A mesoscale convective complex moved out of central South Dakota and across northeast South Dakota late night, spurred by a strong low-level jet and elevated instability up to 3000 J/kg. Cells developing along the southern flank of this system quickly became severe with scattered reports of large hail and damaging wind.
Another cell developed midday behind the initial lines of convection, and produced a long swath of crop damage due to wind driven hail from south of Moneta, to near Everly and Spencer, to north of Ruthven.  A storm survey revealed that the hail damage varied from partial to nearly total crop devastation. While the width of the path was generally 2 to 3 miles, the path of devastation did vary up to 7 miles wide at one point north and west of Spencer.  Hail size varied from dime size to ping-pong ball size along the path.

Thunderstorm Wind in SIOUX, IOWA
From 27-JUN-19 07:55:00 to 27-JUN-19 07:55:00 (CST-6)
Location: HAWARDEN
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Large tree branch down.

Thunderstorm Wind in CLAY, IOWA
From 27-JUN-19 11:42:00 to 27-JUN-19 11:43:00 (CST-6)
Location: (3SE)SPENCER MUNI AR
Magnitude: 63.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Hail in LYON, IOWA
From 27-JUN-19 05:53:00 to 27-JUN-19 05:54:00 (CST-6)
Location: GEORGE
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Social Media

Hail in LYON, IOWA
From 27-JUN-19 06:00:00 to 27-JUN-19 06:02:00 (CST-6)
Location: GEORGE
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Social Media

Accompanied by strong winds and heavy rain.

Hail in LYON, IOWA
From 27-JUN-19 07:23:00 to 27-JUN-19 07:27:00 (CST-6)
Location: LOSTER
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Social Media

Hail in CLAY, IOWA
From 27-JUN-19 11:37:00 to 27-JUN-19 11:40:00 (CST-6)
Location: EVERLY
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in CLAY, IOWA
From 27-JUN-19 11:38:00 to 27-JUN-19 11:41:00 (CST-6)
Location: EVERLY
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail accompanied by estimated 50 mph winds.

Hail in CLAY, IOWA
From 27-JUN-19 11:43:00 to 27-JUN-19 11:46:00 (CST-6)
Location: (3SE)SPENCER MUNI AR
Magnitude: 1.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Social Media

Hail in CLAY, IOWA
From 27-JUN-19 11:46:00 to 27-JUN-19 11:49:00 (CST-6)
Location: SPENCER
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Hail in CLAY, IOWA
From 27-JUN-19 11:48:00 to 27-JUN-19 11:51:00 (CST-6)
Location: SPENCER
Magnitude: 1.25 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Social Media

Hail in CLAY, IOWA
From 27-JUN-19 11:50:00 to 27-JUN-19 11:53:00 (CST-6)
Location: SPENCER
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Social Media

Pea to nickel size with occasional quarter size.  Strong winds accompanied hail.

Thunderstorm Wind in LYON, IOWA
From 27-JUN-19 07:35:00 to 27-JUN-19 07:36:00 (CST-6)
Location: ROCK RAPIDS
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Large tree branches down.