The light rain the moistened parts of San Diego County overnight, was expected to become heavier and more widespread throughout the day. Precipitation amounts are expected to range from a third to half an inch near the coast to 1.5 inches in the mountains, forecasters said.
Forecasters predict .36 inches of rain in San Diego, .43 inches in Oceanside, .47 inches in Escondido, .56 inches in Ramona, .57 inches in Alpine, .83 inches at Mt. Laguna, .92 inches in Julian and 1.26 inches on Palomar Mountain by late Wednesday morning.
The Los Angeles area was receiving the brunt of the storm. Unusually heavy rain jammed the morning commute and caused scattered flooding.
Downtown Los Angeles received 1.70 inches of rain before 7:30 a.m., making Tuesday the wettest day of 2015, and more precipitation was expected, according to the National Weather Service.
The rain will do little to ease the region's drought, the Los Angeles Times reported. Up to 90 percent of the rain that falls on urban areas of Southern California flows into storm drains and eventually ends up in the ocean, the paper said.