Strong to severe thunderstorms developed during the late afternoon hours of the 27th along and ahead of a cold front that was moving into eastern Oklahoma. Very unstable air over the area, combined with strong deep-layer wind shear, resulted in widespread severe weather to develop. Several tornadoes, hail up to softball size, and damaging wind gusts occurred with the strongest storms.

Hail in CREEK, OKLAHOMA
From 27-MAY-17 19:13:00 to 27-MAY-17 19:13:00 (CST-6)
Location: MILFAY
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in OTTAWA, OKLAHOMA
From 27-MAY-17 16:46:00 to 27-MAY-17 16:46:00 (CST-6)
Location: MIAMI
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Storm Chaser

Hail in NOWATA, OKLAHOMA
From 27-MAY-17 18:03:00 to 27-MAY-17 18:03:00 (CST-6)
Location: NOWATA
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in ROGERS, OKLAHOMA
From 27-MAY-17 18:39:00 to 27-MAY-17 18:39:00 (CST-6)
Location: CATALE
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Storm Chaser

Hail in OKFUSKEE, OKLAHOMA
From 27-MAY-17 19:44:00 to 27-MAY-17 19:44:00 (CST-6)
Location: WELTY
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Hail in CREEK, OKLAHOMA
From 27-MAY-17 19:49:00 to 27-MAY-17 19:49:00 (CST-6)
Location: SAPULPA
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Hail in ROGERS, OKLAHOMA
From 27-MAY-17 20:30:00 to 27-MAY-17 20:30:00 (CST-6)
Location: CATOOSA
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: NWS Employee

Hail in CREEK, OKLAHOMA
From 27-MAY-17 19:50:00 to 27-MAY-17 19:50:00 (CST-6)
Location: SAPULPA
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Hail in CREEK, OKLAHOMA
From 27-MAY-17 19:50:00 to 27-MAY-17 19:50:00 (CST-6)
Location: SAPULPA
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Hail in TULSA, OKLAHOMA
From 27-MAY-17 19:53:00 to 27-MAY-17 19:53:00 (CST-6)
Location: SAND SPGS
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in MAYES, OKLAHOMA
From 27-MAY-17 20:26:00 to 27-MAY-17 20:26:00 (CST-6)
Location: PRYOR
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in CREEK, OKLAHOMA
From 27-MAY-17 20:48:00 to 27-MAY-17 20:48:00 (CST-6)
Location: MILFAY
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in OKMULGEE, OKLAHOMA
From 27-MAY-17 21:06:00 to 27-MAY-17 21:06:00 (CST-6)
Location: SCHULTER
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Hail in CRAIG, OKLAHOMA
From 27-MAY-17 22:03:00 to 27-MAY-17 22:03:00 (CST-6)
Location: VINITA
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Amateur Radio

Hail in OTTAWA, OKLAHOMA
From 27-MAY-17 22:49:00 to 27-MAY-17 22:49:00 (CST-6)
Location: MIAMI
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in TULSA, OKLAHOMA
From 27-MAY-17 19:57:00 to 27-MAY-17 19:57:00 (CST-6)
Location: PRATTVILLE
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Tornado in SEQUOYAH, OKLAHOMA
From 27-MAY-17 22:45:00 to 27-MAY-17 22:46:00 (CST-6)
Location: SHORT
Tornado F-scale: EF1
Property damage: 0.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

This is the first segment of a two segment tornado. In Sequoyah County, this tornado uprooted trees and snapped large tree limbs as it moved east-northeast, crossing into Crawford County, Arkansas west of Uniontown. Based on this damage, maximum estimated wind in this segment of the tornado was 90 to 100 mph.

Thunderstorm Wind in PUSHMATAHA, OKLAHOMA
From 27-MAY-17 23:25:00 to 27-MAY-17 23:25:00 (CST-6)
Location: CLAYTON
Magnitude: 61.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Thunderstorm wind gusts were estimated to near 70 mph.

Thunderstorm Wind in PUSHMATAHA, OKLAHOMA
From 27-MAY-17 23:31:00 to 27-MAY-17 23:31:00 (CST-6)
Location: CLAYTON
Magnitude: 65.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Strong thunderstorm wind blew down trees.

Thunderstorm Wind in LE FLORE, OKLAHOMA
From 27-MAY-17 23:41:00 to 27-MAY-17 23:41:00 (CST-6)
Location: WHITESBORO
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Thunderstorm wind gusts were estimated to 60 mph.

Thunderstorm Wind in LE FLORE, OKLAHOMA
From 27-MAY-17 23:45:00 to 27-MAY-17 23:45:00 (CST-6)
Location: WHITESBORO
Magnitude: 68.00 MG
Property damage: 2.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Thunderstorm wind gusts were measured to 78 mph. Trees and power lines were blown down.

Thunderstorm Wind in LE FLORE, OKLAHOMA
From 27-MAY-17 23:50:00 to 27-MAY-17 23:50:00 (CST-6)
Location: TALIHINA
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Thunderstorm wind gusts were estimated to 60 mph.

Thunderstorm Wind in LE FLORE, OKLAHOMA
From 28-MAY-17 00:10:00 to 28-MAY-17 00:10:00 (CST-6)
Location: HONTUBBY
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Thunderstorm wind gusts were estimated to 60 mph.

Hail in LE FLORE, OKLAHOMA
From 28-MAY-17 00:13:00 to 28-MAY-17 00:13:00 (CST-6)
Location: BIG CEDAR
Magnitude: 1.75 
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Thunderstorm Wind in LE FLORE, OKLAHOMA
From 28-MAY-17 00:20:00 to 28-MAY-17 00:20:00 (CST-6)
Location: HICKS
Magnitude: 56.00 EG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Strong thunderstorm wind blew the roof off of a barn.

Hail in OTTAWA, OKLAHOMA
From 27-MAY-17 17:30:00 to 27-MAY-17 17:30:00 (CST-6)
Location: FAIRLAND
Magnitude: 2.00 
Property damage: 20.00K
Crop damage: 0.00K
Reported by: Public

Hail in CRAIG, OKLAHOMA
From 27-MAY-17 18:57:00 to 27-MAY-17 18:57:00 (CST-6)
Location: WHITE OAK
Magnitude: 1.25 
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Tornado in OKFUSKEE, OKLAHOMA
From 27-MAY-17 19:20:00 to 27-MAY-17 19:26:00 (CST-6)
Location: MICAWBER
Tornado F-scale: EF0
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Storm Chaser

Storm chasers observed a tornado over open country for about six minutes. An NWS ground survey team was unable to find any damage from the tornado, mainly due to the fact the tornado was over terrain that was inaccessible by roads. Storm chaser photos and video did show some debris occasionally in the tornadic circulation, most likely from trees.

Hail in OTTAWA, OKLAHOMA
From 27-MAY-17 17:20:00 to 27-MAY-17 17:20:00 (CST-6)
Location: WYANDOTTE
Magnitude: 1.75 
Property damage: 20.00K
Crop damage: 0.00K
Reported by: Public

Hail in OSAGE, OKLAHOMA
From 27-MAY-17 17:30:00 to 27-MAY-17 17:30:00 (CST-6)
Location: OKESA
Magnitude: 1.75 
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Park/Forest Service

Hail in OTTAWA, OKLAHOMA
From 27-MAY-17 17:45:00 to 27-MAY-17 17:45:00 (CST-6)
Location: WYANDOTTE
Magnitude: 1.75 
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Hail in WASHINGTON, OKLAHOMA
From 27-MAY-17 17:51:00 to 27-MAY-17 17:51:00 (CST-6)
Location: (BVO)BARTLESVILLE AR
Magnitude: 1.25 
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in NOWATA, OKLAHOMA
From 27-MAY-17 18:16:00 to 27-MAY-17 18:16:00 (CST-6)
Location: NOWATA
Magnitude: 1.75 
Property damage: 20.00K
Crop damage: 0.00K
Reported by: Public

Hail in NOWATA, OKLAHOMA
From 27-MAY-17 18:22:00 to 27-MAY-17 18:22:00 (CST-6)
Location: NOWATA
Magnitude: 1.25 
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in ROGERS, OKLAHOMA
From 27-MAY-17 18:40:00 to 27-MAY-17 18:40:00 (CST-6)
Location: CATALE
Magnitude: 2.00 
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Public

Hail in ROGERS, OKLAHOMA
From 27-MAY-17 18:45:00 to 27-MAY-17 18:45:00 (CST-6)
Location: CATALE
Magnitude: 2.50 
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Hail in CRAIG, OKLAHOMA
From 27-MAY-17 18:47:00 to 27-MAY-17 18:47:00 (CST-6)
Location: WHITE OAK
Magnitude: 1.25 
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Hail in CRAIG, OKLAHOMA
From 27-MAY-17 19:00:00 to 27-MAY-17 19:00:00 (CST-6)
Location: WHITE OAK
Magnitude: 2.00 
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Public

Hail in CRAIG, OKLAHOMA
From 27-MAY-17 19:13:00 to 27-MAY-17 19:13:00 (CST-6)
Location: VINITA ARPT
Magnitude: 1.25 
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Public

Hail in CRAIG, OKLAHOMA
From 27-MAY-17 19:15:00 to 27-MAY-17 19:15:00 (CST-6)
Location: WHITE OAK
Magnitude: 1.25 
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Hail in DELAWARE, OKLAHOMA
From 27-MAY-17 19:30:00 to 27-MAY-17 19:30:00 (CST-6)
Location: GROVE
Magnitude: 1.25 
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Public

Hail in OKFUSKEE, OKLAHOMA
From 27-MAY-17 19:53:00 to 27-MAY-17 19:53:00 (CST-6)
Location: WELTY
Magnitude: 4.25 
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Public

Hail in OKFUSKEE, OKLAHOMA
From 27-MAY-17 19:53:00 to 27-MAY-17 19:53:00 (CST-6)
Location: MASON
Magnitude: 3.00 
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in OKFUSKEE, OKLAHOMA
From 27-MAY-17 19:54:00 to 27-MAY-17 19:54:00 (CST-6)
Location: OKFUSKEE
Magnitude: 2.75 
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Hail in TULSA, OKLAHOMA
From 27-MAY-17 20:15:00 to 27-MAY-17 20:15:00 (CST-6)
Location: WEST TULSA
Magnitude: 1.50 
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Public

Thunderstorm Wind in TULSA, OKLAHOMA
From 27-MAY-17 19:57:00 to 27-MAY-17 19:57:00 (CST-6)
Location: PRATTVILLE
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Thunderstorm wind gusts were estimated to near 60 mph on Highway 97 near W 41st Street in Sand Springs.

Thunderstorm Wind in OKFUSKEE, OKLAHOMA
From 27-MAY-17 20:45:00 to 27-MAY-17 20:45:00 (CST-6)
Location: OKEMAH
Magnitude: 61.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Strong thunderstorm wind blew down trees in Okemah.

Thunderstorm Wind in OKMULGEE, OKLAHOMA
From 27-MAY-17 21:09:00 to 27-MAY-17 21:09:00 (CST-6)
Location: NADDOCK
Magnitude: 52.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

The Oklahoma Mesonet station southeast of Okmulgee measured 60 mph thunderstorm wind gusts.

Thunderstorm Wind in OKMULGEE, OKLAHOMA
From 27-MAY-17 21:25:00 to 27-MAY-17 21:25:00 (CST-6)
Location: MORRIS
Magnitude: 65.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Fire Department/Rescue

Strong thunderstorm wind blew down trees, some of which blocked roads in and around Morris.

Hail in CRAIG, OKLAHOMA
From 27-MAY-17 22:05:00 to 27-MAY-17 22:05:00 (CST-6)
Location: WHITE OAK
Magnitude: 2.75 
Property damage: 15.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Hail in CRAIG, OKLAHOMA
From 27-MAY-17 22:08:00 to 27-MAY-17 22:08:00 (CST-6)
Location: VINITA
Magnitude: 1.75 
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Thunderstorm Wind in MUSKOGEE, OKLAHOMA
From 27-MAY-17 22:15:00 to 27-MAY-17 22:15:00 (CST-6)
Location: WEBBERS FALLS
Magnitude: 56.00 EG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Public

Strong thunderstorm wind damaged the roof of a home.

Hail in OKFUSKEE, OKLAHOMA
From 27-MAY-17 19:39:00 to 27-MAY-17 19:39:00 (CST-6)
Location: WELTY
Magnitude: 2.00 
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Tornado in OKFUSKEE, OKLAHOMA
From 27-MAY-17 19:55:00 to 27-MAY-17 20:02:00 (CST-6)
Location: MASON
Tornado F-scale: EFU
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Storm Chaser

Storm chasers observed a tornado over open country. An NWS storm survey team found no damage associated with the tornado, mainly due to the fact it remained over terrain that was inaccessible by road. An unmanned aircraft system (UAS) piloted by researchers from the Oklahoma State University flew the suspected area where the tornado occurred but data obtained were inconclusive.

Hail in OTTAWA, OKLAHOMA
From 27-MAY-17 16:40:00 to 27-MAY-17 16:40:00 (CST-6)
Location: MIAMI
Magnitude: 1.75 
Property damage: 25.00K
Crop damage: 0.00K
Reported by: COOP Observer

Thunderstorm Wind in SEQUOYAH, OKLAHOMA
From 27-MAY-17 22:30:00 to 27-MAY-17 22:30:00 (CST-6)
Location: SALLISAW
Magnitude: 61.00 EG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Strong thunderstorm wind blew down a tree onto a home.

Hail in CRAIG, OKLAHOMA
From 27-MAY-17 22:33:00 to 27-MAY-17 22:33:00 (CST-6)
Location: BLUEJACKET
Magnitude: 2.50 
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Hail in OTTAWA, OKLAHOMA
From 27-MAY-17 22:55:00 to 27-MAY-17 22:55:00 (CST-6)
Location: MIAMI
Magnitude: 1.50 
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Thunderstorm Wind in LE FLORE, OKLAHOMA
From 27-MAY-17 23:00:00 to 27-MAY-17 23:00:00 (CST-6)
Location: HODGEN
Magnitude: 65.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Strong thunderstorm wind blew down trees.

Hail in OTTAWA, OKLAHOMA
From 27-MAY-17 23:15:00 to 27-MAY-17 23:15:00 (CST-6)
Location: PEORIA
Magnitude: 1.75 
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Public