Tornadoes · United States · Nebraska · 2003

F0 tornado, Greeley to Spalding, Nebraska, April 18, 2003

From Greeley to Spalding, this F0 tornado ran 3.5 miles across Greeley County on April 18, 2003, touching down at 6:40 PM CDT and reaching 50 yards wide. It killed nobody, and did $40,000 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 mphthis tornado

    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 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
F0
Date
April 18, 2003
Touchdown
6:40 PM CDT (23:40 UTC)
Path length
3.5 miles (5.6 km)
Path width
50 yards (46 m)
Deaths
0
Injuries
0
Property damage
$40,000
County
Greeley County
Touchdown point
41.680, -98.480
Lift-off point
41.730, -98.430
Record number
792

What the Weather Service recorded

The severe thunderstorm which had spawned some brief tornados earlier was to blame for a short path tornado centered about 6 miles north of Greeley. The tornado upset 2 center irrigation pivots and damaged a shelter belt.

Another tornado set down west of Spalding and overturned a brand new center irrigation pivot in its path.

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

The warnings

44 minutes of warning. NWS GID issued a tornado warning for this county at 22:56 UTC, 44 minutes before the tornado touched down, in force until 23:45 UTC.

Issued (UTC)ExpiredProductOffice
22:56 UTC23:45 UTCTornado WarningGID

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 19:50 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

11.7 hours before the tornado, 179 km from the path. April 18, 2003.

Skew-T log-pSkew-T log-p diagram, Omaha, NE at 12:00Z on 2003-04-18Temperature 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 -80620, lifted condensation level 637 meters above ground. Wind barbs in knots down the right edge.LCL10008507005003002001001 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 12:00Z on 2003-04-18The 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 46 square meters per square second, 0 to 6 km bulk shear 47 knots.1939587897Sfc1 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
-80620 J/kg
Surface CAPE
0 J/kg
Mixed-layer LCL
637 m above ground
0-6 km bulk shear
47 kt
0-1 km bulk shear
11 kt
0-1 km storm-relative helicity
46 m²/s²
0-3 km storm-relative helicity
120 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
3.3 K/km

Open this sounding in Storm Lab

Omaha, NE (KOAX), 00:00Z

0.3 hours after it, 179 km from the path. April 19, 2003.

Skew-T log-pSkew-T log-p diagram, Omaha, NE at 00:00Z on 2003-04-19Temperature 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 0, lifted condensation level 588 meters above ground. Wind barbs in knots down the right edge.LCLEL10008507005003002001001 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 2003-04-19The 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 208 square meters per square second, 0 to 6 km bulk shear 68 knots.1939587897Sfc1 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
0 J/kg
Surface CAPE
0 J/kg
Mixed-layer LCL
588 m above ground
0-6 km bulk shear
68 kt
0-1 km bulk shear
38 kt
0-1 km storm-relative helicity
208 m²/s²
0-3 km storm-relative helicity
254 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.3
0-3 km lapse rate
5.3 K/km

Open this sounding in Storm Lab

The surface observations

Ord/Sharp Field (ODX), 42 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
21:53 UTC5351130° 8 kt998BR
22:00 UTC53.651.8130° 7 kt998-RA BR
22:21 UTC53.651.8110° 8 kt997.6-RA BR
22:36 UTC51.851.8100° 8 kt997.3RA BR
22:40 UTC51.851.880° 9 kt997VCTS RA BR
22:53 UTC525270° 10 kt997TSRA BR
22:59 UTC53.651.860° 10 kt997-TSRA BR
23:04 UTC53.651.850° 7 kt997.3+TSRA BR
23:08 UTC53.651.8 5 kt998.3+TSRA BR
23:10 UTC53.651.8130° 8 kt997.6+TSRA FG
23:14 UTC53.651.8320° 12 kt15997.6+TSRA FG
23:19 UTC51.851.8330° 5 kt15997.6TSRA BR
23:23 UTC51.851.8 4 kt997.3VCTS RA BR
23:25 UTC51.850270° 4 kt997.3RA BR
23:53 UTC5350290° 4 kt997.6
00:53 UTC5251260° 8 kt999.7BR

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

The radar

The Grand Island radar (KUEX), 154 km away, was scanning. The volume nearest the touchdown began at 23:39 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.

This ground now

The live radar over the trackEvery 2003 tornado in NebraskaEvery tornado in Nebraska since 1950Warnings in force in Nebraska nowThe forecast where you are

The other tornadoes of April 18, 2003

8 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
April 185:00 PM EDTF1Palm Beach, FL3.030
April 184:20 PM CDTF0Dawson, NE0.125
April 184:47 PM CDTF0Custer, NE2.020$20,000
April 184:56 PM CDTF0Custer, NE0.520$20,000
April 185:25 PM CDTF0Sherman, NE0.125
April 185:40 PM CDTF0Sherman, NE0.125
April 185:55 PM CDTF0Valley, NE0.125
April 186:24 PM CDTF0Greeley, NE2.050$70,000

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.