A tornado warning was issued Thursday evening for parts of California as an unusually volatile spring storm moved through the Central Valley, bringing the threat of damaging winds, hail and a possible tornado.

Forecasters said “a severe thunderstorm capable of producing a tornado” was located near South Dos Palos, and moving northeast at 15 mph.

The storm was expected to mainly affect rural parts of southwestern Madera and western Fresno counties.

The weather service said the warning would remain in effect until 6:45 p.m

In a separate severe thunderstorm warning, the agency said the same system was capable of producing 70 mph wind gusts and quarter-size hail.

“Flying debris will be dangerous to those caught without shelter,” the weather service said in its warning. “Damage to roofs, windows and vehicles will occur. Tree damage is likely.”

The warning was based on radar-indicated rotation, meaning forecasters detected wind patterns that can signal a tornado may develop. That does not necessarily mean a tornado has or will touch down. A tornado is considered confirmed only when it reaches the ground.

The warning came as a broader storm system began creating conditions more favorable for thunderstorms across California.

Such storms are relatively uncommon in much of the state, but meteorologists have warned that this pattern could produce lightning, hail, strong wind gusts and isolated funnel clouds or tornadoes through the weekend.

Residents in the tornado warning area were urged to take shelter immediately.

The weather service advised people to move to a basement, if available, or to an interior room on the lowest floor of a sturdy building and to stay away from windows. People outdoors, in vehicles or in mobile homes were told to get to substantial shelter and protect themselves from flying debris.

Forecasters also warned that heavy rain could lead to localized flash flooding. Drivers were urged not to travel through flooded roadways.

Officials said residents should continue monitoring alerts from the National Weather Service, local media and emergency notifications as conditions change.

Residents can receive weather notifications in multiple ways:

This article originally published at Tornado warning issued in Central California as severe storm hits.