EF1 tornado, Tulsa to Collinsville, Oklahoma, May 21, 2019

1. EF065 to 85 mph

   Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.

2. EF186 to 110 mphthis tornado

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

3. EF2111 to 135 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. EF3136 to 165 mph

   Severe damage. Whole stories of well-built houses destroyed, large buildings badly damaged, trains overturned, trees debarked, heavy cars lifted and thrown.

5. EF4166 to 200 mph

   Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.

6. EF5over 200 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

EF1

Date

May 21, 2019

Touchdown

6:31 AM CDT (11:31 UTC)

Lifted

6:35 AM CDT (11:35 UTC)

On the ground

4 minutes

Path length

2.3 miles (3.7 km)

Path width

550 yards (503 m)

Deaths

0

Injuries

1

Property damage

$125,000

County

Tulsa County

Touchdown point

36.174, -95.972

Lift-off point

36.179, -95.932

Record number

1905210531-01

40 damage points were recorded along this path by NWS TSA, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF1. The highest wind the damage implies is 98 mph.

• damaged pole being replaced

Survey points are preliminary and are the raw material the published rating was built from. Source: NWS Damage Assessment Toolkit.

A strong upper level storm system moved into the Southern Plains from the Rockies on the 20th and 21st. The attendant warm front moved from northern Texas northward into northeastern Oklahoma during the day on the 20th, and then the cold front associated with this storm system moved through eastern Oklahoma during the late evening of the 20th and early morning hours of the 21st. Warm, moist, and very unstable air resided across eastern Oklahoma ahead of this system. This pattern resulted in multiple rounds of severe thunderstorms across eastern Oklahoma from the early afternoon of the 20th through late morning of the 21st. Very strong wind shear coexisting with the strong instability resulted in some supercell thunderstorms that produced large hail up to golfball size and multiple tornadoes on the 20th. A squall line developed along the cold front that moved into the area during the morning of the 21st, and that line of storms produced multiple tornadoes along the leading edge. Locally heavy rainfall and subsequent flash flooding occurred across northeastern Oklahoma as multiple rounds of thunderstorms affected generally the same area.

This tornado moved north across a mainly industrial area east of N Peoria Avenue and south of Highway 75. Radar detected a tornadic debris signature in this area, and a survey team from NWS Tulsa investigated the area. No damage was found in the industrial area, as access to the area where the tornado occurred was limited. This tornado dissipated just before a stronger tornado developed near this location.

This tornado developed just south of E Pine Street at N Rockford Avenue and moved east. The tornado damaged a number of homes and structures, blew down trees, and snapped two power poles. A man was injured when a large tree fell onto his house. The tornado dissipated just north of E Pine Street near N Oswego Avenue. Based on this damage, maximum estimated wind in the tornado was 90 to 100 mph.

This tornado damaged trees, and resulted in a radar detected tornadic debris signature. It was observed by several people.

This tornado snapped large tree limbs north of the TTC Owasso Campus. Based on this damage, maximum estimated wind in the tornado was 65 to 70 mph.

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

14 minutes of warning. NWS TSA issued a tornado warning for this county at 11:17 UTC, 14 minutes before the tornado touched down, in force until 12:00 UTC.

The county was under a tornado watch, issued at 10:10 UTC and running to 13:54 UTC.

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 Slight Risk, with a 0.02 chance of a tornado within 25 miles. The outlook in force was issued at 05:40 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.

Tulsa International Airport(Aw) (TUL), 6 km from the path, in the two hours either side.

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

The Tulsa radar (KINX), 35 km away, was scanning. The volume nearest the touchdown began at 11:30 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.

Local storm reports within 60 km of the path, in the three hours either side.

From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.

The live radar over the trackEvery 2019 tornado in OklahomaEvery tornado in Oklahoma since 1950Warnings in force in Oklahoma nowThe forecast where you are

30 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.