LOS ANGELES -

President Barack Obama is telling California's governor that the federal government will do what's necessary to help with a historic drought afflicting the state.

Obama called Gov. Jerry Brown on Wednesday for an update on the drought. California is in its third dry year and 17 communities are in danger of running out of water within four months.

Brown will meet with regional water district heads in Los Angeles today to discuss the emergency and call on all californians to conserve water.

Gov. Jerry Brown formally proclaimed a drought in California, a move that codified what farmers and ranchers in the state had known for weeks. The U.S. Drought Monitor says "extreme drought" exists in central and northern California, where much of the state's ranching is located.

Many California ranchers are selling off parts of their herds as normally green pastures have turned brown.

The White House says Obama told Brown Wednesday the federal government will keep working to support California's response to the drought. Obama told the governor he was concerned about the impact of the drought on California's citizens, economy and environment.

The White House says the National Drought Resilience Partnership is coordinating the federal response. The Federal Emergency Management Agency and the Agriculture Department are involved in the effort.

The National Oceanic and Atmospheric Administration's website is predicting a tenth of an inch of rain will fall in San Francisco over the next two days and more than 2 inches in parts of Sacramento. 

The wet weather is not expected to ease the drought that has gripped the region for months. 

National Weather Service forecaster Diana Henderson says the Bay Area has had only about 10 to 20 percent of the rain it usually gets by this time of year.