EF1 tornado, Alcorn to Gordon, Mississippi, May 3, 2009

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

May 3, 2009

Touchdown

9:55 AM CDT (14:55 UTC)

Lifted

10:02 AM CDT (15:02 UTC)

On the ground

7 minutes

Path length

4.6 miles (7.4 km)

Path width

50 yards (46 m)

Deaths

0

Injuries

0

Property damage

$15,000

County

Claiborne County

Touchdown point

31.890, -91.060

Lift-off point

31.924, -90.992

Record number

0905030855-01

Early on the 3rd, clusters of severe storms evolved into a line which produced scattered wind damage as it pushed east along and just north of I-20. An outflow boundary pushed out of this line and provided the focus for the second powerful and significant severe event.||Between 8 am and 1 pm, a Derecho evolved and raced east across the southern half of the forecast area at 60 to 70 mph. A Derecho is defined as a long lived windstorm, usually a large bow echo, which has a width of 40 to 250 miles and covers a long distance, typically one to three states. This large bowing squall line brought intense straight line winds and widespread damage across its swath. Some of the wind speeds within this Derecho ranged between 80 and 95 mph. There were numerous reports of trees down as well as downed power lines, which caused widespread power outages in many locations. Many structures were damaged by either fallen trees or just the wind itself. Scattered reports of hail and a few tornadoes also occurred. One fatality occurred in Jones County as a tree fell through a woman���s mobile home.||During the early predawn hours of May 4th. Isolated severe storms affected northern Forest county with some flash flooding.

The tornado started along Russum Westside road, snapping and downing a number of trees and large limbs along the road. The tornado then crossed Old Colony Road, downing several trees and large limbs across the road. The weakening tornado then crossed the Natchez Trace Parkway and US Highway 61, downing a few trees and large limbs, before dissipating. Maximum winds were around 90 mph.

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

36 minutes of warning. NWS JAN issued a tornado warning for this county at 14:19 UTC, 36 minutes before the tornado touched down, in force until 15:15 UTC.

The county was under a severe thunderstorm watch, issued at 12:50 UTC and running to 16:15 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 Moderate Risk, with a 0.05 chance of a tornado within 25 miles. The outlook in force was issued at 12:30 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), 107 km away, was scanning. The volume nearest the touchdown began at 14:54 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 2009 tornado in MississippiEvery tornado in Mississippi since 1950Warnings in force in Mississippi nowThe forecast where you are

21 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.