Forecasters predict as much as three and a half inches of rain could fall in the San Bernardino Mountains.
Elizabeth Adams, who’s a meteorologist at the National Weather Service, expects the rain to begin this morning and continue through Wednesday morning.
She says this week’s rainfall will be warmer than last weekend’s and the threat level for flooding is high.
“When a warm rain actually falls on that snowpack, it could lead to greater melting at a more rapid rate,” said Adams.
San Bernardino County Public Works officials say they’ve opened drainage culverts so the rainwater has a place to go.
They say residents should protect their homes with sandbags, which are available for free at several county fire stations.