A supercell produced extensive severe weather over Valley and Sherman counties this Wednesday evening. Around 2 p.m. CDT, a lone thunderstorm formed near the South Dakota-Nebraska border and eventually became supercellular. As it moved southeastward toward central Nebraska, other isolated supercells joined. Storm evolution was complex this afternoon, with multiple storm splits and cell mergers. At 4 p.m. CDT, one of the new cells formed in close proximity to the initial storm, along the Holt-Rock county border. This storm took over, increased in size and became the dominant storm. Given its proximity to the initial storm, it is likely that some constructive interference occurred between the two. While all other storms tracked southeast or south-southeastward, this storm tracked nearly due south, entering northern Valley County by 6 p.m. CDT. This storm had a history of producing severe wind and hail, so it is likely that continued as the storm tracked across Valley county. However, due to the sparse population, no severe reports were received until the storm hit the town of Ord. Hail as large as golf balls fell in town and the airport ASOS measured winds of 60 mph. Isolated, but intense, wind damage occurred between Ord and the Valley-Sherman county border. A NWS storm survey estimated winds between 70 and 100 mph. The roof of a home approximately 4 miles east-southeast of Ord was damaged. Roughly 120 square feet of roofing material was removed and blown into the yard, including 60 square feet of roof sheathing. The portion removed was at a gable end where the wind lifted up the outlookers/soffit, taking some of the roof with it. Damage also occurred to crops, a barn, a large storage shed and a center pivot irrigation system. Multiple grain bins were also blown over and/or destroyed. The storm continued south, hugging the Sherman-Howard county line, and still producing hail as large as 1.5 inches in diameter. It then rapidly dissipated over northwestern Hall County.
The synoptic setup was very innocuous, with weak forcing. The surface was dominated by high pressure that extended from the Central Plains into the Great Lakes. The storms initiated along a weak surface trough which was situated in the warm sector a low pressure system near Lake Winnipeg. Temperatures were in the low 80s, with dewpoints in the low 60s. Despite unimpressive mid-level lapse rates, MLCAPE was around 2000 J/kg. Deep layer shear was near 50 knots, and storm-relative helicity was between 100 and 200 m2/s2. Both of these shear values were supportive of supercell storm mode. The upper-level flow was west-northwest, with a ridge over the western U.S. and a trough over the east.

Hail in SHERMAN, NEBRASKA
From 24-JUL-13 18:00:00 to 24-JUL-13 18:00:00 (CST-6)
Location: ASHTON
Magnitude: 1.50 
Property damage: 100.00K
Crop damage: 5.00M
Reported by: Public

Hail in HOWARD, NEBRASKA
From 24-JUL-13 18:28:00 to 24-JUL-13 18:28:00 (CST-6)
Location: BOELUS
Magnitude: 1.50 
Property damage: 150.00K
Crop damage: 5.00M
Reported by: Public

Thunderstorm Wind in VALLEY, NEBRASKA
From 24-JUL-13 17:15:00 to 24-JUL-13 17:15:00 (CST-6)
Location: ORD
Magnitude: 52.00 EG
Property damage: 100.00K
Crop damage: 1.00M
Reported by: Public

Wind gusts estimated at 60 MPH were accompanied by quarter sized hail.

Thunderstorm Wind in VALLEY, NEBRASKA
From 24-JUL-13 17:30:00 to 24-JUL-13 17:30:00 (CST-6)
Location: NORTH LOUP
Magnitude: 52.00 EG
Property damage: 25.00K
Crop damage: 2.00M
Reported by: Public

Wind gusts estimated at 60 MPH were accompanied by walnut size hail.  Some minor tree damage was reported.

Hail in VALLEY, NEBRASKA
From 24-JUL-13 17:15:00 to 24-JUL-13 17:15:00 (CST-6)
Location: ORD
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Hail in VALLEY, NEBRASKA
From 24-JUL-13 17:18:00 to 24-JUL-13 17:20:00 (CST-6)
Location: ORD
Magnitude: 1.75 
Property damage: 100.00K
Crop damage: 2.00M
Reported by: Law Enforcement

Thunderstorm Wind in VALLEY, NEBRASKA
From 24-JUL-13 17:18:00 to 24-JUL-13 17:18:00 (CST-6)
Location: (ODX)SHARP FLD ORD
Magnitude: 52.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Hail in VALLEY, NEBRASKA
From 24-JUL-13 17:30:00 to 24-JUL-13 17:30:00 (CST-6)
Location: NORTH LOUP
Magnitude: 1.25 
Property damage: 15.00K
Crop damage: 1.00M
Reported by: Public

Thunderstorm Wind in VALLEY, NEBRASKA
From 24-JUL-13 17:37:00 to 24-JUL-13 17:39:00 (CST-6)
Location: NORTH LOUP
Magnitude: 87.00 EG
Property damage: 150.00K
Crop damage: 2.00M
Reported by: NWS Storm Survey

A two story barn was heavily damaged, with one wall collapsed, by wind gusts estimated to be approaching 100 MPH.  A nearby home suffered minor siding damage.  A storage shed was moved from its foundation, being shoved up next to a power pole. Multiple grain bins also were damaged in the area, including one which was ripped from its foundation.

Thunderstorm Wind in VALLEY, NEBRASKA
From 24-JUL-13 17:20:00 to 24-JUL-13 17:20:00 (CST-6)
Location: ORD
Magnitude: 74.00 EG
Property damage: 40.00K
Crop damage: 2.00M
Reported by: NWS Storm Survey

Wind gusts estimated to be near 85 MPH resulted in roof damage at a home, with a 8 to 10 foot section being removed.  Some of the insulation was found in trees to the south of the home.

Thunderstorm Wind in HOWARD, NEBRASKA
From 24-JUL-13 18:28:00 to 24-JUL-13 18:28:00 (CST-6)
Location: BOELUS
Magnitude: 52.00 EG
Property damage: 75.00K
Crop damage: 5.00M
Reported by: Public

Wind gusts estimated at 60 MPH were accompanied by quarter to ping pong ball size hail.