Hail in Adams County, Nebraska

Half dollar to golf ball size hail was reported.

Severe storms produced numerous reports of hail and 3 brief, weak tornadoes on this Tuesday afternoon and evening. Between 230 and 330 PM CST, scattered fairly small supercell thunderstorms developed along a line from Red Cloud to Grand Island to Columbus. They were not mini-supercells, though, as cloud tops were near 40,000 ft. The storms generally remained along that line except for one storm that moved east into Clay County and another small multicell cluster that moved east along the Nebraska-Kansas border. Nearly 30 occurrences of severe hail were reported with most of between the sizes of quarters and golf balls. The largest hail reported was 2 inches in diameter in the town of Roseland. Three brief EF-0 tornadoes also occurred. The storms from Grand Island to Columbus formed along a slow-moving cold front. One tornado was associated with a supercell located on or very close to the front just west of Aurora. Another tornado formed near Doniphan as a north-northeastward-moving storm crossed the front. The third tornado occurred with the storm that moved east along the Nebraska-Kansas border. This storm evolved from a small bow echo and exhibited a spiral shape as it produced a brief tornado near Chester. The storms dissipated or moved out of south central Nebraska by 6 PM CST.

A low pressure system was near Lake Superior with a slow-moving cold front extending southwest across Nebraska to the Oklahoma Panhandle. In the upper-levels, southwest flow covered most of the U.S., with a trough over the West and a ridge over the Northeast. Just prior to thunderstorm development, temperatures were in the lower 80s with dewpoints in the upper 50s to near 60. With mid-level lapse rates near 8 C/km, MLCAPE was 2000-2500 J/kg. Deep layer shear was 40-50 kts, which was more than sufficient for supercell convective mode.