Isolated to scattered severe thunderstorms raked across portions of South Central Nebraska on this Sunday afternoon, resulting in not only several reports of large hail and damaging winds, but also Nebraska's first three tornadoes of 2014. Fortunately, these tornadoes were of the weak and brief variety (rated EF-0) and resulted in no reports of damage. The first tornado touched down shortly before 230 PM CDT in far northern Franklin County near Upland. The other two tornadoes occurred a few hours later between 430-530 PM, associated with the strongest, most organized supercell storm of the day as it tracked north through the far eastern counties of the local area. One of these tornadoes touched down north of Bradshaw in York County and the other in west-central Polk County several miles west-northwest of Osceola. As for hail reports, the majority of them originated from western Thayer and Fillmore and northern Adams counties, including some stones up to golf ball size. There were only a few reports of marginally severe winds, highlighted by a measured 62 MPH gust near Wood River.
All strong to severe thunderstorms within the 24-county area occurred between 12-6 PM CDT in association with a seasonably classic and powerful, vertically-stacked low pressure system migrating northeastward into South Central Nebraska. All severe storms also concentrated east and northeast of a Lexington-Franklin line, as the far southwestern counties were spared due to the passage of a well-defined, northward-drifting surface dryline and occluding cold front. There were essentially two primary areas and modes of severe storm development. The first, which accounted for most of the day's thunderstorm activity, consisted of a broken arc of storms lifting north across mainly central and west-central portions of the area. Several individual cells within this arc drifted northwestward in sync with the counter-clockwise circulation of the parent low. The initial development got going over Dawson County between 12-1 PM CDT, but these storms yielded no reports of severe weather before departing the local area into Custer and Lincoln counties. Following a brief lull, the second and more dominant arc of convection flared up generally along an axis running from eastern Dawson to Webster counties between 130 PM and 3 PM CDT, during which time the first tornado occurred near Upland. Eventually, the eastern-most cells in the arc became the most intense as they lifted north-northwest, resulting in several hail reports along a path through counties including Adams, Hall and Sherman between 330 PM and 5 PM CDT before weakening and eventually departing the local area to the north. Meanwhile, the second primary area/mode of severe weather developed farther east, and revolved around an isolated supercell that developed over southwestern Thayer County around 230 PM CDT and then drifted almost due north for the next several hours, finally departing the local area out of far eastern Nance and Merrick counties around 6 PM CDT. This lone supercell produced both the York and Polk County tornadoes, along with several hail reports. Just to the east of this main supercell of the day, another briefly-severe storm affected far eastern York County around 5 PM CDT.  All strong-severe convection vacated the entire 24-county area by around 6 PM CDT, leaving behind only lingering stratiform rain in western counties under the core of the mid level low.
On the synoptic scale, the day began with a deep, vertically stacked closed low centered over central portions of the Kansas-Colorado border area as its 984 millibar surface low started to occlude. By early afternoon, severe storm development in South Central Nebraska focused within a corridor of steep low level lapse rates under the mid-level dry slot, with the southwestern extent of storm development defined by the leading edge of the northward-drifting occluded front/dryline. By late afternoon, the deep low had migrated to near McCook, allowing the surface front to push northward through all of South Central and ending the severe threat. Ahead of this occluded front/sharp dryline, surface-based CAPE climbed to around 1000 J/kg in an environment featuring surface dewpoints in the mid-upper 50s F. Behind the boundary, dewpoints quickly crashed into the 30s F.

Thunderstorm Wind in YORK, NEBRASKA
From 27-APR-14 15:59:00 to 27-APR-14 15:59:00 (CST-6)
Location: WACO
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Heavy pea size hail occurred along with estimated 60 mph winds occurred at mile marker 359 on Interstate 80.

Hail in THAYER, NEBRASKA
From 27-APR-14 13:50:00 to 27-APR-14 13:50:00 (CST-6)
Location: CARLETON
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Hail in FILLMORE, NEBRASKA
From 27-APR-14 14:15:00 to 27-APR-14 14:15:00 (CST-6)
Location: SHICKLEY
Magnitude: 1.75 
Property damage: 25.00K
Crop damage: 0.00K
Reported by: State Official

Hail in FILLMORE, NEBRASKA
From 27-APR-14 14:15:00 to 27-APR-14 14:15:00 (CST-6)
Location: SHICKLEY
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

This report was received via Twitter.

Hail in ADAMS, NEBRASKA
From 27-APR-14 14:44:00 to 27-APR-14 14:44:00 (CST-6)
Location: (HSI)HASTINGS ARPT
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: NWS Employee

Quarter size hail occurred at Adams Central High School.

Hail in ADAMS, NEBRASKA
From 27-APR-14 14:47:00 to 27-APR-14 14:47:00 (CST-6)
Location: (HSI)HASTINGS ARPT
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Storm Chaser

Quarter size hail was ongoing at the time of the report.

Hail in HALL, NEBRASKA
From 27-APR-14 15:04:00 to 27-APR-14 15:04:00 (CST-6)
Location: ALDA
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Storm Chaser

Quarter to walnut size hail occurred near the Interstate 80 exit for Alda. This report, along with a photo, was received via Twitter.

Hail in YORK, NEBRASKA
From 27-APR-14 15:19:00 to 27-APR-14 15:19:00 (CST-6)
Location: BRADSHAW
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Thunderstorm Wind in HALL, NEBRASKA
From 27-APR-14 15:23:00 to 27-APR-14 15:23:00 (CST-6)
Location: CAIRO
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A 60 mph wind gust occurred with a severe thunderstorm.

Thunderstorm Wind in HALL, NEBRASKA
From 27-APR-14 15:15:00 to 27-APR-14 15:15:00 (CST-6)
Location: WOOD RIVER
Magnitude: 54.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

A 62 mph wind gust occurred from a severe thunderstorm.

Hail in SHERMAN, NEBRASKA
From 27-APR-14 15:45:00 to 27-APR-14 15:45:00 (CST-6)
Location: SHERMAN RES
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

This report was received by a spotter near the Sherman and Valley County lines.

Hail in ADAMS, NEBRASKA
From 27-APR-14 14:52:00 to 27-APR-14 14:52:00 (CST-6)
Location: (HSI)HASTINGS ARPT
Magnitude: 1.75 
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in FILLMORE, NEBRASKA
From 27-APR-14 14:54:00 to 27-APR-14 14:54:00 (CST-6)
Location: GRAFTON
Magnitude: 1.75 
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Storm Chaser

The report, along with a photo, was received via Twitter.

Tornado in POLK, NEBRASKA
From 27-APR-14 16:17:00 to 27-APR-14 16:18:00 (CST-6)
Location: SWEDEHOME
Tornado F-scale: EF0
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Storm Chaser

This tornado, which touched down northwest of the intersection of Highways 92 and 39 approximately 8 miles west-northwest of Osceola, was witnessed by multiple storm chasers.  No damage was reported with this tornado.

Tornado in YORK, NEBRASKA
From 27-APR-14 15:40:00 to 27-APR-14 15:41:00 (CST-6)
Location: BRADSHAW
Tornado F-scale: EF0
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Storm Chaser

This tornado, which briefly touched down approximately 5 miles north-northeast of Bradshaw, was witnessed by storm chasers.  No damage was reported with this tornado.

Tornado in FRANKLIN, NEBRASKA
From 27-APR-14 13:26:00 to 27-APR-14 13:29:00 (CST-6)
Location: UPLAND
Tornado F-scale: EF0
Property damage: 0.00K
Crop damage: 0.00K
Reported by: NWS Employee

This tornado touched down approximately 2 miles north-northeast of Upland and was on the ground for about 3 minutes. No damage was reported with this tornado.

Hail in FRANKLIN, NEBRASKA
From 27-APR-14 12:57:00 to 27-APR-14 12:57:00 (CST-6)
Location: FRANKLIN
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in BUFFALO, NEBRASKA
From 27-APR-14 13:15:00 to 27-APR-14 13:15:00 (CST-6)
Location: ELM CREEK
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in THAYER, NEBRASKA
From 27-APR-14 13:25:00 to 27-APR-14 13:25:00 (CST-6)
Location: BYRON
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

This is a delayed report for quarter size hail that occurred in the community of Byron.  This report was received via Facebook.

Hail in ADAMS, NEBRASKA
From 27-APR-14 14:57:00 to 27-APR-14 14:57:00 (CST-6)
Location: (HSI)HASTINGS ARPT
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager