An upper level low passing over Wyoming combined with a strong jet stream to bring an outbreak of severe thunderstorms. Four tornadoes were reported on this day, the most in one day since June 12, 2017. There was one each in Johnson and Sweetwater County and two in Natrona County. The largest tornado was south of Midwest in northern Natrona County where a horse trailer was flipped and fuel tanks were blown away. Very large hail also occurred with some of the storms. The largest hail occurred in southern Johnson County and northern Natrona County where baseball size hail was reported. Another severe thunderstorms moved from Lander to Riverton and dropped quarter to golf ball size hail, causing damage to many vehicles.

Tornado in JOHNSON, WYOMING
From 23-JUN-23 13:40:00 to 23-JUN-23 13:41:00 (MST-7)
Location: KAYCEE
Tornado F-scale: EF0
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

A rancher reported a brief touchdown of a tornado north of Kaycee to the Johnson County Sheriffs office.

Hail in NATRONA, WYOMING
From 23-JUN-23 14:15:00 to 23-JUN-23 14:40:00 (MST-7)
Location: MERINO
Magnitude: 2.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

A supercell thunderstorm moved across northern Natrona County and brought very large hail to the south of Midwest. Hail almost baseball size fell in a farm to south of Midwest as well as along Interstate 25.

Hail in FREMONT, WYOMING
From 23-JUN-23 11:00:00 to 23-JUN-23 11:20:00 (MST-7)
Location: ST STEPHENS
Magnitude: 1.75 
Property damage: 3.00M
Crop damage: 0.00K
Reported by: NWS Employee

There were numerous reports of quarter to golf ball size hail in around around Riverton, with the largest hail stones reported on the east side of Riverton. Many vehicles sustained windshield and body damage from the hail. Dozens of homes on the east side of Riverton had roof shingle damage, with roof replacements occurring regularly over the next 4 months.

Tornado in NATRONA, WYOMING
From 23-JUN-23 13:15:00 to 23-JUN-23 13:35:00 (MST-7)
Location: MIDWEST
Tornado F-scale: EF1
Property damage: 100.00K
Crop damage: 0.00K
Reported by: Emergency Manager

There were numerous reports, pictures, and video of a cone tornado that touched down to the south of Midwest, WY. The tornado remained over open country for the most part. However, the tornado damaged one home where a large section of the roof was removed. Exterior walls remained standing. A trailer was overturned, fuel tanks were blown away, and trees near the residence were damaged.
Based on the FR12 damage indicator category, this tornado was rated EF1 using a low to middle end DOD estimate for the type of construction. Winds are estimated to have been around 110 mph. Stronger winds could have occurred elsewhere along the track, but open country prevented any further evidence of wind damage. Damage survey completed by county emergency management officials.

Hail in FREMONT, WYOMING
From 23-JUN-23 10:15:00 to 23-JUN-23 10:30:00 (MST-7)
Location: (LND)HUNT FLD LANDER
Magnitude: 1.25 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter reported half dollar size hail north of Lander. Video from a local media outlet showed quarter size hail falling in Lander.

Hail in FREMONT, WYOMING
From 23-JUN-23 11:40:00 to 23-JUN-23 11:50:00 (MST-7)
Location: LYSITE
Magnitude: 2.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

The public reported hail larger than golf balls to the north of Lysite.

Tornado in SWEETWATER, WYOMING
From 23-JUN-23 12:35:00 to 23-JUN-23 12:37:00 (MST-7)
Location: GRANGER
Tornado F-scale: EFU
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Video from the public showed a narrow rope-shaped tornado northeast of Granger. The tornado touched down over open country, and caused no known damage. A rating of EFU was assigned because the brief tornado traversed land lacking damage indicators such as trees structures.

Tornado in NATRONA, WYOMING
From 23-JUN-23 13:37:00 to 23-JUN-23 13:40:00 (MST-7)
Location: MERINO
Tornado F-scale: EFU
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Social Media

The public sent a picture of a rope tornado to the north of Natrona. The tornado remained over open country and caused no known damage. A rating of EFU was assigned because the tornado traversed remote land lacking damage indicators such as trees structures.

Hail in JOHNSON, WYOMING
From 23-JUN-23 13:15:00 to 23-JUN-23 13:45:00 (MST-7)
Location: BARNUM
Magnitude: 2.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: NWS Employee

A supercell thunderstorm developed in the lee of the Bighorn range and brought large hail from Barnum to Kaycee. Hail the size of baseballs fell near Barnum with quarter size hail reported in Kaycee.