Tornadoes · United States · Texas · 2009

EF0 tornado, San Perlita, Texas, September 22, 2009

This EF0 tornado ran 0.0 miles across Willacy County on September 22, 2009, touching down at 4:30 PM CDT and reaching 10 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 mphthis tornado

    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. 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
EF0
Date
September 22, 2009
Touchdown
4:30 PM CDT (21:30 UTC)
Lifted
4:40 PM CDT (21:40 UTC)
On the ground
10 minutes
Path length
0.0 miles (0.0 km)
Path width
10 yards (9 m)
Deaths
0
Injuries
0
County
Willacy County
Touchdown point
26.460, -97.620
Lift-off point
26.460, -97.620
Record number
0909221530-01

What the Weather Service recorded

A cold front moved through The Rio Grande Valley September 22 producing numerous thunderstorms across Deep South Texas during the afternoon and early evening. Rainfall occurred across Starr, Jim Hogg, eastern Hidalgo, and western Cameron County through western Kenedy County as well as along the immediate coast from the Laguna Madre to Padre and South Padre Islands. The thunderstorms produced flooding in some locations and high winds across portions of the marine areas.

KRGV Television station reported that the public had reported a brief touchdown of a tornado near the town of Willamar. No damage was reported and there weren���t any homes in the area.

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

The warnings

19 minutes of warning. NWS BRO issued a tornado warning for this county at 21:11 UTC, 19 minutes before the tornado touched down, in force until 22:15 UTC.

Issued (UTC)ExpiredProductOffice
20:36 UTC22:30 UTCFlood AdvisoryBRO
21:00 UTC03:23 UTCFlash Flood WatchBRO
21:11 UTC22:15 UTCTornado WarningBRO
22:17 UTC23:45 UTCSevere Thunderstorm WarningBRO
22:23 UTC23:45 UTCFlood AdvisoryBRO

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 23:36 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.

Brownsville Intl, TX (KBRO), 12:00Z

9.5 hours before the tornado, 66 km from the path. September 22, 2009.

Skew-T log-pSkew-T log-p diagram, Brownsville Intl, TX at 12:00Z on 2009-09-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 3010 joules per kilogram, CIN -7, lifted condensation level 668 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°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, Brownsville Intl, TX at 12:00Z on 2009-09-22The 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 -17 square meters per square second, 0 to 6 km bulk shear 12 knots.1939Sfc1 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
3010 J/kg
Mixed-layer CIN
-7 J/kg
Surface CAPE
2213 J/kg
Mixed-layer LCL
668 m above ground
0-6 km bulk shear
12 kt
0-1 km bulk shear
17 kt
0-1 km storm-relative helicity
-17 m²/s²
0-3 km storm-relative helicity
5 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
4.7 K/km

Open this sounding in Storm Lab

Brownsville Intl, TX (KBRO), 00:00Z

2.5 hours after it, 66 km from the path. September 23, 2009.

Skew-T log-pSkew-T log-p diagram, Brownsville Intl, TX at 00:00Z on 2009-09-23Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 3266 joules per kilogram, CIN -14, lifted condensation level 936 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°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, Brownsville Intl, TX at 00:00Z on 2009-09-23The 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 23 square meters per square second, 0 to 6 km bulk shear 24 knots.1939Sfc1 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
3266 J/kg
Mixed-layer CIN
-14 J/kg
Surface CAPE
3483 J/kg
Mixed-layer LCL
936 m above ground
0-6 km bulk shear
24 kt
0-1 km bulk shear
5 kt
0-1 km storm-relative helicity
23 m²/s²
0-3 km storm-relative helicity
12 m²/s²
Significant tornado parameter
0.1
Supercell composite
0.8
0-3 km lapse rate
7.2 K/km

Open this sounding in Storm Lab

The surface observations

Harlingen International Airport (HRL), 26 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
19:52 UTC9275170° 10 kt201009.8
20:52 UTC9273170° 10 kt1009.1
21:52 UTC9171150° 10 kt171009.5
22:28 UTC78.871.650° 26 kt331010.8
22:52 UTC767330° 19 kt271011.5VCTS

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

The radar

The Brownsville radar (KBRO), 64 km away, was scanning. The volume nearest the touchdown began at 21:28 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
21:00 UTCMARINE TSTM WIND 42Port MansfieldWillacy, TXPORT MANSFIELD HARBOR MASTER REPORTED WIND GUST OF 42 MPH WITH THUNDERSTORM.
21:30 UTCTORNADOWillamarWillacy, TXKRGV RELAYED PUBLIC REPORT OF BRIEF TORNADO TOUCHDOWN NEAR THE TOWN OF WILLAMAR. NO DAMAGE REPORTED. NO HOMES WERE NEAR THE TOUCHDOWN LOCATIONS.
23:18 UTCMARINE TSTM WIND 396 S Buena VistaCameron, TX

From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.

This ground now

The live radar over the trackEvery 2009 tornado in TexasEvery tornado in Texas since 1950Warnings in force in Texas 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.