highway 168 causing minor tree damage. The tornado intensified and widened to 300 yards as it crossed Bethsaida Road, when it uprooted and snapped numerous trees as it approached Alewine Road, just north of Ellis Road. The tornado then crossed into Etowah County about a half of a mile west of Oak Drive.

The tornado initially touched down in Marshall County in Boaz and moved eastward into Etowah County about a half of a mile west of Oak Drive where it snapped and uprooted several pine trees. From there it moved to the east and crossed Broadwell Road and overturned a tractor trailer and a camper. The tornado continued eastward, snapping and uprooting trees along the path. Several barns and small outbuildings sustained roof damage. As the tornado crossed Chumley Road, two mobile homes were overturned while more trees were uprooted. The most extensive damage occurred as the tornado approached Rowen Road. A mobile home was lifted and overturned leaving one person seriously injured and two others with minor injuries. In this same area, two additional mobile homes were destroyed. As the tornado crossed Brow Road, a one story brick home had one third of its roof removed and wind-blown debris was observed on all four sides of the home. The tornado continued further east for approximately 300 yards before dissipating as it approched Sand Valley Road.

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.

The county was under a severe thunderstorm watch, issued at 18:32 UTC and running to 21:43 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 19:31 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), 81 km away, was scanning. The volume nearest the touchdown began at 20:42 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 2013 tornado in AlabamaEvery tornado in Alabama since 1950Warnings in force in Alabama nowThe forecast where you are

9 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.