EF4 Tornado — Mcclain, Oklahoma

2011-05-24 · near Blanchard, Mcclain, Oklahoma

Event narrative

This tornado is labeled C1 (Segment #2 of the Chickasha-Blanchard-Newcastle tornado). Significant damage continued as the violent tornado moved over the McClain county border. This may have been the strongest portion of this tornado, with wind speeds near 200 mph. Well-built homes were destroyed, with some cleaned off of their foundation. A concrete dome home was severely damage, mainly by the flying debris. Trees were debarked or destroyed. Very little was left standing for the first few miles into McClain county. Fairly consistent EF-3, with brief periods of EF-4 damage occurred as the tornado neared/crossed Highway 9, near the Highway 76 junction. The tornado began to weaken as it moved toward the Cleveland county border, with mainly trees and power poles/lines snapped. The tornado continued into Cleveland County. Monetary damage estimates were not available.

Wider weather episode

A tornado outbreak occurred over parts of northern and central Oklahoma during the day on the 24th, with violent tornadoes devastating several communities. By the end of the day, one EF-5, two EF-4, and two EF-3 tornadoes destroyed buildings, ripped up trees and power poles, and unfortunately, resulted in 11 deaths. The day began with a strong upper level trough ejecting out of the southwest United States. The trough took on a negative tilt as it approached the southern Plains. A strong jet stream was located at both the middle and upper levels rotating around the upper trough. At the surface, a low pressure strengthened rapidly over northwest Oklahoma, keeping the low-level flow of warm, moist air to flow east of a dry line that had moved into western Oklahoma. Thunderstorms developed by early afternoon over western Oklahoma, and quickly became supercellular as they moved northeast. Strong low-level rotation developed early, with the first tornado occurring over Blaine county, and moved northeast into Major county. Another supercell rapidly gained low-level rotation as it moved from Caddo into Canadian County. This tornado became the strongest of them all as it moved north of El Reno, west of Piedmont, and to south of Guthrie in Logan county. Nine people died as a result of this tornado. Two more powerful supercells developed over Grady county, and they moved northeast into McClain and Cleveland counties. Finally, the final tornado occurred east of Norman into Pottawatomie county. The timing of this outbreak could not have come at a worse time, as rush hour was just unfolding as the tornadoes neared the Oklahoma City metro area.

View location on OpenStreetMap → (35.1890, -97.6700)

Source: NOAA Storm Events Database, event_id 315859. Narrative written by the NWS forecast office that issued the report.