Tornadoes · United States · Texas · 2019

EF1 tornado, Alta Vista, Texas, April 7, 2019

This EF1 tornado ran 0.7 miles across Harris County on April 7, 2019, touching down at 12:42 PM CDT and reaching 50 yards wide. It killed nobody, and did $150,000 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.

  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.

The record

Rating
EF1
Date
April 7, 2019
Touchdown
12:42 PM CDT (17:42 UTC)
Lifted
12:44 PM CDT (17:44 UTC)
On the ground
2 minutes
Path length
0.7 miles (1.2 km)
Path width
50 yards (46 m)
Deaths
0
Injuries
0
Property damage
$150,000
County
Harris County
Touchdown point
29.650, -95.202
Lift-off point
29.658, -95.200
Record number
1904071142-01

The damage survey

9 damage points were recorded along this path by NWS HGX, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF0. The highest wind the damage implies is 80 mph.

  • Numerous power poles snapped and laid down (6 or so along Shaver).
  • pointing north northwest. Also downed power line pointing north.
  • Tree tops snapped off deposited in different directions. Neighbor observed winds shift in direction.
  • Large branches felled toward the south.

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 storm system moved across the area during the day and produced large hail, damaging winds and tornadoes.

This EF-1 tornado snapped numerous street poles and destroyed a building when its west facing wall collapsed. There was considerable tree damage with large limbs stripped and trunks snapped.

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. One was issued for the county at another hour that day.

The county was under a severe thunderstorm watch, issued at 12:11 UTC and running to 20:00 UTC.

Issued (UTC)ExpiredProductOffice
12:11 UTC20:00 UTCSevere Thunderstorm WatchHGX
16:23 UTC17:15 UTCSevere Thunderstorm WarningHGX
17:04 UTC17:45 UTCSevere Thunderstorm WarningHGX
17:35 UTC18:00 UTCSevere Thunderstorm WarningHGX
17:44 UTC18:00 UTCTornado WarningHGX
17:58 UTC18:45 UTCSevere Thunderstorm WarningHGX
18:35 UTC19:05 UTCSevere Thunderstorm WarningHGX

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 Enhanced Risk, with a 0.02 chance of a tornado within 25 miles. The outlook in force was issued at 16:13 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.

Lake Charles Mun, LA (KLCH), 12:00Z

5.7 hours before the tornado, 200 km from the path. April 7, 2019.

Skew-T log-pSkew-T log-p diagram, Lake Charles Mun, LA at 12:00Z on 2019-04-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 2596 joules per kilogram, CIN -7, lifted condensation level 449 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°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, Lake Charles Mun, LA at 12:00Z on 2019-04-07The 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 39 square meters per square second, 0 to 6 km bulk shear 26 knots.19395878Sfc1 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
2596 J/kg
Mixed-layer CIN
-7 J/kg
Surface CAPE
2954 J/kg
Mixed-layer LCL
449 m above ground
0-6 km bulk shear
26 kt
0-1 km bulk shear
12 kt
0-1 km storm-relative helicity
39 m²/s²
0-3 km storm-relative helicity
124 m²/s²
Significant tornado parameter
0.5
Supercell composite
2.4
0-3 km lapse rate
4.5 K/km

Open this sounding in Storm Lab

Lake Charles Mun, LA (KLCH), 00:00Z

6.3 hours after it, 200 km from the path. April 8, 2019.

Skew-T log-pSkew-T log-p diagram, Lake Charles Mun, LA at 00:00Z on 2019-04-08Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 0 joules per kilogram, CIN -43443, lifted condensation level 2166 meters above ground. Wind barbs in knots down the right edge.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°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, Lake Charles Mun, LA at 00:00Z on 2019-04-08The 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 234 square meters per square second, 0 to 6 km bulk shear 36 knots.193958Sfc1 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
0 J/kg
Mixed-layer CIN
-43443 J/kg
Surface CAPE
2 J/kg
Mixed-layer LCL
2166 m above ground
0-6 km bulk shear
36 kt
0-1 km bulk shear
36 kt
0-1 km storm-relative helicity
234 m²/s²
0-3 km storm-relative helicity
299 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
4.2 K/km

Open this sounding in Storm Lab

The radar

The Houston radar (KHGX), 23 km away, was scanning. The volume nearest the touchdown began at 17:43 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
17:10 UTCTSTM WND DMGSugar LandFort Bend, TXTREES WERE BLOWN DOWN.
17:16 UTCTSTM WND DMGMissouri CityFort Bend, TXTREES AND POWER LINES DOWN.
17:17 UTCTSTM WND DMGBellaireHarris, TXNUMEROUS REPORTS OF DOWNED TREE LIMBS IN AND AROUND THE BELLAIRE AND WEST UNIVERSITY PLACE (WEST 610 LOOP) AREA.
17:30 UTCTSTM WND DMGHoustonHarris, TXOVER 90 REPORTS OF TREE DAMAGE.
17:35 UTCTSTM WND DMG1 Sw Southampton PlaceHarris, TXSTREET AND BUSINESS SIGN DAMAGE, ALONG WITH TREE DAMAGE IN AND AROUND RICE VILLAGE.
17:42 UTCTORNADOArlington HeightsHarris, TXEF-1 TORNADO TOUCHED DOWN ALONG SHAVER STREET JUST SOUTH OF FAIRMONT PARKWAY. ONE BUILDING WAS DESTROYED WHEN ONE OF ITS WEST WALLS COLLAPSED. SEVERAL STREET LIGHT POLES WERE SNAPPED. BADLY DAMAGED TREES IN A NORTHEASTER
17:43 UTCTSTM WND DMG1 Ese DickinsonGalveston, TXTREES WERE BLOWN DOWN.
17:47 UTCMARINE TSTM WIND 411 Sw Taylor Lake VillagHarris, TXMEASURED AT WEATHERFLOW SITE XCLP
17:53 UTCTSTM WND DMGTexas CityGalveston, TXTHUNDERSTORM WINDS DOWNED TREES.
17:58 UTCTSTM WND DMGHighlandsHarris, TXTREES AND POWER LINES WERE DOWNED.
18:15 UTCTSTM WND DMG2 Ne Bolivar BeachGalveston, TXSTORM WINDS FLIPPED OVER SOME TRAVEL TRAILERS.

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

This ground now

The live radar over the trackEvery 2019 tornado in TexasEvery tornado in Texas since 1950Warnings in force in Texas nowThe forecast where you are

The other tornadoes of April 7, 2019

6 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
April 77:24 AM CDTEF0Bee, TX0.630$1.3 million
April 712:58 PM CDTEF0Montgomery, TX0.030$6,000
April 76:01 PM CDTEF1Wilkinson, MS2.2175
April 77:45 PM CDTEF0Ascension Parish, LA2.050$50,000
April 78:04 PM CDTEF1Saint Helena Parish, LA1.575
April 78:19 PM CDTEF0Jefferson Parish, LA2.650

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.