An unseasonably strong mid and upper level jet combined with high amounts of low level moisture and instability to create a volatile atmosphere across eastern Nebraska and western Iowa late in the night and into Monday morning. Thunderstorms developed on the nose of the low-level jet and quickly became severe. Isolated to scattered supercells moved across northeast Nebraska and western Iowa through late morning before exiting into central Iowa.

Hail in POTTAWATTAMIE, IOWA
From 30-JUN-14 06:49:00 to 30-JUN-14 06:49:00 (CST-6)
Location: CRESCENT
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in POTTAWATTAMIE, IOWA
From 30-JUN-14 07:06:00 to 30-JUN-14 07:06:00 (CST-6)
Location: UNDERWOOD
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Fire Department/Rescue

Hail in POTTAWATTAMIE, IOWA
From 30-JUN-14 08:00:00 to 30-JUN-14 08:00:00 (CST-6)
Location: WALNUT
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Hail in SHELBY, IOWA
From 30-JUN-14 08:00:00 to 30-JUN-14 08:00:00 (CST-6)
Location: PORTSMOUTH
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in SHELBY, IOWA
From 30-JUN-14 08:10:00 to 30-JUN-14 08:10:00 (CST-6)
Location: TENNANT
Magnitude: 1.25 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Hail in POTTAWATTAMIE, IOWA
From 30-JUN-14 10:58:00 to 30-JUN-14 10:58:00 (CST-6)
Location: WALNUT
Magnitude: 1.25 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Thunderstorm Wind in HARRISON, IOWA
From 30-JUN-14 10:05:00 to 30-JUN-14 10:05:00 (CST-6)
Location: RIVER SIOUX
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

The observer estimated 60 mph winds and pea size hail.

Flash Flood in MONONA, IOWA
From 30-JUN-14 10:30:00 to 30-JUN-14 11:00:00 (CST-6)
Location: MAPLETON
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Water was reported running over county roads in an area from Whiting to Rodney. There was also street flooding reported in the town of Mapleton.

Flash Flood in MONONA, IOWA
From 30-JUN-14 10:45:00 to 30-JUN-14 10:45:00 (CST-6)
Location: MAPLETON
Flood cause: Heavy Rain
Property damage: 50.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Heavy rainfall caused several inches of water on roads in the city of Mapleton, as well as on the county roads outside of town. Rainfall of 1.80 inches was reported in a half hour leading to the flash flooding.

Flash Flood in SHELBY, IOWA
From 30-JUN-14 12:00:00 to 30-JUN-14 12:00:00 (CST-6)
Location: HARLAN
Flood cause: Heavy Rain
Property damage: 50.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Local law enforcement reported that many county roads had water flowing across them in low spots. There was also street flooding reported in the city of Harlan.

Hail in SHELBY, IOWA
From 30-JUN-14 08:18:00 to 30-JUN-14 08:27:00 (CST-6)
Location: HARLAN
Magnitude: 3.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Numerous reports of large hail were received in and just to the south of the city of Harlan. The hail ranged from around quarter size to 3 inches in diameter. The hail was responsible for damage to windows, cars and roofs in and around town.

Flash Flood in SHELBY, IOWA
From 30-JUN-14 12:00:00 to 30-JUN-14 12:30:00 (CST-6)
Location: HARLAN
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Street flooding was widespread in the city of Harlan. Water was also reported across many county roads outside of town as well.