Thunderstorms initiated along a dry line in central Colorado moving east and forming a cluster of supercells that produced up to 70 mph wind gusts and large hail up to tennis ball in size across Yuma County. Supercells developed over Cheyenne County as the northern cluster crossed into Kansas and Nebraska. The southern cells eventually formed a cluster that was able to produce up to half dollar sized hail, a landspout, and caused a portion of Highway 385 to become impassable due to flash flooding.

Hail in YUMA, COLORADO
From 12-JUL-20 15:51:00 to 12-JUL-20 15:51:00 (MST-7)
Location: LAIRD
Magnitude: 1.75 
Reported by: Public

Hail in YUMA, COLORADO
From 12-JUL-20 15:42:00 to 12-JUL-20 15:42:00 (MST-7)
Location: WRAY
Magnitude: 1.25 
Reported by: Public

Hail in CHEYENNE, COLORADO
From 12-JUL-20 17:15:00 to 12-JUL-20 17:35:00 (MST-7)
Location: CHEYENNE WELLS
Magnitude: 1.25 
Reported by: Trained Spotter

Trained spotter and Cheyenne Wells law enforcement observed hail up to half dollar in size over a duration of twenty minutes in the town of Cheyenne Wells.

Flash Flood in CHEYENNE, COLORADO
From 12-JUL-20 16:45:00 to 12-JUL-20 19:30:00 (MST-7)
Location: CHEYENNE WELLS
Flood cause: Heavy Rain
Property damage: 2.50K
Crop damage: 0.01K
Reported by: Law Enforcement

Local law enforcement and a trained storm spotter provided several reports of several inches of water flowing across Hwy 385 at mile marker 147 south of Cheyenne Wells.

Thunderstorm Wind in YUMA, COLORADO
From 12-JUL-20 15:06:00 to 12-JUL-20 15:06:00 (MST-7)
Location: ABARR
Magnitude: 61.00 EG
Property damage: 1.00K
Reported by: Trained Spotter

Trained spotter reported a large, dead tree blown over along with numerous tree limbs down on the property due to strong winds associated with a thunderstorm.

Tornado in CHEYENNE, COLORADO
From 12-JUL-20 16:50:00 to 12-JUL-20 17:00:00 (MST-7)
Location: CHEYENNE WELLS
Tornado F-scale: EFU
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Received a couple different reports of landspouts around this time. However, based on radar imagery and pictures/videos received, it appears that one single longer-lasting landspout tornado occurred. Reports described the times accurately and indicated the tornado occurred for around 10 minutes in duration, remaining nearly stationary.

Hail in YUMA, COLORADO
From 12-JUL-20 15:08:00 to 12-JUL-20 15:08:00 (MST-7)
Location: ABARR
Magnitude: 0.88 
Reported by: Trained Spotter

Trained spotter observed pea to nickel sized hail.

Hail in YUMA, COLORADO
From 12-JUL-20 15:34:00 to 12-JUL-20 15:34:00 (MST-7)
Location: VERNON
Magnitude: 1.00 
Reported by: COOP Observer

Hail in YUMA, COLORADO
From 12-JUL-20 15:54:00 to 12-JUL-20 15:54:00 (MST-7)
Location: LAIRD
Magnitude: 2.50 
Reported by: Public

Public citizen observed hail up to tennis ball in size. Most of the hail was nickel to quarter in size. As hail fell at the location, winds were estimated to have 40 mph gusts.

Hail in YUMA, COLORADO
From 12-JUL-20 15:14:00 to 12-JUL-20 15:14:00 (MST-7)
Location: VERNON
Magnitude: 0.88 
Reported by: Public

Public citizen observed nickel sized hail with winds gusting up to 40 mph.

Hail in YUMA, COLORADO
From 12-JUL-20 15:35:00 to 12-JUL-20 15:35:00 (MST-7)
Location: WRAY BOWMAN ARPT
Magnitude: 1.25 
Reported by: Trained Spotter

Hail in YUMA, COLORADO
From 12-JUL-20 15:42:00 to 12-JUL-20 15:42:00 (MST-7)
Location: WRAY
Magnitude: 2.50 
Reported by: Public

Hail in YUMA, COLORADO
From 12-JUL-20 15:43:00 to 12-JUL-20 15:43:00 (MST-7)
Location: VERNON
Magnitude: 1.00 
Reported by: CoCoRaHS

Hail in YUMA, COLORADO
From 12-JUL-20 15:28:00 to 12-JUL-20 15:28:00 (MST-7)
Location: VERNON
Magnitude: 1.75 
Reported by: Public

A public citizen reported hail slightly larger than golf ball sized that was on the ground for approximately 10 minutes before being estimated for size.