The Bay Area can expect to see its greatest rainfall since April when showers pass through the region today and Thursday, according to the National Weather Service.

A storm system will pass over the region, causing precipitation in the North Bay today and spreading southward overnight, according to the weather service.

"The Bay Area should start to see some rain later this afternoon, but the bulk will be overnight and into the early morning hours," National Weather Service forecaster Steve Anderson said.

As much as a quarter-inch of rain could fall in parts of Marin County, such as Mt. Tamalpais, Kentfield and Muir Beach, and the Sonoma County mountains could see up to a half-inch of rain, Anderson said.

The weather service is warning that roads will likely be slick Thursday morning, creating hazardous driving conditions. Visibility may be reduced during heavier rain showers.

Additionally, the U.S. Coast Guard warns that strong southwesterly swells and rip currents are predicted in Marin and Santa Cruz counties over the next few days.

Boaters and swimmers should be cautious when out on the water. Swimmers caught in a rip current should swim parallel to the coast to escape the current before turning to shore, according to the Coast Guard.