EF1 tornado, Willamar, Texas, October 30, 2015

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

October 30, 2015

Touchdown

6:36 AM CDT (11:36 UTC)

Lifted

6:38 AM CDT (11:38 UTC)

On the ground

2 minutes

Path length

0.7 miles (1.0 km)

Path width

25 yards (23 m)

Deaths

0

Injuries

0

Property damage

$50,000

County

Willacy County

Touchdown point

26.365, -97.672

Lift-off point

26.374, -97.674

Record number

1510300536-01

16 damage points were recorded along this path by NWS BRO, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF1. The highest wind the damage implies is 86 mph.

• Speed based on higher wind speed collected by Davis Pro 2 instrument less than 1 mile north.
• Well built structure but unknown how well aluminum/tin roof was fastened to it.
• Tin/aluminum panels along thin track to the north/northwest of the outbuilding
• Unable to see additional tree damage; water depth too great to cross safely. Speed raised based on nearby observation from Davis Pro 2 station.

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

A wave of upper level energy, arriving well ahead of a vigorous trough of surface and high level low pressure, acted on a very unstable airmass that was also conducive to producing rotating thunderstorms during the pre���dawn hours of October 30th to produce a mini���supercell thunderstorm in northern Cameron County, which raced northward through Willacy and into Kenedy County. The thunderstorm, spawned a brief tornado around Los Coyotes just after 630 AM, which moved to the north���northwest and quickly dissipated before reaching Raymondville. A second tornado formed to its east, at a Cotton producing facility in Willamar.

A survey team revealed peak winds ranging from 74 to 86 mph for the Los Coyotes Tornado. The 86 mph winds were measured by a property owner���s weather station, whose information was considered viable based on visual evidence of damage and radar depiction of velocity in the core of the circulation, which exceeded 60 knots (70 mph). Damage in Los Coyotes was to a few barns and outbuildings, as well as uprooted and snapped trees. Emergency Management noted seven power poles were leaning or down, but had been repaired by the time to survey was conducted on October 31.

The survey team estimated peak winds between 70 and 75 mph for the Willamar tornado. Primary damage was a cotton seed container/holder that was lifted from moorings into concrete block. The lack of material in the metal container allowed winds to get underneath and lift; pressures on the minimally anchored columns caused the damage. Other damage included a portion of roof peeled back from a mobile home, where a 12 year old child was injured by flying debris and taken to a local hospital in Harlingen for observation. The tin roof damage revealed poor connections to rotted wood. Minor damage to trees along Farm to Market Road 1420 was also noted.

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

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 Storm Prediction Center had this point in a Marginal Risk. The outlook in force was issued at 05:27 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.

Harlingen International Airport (HRL), 16 km from the path, in the two hours either side.

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

The Brownsville radar (KBRO), 57 km away, was scanning. The volume nearest the touchdown began at 11:34 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 2015 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.