Hail — Webster, Nebraska

2023-09-21 · near Red Cloud, Webster, Nebraska

Event narrative

Hail up to the size of baseballs fell across Red Cloud for approximately 25 minutes. There were numerous reports of car damage, and there was likely roof and siding damage as well. Trees in the area also suffered damage from the hail.

Wider weather episode

Between the mid-afternoon of Thursday the 21st and the early morning of Friday the 22nd, fairly widespread thunderstorm activity affected much of South Central Nebraska, but particularly counties between Interstate 80 and the Kansas border. Within this region, a few rounds of strong to severe storms unfolded, including a handful of intense supercells. Ground-truth severe weather reports were primarily highlighted by large hail, including localized instances of very large stones of baseball to softball size. While baseball size hail was reported in Red Cloud, the greatest concentration of very large hail reports ranging from baseball to over softball size (up to 4 inch diameter) occurred with a supercell between Lexington and Cozad, particularly the Darr area. With both hail storms there were reports of significant damage to vehicles, with photos from Dawson County depicting a car with several large holes punched through its back window. Elsewhere in the area, hail to at least golf ball size was reported in Cowles, between Axtell and Wilcox, and in Gilead. Fortunately, damaging winds were not a major issue, with the vast majority of measured and estimated gusts checking in under 58 MPH. The only reported exceptions were a measured 59 MPH gust near Minden (unofficial mesonet) and estimated speeds up to 60 MPH near Nora. Although radar-indicated rotation prompted three Tornado Warnings, fortunately no touchdowns were reported. In addition to the aforementioned severe weather, heavy rainfall and localized, mainly minor flooding also accompanied this event. Per dozens of observations from NWS/NeRAIN/CoCoRaHS observers, along with AHPS analysis, at least parts of the following counties picked up at least 2.50-3.50: Dawson, Gosper, Phelps, Buffalo, Kearney, Adams, Webster. Due in part to recent dryness, there were very few reports of impactful flooding. However, one exception transpired within the city of Kearney, where at least 3-4 fell...most of it in a short time between 9-11 p.m. CDT...prompting fairly extensive street flooding, including along 2nd Avenue.

Breaking down event evolution/timing and starting with the big picture in the mid-upper levels, forcing was on the weak side, with only subtle, low-amplitude disturbances drifting into the Central Plains from the west-southwest, well downstream from an expansive parent upper low churning away over the northwestern United States. Locally, things got underway between 3:30-5:30 p.m. CDT as a broken line of several strong to severe storms (including a few intense, slow-moving supercells) blossomed within a roughly 40-mile wide, northwest-southeast axis stretched from Dawson/Gosper counties in the west, to Nuckolls/Thayer counties in the east. This initial activity developed slightly north of a diffuse surface warm front draped near the Nebraska-Kansas border, in an environment characterized by temperatures in the upper 70s-low 80s (F) and dewpoints in the low-mid 60s. The mesoscale environment was primed for severe storms, featuring healthy mixed-layer CAPE of 2000-3000 J/kg, but somewhat modest deep-layer wind shear of only 30-35 knots (prompting slower storm motions). Between 5:30-6:30 p.m. CDT, most storms along the aforementioned axis weakened. However, an isolated supercell erupted during this time over Webster County just south of the earlier activity, pounding Red Cloud with large hail for roughly 25 minutes. Between 7-10 p.m. CDT, the primary action area within South Central Nebraska focused back to the west, as a few supercells roamed primarily Gosper, Furnas, Phelps and Harlan counties. Then, between 10 p.m. and 1 a.m. CDT, these western storms congealed into a fairly compact, north-south oriented mesoscale convective system (MCS) that rolled eastward through the southern-most two rows of South Central Nebraska counties, aided by the development of a 30-40 knot low level jet. Fortunately, this activity was largely sub-severe, but did produce a few 58+ MPH wind gusts along with torrential rain. Shortly after 1 a.m. CDT, this MCS departed the local area out of Fillmore/Thayer counties...ending the severe weather threat for the night. In its wake, a large shield of trailing stratiform rain with a few embedded, weak thunderstorms continued within South Central Nebraska for several more hours before vacating far eastern counties by 6 a.m. CDT on the 22nd.

View location on OpenStreetMap → (40.0900, -98.5200)

Source: NOAA Storm Events Database, event_id 1137141. Narrative written by the NWS forecast office that issued the report.