EF3 tornado, Connerville to Pontotoc, Oklahoma, May 9, 2016

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 mph

   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 mphthis tornado

   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

EF3

Date

May 9, 2016

Touchdown

5:18 PM CDT (22:18 UTC)

Lifted

5:34 PM CDT (22:34 UTC)

On the ground

16 minutes

Path length

9.1 miles (14.6 km)

Path width

700 yards (640 m)

Deaths

1

Injuries

0

Property damage

$250,000

Counties

Johnston and Coal counties

Touchdown point

34.391, -96.638

Lift-off point

34.420, -96.484

Record number

1605091618-03

38 damage points were recorded along this path by NWS OUN, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF2. The highest wind the damage implies is 170 mph.

• downed tree, start of path?
• broken limbs from dead trees
• trees down, tbars bent, telephone poles down, tornado center
• small area of limbs down, no other noticable damage to nearby buildings, probable start point of intermittent, multi-vortext weak tornado

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

With the help of an upper low, storms fired along the dryline in central Oklahoma on the 9th, with some of them becoming severe.

The tornado formed near US-377/OK-99 in northern Johnston County about 4 miles south of Connerville. The tornado damage trees and power poles, and caused roof damage to a home as it crossed Tower Road. Passing Deadman Spring Road, the tornado destroyed a modular home where the fatality occurred. A truck parked at this house was carried 250 yards to the east. The tornado continued moving east-northeast with more tree damage, and light damage to a couple of houses at the edge of the tornado path. Fortunately as the tornado had weakened as it approached the town of Bromide with only light tree damage observed there. ||From about 1.25 miles west of Bromide to where it dissipated just east of Bromide, the tornado moved down the Johnston-Coal county line affecting both counties. The center line of the tornado moved into Coal County in Bromide.

A mini-supercell that developed between the Katie-Sulphur storm and the Bromide-Atoka storm produced a tornado in northern Johnston County that was observed by spotters and chasers, including an NWS employee, and broadcast live on Oklahoma City television by a media helicopter. The tornado occurred in open grassland on a ranch and produced no damage. The specific path could be determined by the proximity to landmarks observed on the helicopter footage.

The deaths

1 direct deaths are recorded for this tornado, each with what Storm Data knows of it.

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. One was issued for the county at another hour that day.

The county was under a tornado watch, issued at 19:36 UTC and running to 23:32 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 Enhanced Risk, with a 0.10 chance of a tornado within 25 miles. The outlook in force was issued at 20:00 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.

Atoka Municipal Airport (AQR), 38 km from the path, in the two hours either side.

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

The Norman radar (KTLX), 122 km away, was scanning. The volume nearest the touchdown began at 22:16 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.

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 2016 tornado in OklahomaEvery tornado in Oklahoma since 1950Warnings in force in Oklahoma nowThe forecast where you are

27 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.