EF1 tornado, Carlisle to Roundtop, Georgia, December 22, 2011

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

December 22, 2011

Touchdown

5:32 PM EST (22:32 UTC)

Lifted

5:34 PM EST (22:34 UTC)

On the ground

2 minutes

Path length

1.5 miles (2.4 km)

Path width

300 yards (274 m)

Deaths

0

Injuries

0

Property damage

$75,000

County

Gilmer County

Touchdown point

34.575, -84.647

Lift-off point

34.585, -84.623

Record number

1112221632-01

5 damage points were recorded along this path by NWS FFC, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF3. The highest wind the damage implies is 150 mph.

• House destroyed at 2073 Boone Ford Rd with debris thrown at least 300 yards.
• A total of 100 trees were downed or snapped with around 6 power poles also downed. Shady Grove church received minor damage.

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

A deep trough, quite characteristic of the early winter season of 2011-2012, was anchored across the southwest U.S. with broad southwest flow aloft evident from the southwest U.S. toward the mid-Atlantic. A summer-like Bermuda high pressure area was anchored off the southeast U.S. coast. A stationary front extended across the lower Mississippi valley toward the mid-Atlantic with a cold front approaching from the west of this region from Texas toward the Great lakes. The air mass across the region in advance of the stationary front was extremely moist, warm, and unstable for mid-December. As an embedded strong short wave traversed the region in the southwest flow aloft, a period of strong shear and marginal instability translated across the region during the late afternoon and early evening. These synoptic features supported a strong to severe quasi-linear convective system, or squall line, which moved across the state from west to east during the late afternoon and evening. The line of thunderstorms spawned a half-a-dozen tornadoes causing extensive damage across several counties from west central into northwest and north central Georgia. As the line moved east past Atlanta, it weakened considerably and no further severe weather was observed across east Georgia. The six tornadoes occurring on this date tied the record for the most tornadoes ever occurring during December within the Peachtree City, Georgia county warning area in December, namely six in 2005.

The Gilmer County Emergency Management Director reported and the Cherokee County Emergency Management Director discovered an area of damage in southwest Gilmer county. The Cherokee County Emergency Management Director determined that the damage was the result of an EF1 tornado. The tornado touched down approximately four miles southeast of Carters (in Murray county) in far southwest Gilmer county near Georgia Highway 136. The tornado tracked on the ground, paralleling Georgia Highway 136, in an east-northeastward direction for only 1.5 miles before lifting near the intersection of Camp Branch Road and Georgia Highway 136. The damage path was determined to be 300 yards wide with maximum winds estimated to be 90 mph. The most significant damage resulting from the tornado was to the Shady Grove Church, which sustained minor damage from falling trees. No other structures were damaged. However, a total of at least 100 trees and six power poles were snapped or downed by the tornado.||[12/22/11: Tornado #3, County #1-1, EF1, Gilmer, 2011:029].

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 tornado watch, issued at 20:25 UTC and running to 23:29 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 19:51 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 Atlanta radar (KFFC), 135 km away, was scanning. The volume nearest the touchdown began at 22:30 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 GeorgiaEvery tornado in Georgia since 1950Warnings in force in Georgia nowThe forecast where you are

12 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.