Tornadoes · United States · Oklahoma · 2003

F2 tornado, Broken Bow, Oklahoma, May 1, 2003

This F2 tornado ran 13.0 miles across McCurtain County on May 1, 2003, touching down at 8:15 PM CDT and reaching 300 yards wide. It killed nobody, and did $260,000 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 mph

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

  3. F2113 to 157 mphthis tornado

    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
F2
Date
May 1, 2003
Touchdown
8:15 PM CDT (01:15 UTC)
Path length
13.0 miles (20.9 km)
Path width
300 yards (274 m)
Deaths
0
Injuries
0
Property damage
$260,000
County
McCurtain County
Touchdown point
34.080, -94.800
Lift-off point
33.950, -94.630
Record number
136

What the Weather Service recorded

A supercell thunderstorm moved southeast across Broken Bow, OK. Two new frame homes under construction had roofs torn off. A total of 30 to 40 wood frame homes had roof and frame damage with windows broken. One home was destroyed. Numerous trees uprooted and snapped. Several power poles blown down.

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

The warnings

17 minutes of warning. NWS SHV issued a tornado warning for this county at 00:58 UTC, 17 minutes before the tornado touched down, in force until 02:00 UTC.

Issued (UTC)ExpiredProductOffice
23:50 UTC00:45 UTCSevere Thunderstorm WarningSHV
00:06 UTC01:00 UTCTornado WarningSHV
00:58 UTC02:00 UTCTornado WarningSHV
02:02 UTC02:30 UTCTornado WarningSHV
02:31 UTC03:30 UTCSevere Thunderstorm WarningSHV
02:53 UTC03:30 UTCTornado WarningSHV
03:34 UTC04:30 UTCSevere Thunderstorm WarningSHV

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, with a 0.05 chance of a tornado within 25 miles. The outlook in force was issued at 00:35 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.

Shreveport, LA (KSHV), 00:00Z

1.3 hours before the tornado, 193 km from the path. May 2, 2003.

Skew-T log-pSkew-T log-p diagram, Shreveport, LA at 00:00Z on 2003-05-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 3075 joules per kilogram, CIN -44, lifted condensation level 926 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, Shreveport, LA at 00:00Z on 2003-05-02The 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 29 square meters per square second, 0 to 6 km bulk shear 27 knots.19395878Sfc1 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
3075 J/kg
Mixed-layer CIN
-44 J/kg
Surface CAPE
4009 J/kg
Mixed-layer LCL
926 m above ground
0-6 km bulk shear
27 kt
0-1 km bulk shear
8 kt
0-1 km storm-relative helicity
29 m²/s²
0-3 km storm-relative helicity
57 m²/s²
Significant tornado parameter
1.0
Supercell composite
5.7
0-3 km lapse rate
6.4 K/km

Open this sounding in Storm Lab

Shreveport, LA (KSHV), 12:00Z

10.7 hours after it, 193 km from the path. May 2, 2003.

Skew-T log-pSkew-T log-p diagram, Shreveport, LA at 12:00Z on 2003-05-02Temperature 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 -72470, lifted condensation level 2290 meters above ground. Wind barbs in knots down the right edge.LCL10008507005003002001001 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, Shreveport, LA at 12:00Z on 2003-05-02The 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 23 square meters per square second, 0 to 6 km bulk shear 22 knots.19395878Sfc1 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
-72470 J/kg
Surface CAPE
13 J/kg
Mixed-layer LCL
2290 m above ground
0-6 km bulk shear
22 kt
0-1 km bulk shear
13 kt
0-1 km storm-relative helicity
23 m²/s²
0-3 km storm-relative helicity
72 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
3.7 K/km

Open this sounding in Storm Lab

The radar

The Western Arkansas radar (KSRX), 145 km away, was scanning. The volume nearest the touchdown began at 01:15 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 OklahomaEvery tornado in Oklahoma since 1950Warnings in force in Oklahoma nowThe forecast where you are

The other tornadoes of May 1, 2003

12 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
May 112:54 PM MDTF0Kimball, NE0.225
May 15:20 PM EDTF0Montgomery, NY0.110$30,000
May 15:55 PM CDTF1Wagoner, OK2.0120$170,000
May 16:01 PM ESTF0Delaware, IN0.110
May 16:04 PM CDTF1Muskogee, OK1.780$300,000
May 16:14 PM CDTF1Pushmataha, OK0.575$3,000
May 16:20 PM ESTF0Randolph, IN0.110
May 16:46 PM CDTF0Sequoyah, OK1.0100
May 16:51 PM CDTF0Sequoyah, OK0.240
May 17:30 PM CDTF0McCurtain, OK2.050
May 17:33 PM CDTF0LeFlore, OK to AR2.575
May 18:24 PM CDTF2Polk, AR11.0200

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.