One long-tracked supercell thunderstorm, and several other shorter-lived storms spawned tornadoes across eastern Nebraska during the late afternoon and evening hours of May 11th.  The storms developed near the intersection of a warm front and dry-line/cold front in south central Nebraska then tracked northeast along the warm front toward the Lincoln and Omaha areas.   Conditions in the area were very unstable with temperatures in the 80s to around 90 south of the warm front with dew point temperatures in the 60s.  In total 12 tornadoes were recorded in the Omaha/Valley warning area with several others in the Hastings forecast area. The storms also produced very heavy rainfall which caused some flooding, mostly north through west and southwest of Lincoln.

Tornado in JEFFERSON, NEBRASKA
From 11-MAY-14 17:55:00 to 11-MAY-14 18:02:00 (CST-6)
Location: DAYKIN
Tornado F-scale: EF1
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

This tornado developed in open country southeast of Daykin and traveled northeast into Saline county with a total track of 15.5 miles (5.8 miles in Jefferson county).

Flash Flood in LANCASTER, NEBRASKA
From 11-MAY-14 19:50:00 to 11-MAY-14 20:50:00 (CST-6)
Location: ARROW ARPT
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Heavy rain caused flash flooding across parts of north Lincoln, including across 44th Street near Cornhusker Highway.

Flash Flood in SAUNDERS, NEBRASKA
From 11-MAY-14 19:34:00 to 11-MAY-14 20:34:00 (CST-6)
Location: CERESCO
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Heavy rain caused brief flash flooding of a few roads in the Ceresco area.

Thunderstorm Wind in DOUGLAS, NEBRASKA
From 11-MAY-14 18:51:00 to 11-MAY-14 18:51:00 (CST-6)
Location: OMAHA
Magnitude: 71.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

The Asos at Omaha-Eppley Airfield measured a thunderstorm wind gust at 82 mph.

Thunderstorm Wind in DOUGLAS, NEBRASKA
From 11-MAY-14 19:20:00 to 11-MAY-14 19:20:00 (CST-6)
Location: DUNDEE
Magnitude: 60.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Thunderstorm wind gusts estimated at around 70 mph downed 18 to 24 inch diameter tree limbs in the Benson area between 72nd and 60th Streets.

Thunderstorm Wind in DOUGLAS, NEBRASKA
From 11-MAY-14 18:30:00 to 11-MAY-14 18:30:00 (CST-6)
Location: GIBSON
Magnitude: 55.00 EG
Crop damage: 0.00K
Reported by: Broadcast Media

Thunderstorm wind gusts estimated at over 60 mph downed a large tree on a home near 38th and Leavenworth.

Tornado in DOUGLAS, NEBRASKA
From 11-MAY-14 18:07:00 to 11-MAY-14 18:25:00 (CST-6)
Location: WATERLOO
Tornado F-scale: EF1
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Amateur Radio

This tornado initially touched down in Saunders county and had a total track length of around 10.7 miles with around 7 miles of the track in Douglas county.  This was the first of 2 tornadoes that hit near the Omaha area this evening.

Flood in SEWARD, NEBRASKA
From 12-MAY-14 09:00:00 to 13-MAY-14 17:00:00 (CST-6)
Location: BEAVER CROSSING ARPT
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

Heavy rain from storms on May 11th caused the West Fork of the Blue River to flood several county roads and farm lowlands around Beaver Crossing.  Other than washing some gravel off the roads, the flooding caused little apparent damage.

Tornado in DOUGLAS, NEBRASKA
From 11-MAY-14 18:21:00 to 11-MAY-14 18:27:00 (CST-6)
Location: ELKHORN
Tornado F-scale: EF1
Property damage: 0.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

This tornado was the second of two tornadoes that hit near the Omaha area this evening.  The track of this tornado was around 5 miles.

Flash Flood in LANCASTER, NEBRASKA
From 11-MAY-14 19:00:00 to 11-MAY-14 20:30:00 (CST-6)
Location: RAYMOND
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Heavy rain flooded a creek causing the brief closure of Raymond Road a little west of 1st Street.  Other than washing off some gravel, little damage was noted from the flooding.

Flood in SEWARD, NEBRASKA
From 11-MAY-14 18:00:00 to 14-MAY-14 06:00:00 (CST-6)
Location: SEWARD
Flood cause: Heavy Rain
Property damage: 2.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Heavy rain caused flooding along Lincoln Creek near and northwest of Seward.  The creek reached a little over 18.5 feet during this time, flood stage is 15 feet.  The flooding impacted surrounding farm fields and closed several roads in the area.

Flood in SALINE, NEBRASKA
From 12-MAY-14 21:45:00 to 15-MAY-14 07:00:00 (CST-6)
Location: SHESTAK
Flood cause: Heavy Rain
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Heavy rain caused flooding along the Big Blue River near Crete and most likely upstream through it's confluence with the West Fork of the Big Blue.  The river level near Crete reached a little over 23 feet during this time, flood stage is 18 feet.  The flooding impacted county roads and farmland near the river.

Tornado in SALINE, NEBRASKA
From 11-MAY-14 18:02:00 to 11-MAY-14 18:15:00 (CST-6)
Location: WESTERN
Tornado F-scale: EF1
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

This tornado initially touched down in Jefferson county and tracked around 15.5 miles in total (nearly 10 of them in Saline county).

Tornado in SAUNDERS, NEBRASKA
From 11-MAY-14 17:42:00 to 11-MAY-14 17:45:00 (CST-6)
Location: CERESCO
Tornado F-scale: EF0
Property damage: 0.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

This tornado had a track of a little under 2 miles.

Tornado in SAUNDERS, NEBRASKA
From 11-MAY-14 17:59:00 to 11-MAY-14 18:07:00 (CST-6)
Location: WANN
Tornado F-scale: EF1
Property damage: 0.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

This tornado initially touched down south of Yutan in Saunders county and crossed over into Douglas county.  The total path length was about 10.7 miles, a little under 4 of it in Saunders county.

Hail in GAGE, NEBRASKA
From 11-MAY-14 19:30:00 to 11-MAY-14 19:30:00 (CST-6)
Location: CORTLAND
Magnitude: 2.75 
Reported by: Trained Spotter

Hail a little under 3 inches in diameter was reported south of Cortland.

Hail in OTOE, NEBRASKA
From 11-MAY-14 19:56:00 to 11-MAY-14 19:56:00 (CST-6)
Location: DOUGLAS
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A little north of Douglas along the county spur.

Thunderstorm Wind in SEWARD, NEBRASKA
From 11-MAY-14 17:01:00 to 11-MAY-14 17:01:00 (CST-6)
Location: RUBY
Magnitude: 78.00 EG
Reported by: Trained Spotter

Thunderstorm winds were estimated at between 85 and 90 mph near the I80 interchange north of Milford.  The winds were possibly outflow from the rear flank downdraft with the supercell thunderstorm that produced several tornadoes in the region.

Flash Flood in SAUNDERS, NEBRASKA
From 11-MAY-14 18:15:00 to 11-MAY-14 20:15:00 (CST-6)
Location: ITHACA
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Fire Department/Rescue

Flash flooding briefly closed the intersection of County Rd 14 and Highway 66.

Thunderstorm Wind in SAUNDERS, NEBRASKA
From 11-MAY-14 17:56:00 to 11-MAY-14 17:56:00 (CST-6)
Location: MEMPHIS
Magnitude: 56.00 EG
Reported by: Emergency Manager

Thunderstorm winds estimated at 60 to 70 mph and zero visibility in heavy rain was reported a little east of Memphis.

Flood in SAUNDERS, NEBRASKA
From 12-MAY-14 00:00:00 to 12-MAY-14 18:00:00 (CST-6)
Location: WAHOO
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Heavy rain caused flooding along Wahoo Creek from near old Highway 77 south of Wahoo, to near Ithaca then toward Ashland.  The flooding impacted a few county roads and farm fields near the creek.  At Ithaca the creek reached around 20 feet during this time, flood stage is 19 feet.

Flash Flood in SEWARD, NEBRASKA
From 11-MAY-14 18:00:00 to 11-MAY-14 20:00:00 (CST-6)
Location: KRUTZ ARPT
Flood cause: Heavy Rain
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Newspaper

Heavy rain caused flash flooding across several streets in the Seward area. Some vehicles were stalled in the flood waters and several basements were flooded.

Thunderstorm Wind in LANCASTER, NEBRASKA
From 11-MAY-14 17:50:00 to 11-MAY-14 17:50:00 (CST-6)
Location: WEST LINCOLN
Magnitude: 65.00 MG
Crop damage: 0.00K
Reported by: Trained Spotter

A spotter measured a thunderstorm wind gust at 75 mph about 1.5 miles east of the Lincoln airport.  The strong winds downed trees in the area.

Thunderstorm Wind in DOUGLAS, NEBRASKA
From 11-MAY-14 18:35:00 to 11-MAY-14 18:35:00 (CST-6)
Location: MILLARD
Magnitude: 63.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

The Awos at the Millard airport recorded a thunderstorm wind gust of 72 mph.

Flood in SEWARD, NEBRASKA
From 12-MAY-14 09:00:00 to 12-MAY-14 18:00:00 (CST-6)
Location: SEWARD
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Heavy rain caused flooding along Lincoln Creek and the Big Blue River near Seward.  Although most of the flooding was observed along Lincoln Creek, the Big Blue River near Seward did briefly just cross it's 18 foot flood stage.  A few county roads and farm fields along the River were impacted.

Tornado in SEWARD, NEBRASKA
From 11-MAY-14 16:23:00 to 11-MAY-14 16:38:00 (CST-6)
Location: BEAVER CROSSING
Tornado F-scale: EF2
Property damage: 0.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

This tornado developed rapidly after the Beaver Crossing tornado as the supercell continued to move northeast. The tornado quickly strengthened to EF2 and completed destroyed several large outbuildings as it crossed Pioneers and Van Dorn Roads. The tornado turned more northeast as it crossed A street downing power lines and snapping trees. The tornado crossed Interstate 80 about a half mile west of the of the Highway 15 interchange where a semi tractor trailer was overturned. The tornado weakened and turned east as it moved north of the Interstate and produced mainly minor tree and power line damage.

Tornado in SEWARD, NEBRASKA
From 11-MAY-14 16:13:00 to 11-MAY-14 16:19:00 (CST-6)
Location: BEAVER CROSSING ARPT
Tornado F-scale: EF0
Property damage: 0.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

This was a satellite tornado of the larger Beaver Crossing tornado. This tornado was filmed by storm chasers in the area. The tornado was responsible for minor tree damage to the northwest of the city of Beaver Crossing.

Tornado in SEWARD, NEBRASKA
From 11-MAY-14 17:01:00 to 11-MAY-14 17:10:00 (CST-6)
Location: CORDOVA
Tornado F-scale: EF1
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

This tornado crossed into Seward county from York county and was from a trailing supercell thunderstorm that followed the storm that produced an EF3 tornado just to the south a little earlier. This tornado was responsible snapping several power poles as it entered into Seward County along 476th street. The tornado continued northeast producing occasional tree damage, tipping over center pivot irrigation equipment, and outbuilding damage.

Thunderstorm Wind in SEWARD, NEBRASKA
From 11-MAY-14 16:08:00 to 11-MAY-14 16:20:00 (CST-6)
Location: CORDOVA
Magnitude: 90.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

A wide swath of straight line wind damage was noted to the south of the track of the tornado associated with the rear-flank downdraft. This damage included areas from near Cardova northeast to southeast of Beaver Crossing and was nearly 4 miles wide at times. The damage surveyed was consistent with winds greater than 100 mph. The damage included downed power poles, completely destroyed outbuildings at numerous farmsteads, numerous center pivots flipped and trees uprooted and snapped.

Tornado in SEWARD, NEBRASKA
From 11-MAY-14 16:53:00 to 11-MAY-14 17:05:00 (CST-6)
Location: RUBY
Tornado F-scale: EF2
Property damage: 0.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

This tornado initially touched down southwest of Garland and was from the same supercell thunderstorm that produced the EF3 tornado that hit Beaver Crossing. Soon after this tornado developed it moved through a newly developed areas of homes along Sunset Rd to the southwest of Garland. Here the tornado was responsible for completely destroying several well built large outbuildings. In addition the tornado damaged two homes where the roofs were partially removed, as well downing numerous trees in this area. The tornado continued east along US Highway 34 while weakening, but still damaging small outbuildings and breaking tree limbs.

Tornado in LANCASTER, NEBRASKA
From 11-MAY-14 17:07:00 to 11-MAY-14 17:13:00 (CST-6)
Location: MALCOLM
Tornado F-scale: EF1
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

This tornado developed between Waverly Road and Bluff Road west of NW 140th Street.  The track was around 3 miles. The tornado appeared to be at peak intensity as it crossed Northwest 126th Street where a farmstead was significantly impacted with multiple outbuildings completely destroyed and minor roof damage to the house. Numerous hard wood trees were snapped in this area, and a hay bail was thrown nearly a half mile.

Tornado in LANCASTER, NEBRASKA
From 11-MAY-14 17:20:00 to 11-MAY-14 17:30:00 (CST-6)
Location: RAYMOND
Tornado F-scale: EF1
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

This was the second tornado to track near the Raymond area from this event.  This particular tornado had a path length of around 5.3 miles. The tornado was generally weak throughout the path but did remove the roof from a well built large outbuilding as it crossed North 14th Street at Branch Oak Road. Otherwise damage was confined to mainly tree damage.

Tornado in SEWARD, NEBRASKA
From 11-MAY-14 16:08:00 to 11-MAY-14 16:28:00 (CST-6)
Location: CORDOVA
Tornado F-scale: EF3
Property damage: 2.40M
Crop damage: 0.00K
Reported by: Law Enforcement

This tornado crossed into Seward county from York county and was the most intense tornado during this outbreak with a track of around 14 miles in Seward county. The tornado moved just north of the city of Cordova crossing State Highway 76A. Here the tornado impacted several rural residents. High end EF2 damage was done to one brick home where the roof was completely removed and some external walls were knocked down. The tornado continued northeast crossing Yankee Hill Rd less than a mile from State Highway 76A, and this is where the most significant damage occurred. Here a well built brick home had the roof completely removed, exterior walls knocked down, and a couple of interior walls downed as well. The tornado continued northeast while widening, but generally decreasing in intensity as it crossed Denton and Old Cheney Roads. The tornado reached its maximum width to the southwest of Beaver Crossing before moving directly into town. Widespread damage was observed in Beaver Crossing with nearly every structure in town sustaining some damage. In the city scattered EF2 damage was noted with several structures having thier roofs removed. Otherwise most of the damage was tree, power line and outbuildings being destroyed. The tornado exited Beaver Crossing and moved northeast while decreasing in width and intensity eventually dissipating less than 1 mile south of Interstate 80.

Tornado in LANCASTER, NEBRASKA
From 11-MAY-14 17:11:00 to 11-MAY-14 17:20:00 (CST-6)
Location: RAYMOND
Tornado F-scale: EF2
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

This was the first and stronger of the two tornadoes that tracked near the Raymond area.  This track was around 2.5 miles long. Although relatively short in length, this tornado impacted several farmsteads along its path. The first of these was as it crossed Northwest 48th Street where some structural damage was done to a home. The tornado increased in intensity as it reached Northwest 40th Street where a well built garage was completely destroyed and a camper was rolled over 100 yards. The tornado reached maximum intensity as it crossed Northwest 12th Street where the roof was partially removed from a home. In addition, outbuildings were completely destroyed and farm machinery was tossed at this location. The tornado quickly dissipated after this location.

Thunderstorm Wind in GAGE, NEBRASKA
From 11-MAY-14 18:25:00 to 11-MAY-14 18:25:00 (CST-6)
Location: CLATONIA
Magnitude: 60.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Thunderstorm wind gusts estimated at around 70 mph damaged grain bins and outbuildings northeast of Clatonia.

Flash Flood in LANCASTER, NEBRASKA
From 12-MAY-14 01:30:00 to 12-MAY-14 02:55:00 (CST-6)
Location: WAVERLY
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Heavy rain caused flash flooding along Rock Creek in northeast Lancaster county.  The flooding impacted county roads and farm fields along the creek.

Flash Flood in DOUGLAS, NEBRASKA
From 11-MAY-14 19:30:00 to 11-MAY-14 20:30:00 (CST-6)
Location: MILLARD
Flood cause: Heavy Rain
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Department of Highways

Heavy rain caused localized flash flooding in parts of west Omaha, including near 119th and Pacific Streets where 1 car was stranded due to flood waters.

Flash Flood in SAUNDERS, NEBRASKA
From 11-MAY-14 19:19:00 to 11-MAY-14 21:19:00 (CST-6)
Location: ITHACA
Flood cause: Heavy Rain
Property damage: 2.00K
Crop damage: 0.00K
Reported by: Fire Department/Rescue

Several roads around Ithica were briefly closed due to flash flooding.

Flood in LANCASTER, NEBRASKA
From 12-MAY-14 02:55:00 to 12-MAY-14 09:55:00 (CST-6)
Location: CERESCO
Flood cause: Heavy Rain
Property damage: 3.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Heavy rain caused flooding along Rock Creek near Ceresco.  The stream reached a little over 24 feet during the early morning hours of 5/12, flood stage is 22 feet.  The flooding mainly impacted a few farm fields and county roads near the creek.  Damage was apparently minimal.