Tornadoes · United States · Nebraska · 1993

F1 tornado, Pierce County, Nebraska, August 29, 1993

This F1 tornado ran 1.0 miles across Pierce County on August 29, 1993, touching down at 7:05 PM CDT and reaching 50 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 mphthis tornado

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

  3. F2113 to 157 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. 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
F1
Date
August 29, 1993
Touchdown
7:05 PM CDT (00:05 UTC)
Path length
1.0 miles (1.6 km)
Path width
50 yards (46 m)
Deaths
0
Injuries
0
Property damage
$50,000 to $500,000
County
Pierce County
Touchdown point
42.280, -97.530
Record number
1019

The warnings

7 minutes of warning. NWS LBF issued a tornado warning for this county at 23:58 UTC, 7 minutes before the tornado touched down, in force until 00:30 UTC.

Issued (UTC)ExpiredProductOffice
23:58 UTC00:30 UTCTornado WarningLBF
00:30 UTC01:15 UTCSevere Thunderstorm WarningLBF
03:00 UTC07:00 UTCFlash Flood WarningLBF

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 Slight Risk. The outlook in force was issued at 06:10 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.

Omaha, NE (KOAX), 00:00Z

0.1 hours before the tornado, 144 km from the path. August 30, 1993.

Skew-T log-pSkew-T log-p diagram, Omaha, NE at 00:00Z on 1993-08-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 4054 joules per kilogram, CIN -7, lifted condensation level 760 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, Omaha, NE at 00:00Z on 1993-08-30The 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 172 square meters per square second, 0 to 6 km bulk shear 29 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
4054 J/kg
Mixed-layer CIN
-7 J/kg
Surface CAPE
5095 J/kg
Mixed-layer LCL
760 m above ground
0-6 km bulk shear
29 kt
0-1 km bulk shear
22 kt
0-1 km storm-relative helicity
172 m²/s²
0-3 km storm-relative helicity
263 m²/s²
Significant tornado parameter
4.0
Supercell composite
22.5
0-3 km lapse rate
6.3 K/km

Open this sounding in Storm Lab

Omaha, NE (KOAX), 12:00Z

11.9 hours after it, 144 km from the path. August 30, 1993.

Skew-T log-pSkew-T log-p diagram, Omaha, NE at 12:00Z on 1993-08-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 219 joules per kilogram, CIN -21, lifted condensation level 716 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 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, Omaha, NE at 12:00Z on 1993-08-30The 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 -65 square meters per square second, 0 to 6 km bulk shear 40 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
219 J/kg
Mixed-layer CIN
-21 J/kg
Surface CAPE
152 J/kg
Mixed-layer LCL
716 m above ground
0-6 km bulk shear
40 kt
0-1 km bulk shear
17 kt
0-1 km storm-relative helicity
-65 m²/s²
0-3 km storm-relative helicity
-126 m²/s²
Significant tornado parameter
-0.1
Supercell composite
-0.4
0-3 km lapse rate
4.9 K/km

Open this sounding in Storm Lab

This ground now

The live radar over the trackEvery 1993 tornado in NebraskaEvery tornado in Nebraska since 1950Warnings in force in Nebraska nowThe forecast where you are

The other tornadoes of August 29, 1993

7 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
August 2911:40 AM MSTF0Cochise, AZ0.110
August 294:30 PM PDTF1Imperial, CA0.110
August 296:30 PM CDTF1Sherman, NE6.023$5,000 to $50,000
August 297:20 PM CDTF0Sully, SD0.220
August 297:25 PM CDTF0Sully, SD0.220
August 297:45 PM CDTF0Sully, SD0.220
August 299:15 PM CDTF1Dixon, NE0.550$5,000 to $50,000

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.