F1 tornado, Purcell, Oklahoma, April 5, 1999

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.

Rating

F1

Date

April 5, 1999

Touchdown

6:03 AM CDT (11:03 UTC)

Path length

3.0 miles (4.8 km)

Path width

0 yards (0 m)

Deaths

0

Injuries

0

Property damage

$40,000

County

McClain County

Touchdown point

34.920, -97.480

Lift-off point

35.020, -97.500

Record number

906

A long line of thunderstorms moved east across most of western and central Oklahoma during the early morning of the 5th resulting in widespread straight-line damage and 5 tornadoes. Severe thunderstorms first developed in Magnum in Greer County where large tree limbs were blown down. In Woods County trees were downed 12 miles west of Alva near the intersection of Highway 64 and Highway 14. In addition, power poles were snapped; house roofs and barns were damaged, and sheds were blown over. Power lines were also downed 7 miles west of Alva. In Washita County many house roofs were damaged in Dill City, and power lines were downed 5 miles southwest of Dill City. In Woodward County large tree limbs were downed in Belva, while in Mooreland a camper trailer was destroyed; fences and tree limbs were blown down, and numerous vehicles were damaged. A survey conducted by the National Weather Service concluded that an F1 tornado touched down 6 miles west-southwest of Cherokee in Alfalfa County and tracked northeast for 7 miles before dissipating about 4 miles north of Cherokee. Two hay storage barns and another storage barn at a feedlot were destroyed, and a large irrigation system was destroyed. Also in Alfalfa County a haybarn was destroyed in Ingersoll; the roof was ripped off of a boat house, and another house received minor roof damage. Large power poles were blown down 5 miles northeast of Cherokee, and a barn was blown down in Amorita, also in Alfalfa County. Another tornado was confirmed by a National Weather Service survey 4 miles north-northeast of Ames in Major County. This tornado, rated an F0, touched down in an open field with no known damage. The same thunderstorm that produced this tornado was also responsible for straight-line winds which blew a moving vehicle off the road 4 miles north of Ames. A tornado also developed 2 miles north of Carrier in Garfield County, but no damage (F0) was observed as it touched down briefly in an open field. Another tornado, 3rd of the day, touched down about 8 miles south-southwest of Wakita in Garfield County and tracked northeast to about 5 miles south of Wakita. One sheet metal/wood frame hay storage barn was destroyed, and another was damaged. A truck was damaged, and tree limbs were blown down. The weak nature of the structures damaged or destroyed by this tornado warranted an F0 intensity rating. In addition to the tornado damage in Garfield County, straight-line wind damage was observed 2 miles north of Carrier where road signs were blown over, 7 miles south of Wakita where a shed was destroyed; a barn was blown over; a truck was damaged, and a few homes suffered roof and window damage, and 12 miles northwest of Medford where a semi was blown over, while in Grant County straight-line winds blew down power lines 6 miles west of Wakita.As the line of thunderstorms continued to move east across portions of central Oklahoma, another tornado, an F1, developed in McClain County about 1 mile south of the intersection of Highway 59 and Highway 39, and moved northeast for 3 miles before dissipating. The most significant damage occurred near the intersection of Highway 39 and Youth Camp Road where the roof of a medium-sized house was severely damaged; 2 barns were destroyed, and a travel trailer was blown over onto a nearby car. In Pottowatomie County 1 mile southwest of McLoud a gazebo was destroyed, and a metal barn was damaged. Large tree limbs and a chainlink fence were also blown down, while in Wynnewood in Garvin County a barn was destroyed, and the roof of a horse barn was blown off; numerous trees and power poles were downed, and many homes received minor roof and structural damage. Severe thunderstorm winds also damaged a hangar and aircraft at the Ardmore Regional Airport in Ardmore in Carter County, while widespread damage occurred in Holdenville in Hughes County. Three homes received major damage, while 143 other homes received minor damage. Trees, power lines, and a radio tower were blown down, and at least one vehicle was damaged.

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

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 Storm Prediction Center had this point in a General Thunderstorms Risk. The outlook in force was issued at 06:06 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 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.

The Norman radar (KTLX), 45 km away, was scanning. The volume nearest the touchdown began at 11:03 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.

The live radar over the trackEvery 1999 tornado in OklahomaEvery tornado in Oklahoma since 1950Warnings in force in Oklahoma nowThe forecast where you are

25 more were confirmed in the United States that day.

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.

NOAA Storm Prediction Center tornado database, 1950-2025, the official record kept by NOAA's Storm Prediction Center.