LOS ANGELES (AP) — Thousands of people are under evacuation orders as a powerful Pacific storm approaches California.

The National Weather Service says an atmospheric river — a huge plume of subtropical moisture — is aimed at the state's central and southern coast, where wildfire scars have left foothill communities vulnerable to flooding and debris flows.

The storm is expected to arrive late Tuesday and persist through Thursday, bringing 2-5 inches (5-13 centimeters) of rain to coastal areas and valleys, and 5-10 inches (13-25 centimeters) in foothills and mountains.

As many as 30,000 people have been ordered to leave communities by noon on the south coast of Santa Barbara County, where a Jan. 9 deluge unleashed deadly debris flows into Montecito.

Neighboring Ventura County has taken similar measures amid concerns in adjacent counties.