EF0 tornado, Martinville, Mississippi, September 20, 2013

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

September 20, 2013

Touchdown

9:57 PM CDT (02:57 UTC)

Lifted

10:05 PM CDT (03:05 UTC)

On the ground

8 minutes

Path length

3.2 miles (5.2 km)

Path width

50 yards (46 m)

Deaths

0

Injuries

0

County

Simpson County

Touchdown point

32.005, -89.698

Lift-off point

32.045, -89.669

Record number

1309202057-01

18 damage points were recorded along this path by NWS JAN, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF1. The highest wind the damage implies is 100 mph.

• Large chicken house destroyed
• Debris scattered across field
• Beginning of tornado track
• Small trees snapped and large branches downed along Sixteen Section Rd

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

Much needed heavy rain fell across the ArkLaMiss beginning on the 20th and continuing into the 21st ahead of an approaching cold front. High moisture content was present ahead of this front as atmospheric profiles showed moisture content nearing two standard deviations above normal for late September. This set the stage for several inches of rain to fall over a region that was seeing below normal monthly rainfall, burn bans and high fire danger. A steady rain fell during the overnight hours of the 20th into the 21st, bringing a widespread one to three inches of rain to the ArkLaMiss. The heaviest rain fell along the Natchez Trace Parkway corridor, where three to five inches of rain fell. ||In addition to the rains, five tornadoes occurred during the evening and overnight hours. These tornadoes were small and brief, and were embedded in the rain shield as it sweeped across the region. The first three tornadoes that occurred were in smaller discrete cells, while the last two occurred in a strong rain band. Much of the damage was minor, and no fatalities or injuries occurred.

The tornado tracked across a rural wooded area and snapped several large trees. Maximum sustained winds were 75 mph.

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.

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 General Thunderstorms Risk. The outlook in force was issued at 00:30 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 Jackson/Brandon,MS radar (KDGX), 40 km away, was scanning. The volume nearest the touchdown began at 02:56 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 MississippiEvery tornado in Mississippi since 1950Warnings in force in Mississippi nowThe forecast where you are

3 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.