Tornadoes · United States · Missouri · 2001

F0 tornado, Amazonia to Fillmore, Missouri, May 4, 2001

From Amazonia to Fillmore, this F0 tornado ran 20.0 miles across Andrew County on May 4, 2001, touching down at 6:16 PM CDT and reaching 30 yards wide. It killed nobody.

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
May 4, 2001
Touchdown
6:16 PM CDT (23:16 UTC)
Path length
20.0 miles (32.2 km)
Path width
30 yards (27 m)
Deaths
0
Injuries
0
County
Andrew County
Touchdown point
39.920, -94.930
Lift-off point
39.920, -94.930
Record number
740

What the Weather Service recorded

Brief tornado touchdown observed by a trained spotter.

Two small tornados were observed by trained spotters and the general public, 5 miles northwest of Fillmore, moving north. No damage or injuries were reported.

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

The warnings

2 minutes of warning. NWS EAX issued a tornado warning for this county at 23:14 UTC, 2 minutes before the tornado touched down, in force until 00:15 UTC.

Issued (UTC)ExpiredProductOffice
23:14 UTC00:15 UTCTornado WarningEAX

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 20:05 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.

Topeka, KS (KTOP), 12:00Z

11.3 hours before the tornado, 119 km from the path. May 4, 2001.

Skew-T log-pSkew-T log-p diagram, Topeka, KS at 12:00Z on 2001-05-04Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 147 joules per kilogram, CIN -71, lifted condensation level 792 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, Topeka, KS at 12:00Z on 2001-05-04The 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 126 square meters per square second, 0 to 6 km bulk shear 19 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
147 J/kg
Mixed-layer CIN
-71 J/kg
Surface CAPE
43 J/kg
Mixed-layer LCL
792 m above ground
0-6 km bulk shear
19 kt
0-1 km bulk shear
25 kt
0-1 km storm-relative helicity
126 m²/s²
0-3 km storm-relative helicity
135 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.8
0-3 km lapse rate
5.2 K/km

Open this sounding in Storm Lab

Topeka, KS (KTOP), 00:00Z

0.7 hours after it, 119 km from the path. May 5, 2001.

Skew-T log-pSkew-T log-p diagram, Topeka, KS at 00:00Z on 2001-05-05Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 157 joules per kilogram, CIN -7, lifted condensation level 1636 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, Topeka, KS at 00:00Z on 2001-05-05The 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 85 square meters per square second, 0 to 6 km bulk shear 33 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
157 J/kg
Mixed-layer CIN
-7 J/kg
Surface CAPE
518 J/kg
Mixed-layer LCL
1636 m above ground
0-6 km bulk shear
33 kt
0-1 km bulk shear
18 kt
0-1 km storm-relative helicity
85 m²/s²
0-3 km storm-relative helicity
149 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.7
0-3 km lapse rate
7.5 K/km

Open this sounding in Storm Lab

The surface observations

St. Joseph (STJ), 17 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
21:17 UTC69.864.4320° 5 kt1015.6
21:39 UTC71.66850° 7 kt1015.6RA BR
21:53 UTC726850° 9 kt1015.6-RA BR
22:30 UTC71.666.270° 9 kt1015.2+RA BR
22:36 UTC69.866.240° 12 kt1014.9+RA BR
22:42 UTC71.666.270° 10 kt1014.6-RA BR
22:53 UTC7168210° 7 kt1014.9VCTS
23:15 UTC71.666.2100° 9 kt1014.9
23:28 UTC71.666.2100° 11 kt1014.9VCTS
23:43 UTC71.666.2100° 10 kt1014.9
23:53 UTC726790° 9 kt1014.9
00:53 UTC7062100° 8 kt1015.2

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

The radar

The Pleasant Hill radar (KEAX), 136 km away, was scanning. The volume nearest the touchdown began at 23:16 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 2001 tornado in MissouriEvery tornado in Missouri since 1950Warnings in force in Missouri nowThe forecast where you are

The other tornadoes of May 4, 2001

12 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
May 44:05 PM CDTF1Tillman, OK0.52001$250,000
May 45:45 PM CDTF0Richardson, NE0.140
May 46:15 PM CDTF0Johnson, NE0.140
May 46:48 PM CDTF0Nemaha, NE0.140
May 46:48 PM CDTF0Andrew, MO25.00
May 47:05 PM CDTF0Grady, OK0.225
May 47:20 PM CDTF0Grady, OK0.750
May 47:25 PM CDTF0Nodaway, MO25.00
May 47:43 PM CDTF0Johnson, NE0.140
May 48:42 PM CDTF1Johnson, TX0.350$30,000
May 49:43 PM CDTF1Tarrant, TX8.01502$5.0 million
May 49:45 PM CDTF1Johnson, TX2.8501$100,000

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.