Rain and snow are possible early this week after clouds that will build throughout Monday moved into Southern California overnight.
Sprinkles were reported early Monday in some parts of Southern California, but most of the rain is expected to begin around the height of the afternoon commute.
"After lunch-time, we start to see overcast skies really cloud-up," said NBC4 forecaster Crystal Egger. "Five to 9 o'clock is when the bulk of the rain hits.
"The drive home is going to be a completely different story than the drive to work."
Light rain was reported early Monday in the South Bay and some mountain communities east of Los Angeles.
The storm will move out late Monday after possibly bringing about a quarter-inch to half-inch of rain. The most significant rainfall totals are expected in the Santa Gabriel and Santa Monica mountain ranges.
Winter weather advisories are in effect for Riverside and San Bernardino counties.
Southern California has been well below its rainfall average for January. Most of the drought-stricken state, except for a portion of northwestern California, has been dry during what is historically one of its wettest months of the year.