The National Weather Service in Tulsa released its initial report on the April 26, 2016, tornado event in eastern Oklahoma and northwest Arkansas.
Tornadoes with a preliminary rating of EF-1 broke out in Tulsa, Bixby, Broken Arrow, Checotah, Twin Oaks and Decatur, Oklahoma. EF-0 were measured in Nowata and Craig Counties.
EF-1 tornadoes are marked by 86 to 110 m.p.h. winds and are considered weak tornadoes.
"This line of thunderstorms...produced wind gusts of 60 to near 90 mph due to the ample instability and deep layer sheer in place across the region and an upper-level low approaching the area," the report states.
"Brief tornadoes along the leading edge of the QLCS caused damage throughout eastern Oklahoma and northwest Arkansas."
The report also mentions that the Oklahoma Mesonet site in Copan measure a wind gust of 87 mph and the Hugo site 65 mph.
The NWS asks if residents to submit video and photos to their Facebook page, listing where the photo or video was taken and who took it.