Tornadoes · United States · Nebraska · 1994

F1 tornado, Bloomfield to To 4 Ene Bloomfield, Nebraska, April 25, 1994

From Bloomfield to To 4 Ene Bloomfield, this F1 tornado ran 7.0 miles across Knox County on April 25, 1994, touching down at 5:45 PM CDT and reaching 200 yards wide. It killed nobody and injured 1, 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
April 25, 1994
Touchdown
5:45 PM CDT (22:45 UTC)
Path length
7.0 miles (11.3 km)
Path width
200 yards (183 m)
Deaths
0
Injuries
1
Property damage
$50,000 to $500,000
County
Knox County
Touchdown point
42.530, -97.630
Lift-off point
42.630, -97.550
Record number
165

What the Weather Service recorded

A small tornado started on the southeast fringes of town. It picked up a fiberglass storage tank east of town and carried it north for over a mile. The tank was deposited onto a truck, bounced off of a car and then into a garage. The truck was totalled, the car damaged and the garaged was heavily damaged.

A small tornado touched down about four and a half miles south of Bloomfield. One person was injured as he took cover in a ditch as the tornado approached. Debris from a building fell on him and broke his leg. There was damage to outbuildings and irrigation systems on more than a dozen farms.

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.

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 07:07 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), 12:00Z

10.8 hours before the tornado, 173 km from the path. April 25, 1994.

Skew-T log-pSkew-T log-p diagram, Omaha, NE at 12:00Z on 1994-04-25Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 915 joules per kilogram, CIN -335, lifted condensation level 1004 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, Omaha, NE at 12:00Z on 1994-04-25The 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 268 square meters per square second, 0 to 6 km bulk shear 22 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
915 J/kg
Mixed-layer CIN
-335 J/kg
Surface CAPE
1068 J/kg
Mixed-layer LCL
1004 m above ground
0-6 km bulk shear
22 kt
0-1 km bulk shear
37 kt
0-1 km storm-relative helicity
268 m²/s²
0-3 km storm-relative helicity
302 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
5.1 K/km

Open this sounding in Storm Lab

Omaha, NE (KOAX), 00:00Z

1.2 hours after it, 173 km from the path. April 26, 1994.

Skew-T log-pSkew-T log-p diagram, Omaha, NE at 00:00Z on 1994-04-26Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 1991 joules per kilogram, CIN -5, lifted condensation level 1121 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, Omaha, NE at 00:00Z on 1994-04-26The 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 64 square meters per square second, 0 to 6 km bulk shear 28 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
1991 J/kg
Mixed-layer CIN
-5 J/kg
Surface CAPE
2175 J/kg
Mixed-layer LCL
1121 m above ground
0-6 km bulk shear
28 kt
0-1 km bulk shear
26 kt
0-1 km storm-relative helicity
64 m²/s²
0-3 km storm-relative helicity
77 m²/s²
Significant tornado parameter
0.4
Supercell composite
2.0
0-3 km lapse rate
7.5 K/km

Open this sounding in Storm Lab

The surface observations

Yankton (YKN), 41 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
21:00 UTC83.8456290° 7 kt991.2
22:00 UTC8354150° 3 kt990.5
23:00 UTC8150150° 23 kt48990.5
00:00 UTC6052.88300° 11 kt17992.9

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

This ground now

The live radar over the trackEvery 1994 tornado in NebraskaEvery tornado in Nebraska since 1950Warnings in force in Nebraska nowThe forecast where you are

The other tornadoes of April 25, 1994

27 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
April 2512:50 PM PDTF0Alameda, CA0.730$5,000 to $50,000
April 252:03 PM MDTF0El Paso, CO0.110
April 252:19 PM MDTF0El Paso, CO0.110
April 253:18 PM MDTF0Washington, CO0.110
April 254:35 PM CDTF1Merrick, NE3.023$50,000 to $500,000
April 254:45 PM CDTF0Antelope, NE0.150
April 255:00 PM CDTF0Antelope, NE0.150
April 255:35 PM CDTF0Pierce, NE0.123
April 255:38 PM CDTF0Lincoln, SD0.110$500 to $5,000
April 255:45 PM CDTF0Knox, NE1.523
April 254:56 PM MDTF0Yuma, CO0.120
April 256:10 PM CDTF0Minnehaha, SD0.110$50,000 to $500,000
April 256:10 PM CDTF0Minnehaha, SD0.110
April 256:15 PM CDTF0Minnehaha, SD0.110
April 256:58 PM CDTF1Latimer, OK4.7220$5,000 to $50,000
April 257:01 PM CDTF1Lyon, IA7.040$50,000 to $500,000
April 257:15 PM CDTF0Rock, MN0.110
April 257:35 PM CDTF1LeFlore, OK2.030
April 257:40 PM CDTF0LeFlore, OK0.110
April 257:42 PM CDTF0Tarrant, TX0.110
April 258:00 PM CDTF0Jackson, MN0.110
April 258:50 PM CDTF0Dallas, TX0.110$5,000 to $50,000
April 259:00 PM CDTF2Dallas, TX2.04007$5 million to $50 million
April 259:30 PM CDTF4Dallas, TX6.0800348$50 million to $500 million
April 259:58 PM CDTF0Ellis, TX0.110
April 259:58 PM CDTF0Ellis, TX0.110
April 259:10 PM PDTF0Butte, CA0.120

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.