For about three hours on this Thursday afternoon, the southeastern quadrant of South Central Nebraska saw a flare-up of eastward-tracking, strong-to-severe thunderstorms, yielding fairly localized swaths of large hail up to golf ball size and wind gusts estimated up to around 70 MPH. All hail reports were actually associated with the first severe storm of the day, an initially-isolated cell that rumbled along the borders between Adams/Hall and Clay/Hamilton counties mainly 4-5 p.m. CDT, dropping stones up to golf ball size in Hansen and Trumbull. During nearly that same time frame, a separate severe-warned storm (unverified) blossomed about 25 miles to the south, advancing from northern Webster into southern Clay County. By 5 p.m. CDT these two storms had merged into a small-scale complex over eastern Clay County, signaling a transition to more of a damaging wind threat as it marched across Fillmore County over the next hour. Along the way, tree damage was reported near Milligan and Exeter, and estimated 70 MPH gusts overturned irrigation pivots near Grafton. By 6:30 p.m. this convection departed Fillmore County to the east, ending this relatively brief/localized round of severe storms within South Central Nebraska.
As for the meteorological background, the local area resided under quasi-zonal flow in the mid-upper levels, well-downstream from an upper low just off the California coast that was ejecting various low-amplitude disturbances east-northeastward into the Central Plains. One of these upper waves arrived on scene into central Nebraska by mid-afternoon, likely sparking rapid convective initiation despite quite a bit of afternoon cloud cover and resultant questions about the degree of available instability. At the surface, these storms initiated slightly to the north-northwest (cool side) of a quasi-stationary front extending northeastward from a weak-but-evident low pressure center over central KS (around 1004 millibars at 21Z). Despite the aforementioned mostly cloudy skies over South Central Nebraska holding afternoon temperatures down in the upper 70-low 80s (F) most places, the combination of plentiful low-level moisture (dewpoints upper 60s/around 70), weak convergence along the surface frontal zone and favorable timing of the incoming mid-level wave proved sufficient for severe storm development. Mid-afternoon mesoscale parameters in the area of concern featured a decent combination of up to 2000 J/kg mixed-layer CAPE and 40 knots of deep-layer wind shear.

Hail in ADAMS, NEBRASKA
From 24-JUN-21 15:00:00 to 24-JUN-21 15:00:00 (CST-6)
Location: PROSSER
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Thunderstorm Wind in CLAY, NEBRASKA
From 24-JUN-21 16:00:00 to 24-JUN-21 16:00:00 (CST-6)
Location: EDGAR
Magnitude: 50.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

A wind gust of 58 MPH was measured by a mesonet station located 2 miles east of Edgar.

Hail in ADAMS, NEBRASKA
From 24-JUN-21 15:15:00 to 24-JUN-21 15:20:00 (CST-6)
Location: (HSI)HASTINGS ARPT
Magnitude: 1.75 
Property damage: 100.00K
Crop damage: 0.00K
Reported by: Social Media

Hail ranging from quarter to golf ball size was reported in the Hansen area.

Hail in CLAY, NEBRASKA
From 24-JUN-21 15:20:00 to 24-JUN-21 15:30:00 (CST-6)
Location: TRUMBULL
Magnitude: 1.75 
Property damage: 100.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Thunderstorm Wind in CLAY, NEBRASKA
From 24-JUN-21 15:26:00 to 24-JUN-21 15:26:00 (CST-6)
Location: TRUMBULL
Magnitude: 52.00 EG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Wind gusts estimated to be near 60 MPH resulted in minor tree damage in town.

Thunderstorm Wind in FILLMORE, NEBRASKA
From 24-JUN-21 16:12:00 to 24-JUN-21 16:12:00 (CST-6)
Location: GRAFTON
Magnitude: 61.00 EG
Property damage: 180.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Wind gusts estimated to be near 70 MPH knocked three irrigation pivots over near Road H between Roads 5 and 6.

Thunderstorm Wind in FILLMORE, NEBRASKA
From 24-JUN-21 16:40:00 to 24-JUN-21 16:40:00 (CST-6)
Location: MILLIGAN
Magnitude: 52.00 EG
Property damage: 2.00K
Crop damage: 0.00K
Reported by: County Official

Wind gusts estimated to be near 60 MPH resulted in minor tree damage near Road P and Road 23.

Thunderstorm Wind in FILLMORE, NEBRASKA
From 24-JUN-21 16:43:00 to 24-JUN-21 16:43:00 (CST-6)
Location: EXETER
Magnitude: 52.00 EG
Property damage: 2.00K
Crop damage: 0.00K
Reported by: County Official

Wind gusts estimated to be near 60 MPH resulted in tree damage in the area. Some limbs were down on Highway 6 between Roads 18 and 19.