Tornadoes · United States · Georgia · 2020

EF0 tornado, Grooverville to Pidcock, Georgia, September 16, 2020

From Grooverville to Pidcock, this EF0 tornado ran 3.0 miles across Brooks County on September 16, 2020, touching down at 4:40 PM EDT and reaching 50 yards wide. It killed nobody.

The rating scale

Tracks are drawn in the color of the rating. The Enhanced Fujita scale rates the damage rather than measuring the wind: the speeds are what that damage is taken to imply.

  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.

The record

Rating
EF0
Date
September 16, 2020
Touchdown
4:40 PM EDT (20:40 UTC)
Lifted
4:45 PM EDT (20:45 UTC)
On the ground
5 minutes
Path length
3.0 miles (4.8 km)
Path width
50 yards (46 m)
Deaths
0
Injuries
0
County
Brooks County
Touchdown point
30.745, -83.729
Lift-off point
30.788, -83.733
Record number
2009161440-01

What the Weather Service recorded

Hurricane Sally made landfall early on the morning of September 16 across Gulf Shores Alabama. The greatest impacts to the tri-state area came in the form of very heavy rain and significant flooding on and away from area rivers. Record river flooding occurred on the Shoal River at Mossy Head as well as Holmes Creek at Vernon.

A tornado tracked along the Brooks/Thomas county line with damage to trees. A dual-pol tornadic debris signature was observed on radar. No structural damage was reported, and this tornado was rated EF0.

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

The warnings

25 minutes of warning. NWS TAE issued a tornado warning for this county at 20:15 UTC, 25 minutes before the tornado touched down, in force until 20:45 UTC.

The county was under a tornado watch, issued at 17:22 UTC and running to 01:00 UTC.

Issued (UTC)ExpiredProductOffice
17:22 UTC01:00 UTCTornado WatchTAE
19:05 UTC07:00 UTCFlash Flood WatchTAE
20:15 UTC20:45 UTCTornado WarningTAE
20:47 UTC21:15 UTCTornado WarningTAE
21:04 UTC21:45 UTCTornado WarningTAE

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 forecast that day

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 19:44 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 air that afternoon

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.

Tallahassee Rgnl, FL (KTLH), 12:00Z

8.7 hours before the tornado, 68 km from the path. September 16, 2020.

Skew-T log-pSkew-T log-p diagram, Tallahassee Rgnl, FL at 12:00Z on 2020-09-16Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 181 joules per kilogram, CIN -39, lifted condensation level 788 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed. The warm shading is its CAPE, the cool shading the inhibition it has to break through.
HodographHodograph, Tallahassee Rgnl, FL at 12:00Z on 2020-09-16The wind through the lowest 10 kilometers as a curve, rings every 10 meters per second labeled in knots. Zero to 1 km storm-relative helicity 286 square meters per square second, 0 to 6 km bulk shear 33 knots.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km. RM and LM are the right and left moving storms Bunkers' method gives; the shaded area is the 0 to 1 km storm-relative helicity.
Mixed-layer CAPE
181 J/kg
Mixed-layer CIN
-39 J/kg
Surface CAPE
599 J/kg
Mixed-layer LCL
788 m above ground
0-6 km bulk shear
33 kt
0-1 km bulk shear
35 kt
0-1 km storm-relative helicity
286 m²/s²
0-3 km storm-relative helicity
397 m²/s²
Significant tornado parameter
0.2
Supercell composite
2.4
0-3 km lapse rate
4.8 K/km

Open this sounding in Storm Lab

Tallahassee Rgnl, FL (KTLH), 00:00Z

3.3 hours after it, 68 km from the path. September 17, 2020.

Skew-T log-pSkew-T log-p diagram, Tallahassee Rgnl, FL at 00:00Z on 2020-09-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 852 joules per kilogram, CIN -1, lifted condensation level 535 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed. The warm shading is its CAPE, the cool shading the inhibition it has to break through.
HodographHodograph, Tallahassee Rgnl, FL at 00:00Z on 2020-09-17The wind through the lowest 10 kilometers as a curve, rings every 10 meters per second labeled in knots. Zero to 1 km storm-relative helicity 302 square meters per square second, 0 to 6 km bulk shear 44 knots.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km. RM and LM are the right and left moving storms Bunkers' method gives; the shaded area is the 0 to 1 km storm-relative helicity.
Mixed-layer CAPE
852 J/kg
Mixed-layer CIN
-1 J/kg
Surface CAPE
1784 J/kg
Mixed-layer LCL
535 m above ground
0-6 km bulk shear
44 kt
0-1 km bulk shear
38 kt
0-1 km storm-relative helicity
302 m²/s²
0-3 km storm-relative helicity
344 m²/s²
Significant tornado parameter
1.4
Supercell composite
12.2
0-3 km lapse rate
5.4 K/km

Open this sounding in Storm Lab

The radar

The Tallahassee radar (KTLH), 70 km away, was scanning. The volume nearest the touchdown began at 20:41 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.

What was reported nearby

Local storm reports within 60 km of the path, in the three hours either side.

Time (UTC)ReportWhereCountyRemark
18:12 UTCTSTM WND DMG3 Wsw Pine ParkGrady, GATSTM WIND CAUSING SCATTERED POWER OUTAGES IN GRADY COUNTY.
19:31 UTCFLASH FLOOD2 Nnw LaneyMitchell, GAWATER OVER GA SR 37 NEAR DOZIER NORMAN RD AND MITCHELL COUNTY RD.
20:50 UTCTORNADO3 Ne MorvenBrooks, GA
21:00 UTCTSTM WND DMG4 Nne ValdostaLowndes, GAREPORT OF A TREE DOWN NEAR MORGAN RD.

From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.

This ground now

The live radar over the trackEvery 2020 tornado in GeorgiaEvery tornado in Georgia since 1950Warnings in force in Georgia nowThe forecast where you are

The other tornadoes of September 16, 2020

5 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
September 167:53 AM CDTEF0Calhoun, FL9.950$1,000
September 164:30 PM EDTEF0Cook, GA2.250
September 164:46 PM EDTEF0Brooks, GA5.350
September 165:06 PM EDTEF0Thomas, GA2.350
September 167:33 PM EDTEF1Ware, GA0.2200$40,000

What this means

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.

Sources

NOAA Storm Prediction Center tornado database, 1950-2025, the official record kept by NOAA's Storm Prediction Center.