Thunderstorm Wind — Sherman, Nebraska

2022-06-07 · near Litchfield, Sherman, Nebraska

Event narrative

Wind gusts were estimated to be near 70 MPH. These gusts were accompanied by hail as large as 3.5 inches in diameter. Several reports of shattered windows and damaged siding were received from this wind-driven hail. Vehicle damage was reported, including from the Emergency Manager who experienced that largest hail and strongest wind on Highway 10 east of Hazard.

Wider weather episode

While nearly all of South Central Nebraska experienced thunderstorms on this Tuesday evening, the majority of severe storms (significantly severe in places) concentrated within two distinct, northwest-southeast swaths mainly no more than 10-20 miles across...both associated with discrete supercells (one of which eventually morphed into more of a quasi-linear convective system/QLCS). The primary/longest corridor of severe weather primarily impacted the the following local counties: southern/western Sherman, northern/eastern Buffalo, southern/western Hall, northern/eastern Adams (including Hastings), southern/western Clay and much of Nuckolls/Thayer. The other notable (but shorter-in-length) swath of storm damage wrought havoc across parts of eastern Hamilton, southern/western York and northern Fillmore counties. Within each of these corridors, there were numerous reports of severe winds and/or large hail (some at least 2-3 inch diameter), causing countless instances of damage such as: broken windows in homes and vehicles, significant damage to siding/roofs, innumerable flipped irrigation pivots, and the destruction of many thousands of acres of young crops. In addition to the considerable hail/damaging winds that impacted several counties, one QLCS tornado was also confirmed in Nuckolls/Thayer counties (rated EF-0). This event marked the fourth-consecutive day of severe storms within the 24-county area, and was the overall most significant round of all. Duration-wise, this event was actually fairly quick-hitting, with all South Central Nebraska severe storms unfolding during a 3.5 hour span between 7:00-10:30 p.m. CDT...starting off in northern counties and eventually exiting far south-southeast counties.

Digging deeper into storm reports, and starting with the QLCS EF-0 tornado, it was determined to have tracked for nearly 10 miles through southeastern Nuckolls/southwestern Thayer counties shortly before 10 p.m. CDT, causing tree damage in Ruskin and then destroying/damaging several grain bins, irrigation pivots and a few outbuildings before lifting north of Byron. However, by far the biggest impacts of the evening resulted from large hail/damaging winds. Within the aforementioned longer corridor of damage extending along a line from Sherman through Nuckolls/Thayer counties, a sampling of some of the more noteworthy reports included: 2.5-3.5 diameter hail and 70 MPH winds in the Litchfield and Hazard areas (considerable window/siding damage); hail stones 2-4 diameter through the Ravenna/Pleasanton areas (considerable window/siding damage including shattered windows on a few fire trucks); combo of hail 1.75-2.50 diameter and measured 66 MPH winds in Hastings (considerable window/siding damage especially on north/west sides of the city); widespread 60-70 MPH winds through southern/western Clay County with over a dozen toppled irrigation pivots; wood frame outbuilding destroyed and a semi truck overturned near Hebron. Within the shorter swath of concentrated damage that tore through Hamilton/York/Fillmore counties, various reports included: a semi truck blown over on Interstate 80 and areas of complete crop destruction and many overturned irrigation pivots due to a combo of 60-70 MPH winds and hail up to 2 diameter (particularly in the Hampton, Henderson and McCool Junction areas). While these two main swaths accounted for the vast majority of South Central Nebraska storm reports during the evening, there were also a few more isolated pockets of severe weather well-removed from both of them. These included a mesonet-measured 64 MPH wind gust near Lexington and also a handful of reports associated with a supercell that barely skirted the northeast fringes of the local area (including golf ball size hail near Genoa and a measured 65 MPH gust near Shelby (with pivots reported overturned).

Examining event evolution/timing, the first scattered storms of the evening (initially non-severe) formed between 6-7 p.m. CDT along a west-east oriented band across far northern local counties. Then, the action really ramped up/intensified during the next hour as: 1) a long-lived supercell that developed several hours prior in the northern NE Panhandle entered the local area into Sherman County (the beginning stages of the primary swath of severe weather)...2) a new intense supercell flared up over central/eastern Hamilton County (along the southern fringes of the initial weak northern activity)...3) another comparably shorter-lived supercell developed out of the eastern fringes of the northern storms and clipped the northeast fringes of the local area in Nance/Merrick/Polk counties. Between 8-10 p.m. CDT, the two primary South Central Nebraska supercells continued east-southeast, with the eastern one exiting the local area out of York/Fillmore counties, while the western one gradually merged with a developing convective line that extended off to its west-southwest. Shortly after this powerful storm tore through eastern Adams/western Clay counties, a gradual storm mode transition from semi-discrete supercell to small-scale severe QLCS was complete, leading to a reduced large hail threat but a continued threat of damaging winds (along with the aforementioned tornado). Finally, between 10-11 p.m. CDT the main QLCS segment over Thayer County, along with weaker linear storms trailing westward along the Nebraska-Kansas border, completely exited South Central Nebraska to the south-southeast, ending a very active 3-4 hours. Wrapping up with a closer look at the meteorological setup, this event was the grand finale to a multiple-day stretch of at least spotty severe storms within South Central Nebraska. But compared to prior days, forcing was stronger both aloft and at the surface, leading to an overall-more impactful event. In the mid-upper levels, west-northwest flow prevailed, featuring a fairly potent (albeit low amplitude) shortwave trough zipping eastward across northern NE/southern SD during the afternoon-evening. At the surface, the day began with an initially weakly-defined, west-east oriented front draped across southern portions of the local area. But during the evening, this boundary sharpened up and made a more pronounced southward surge into Kansas in response to a combination of pressure rises driven by the aforementioned upper wave and also convective outflow. Although quite a bit of daytime cloud cover helped hold afternoon temperatures across most of South Central Nebraska down in the mid-upper 70s (F) and low level moisture levels were only only seasonably-modest (dewpoints low-mid 60s F), an impressive combination of strong deep layer wind shear of at least 50-60 knots and mixed-layer CAPE of 1000-2000 J/kg clearly supported higher-end severe weather. From a forecast/messaging perspective this was a well-anticipated event, as SPC's second Day 2 Outlook (issued on the 6th) upgraded most of South Central Nebraska to an Enhanced Risk (level 3 of 5), with this Enhanced category then maintained throughout the subsequent Day 1 cycle.

View location on OpenStreetMap → (41.1800, -99.2000)

Source: NOAA Storm Events Database, event_id 1033027. Narrative written by the NWS forecast office that issued the report.