Tornadoes · United States · Texas · 2017
EF1 tornado, Evadale to Buna, Texas, December 20, 2017
From Evadale to Buna, this EF1 tornado ran 4.0 miles across Jasper County on December 20, 2017, touching down at 1:37 AM CST and reaching 250 yards wide. It killed nobody, and did $30,000 of property damage.
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.
EF065 to 85 mph
Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.
EF186 to 110 mphthis tornado
Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.
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.
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.
EF4166 to 200 mph
Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.
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.
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
- EF1
- Date
- December 20, 2017
- Touchdown
- 1:37 AM CST (07:37 UTC)
- Lifted
- 1:42 AM CST (07:42 UTC)
- On the ground
- 5 minutes
- Path length
- 4.0 miles (6.4 km)
- Path width
- 250 yards (229 m)
- Deaths
- 0
- Injuries
- 0
- Property damage
- $30,000
- County
- Jasper County
- Touchdown point
- 30.276, -93.948
- Lift-off point
- 30.294, -93.885
- Record number
- 1712200137-01
The damage survey
18 damage points were recorded along this path by NWS LCH, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF1. The highest wind the damage implies is 107 mph.
Survey points are preliminary and are the raw material the published rating was built from. Source: NWS Damage Assessment Toolkit.
What the Weather Service recorded
A weak cold front and a short wave moved through the region during the early morning of the 20th. One tornado developed.
Many trees were downed around the community of Gist, along the Jasper-Newton county line. Some barns and a few roofs to homes were damaged. The maximum wind speed in the tornado was estimated at 100 mph.
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 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.
Lake Charles Mun, LA (KLCH), 00:00Z
7.6 hours before the tornado, 71 km from the path. December 20, 2017.
- Mixed-layer CAPE
- 888 J/kg
- Mixed-layer CIN
- -6 J/kg
- Surface CAPE
- 1033 J/kg
- Mixed-layer LCL
- 503 m above ground
- 0-6 km bulk shear
- 53 kt
- 0-1 km bulk shear
- 18 kt
- 0-1 km storm-relative helicity
- 118 m²/s²
- 0-3 km storm-relative helicity
- 152 m²/s²
- Significant tornado parameter
- 0.7
- Supercell composite
- 3.7
- 0-3 km lapse rate
- 4.1 K/km
Lake Charles Mun, LA (KLCH), 12:00Z
4.4 hours after it, 71 km from the path. December 20, 2017.
- Mixed-layer CAPE
- 0 J/kg
- Mixed-layer CIN
- -80207 J/kg
- Surface CAPE
- 0 J/kg
- Mixed-layer LCL
- 902 m above ground
- 0-6 km bulk shear
- 52 kt
- 0-1 km bulk shear
- 22 kt
- 0-1 km storm-relative helicity
- -147 m²/s²
- 0-3 km storm-relative helicity
- -73 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
- 0-3 km lapse rate
- 4.3 K/km
The surface observations
Orange (ORG), 26 km from the path, in the two hours either side.
| Time (UTC) | Temp (°F) | Dew point (°F) | Wind | Gust (kt) | Pressure (mb) | Weather |
|---|---|---|---|---|---|---|
| 05:55 UTC | 71.6 | 71.6 | 210° 12 kt | 1015.9 | VCTSRA | |
| 06:15 UTC | 71.4 | 71.4 | 200° 10 kt | 15 | 1015.2 | -VCTSRA |
| 06:35 UTC | 71.2 | 71.2 | 210° 9 kt | 1015.2 | BR | |
| 06:55 UTC | 71.6 | 71.6 | 200° 9 kt | 15 | 1014.2 | VCTS |
| 07:15 UTC | 71.6 | 71.6 | 200° 11 kt | 16 | 1013.9 | VCTS BR |
| 07:35 UTC | 72 | 72 | 210° 13 kt | 20 | 1013.5 | VCTS |
| 07:55 UTC | 73 | 73 | 220° 12 kt | 25 | 1014.6 | TS |
| 08:15 UTC | 72.5 | 72 | 270° 15 kt | 30 | 1015.6 | +TSRA |
| 08:35 UTC | 66.4 | 66.2 | 240° 6 kt | 1015.2 | -TSRA | |
| 08:55 UTC | 67 | 67 | 230° 4 kt | 1015.2 | -VCTSDZ | |
| 09:15 UTC | 67 | 67 | 250° 3 kt | 1015.6 | VCTS | |
| 09:35 UTC | 67 | 67 | 0° 0 kt | 1015.2 |
From the Iowa Environmental Mesonet's archive of airport observations.
The radar
The Lake Charles radar (KLCH), 70 km away, was scanning. The volume nearest the touchdown began at 07:36 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) | Report | Where | County | Remark |
|---|---|---|---|---|
| 07:41 UTC | TORNADO | Gist | Jasper, TX | A TORNADO TOUCHED DOWN NEAR GIST, WHERE AROUND 20 TREES WERE BLOWN DOWN OR SNAPPED. |
From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.
This ground now
The live radar over the trackEvery 2017 tornado in TexasEvery tornado in Texas since 1950Warnings in force in Texas nowThe forecast where you are
The other tornadoes of December 20, 2017
6 more were confirmed in the United States that day.
| Date | Time | Rating | Where | Path (mi) | Width (yd) | Deaths | Injuries | Damage |
|---|---|---|---|---|---|---|---|---|
| December 20 | 1:02 AM CST | EF1 | Jackson Parish, LA | 0.9 | 110 | $75,000 | ||
| December 20 | 1:59 AM CST | EF1 | Calcasieu Parish, LA | 3.0 | 600 | $15,000 | ||
| December 20 | 2:17 AM CST | EF1 | Calcasieu Parish, LA | 4.7 | 600 | $250,000 | ||
| December 20 | 6:35 AM CST | EF1 | Walthall, MS | 9.9 | 80 | |||
| December 20 | 10:40 AM CST | EF0 | Randolph, AL | 3.2 | 16 | |||
| December 20 | 1:15 PM EST | EF0 | Meriwether, GA | 3.2 | 125 | $30,000 |
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.