EF0 tornado, Ogden to Dubberly, Louisiana, November 8, 2011

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

November 8, 2011

Touchdown

6:20 PM CST (00:20 UTC)

Lifted

6:31 PM CST (00:31 UTC)

On the ground

11 minutes

Path length

5.6 miles (8.9 km)

Path width

75 yards (69 m)

Deaths

0

Injuries

0

County

Webster Parish

Touchdown point

32.462, -93.290

Lift-off point

32.503, -93.208

Record number

1111081820-01

1 damage points were recorded along this path by NWS SHV, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF0.

• tree down. shed destroyed behind the house

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

A potent upper level storm system moved out of the Texas Hill County and into the Southern Plains during the afternoon of November 11th. Deep layer shear and low level shear was significant enough for supercells and mesocyclones during the afternoon and evening hours across the region given the instability in place. Discrete storms developed ahead of a strong cold front and some of these storms produced damaging wind gusts, large hail and tornadoes.

This tornado was part of the same supercell thunderstorm which spawned the tornadoes near Logansport and Elm Grove Louisiana. It was also one of two tornadoes in close proximity. The tornado first touched down along Hwy. 7 about 1.5 miles northwest of Heflin, Louisiana. The tornado then tracked northeast crossing Mason Fells Road and Hwy. 531 with several trees snapped and uprooted along the path before ending on Coussons Road, about 3 miles southeast of Dubberly, Louisiana. Winds were estimated at 75-80 mph.

This tornado was part of the same supercell thunderstorm which spawned the tornadoes near Logansport and Elm Grove, Louisiana. It was also one of two tornadoes in close proximity. This tornado first touched just west of the intersections of Coussons Road and Hwy. 531 and moved northeast snapping and uprooting several trees. The tornado crossed Magnolia Road and eventually lifted along Harvey���s Barber Shop Road where several large tree limbs were broken. Winds were estimated at 65-70 mph.

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

20 minutes of warning. NWS SHV issued a tornado warning for this county at 00:00 UTC, 20 minutes before the tornado touched down, in force until 00:45 UTC.

The county was under a tornado watch, issued at 23:33 UTC and running to 02:45 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 Slight Risk, with a 0.05 chance of a tornado within 25 miles. The outlook in force was issued at 19:56 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 Shreveport radar (KSHV), 56 km away, was scanning. The volume nearest the touchdown began at 00:20 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 LouisianaEvery tornado in Louisiana since 1950Warnings in force in Louisiana nowThe forecast where you are

10 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.