mountain snow
Rain is changing to snow at higher elevations Sunday. Photo via @NWSSanDiego Twitter

A winter storm was predicted to bring a band of heavy rain and mountain snow to San Diego County through Sunday afternoon as a cold front moves southeast across the region, the National Weather Service said.

After a brief break late Sunday afternoon and evening, scattered showers and isolated thunderstorms were expected to move across the area later Sunday and Monday.

A wind advisory was issued by the NWS until 6 p.m. Sunday for San Diego County coastal areas and valleys, and a winter storm warning was issued from 6 p.m. Sunday to 10 p.m. Monday for the San Diego County mountains.

A small craft advisory was issued until 4 p.m. Monday for coastal waters from San Mateo Point to the Mexican Border and out to 30 nautical miles of waters from San Mateo Point to the Mexican border extending 30 to 60 nautical miles out including San Clemente Island.

Most temperatures Sunday were in the 50s, with overnight lows in the 40s. The mountains were expected to be in the mid-40s, dropping into the mid-30s overnight, and highs in the deserts were forecast in the mid-60s with lows in the mid-40s.

Snow levels will fall through Sunday night, bottoming out around 3,500 feet Monday. Driving in these areas was expected to be treacherous due to low visibility in fog, snow, and blowing snow, the NWS said.

Tuesday and Wednesday were expected to be dry and cold followed by minor warming Thursday and Friday.

There was a chance for additional precipitation next weekend.

Gusty south winds 25-30 knots Sunday morning were expected to turn to the northwest Sunday afternoon. Rough seas, strong winds and heavy rain leading to reduced visibility may occur through much of Sunday and Monday. A slight chance of thunderstorms was expected over the coastal waters starting later Sunday night into Monday morning. Conditions were predicted to improve on Tuesday.

A longer-period swell of 7-10 feet at 12-14 second periods could arrive at the beaches after midnight Sunday. This may lead to some wave sets of up to 6-7 feet on some of the west-facing beaches on Monday and Tuesday, as well as enhanced risks for rip currents.

City News Service contributed to this article.