Tornadoes · United States · Alabama · 2020

Unrated tornado, Hobbs Is, Alabama, August 23, 2020

This Unrated tornado ran 0.1 miles across Madison County on August 23, 2020, touching down at 12:13 PM CDT 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 mph

    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. Unratedthis tornado

    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
Unrated
Date
August 23, 2020
Touchdown
12:13 PM CDT (17:13 UTC)
Lifted
12:21 PM CDT (17:21 UTC)
On the ground
8 minutes
Path length
0.1 miles (0.2 km)
Path width
50 yards (46 m)
Deaths
0
Injuries
0
County
Madison County
Touchdown point
34.550, -86.550
Lift-off point
34.551, -86.548
Record number
2008231113-01

What the Weather Service recorded

A small shower developed during the midday hour near the Tennessee River at Ditto Landing on the Madison-Marshall County line. The shower produced a funnel cloud that descended at 1107 pm CST, and touched down as a tornado and/or waterspout from around 1113 pm CST and lifting around 1125 pm CST. The tornado was observed by a local research meteorologist at Ditto Landing who called in the report to the National Weather Service. The tornado from his viewpoint touched down at Hobbs Island, and possibly could have crossed onto the water as well. However, no damage was reported. Two other mesonet weather cameras also recorded the tornado from two different vantage points, one at the University of Alabama in Huntsville Severe Weather Institute - Radar and Lightning Laboratories (SWIRLL) and the Baron Critical Weather Institute camera in New Hope.

A local research meteorologist located at Ditto Landing witnessed a tornado and possibly a waterspout at times on and adjacent to Hobbs Island along the Tennessee River. Mesonet cameras including one from the University of Alabama in Hunstville at the Severe Weather Institute, Radar and Lightning Laboratories (SWIRLL) captured the event. No damages were reported.

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

The warnings

No tornado warning for this county appears in the archive as in force at the moment the tornado touched down.

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 General Thunderstorms Risk. The outlook in force was issued at 16:39 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.

Birmingham, AL (KBMX), 12:00Z

5.2 hours before the tornado, 154 km from the path. August 23, 2020.

Skew-T log-pSkew-T log-p diagram, Birmingham, AL at 12:00Z on 2020-08-23Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 607 joules per kilogram, CIN -20, lifted condensation level 539 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°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, Birmingham, AL at 12:00Z on 2020-08-23The 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 75 square meters per square second, 0 to 6 km bulk shear 23 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
607 J/kg
Mixed-layer CIN
-20 J/kg
Surface CAPE
539 J/kg
Mixed-layer LCL
539 m above ground
0-6 km bulk shear
23 kt
0-1 km bulk shear
11 kt
0-1 km storm-relative helicity
75 m²/s²
0-3 km storm-relative helicity
115 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.3
0-3 km lapse rate
5.1 K/km

Open this sounding in Storm Lab

Birmingham, AL (KBMX), 00:00Z

6.8 hours after it, 154 km from the path. August 24, 2020.

Skew-T log-pSkew-T log-p diagram, Birmingham, AL at 00:00Z on 2020-08-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 481 joules per kilogram, CIN -8, lifted condensation level 1416 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°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, Birmingham, AL at 00:00Z on 2020-08-24The 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 8 square meters per square second, 0 to 6 km bulk shear 15 knots.19395878Sfc1 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
481 J/kg
Mixed-layer CIN
-8 J/kg
Surface CAPE
1549 J/kg
Mixed-layer LCL
1416 m above ground
0-6 km bulk shear
15 kt
0-1 km bulk shear
10 kt
0-1 km storm-relative helicity
8 m²/s²
0-3 km storm-relative helicity
35 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
7.3 K/km

Open this sounding in Storm Lab

The radar

The Northeast Alabama radar (KHTX), 60 km away, was scanning. The volume nearest the touchdown began at 17:10 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
17:13 UTCTORNADO5 Wsw Owens CrossroadsMadison, ALA METEOROLOGIST WITNESSED A TORNADO/LANDSPOUT ON HOBBS ISLAND ADJACENT TO THE TENNESSEE RIVER. OTHER MESONET CAMERAS INCLUDING ONE FROM UAH WHERE THE NWS OFFICE IS LOCATED ALSO RECORDED THIS, STARTING AT APPROXIMATELY 12

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 AlabamaEvery tornado in Alabama since 1950Warnings in force in Alabama nowThe forecast where you are

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.