Severe thunderstorm produced damaging hail, ranging from quarter to softball size across eastern Larimer and northwestern Weld Counties.   The tornado was assigned a damage rating of EF-1.   Areas of sporadic tornado damage were noted from 8 miles south-southwest of Hereford to north of Hereford near the Colorado-Wyoming border. In Weld County, the tornado was approximately 300 yards in width at one point and its path was 7.24 miles in length, it then crossed over into Wyoming.  According County and City Emergency Management, hail damage occurred in the northwest part of Weld county including the towns of Pierce and Nunn.  Several vehicles sustained broken windshields.  The windshields of two patrol vehicles with Weld County Sheriff's Office were damaged.  The officers were responding to unrelated calls when their vehicles were struck by golf ball size hail.  Light damage to cars and general aviation aircraft was also reported at the Northern Colorado Regional Airport in Loveland.

Hail in LARIMER, COLORADO
From 12-JUN-17 13:15:00 to 12-JUN-17 13:15:00 (MST-7)
Location: FT COLLINS/LOVELAND
Magnitude: 1.25 
Reported by: CoCoRaHS

Hail in LARIMER, COLORADO
From 12-JUN-17 13:26:00 to 12-JUN-17 13:26:00 (MST-7)
Location: FT COLLINS/LOVELAND
Magnitude: 1.00 
Reported by: Trained Spotter

Hail in LARIMER, COLORADO
From 12-JUN-17 13:28:00 to 12-JUN-17 13:28:00 (MST-7)
Location: FT COLLINS/LOVELAND
Magnitude: 1.75 
Reported by: CoCoRaHS

Hail in LARIMER, COLORADO
From 12-JUN-17 13:30:00 to 12-JUN-17 13:30:00 (MST-7)
Location: TIMNATH
Magnitude: 1.75 
Reported by: CoCoRaHS

Hail in LARIMER, COLORADO
From 12-JUN-17 13:32:00 to 12-JUN-17 13:32:00 (MST-7)
Location: TIMNATH
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in WELD, COLORADO
From 12-JUN-17 13:32:00 to 12-JUN-17 13:32:00 (MST-7)
Location: WINDSOR
Magnitude: 2.00 
Reported by: Public

Hail in LARIMER, COLORADO
From 12-JUN-17 13:58:00 to 12-JUN-17 13:58:00 (MST-7)
Location: TIMNATH
Magnitude: 1.00 
Reported by: CoCoRaHS

Hail in WELD, COLORADO
From 12-JUN-17 14:18:00 to 12-JUN-17 14:18:00 (MST-7)
Location: NUNN
Magnitude: 1.00 
Reported by: Trained Spotter

Hail in WELD, COLORADO
From 12-JUN-17 14:24:00 to 12-JUN-17 14:24:00 (MST-7)
Location: NUNN
Magnitude: 1.00 
Reported by: Trained Spotter

Hail in WELD, COLORADO
From 12-JUN-17 14:25:00 to 12-JUN-17 14:25:00 (MST-7)
Location: NUNN
Magnitude: 1.00 
Reported by: Amateur Radio

Hail in WELD, COLORADO
From 12-JUN-17 14:38:00 to 12-JUN-17 14:38:00 (MST-7)
Location: PIERCE
Magnitude: 2.50 
Reported by: Broadcast Media

Hail in WELD, COLORADO
From 12-JUN-17 14:43:00 to 12-JUN-17 14:43:00 (MST-7)
Location: NUNN
Magnitude: 1.00 
Reported by: Trained Spotter

Hail in WELD, COLORADO
From 12-JUN-17 14:45:00 to 12-JUN-17 14:45:00 (MST-7)
Location: SEVERANCE
Magnitude: 2.75 
Reported by: Public

Hail in WELD, COLORADO
From 12-JUN-17 14:59:00 to 12-JUN-17 14:59:00 (MST-7)
Location: NUNN
Magnitude: 1.25 
Reported by: Trained Spotter

Hail in WELD, COLORADO
From 12-JUN-17 15:00:00 to 12-JUN-17 15:00:00 (MST-7)
Location: PIERCE
Magnitude: 4.25 
Reported by: Public

Hail in WELD, COLORADO
From 12-JUN-17 15:01:00 to 12-JUN-17 15:01:00 (MST-7)
Location: PURCELL
Magnitude: 1.75 
Reported by: Trained Spotter

Hail in LARIMER, COLORADO
From 12-JUN-17 15:15:00 to 12-JUN-17 15:15:00 (MST-7)
Location: TIMNATH
Magnitude: 1.50 
Reported by: CoCoRaHS

Hail in WELD, COLORADO
From 12-JUN-17 15:35:00 to 12-JUN-17 15:35:00 (MST-7)
Location: HEREFORD
Magnitude: 3.00 
Reported by: Trained Spotter

Hail in WELD, COLORADO
From 12-JUN-17 15:40:00 to 12-JUN-17 15:40:00 (MST-7)
Location: HEREFORD
Magnitude: 1.75 
Reported by: Trained Spotter

Hail in WELD, COLORADO
From 12-JUN-17 15:40:00 to 12-JUN-17 15:40:00 (MST-7)
Location: HEREFORD
Magnitude: 1.50 
Reported by: Trained Spotter

Hail in WELD, COLORADO
From 12-JUN-17 15:47:00 to 12-JUN-17 15:47:00 (MST-7)
Location: HEREFORD
Magnitude: 1.75 
Reported by: Storm Chaser

Hail in WELD, COLORADO
From 12-JUN-17 15:48:00 to 12-JUN-17 15:48:00 (MST-7)
Location: HEREFORD
Magnitude: 2.75 
Reported by: Trained Spotter

Tornado in WELD, COLORADO
From 12-JUN-17 15:40:00 to 12-JUN-17 15:57:00 (MST-7)
Location: HEREFORD
Tornado F-scale: EF1
Reported by: NWS Storm Survey

A tornado touched down southwest of Hereford and continued to quickly move north northeast into Wyoming.  Areas of sporadic tornado damage were noted from 8 miles south southwest of Hereford to north of Hereford near the Colorado-Wyoming border.  The damage along the patch ranged from EF-0 to EF-1.