EF1 tornado, Helotes, Texas, May 24, 2020

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

May 24, 2020

Touchdown

8:11 PM CDT (01:11 UTC)

Lifted

8:12 PM CDT (01:12 UTC)

On the ground

1 minutes

Path length

0.5 miles (0.8 km)

Path width

50 yards (46 m)

Deaths

0

Injuries

0

Property damage

$500,000

County

Bexar County

Touchdown point

29.527, -98.705

Lift-off point

29.533, -98.699

Record number

2005241911-01

7 damage points were recorded along this path by NWS EWX, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF1. The highest wind the damage implies is 100 mph.

• Fence down, eyewitness of funnel

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

An upper level shortwave trough moved through West Texas and interacted with a dryline to generate thunderstorms. The airmass was strongly unstable with only modest vertical wind shear and high precipitable water. Storms evolved into a line as they moved across South Central Texas producing large hail, damaging wind gusts, and one tornado. They also produced heavy rain that led to flash flooding.

An NWS damage survey concluded that a small EF1 tornado touched down in the Wildhorse subdivision, between Loop 1604 and the Government Canyon State Natural area on the west side of Bexar County. A large severe storm was moving northeast through the area just after 7 PM when it appears a tornado developed near the Flying Fury Dr. cul-de-sac and neighborhood drainage ditch. There was minor damage on Flying Fury with substantial roof damage to several homes on the east side of Palomino Path as the tornado moved northeast. Several of the homes had broken windows, large sections of roof lifted off, along with puncture marks from flying debris on many of the exterior walls. The maximum winds were reached at this location and were estimated to be 100 mph. The tornado continued moving northeast, taking down a fence at the end of Palomino Path before likely dissipating near the Wildhorse HOA Sports Park and open field/drainage area.

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

7 minutes of warning. NWS EWX issued a tornado warning for this county at 01:04 UTC, 7 minutes before the tornado touched down, in force until 01:30 UTC.

The county was under a severe thunderstorm watch, issued at 23:04 UTC and running to 03:55 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 00:48 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.

Kelly Afb (SKF), 20 km from the path, in the two hours either side.

From the Iowa Environmental Mesonet's archive of airport observations.

The Austin/San Antonio radar (KEWX), 68 km away, was scanning. The volume nearest the touchdown began at 01:10 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.

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 2020 tornado in TexasEvery tornado in Texas since 1950Warnings in force in Texas nowThe forecast where you are

2 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.