Thunderstorms brought heavy rain and a landspout to portions of south central Nebraska the evening of Sunday, May 24 into the early morning hours of Memorial Day, Monday, May 25.
Just after 6 PM CDT Sunday evening, weak thundershowers began developing along a frontal boundary that was located from near Stockton, KS to Red Cloud, NE to Shelby, NE. One of these weak thundershowers managed to spawn a landspout tornado a few miles west of Davenport, NE, in extreme northeastern portions of Nuckolls County. This landspout, unlike most, did cause some damage as nearly a dozen empty coal railroad cars were overturned. The aforementioned line of thunderstorms strengthened slightly during the evening, per radar reflectivity, before weakening with loss of daytime heating around sunset. The landspout was the only known severe weather caused by this line of thunderstorms as the main focus for severe convection remained further south across Kansas near the Interstate 70 corridor.
Showers and thunderstorms blossomed over south central Nebraska and north central Kansas after 10 PM Sunday and continued through the entire overnight. This activity remained non-severe, but very slow storm motions and abundant deep layer moisture allowed for heavy rain rates and, subsequently, pockets of very heavy rainfall. The heaviest rainfall amounts of 4 to 8 inches (per radar and ground truth observations) appeared to focus across northwest Adams County and southwest Hall County. Numerous county roads became submerged in water and impassable late Sunday night into early Monday morning. The most severe impact, however, was to a residence northwest of Kenesaw as flood water filled the basement and even encroached on the main floor, prompting their rescue early Monday morning. The rescue had to be done via air boat because so many roads in the area were under water and impassable.
The heavy rain from Sunday night into Monday morning occurred over areas that were already saturated from recent heavy rains from May 21-23, and this likely contributed to the flooding impacts from this event. Very slow storm motions and seasonably high precipitable water values near 1.5��� were also meteorological factors to this heavy rain event. The tornado occurred in conditions fairly typical of landspouts as it was along a surface front with abundant ambient vorticity that was stretched into the vertical axis by steep low level lapse rates and sufficient 0-3 km CAPE near 100 J/kg.

Tornado in NUCKOLLS, NEBRASKA
From 24-MAY-20 17:26:00 to 24-MAY-20 17:36:00 (CST-6)
Location: OAK
Tornado F-scale: EF0
Property damage: 15.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

A landspout tornado was confirmed via several eyewitness reports and a damage survey in northern Nuckolls County. This tornado formed along a weak frontal boundary and exhibited the classic landspout characteristics of a long, translucent condensation/dust funnel. The landspout moved southwest along the boundary for over 3 miles. The main damage along its path was the overturning of 11 empty coal railroad cars. Otherwise, damage was minimal. The maximum wind speed was estimated to be 80 MPH.

Flash Flood in ADAMS, NEBRASKA
From 25-MAY-20 00:00:00 to 25-MAY-20 09:00:00 (CST-6)
Location: KENESAW
Flood cause: Heavy Rain
Property damage: 100.00K
Crop damage: 1.00M
Reported by: Emergency Manager

Radar estimates depicted an area of approximately 4 to 8 inches of rain fell in a very concentrated area across far southwestern portions of Hall County and far northwestern portions of Adams County. Numerous rural roads were covered in water and impassable for a period of time. A home just northwest of Kenesaw was flooded, and the residents had to be rescued. Due to road conditions, the rescue was not completed until daybreak on the 25th, and was done by airboat.

Flash Flood in HALL, NEBRASKA
From 25-MAY-20 00:00:00 to 25-MAY-20 09:00:00 (CST-6)
Location: WOOD RIVER
Flood cause: Heavy Rain
Property damage: 100.00K
Crop damage: 1.00M
Reported by: Emergency Manager

Radar estimates depicted an area of approximately 4 to 8 inches of rain fell in a very concentrated area across far southwestern portions of Hall County and far northwestern portions of Adams County. Numerous rural roads were covered in water and impassable for a period of time. At least 19 roads were marked with barricades and at least 1 culvert was lost. A number of roads were washed out pretty well, materials like dirt, crushed concrete and gravel were needed for repairs.