SAN MATEO, Calif. -- Sand bags are now available for San Mateo County residents who live in flood-prone areas to pick up at numerous locations around the county.

The National Weather Service is warning that an especially potent storm is expected to move into the San Francisco Bay Area late Monday and continue through Wednesday morning.

Potential effects of the storm include mud and debris flows, flooding, downed power lines and hazardous driving conditions.

Redwood City residents can pick up sand bags at the Public Works Service building at 1400 Broadway St. There is a limit of 24 bags per household, according to the city.

Residents of unincorporated San Mateo County can pick up sand bags at the Grant Corp. yard, 752 Chestnut St., Redwood City; Princeton Corp. yard, 203 Cornell Ave., West Menlo Park; Pescadero Corp. yard, 1000 Pescadero Road, San Mateo; Pescadero High School, 350 Butano Cutoff Road, Pescadero; and La Honda Corp. yard, 59 Entrada Way, Woodside.

The storm stems from typhoon Melor, which hit Japan a few days ago. It is expected to begin in the North Bay Monday afternoon before spreading south on Monday night.

The Bay Area can expect 2 to 4 inches of rainfall and winds reaching 20 to 40 mph along the coast and in the hills. Gusts of 60 mph are possible in these areas, the NWS warned.

The rain and wind are expected to decrease on Wednesday as the storm system moves east.

Counties affected by the storm include San Francisco, San Mateo, Marin, Monterey, Contra Costa, Napa, Sonoma, Santa Clara and Alameda.

See A List Of Bay Area Sandbag Distribution Locations