Although widespread thunderstorm activity affected most all of South Central Nebraska from the evening hours of Friday the 8th into the early morning of Saturday the 9th, there were only a handful of severe-criteria hail and wind reports from western counties including estimated 60 MPH winds in the Minden and Arapahoe areas, quarter size hail in Kearney and hail up to golf ball size in central Dawson County. However, the biggest story of the night turned out to be locally heavy rainfall. While much of the 24-county area received generally 1-2 inches of rain with little to no flooding issues, isolated pockets were drenched with 3-4 in a short time. One of these smaller zones of torrential rain happened to strike the city of Kearney, resulting in one of its worst flash flooding events in several years. Although unofficial reports suggested higher amounts may have fallen in the city, a few of the most reliable gauge readings featured storm totals of 3.89 in the southwestern part of town (NeRAIN observer) and 3.19 at Kearney Regional Airport (NWS cooperative observer). The majority of this rain fell within one hour between 11 pm-12 am CDT, in association with a supercell storm anchoring the western side of a southward-sinking squall line. As a result, significant urban street flooding ensued, stranding at least one to two dozen cars in water up to around 3 feet deep. However, the most newsworthy incident of the night occurred at Good Samaritan Hospital, where water broke through two-story, ground-to-ceiling windows of the cafeteria, allowing water to rush into the building. Flood waters also breached the hospital's basement, and water damage occurred in other portions of the main building. Fortunately, no hospital patients or employees were injured.
Taking a closer look at the timing and evolution of this event, strong to severe storms initially flared up well-north of the local area near the Nebraska-South Dakota border during the mid-to-late afternoon hours. This area of convection eventually grew upscale into a southeastward-moving squall line which first entered northern portions of South Central Nebraska between 830-1000 pm CDT. Along the western edge of this convective line, a semi-discrete supercell storm organized near the intersection of Dawson-Buffalo-Custer counties around 10 pm CDT. This intense storm then drifted southeastward through much of Buffalo County before weakening over Kearney County, but not before producing the Kearney flash flooding. As this supercell was affecting the Kearney area, a separate and smaller north-south oriented squall line moved into the local area out of southwestern Nebraska, affecting several western counties mainly between 11 pm-1 am CDT and yielding a few reports of marginally severe wind gusts mainly in Furnas and Harlan counties. By around 1 am CDT, both initial convective clusters had weakened enough that it appeared the rest of the night would feature only sub-severe showers and storms. However, during the 3-5 am CDT time frame a pair of isolated severe storms flared up west of the departing larger-scale precipitation shield, likely along an elevated outflow boundary. The southern of these storms reached peak intensity along the Phelps-Harlan county line but yielded no verifying storm reports, while the northern one affected primarily central Dawson County with hail up to golf ball size before dissipating around 530 am CDT.
This low-end severe weather and isolated flash flooding event was not very synoptically-evident in the hours leading up to it, thanks mainly to the lack of a notable mid-upper level disturbance and surface front. The initial storm development north of the local area appeared tied to a subtle mid level disturbance passing through otherwise typical, late-summer quasi-zonal flow featuring 0-6 kilometer deep layer wind shear generally no more than 30 knots. However, once storms became organized and moved into South Central Nebraska toward sunset they were sustained by respectable most-unstable CAPE on the order of 1000-2000 J/kg, as convective outflow promoted renewed storm development in a moist environment featuring surface dewpoints well into the 60s F. In addition, this nocturnal event was aided by the development of a modest 20-30 knot southwesterly low level jet evident around 850 millibars.

Thunderstorm Wind in FURNAS, NEBRASKA
From 08-AUG-14 22:53:00 to 08-AUG-14 22:53:00 (CST-6)
Location: ARAPAHOE
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A thunderstorm wind gust was estimated to be 60 mph.

Thunderstorm Wind in HARLAN, NEBRASKA
From 08-AUG-14 23:10:00 to 08-AUG-14 23:10:00 (CST-6)
Location: OXFORD
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A thunderstorm wind gust of 60 mph was estimated to occur along the leading edge of a gust front, just ahead of an approaching thunderstorm. This occurred on the east side of Oxford.

Flash Flood in BUFFALO, NEBRASKA
From 08-AUG-14 22:55:00 to 09-AUG-14 02:00:00 (CST-6)
Location: KEARNEY
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Newspaper

Stalled cars with flooding was observed on many streets across Kearney, with an estimate of 15 to 20 stalled cars. The sewer system of Kearney was overwhelmed and water broke through the two-story ground-to-ceiling windows of a dining room to Good Samaritan Hospital. Some of the windows were broken. The hospital basement was flooded, and there was water damage in other portions of the hospital. Rainfall was later measured to be around 3.5 inches.

Hail in BUFFALO, NEBRASKA
From 08-AUG-14 21:40:00 to 08-AUG-14 21:40:00 (CST-6)
Location: AMHERST
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Wind gusts of 50 mph occurred along with the quarter size hail.

Hail in BUFFALO, NEBRASKA
From 08-AUG-14 22:15:00 to 08-AUG-14 22:15:00 (CST-6)
Location: KEARNEY
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Wind gusts up to 30 mph occurred along with the quarter size hail, which was falling at the time of the report.

Hail in DAWSON, NEBRASKA
From 09-AUG-14 03:42:00 to 09-AUG-14 03:42:00 (CST-6)
Location: DARR
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

This report, along with a photo, was received on Facebook.

Heavy Rain in BUFFALO, NEBRASKA
From 08-AUG-14 22:00:00 to 09-AUG-14 05:00:00 (CST-6)
Location: KEARNEY
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

This storm total rainfall was 3.89 inches, and was the 24 hour total, ending the morning of August 9th, with the majority of rain falling between 10 pm CDT and 3 am CDT. This report was received via the NERAIN network.

Heavy Rain in BUFFALO, NEBRASKA
From 08-AUG-14 22:00:00 to 09-AUG-14 05:00:00 (CST-6)
Location: KEARNEY
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

This storm total rainfall was 3.30 inches, and was the 24 hour total, ending the morning of August 9th. The majority of rain fell between 11 pm CDT and 3 am CDT. This report was received via the NERAIN network.

Heavy Rain in BUFFALO, NEBRASKA
From 08-AUG-14 21:00:00 to 09-AUG-14 06:00:00 (CST-6)
Location: RIVERDALE
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

This 24-hour storm total rainfall was 3.22 inches, with most of the rain falling between 10 pm CDT and 3 am CDT. This report was received via the NERAIN network.

Heavy Rain in BUFFALO, NEBRASKA
From 08-AUG-14 06:00:00 to 09-AUG-14 06:00:00 (CST-6)
Location: (EAR)KEARNEY ARPT
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

This storm total rainfall was 3.19 inches, and was the 24 hour total, ending the morning of August 9th. This is the official Kearney 24-hour rainfall total from the NWS Cooperative Observer at the airport.

Thunderstorm Wind in KEARNEY, NEBRASKA
From 08-AUG-14 22:52:00 to 08-AUG-14 22:52:00 (CST-6)
Location: NEWARK
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Storm Chaser

A thunderstorm wind gust was estimated to be 60 mph.