EF1 tornado, Notrees, Texas, September 17, 2016

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

September 17, 2016

Touchdown

7:13 PM CDT (00:13 UTC)

Lifted

7:35 PM CDT (00:35 UTC)

On the ground

22 minutes

Path length

5.9 miles (9.4 km)

Path width

400 yards (366 m)

Deaths

0

Injuries

0

Property damage

$30,000

County

Ector County

Touchdown point

32.095, -102.806

Lift-off point

32.026, -102.747

Record number

1609171813-01

20 damage points were recorded along this path by NWS MAF, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF1. The highest wind the damage implies is 105 mph.

• single power pole snapped halfway
• top of cylinder popped off
• numerous power poles broken at base along with debris scattered across field
• small tin building appears to have been moved

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

An upper level disturbance moved over the area, and a lingering frontal boundary was across the Permian Basin. Upper level lift associated with an area of intense winds aloft moved over the region. There was good wind shear, moisture, and instability across West Texas and southeast New Mexico. Two other boundaries were moving toward the area and possibly collided with the initial boundary. These conditions combined to create good lift in the atmosphere which resulted in widespread thunderstorms with large hail across southeast New Mexico and the Permian Basin. The wind shear created spin in the atmosphere which allowed for tornadoes to develop in the Permian Basin and southeast New Mexico. Deep moisture across the area resulted in flash flooding that developed in the Permian Basin.

A supercell thunderstorm developed over Andrews County during the evening hours of September 17th. This storm encountered a stationary boundary and began moving southeast. The storm began to form a hook echo at 6:30 pm CDT as it moved toward Highway 115 in southwest Andrews County. Eyewitness reports from storm chasers and spotters in the area indicate that the initial tornado began at 7:13 pm CDT near the intersection of Andrews, Winkler and Ector Counties. Videos taken of the tornado show it touching down and lifting several times before eventually staying on the ground for several minutes over far northwest portions of Ector County. The tornado moved south southeastward across open fields of rural Ector County just west of FM 181. The damage assessment team looked at several different indicators to determine tornado intensity. The tornado snapped several electrical power poles and overturned a tank battery along its path. These damage indicators suggest EF1 intensity with wind speeds estimated at 90 to 105 mph. Near the end of the life cycle of the EF1 tornado, a weak anticyclonic circulation developed on the forward flank of the supercell around 7:25 pm CDT. This circulation moved southwest to the west of FM 181 and dissipated around 7:35 pm CDT. Storm chasers and spotters identified this funnel looking north from Goldsmith around 7:30 pm CDT. There was no evidence of damage or reports of the funnel cloud touching down. The tornado path width was estimated and the cost of damage is a very rough estimate.

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

32 minutes of warning. NWS MAF issued a tornado warning for this county at 23:41 UTC, 32 minutes before the tornado touched down, in force until 00:15 UTC.

The county was under a severe thunderstorm watch, issued at 20:02 UTC and running to 03:00 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 0.02 chance of a tornado within 25 miles. The outlook in force was issued at 19:59 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 Midland/Odessa radar (KMAF), 57 km away, was scanning. The volume nearest the touchdown began at 00:12 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 2016 tornado in TexasEvery tornado in Texas since 1950Warnings in force in Texas nowThe forecast where you are

6 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.