Tornadoes · United States · Texas · 1976

F2 tornado, Polk County, Texas, March 30, 1976

This F2 tornado ran 26.7 miles across Polk County on March 30, 1976, touching down at 1:20 PM CST and reaching 1,300 yards wide. It killed nobody, and did $50,000 to $500,000 of property damage.

The rating scale

Tracks are drawn in the color of the rating. The Fujita scale rates the damage rather than measuring the wind: the speeds are what that damage is taken to imply.

  1. F040 to 72 mph

    Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.

  2. F173 to 112 mph

    Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.

  3. F2113 to 157 mphthis tornado

    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. F3158 to 206 mph

    Severe damage. Whole stories of well-built houses destroyed, large buildings badly damaged, trains overturned, trees debarked, heavy cars lifted and thrown.

  5. F4207 to 260 mph

    Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.

  6. F5261 to 318 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
F2
Date
March 30, 1976
Touchdown
1:20 PM CST (19:20 UTC)
Path length
26.7 miles (43.0 km)
Path width
1,300 yards (1189 m)
Deaths
0
Injuries
0
Property damage
$50,000 to $500,000
County
Polk County
Touchdown point
30.820, -94.820
Lift-off point
31.120, -94.530
Record number
218

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.

Longview/Gregg, TX (KGGG), 12:00Z

7.3 hours before the tornado, 154 km from the path. March 30, 1976.

Skew-T log-pSkew-T log-p diagram, Longview/Gregg, TX at 12:00Z on 1976-03-30Temperature 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 -14590, lifted condensation level 2530 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, Longview/Gregg, TX at 12:00Z on 1976-03-30The 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 43 square meters per square second, 0 to 6 km bulk shear 53 knots.1939587897117Sfc1 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
-14590 J/kg
Surface CAPE
0 J/kg
Mixed-layer LCL
2530 m above ground
0-6 km bulk shear
53 kt
0-1 km bulk shear
5 kt
0-1 km storm-relative helicity
43 m²/s²
0-3 km storm-relative helicity
508 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.5
0-3 km lapse rate
3.1 K/km

Open this sounding in Storm Lab

Longview/Gregg, TX (KGGG), 00:00Z

4.7 hours after it, 154 km from the path. March 31, 1976.

Skew-T log-pSkew-T log-p diagram, Longview/Gregg, TX at 00:00Z on 1976-03-31Temperature 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 -14664, lifted condensation level 1420 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, Longview/Gregg, TX at 00:00Z on 1976-03-31The 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 4 square meters per square second, 0 to 6 km bulk shear 64 knots.1939587897117Sfc1 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
-14664 J/kg
Surface CAPE
0 J/kg
Mixed-layer LCL
1420 m above ground
0-6 km bulk shear
64 kt
0-1 km bulk shear
3 kt
0-1 km storm-relative helicity
4 m²/s²
0-3 km storm-relative helicity
145 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1
0-3 km lapse rate
3.9 K/km

Open this sounding in Storm Lab

The surface observations

Lufkin/Angelina Co. (LFK), 30 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
17:00 UTC4736360° 10 kt151014.6TSRA
18:00 UTC5350360° 9 kt1014.6-SHRA
19:00 UTC5448360° 12 kt1012.9
19:19 UTC360° 10 kt1013.2
19:35 UTC230° 15 kt311016.3
20:00 UTC524810° 5 kt1014.9TSRA

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

This ground now

The live radar over the trackEvery 1976 tornado in TexasEvery tornado in Texas since 1950Warnings in force in Texas nowThe forecast where you are

The other tornadoes of March 30, 1976

18 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
March 302:32 AM CSTF1Kerr, TX1.01008$50,000 to $500,000
March 302:40 AM CSTF2Kendall, TX15.2200$500,000 to $5 million
March 303:20 AM CSTF2Hays, TX1.0100$5,000 to $50,000
March 303:30 AM CSTF2Hays, TX2.52001$50,000 to $500,000
March 303:45 AM CSTF0Travis, TX10.41008$50,000 to $500,000
March 305:00 AM CSTF1Burleson, TX6.6200$500,000 to $5 million
March 301:40 PM ESTF1Clare, MI2.067$5,000 to $50,000
March 301:00 PM CSTF2Polk, TX22.11,3001$500,000 to $5 million
March 302:10 PM ESTF3Gladwin, MI11.410010under $50
March 301:25 PM CSTF0Wilcox, AL0.250$5,000 to $50,000
March 302:40 PM ESTF3Ogemaw, MI6.411717$50,000 to $500,000
March 301:45 PM CSTF1Angelina, TX0.110
March 301:50 PM CSTF1Madison, MS3.0100
March 302:00 PM CSTF2Vernon Parish, LA35.950$50,000 to $500,000
March 303:05 PM ESTF1Iosco, MI2.583$5,000 to $50,000
March 303:20 PM ESTF2Alcona, MI4.9150under $50
March 302:45 PM CSTF2Vernon Parish, LA42.1773$50,000 to $500,000
March 304:35 PM CSTF3Jefferson, MS31.71,583$50,000 to $500,000

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.