A tornado-producing storm tore through southwestern Oklahoma early Monday, with at least one confirmed tornado, the National Weather Service said.

The storm occurred near Granite, a city of about 1,600 residents, about 3:37 a.m. CST, the agency said.

Tornado warnings were in effect for western Washita County, southwestern Custer County, northwestern Kiowa County, northeastern Greer County and southeastern Beckham County.

This is a development story. Check back later for updates.