A weak upper-level disturbance tracked from the central High Plains through the mid Missouri Valley, encouraging the development of a surface low from southeast South Dakota into eastern Nebraska.  Meanwhile, an associated cold front progressed east into eastern Nebraska by afternoon with a stationary boundary extending from the surface low through southwest Iowa into northern Missouri. Severe thunderstorms developed during the late afternoon over eastern Nebraska and southwest Iowa along these surface features with activity merging into a bow-echo complex that subsequently tracked into northwest Missouri by late evening. Brief tornadoes occurred  with a supercell over Cass County, NE  with intense, straight-line winds affecting the I-29 corridor in Fremont County, IA.

Thunderstorm Wind in POTTAWATTAMIE, IOWA
From 11-JUN-18 18:01:00 to 11-JUN-18 18:01:00 (CST-6)
Location: CARSON
Magnitude: 55.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Thunderstorm Wind in FREMONT, IOWA
From 11-JUN-18 18:10:00 to 11-JUN-18 18:10:00 (CST-6)
Location: THURMAN
Magnitude: 76.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Thunderstorm Wind in FREMONT, IOWA
From 11-JUN-18 18:22:00 to 11-JUN-18 18:22:00 (CST-6)
Location: SIDNEY
Magnitude: 63.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Thunderstorm Wind in PAGE, IOWA
From 11-JUN-18 18:35:00 to 11-JUN-18 18:35:00 (CST-6)
Location: SHENANDOAH
Magnitude: 61.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Thunderstorm Wind in MONTGOMERY, IOWA
From 11-JUN-18 18:38:00 to 11-JUN-18 18:38:00 (CST-6)
Location: RED OAK
Magnitude: 50.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Thunderstorm Wind in PAGE, IOWA
From 11-JUN-18 19:01:00 to 11-JUN-18 19:01:00 (CST-6)
Location: CLARINDA
Magnitude: 54.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Thunderstorm Wind in PAGE, IOWA
From 11-JUN-18 19:15:00 to 11-JUN-18 19:15:00 (CST-6)
Location: CLARINDA MUNI ARPT
Magnitude: 55.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Thunderstorm Wind in FREMONT, IOWA
From 11-JUN-18 18:38:00 to 11-JUN-18 18:38:00 (CST-6)
Location: SHENANDOAH
Magnitude: 60.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Thunderstorm Wind in PAGE, IOWA
From 11-JUN-18 19:03:00 to 11-JUN-18 19:03:00 (CST-6)
Location: CLARINDA
Magnitude: 59.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Tornado in FREMONT, IOWA
From 11-JUN-18 17:59:00 to 11-JUN-18 18:00:00 (CST-6)
Location: MC PAUL
Tornado F-scale: EF0
Property damage: 0.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

Tree damage from embedded tornado.  Large tree limbs down from tops of elm and oak trees.  Empty tractor trailer was moved from its mooring blocks.

Thunderstorm Wind in FREMONT, IOWA
From 11-JUN-18 18:15:00 to 11-JUN-18 18:15:00 (CST-6)
Location: PERCIVAL
Magnitude: 65.00 EG
Reported by: Public

Three farm storage buildings were destroyed 3 miles south of Thurman.

Thunderstorm Wind in FREMONT, IOWA
From 11-JUN-18 18:00:00 to 11-JUN-18 18:00:00 (CST-6)
Location: MC PAUL
Magnitude: 75.00 EG
Reported by: Storm Chaser

A total of 9 semi-trucks were overturned on Interstate 29  west of Thurman.  Two drivers were injured and taken by ambulance to a hospital. Interstate 29 was closed in both directions after the damaging wind gust overturned the trucks. Numerous trees and power lines were down west of Thurman. In Thurman, there were a lot of trees uprooted along with damage to roofs of homes.

Thunderstorm Wind in MONTGOMERY, IOWA
From 11-JUN-18 18:28:00 to 11-JUN-18 18:28:00 (CST-6)
Location: COBURG
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Shingles blown off homes and small tree limbs blown down.