EF1 Tornado — Sequoyah, Oklahoma

2018-11-30 · near Blackgum, Sequoyah, Oklahoma

Event narrative

This is the first segment of a six segment tornado. This long-track tornado developed near Blackgum where homes were damaged, barns and outbuildings were destroyed, and trees were snapped. The tornado moved north-northeast, snapping and uprooting numerous trees as it approached an inlet of Lake Tenkiller, and crossed into Cherokee County. Based on this damage, maximum estimated wind in this segment of the tornado was 100 to 110 mph.

Wider weather episode

A strong low pressure trough translated from the southwestern United States into the Southern Plains on November 30th and December 1st. Warm and moist air had spread northward into eastern Oklahoma ahead of this system. Atmospheric instability became moderately strong during the afternoon and evening hours to the east of a cold front that was over western Oklahoma and south of a stationary front that was located across northern Oklahoma into southern Missouri. As the strong storm system moved into the Southern Plains on the 30th, wind fields throughout the atmosphere increased substantially, which resulted in very strong deep-layer and low-level wind shear across eastern Oklahoma during the evening and overnight hours.

Thunderstorms developed during the evening hours of the 30th across central and eastern Oklahoma. Moderately strong atmospheric instability across the area combined with very strong wind shear to produce organized severe thunderstorms, including supercells. Supercell thunderstorms produced several tornadoes and damaging thunderstorm wind gusts across eastern Oklahoma. One of the tornadoes was strong and exceptionally long-tracked, affecting Sequoyah, Cherokee, Adair, and Delaware Counties. A squall line moved rapidly across the area ahead of the surging cold front and produced additional tornadoes and damaging wind gusts.

View location on OpenStreetMap → (35.6064, -94.9933)

Source: NOAA Storm Events Database, event_id 791687. Narrative written by the NWS forecast office that issued the report.