Tornadoes · United States · Tennessee · 2001

F0 tornado, Dyersburg to Unionville, Tennessee, June 27, 2001

From Dyersburg to Unionville, this F0 tornado ran 0.3 miles across Dyer County on June 27, 2001, touching down at 1:15 PM CDT and reaching 100 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
June 27, 2001
Touchdown
1:15 PM CDT (18:15 UTC)
Path length
0.3 miles (0.5 km)
Path width
100 yards (91 m)
Deaths
0
Injuries
0
County
Dyer County
Touchdown point
35.950, -89.450
Lift-off point
35.950, -89.450
Record number
903

What the Weather Service recorded

The tornado touched down between Finley and Dyersburg and tracked about one-quarter mile before dissipating. Some crop damage was reported.

A second tornado touched down near the town of Unionville. This tornado also was on the ground for about one-quarter of a mile and produced some crop damage.

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

The warnings

6 minutes of warning. NWS MEG issued a tornado warning for this county at 18:09 UTC, 6 minutes before the tornado touched down, in force until 19:00 UTC.

Issued (UTC)ExpiredProductOffice
18:09 UTC19:00 UTCTornado WarningMEG
20:22 UTC21:00 UTCSevere Thunderstorm WarningMEG

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 16:37 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.

Little Rock, AR (KLZK), 12:00Z

6.3 hours before the tornado, 133 km from the path. June 27, 2001.

Skew-T log-pSkew-T log-p diagram, Little Rock, AR at 12:00Z on 2001-06-27Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 1429 joules per kilogram, CIN -37, lifted condensation level 1344 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, Little Rock, AR at 12:00Z on 2001-06-27The 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 25 square meters per square second, 0 to 6 km bulk shear 16 knots.1939Sfc1 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
1429 J/kg
Mixed-layer CIN
-37 J/kg
Surface CAPE
2003 J/kg
Mixed-layer LCL
1344 m above ground
0-6 km bulk shear
16 kt
0-1 km bulk shear
5 kt
0-1 km storm-relative helicity
25 m²/s²
0-3 km storm-relative helicity
70 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
6.5 K/km

Open this sounding in Storm Lab

Little Rock, AR (KLZK), 00:00Z

5.7 hours after it, 133 km from the path. June 28, 2001.

Skew-T log-pSkew-T log-p diagram, Little Rock, AR at 00:00Z on 2001-06-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 767 joules per kilogram, CIN -5, lifted condensation level 523 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 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, Little Rock, AR at 00:00Z on 2001-06-28The 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 -26 square meters per square second, 0 to 6 km bulk shear 20 knots.1939Sfc1 km3 km6 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
767 J/kg
Mixed-layer CIN
-5 J/kg
Surface CAPE
1195 J/kg
Mixed-layer LCL
523 m above ground
0-6 km bulk shear
20 kt
0-1 km bulk shear
15 kt
0-1 km storm-relative helicity
-26 m²/s²
0-3 km storm-relative helicity
77 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1
0-3 km lapse rate
6.2 K/km

Open this sounding in Storm Lab

The surface observations

Dyersburg(Awos) (DYR), 7 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
16:15 UTC80.666.2330° 3 kt1026.1
16:35 UTC80.666.20° 0 kt1026.1
16:55 UTC82.464.4330° 4 kt1025.7
17:15 UTC84.264.40° 0 kt1025.4
17:35 UTC84.264.40° 0 kt1025.4
17:55 UTC84.266.2200° 3 kt1024.7TS
18:15 UTC80.664.4200° 7 kt1024TS
18:35 UTC69.862.6320° 9 kt1024.7TS
18:55 UTC66.260.8320° 8 kt171024.4TS
19:15 UTC66.259320° 8 kt1023.4TS
19:35 UTC66.260.80° 0 kt1024TS
19:55 UTC66.260.860° 14 kt301025.4TS

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

The radar

The Memphis radar (KNQA), 77 km away, was scanning. The volume nearest the touchdown began at 18:14 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 TennesseeEvery tornado in Tennessee since 1950Warnings in force in Tennessee nowThe forecast where you are

The other tornadoes of June 27, 2001

2 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
June 2712:58 PM CDTF0Dyer, TN0.3100
June 277:45 PM PDTF1Pierce, WA2.3400$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.