As a strong upper level wave pushed into the western Dakotas during the evening hours, isolated supercellular storms developed across central South Dakota and moved through areas west of the James River. With 2000-2500 J/kg of MLCAPE and deep layer shear of 35 to 45 knots, the isolated storms produced hail up to golf ball size. Soon, an increasing amount of DCAPE of 1000-1250 J/kg and increase in 0-3 km shear with development of a strong low-level jet aided in the transition to enhanced linear structures, which then developed a series of mesovortices as the line moved into far eastern South Dakota, southwest Minnesota and northwest Iowa. Several brief tornadoes developed with mesovortices in southwest Minnesota and northwest Iowa, along with areas of enhanced wind damage.

Tornado in MURRAY, MINNESOTA
From 17-AUG-19 21:54:00 to 17-AUG-19 22:01:00 (CST-6)
Location: HADLEY
Tornado F-scale: EF1
Property damage: 200.00K
Reported by: NWS Storm Survey

The tornado formed around 2 miles west-southwest of Hadley, moving northeast through a farmstead shortly after touchdown and damaging trees and partially removing a roof from a metal outbuilding. After crossing Minnesota Highway 30, the tornado struck another farm, causing destruction of a barn, and resulting in damage to the house including blowing in a door and driving a 2x4 through the siding. The tornado reached Hadley three minutes after touchdown. Two garages were destroyed in town, along with damage to numerous trees. One final structure was grazed by the tornado just northeast of Hadley, blowing in the door and damaging the roof of a metal outbuilding. The tornado lifted around 2 miles northeast of Hadley after crossing 121st Street and damaging a power transmission pole. The average path width was 75 yards.

Thunderstorm Wind in COTTONWOOD, MINNESOTA
From 17-AUG-19 22:45:00 to 17-AUG-19 22:48:00 (CST-6)
Location: WINDOM
Magnitude: 56.00 EG
Reported by: Emergency Manager

Numerous tree branches taken down and were blocking the road at 12th Street and Miller Avenue on the east side of Windom.

Thunderstorm Wind in PIPESTONE, MINNESOTA
From 17-AUG-19 21:27:00 to 17-AUG-19 21:29:00 (CST-6)
Location: PIPESTONE
Magnitude: 52.00 EG
Reported by: Trained Spotter

Numerous power outages were reported around Pipestone with tree limbs down.

Thunderstorm Wind in MURRAY, MINNESOTA
From 17-AUG-19 22:50:00 to 17-AUG-19 22:53:00 (CST-6)
Location: DOVRAY
Magnitude: 51.00 MG
Reported by: Mesonet

Tornado in MURRAY, MINNESOTA
From 17-AUG-19 21:59:00 to 17-AUG-19 22:01:00 (CST-6)
Location: IONA
Tornado F-scale: EF0
Reported by: NWS Storm Survey

The tornado touched down a half mile south of Iona near the intersection of 140th Avenue and 41st Street, flattening a path across a corn field.  The tornado traveled northeast, and crossed 46th Street just east of Iona.  Near the end of its path, the tornado snapped three trees and topped several headstones in a cemetery. The average path width was 40 yards.

Tornado in NOBLES, MINNESOTA
From 17-AUG-19 21:59:00 to 17-AUG-19 22:03:00 (CST-6)
Location: READING
Tornado F-scale: EF0
Property damage: 10.00K
Reported by: NWS Storm Survey

A brief tornado spun up a mile and a half northwest of Reading, uprooting a tree and taking down several other branches. While most of the damage along the path toward the east-northeast was to trees and crops, one house had some minor damage with removal of a section of roofing material.  The average path width was 40 yards.

Tornado in MURRAY, MINNESOTA
From 17-AUG-19 22:08:00 to 17-AUG-19 22:10:00 (CST-6)
Location: CURRIE
Tornado F-scale: EF0
Property damage: 25.00K
Reported by: NWS Storm Survey

The track of this tornado followed generally eastward along 181st Street between 140th and 150th Avenues. The tornado started with a slight south of east track, flattening corn and damaging trees in a shelter belt.  The tornado then began to move more eastward, striking and destroying an old barn around a quarter mile from the touchdown point.  The remainder of the track was across cornfields, crossing north of 181st Street before lifting.  The average path width was 40 yards.

Tornado in MURRAY, MINNESOTA
From 17-AUG-19 22:14:00 to 17-AUG-19 22:16:00 (CST-6)
Location: CURRIE
Tornado F-scale: EF0
Property damage: 50.00K
Reported by: NWS Storm Survey

This brief tornado touched down around a mile south of Lake Sarah in an open corn field, leaving a discernible track. Two small outbuildings were damaged as the tornado moved to the northeast, with mainly minor damage to metal roofing panels. The tornado crossed U.S. Highway 59, turning a bit more northward in track before damaging the final farm outbuilding and lifting shortly thereafter. The average path width was 30 yards.

Tornado in COTTONWOOD, MINNESOTA
From 17-AUG-19 22:25:00 to 17-AUG-19 22:26:00 (CST-6)
Location: WINDOM
Tornado F-scale: EF0
Reported by: Public

The brief tornado spun up around 7 miles west of Windom, crossing Minnesota Highway 62 near 410th Avenue. Corn was flattened and shredded along the half-mile path toward the north and northeast. The average path width was 10 yards.

Thunderstorm Wind in NOBLES, MINNESOTA
From 17-AUG-19 21:46:00 to 17-AUG-19 21:48:00 (CST-6)
Location: LEOTA
Magnitude: 56.00 EG
Reported by: NWS Storm Survey

Several large branches were taken down by thunderstorm winds.

Thunderstorm Wind in NOBLES, MINNESOTA
From 17-AUG-19 21:48:00 to 17-AUG-19 21:51:00 (CST-6)
Location: LEOTA
Magnitude: 70.00 EG
Reported by: Public

A garage was blown off its foundation and numerous large branches removed by outflow winds.

Thunderstorm Wind in NOBLES, MINNESOTA
From 17-AUG-19 21:53:00 to 17-AUG-19 21:55:00 (CST-6)
Location: WILMONT
Magnitude: 61.00 EG
Reported by: Social Media

Power lines were taken down by strong thunderstorm winds.

Thunderstorm Wind in MURRAY, MINNESOTA
From 17-AUG-19 21:54:00 to 17-AUG-19 21:56:00 (CST-6)
Location: CHANDLER
Magnitude: 55.00 EG
Property damage: 10.00K
Reported by: NWS Storm Survey

Thunderstorm winds flipped an old shed toward the north.