The EF-4 tornado that killed at least one person and caused extensive damage in Barnsdall and Bartlesville on May 6th was on the ground for 39 miles, according to the National Weather Service in Tulsa.

After surveying the damage, forecasters said the tornado developed southeast of Hominy in Osage County. There, NWS-Tulsa said the tornado uprooted and snapped trees and broke several metal power poles.

Forecasters said more trees were damaged between Hominy and Barnsdall.

In Barnsdall, forecasters said the tornado caused severe damage to the wax plant on the southeast side of town and severely damaged or destroyed many homes on the east side of Barnsdall.

Watch the tornado track on radar here

NWS-Tulsa said the type of damage found on homes and metal structures suggested wind speeds from 150 to 165 mph. One home had damage that the surveyors said suggested wind speeds of 165 to 175 mph, which puts it in the EF-4 category.

Forecasters said trees were snapped or uprooted and more homes and outbuildings were damaged between Barnsdall and Bartlesville.

NWS-Tulsa said the tornado moved into Bartlesville in Washington County and damaged trees, homes and businesses.

They said the tornado eventually merged with another storm and ended on the northeast side of Bartlesville.

Read more about this and other recent tornadoes here