SACRAMENTO, Calif. (Reuters) – Several months of wet weather have dramatically eased California’s years-long drought, replenishing reservoirs and parched aquifers and forcing state water officials to switch – at least temporarily – from managing shortages to avoiding floods.

With rain continuing to fall following a deluge that brought 20 inches (50 cm) of precipitation to some areas this week, the snowpack in the Sierra Nevada mountains – crucial for storing water needed in the state’s long, hot summers – is deeper and wetter than normal. Reservoirs were well above normal levels, state and federal drought experts said on Thursday.

“This is the wet winter that makes us cautiously optimistic,” Ted Thomas, a spokesman for the California Department of Water Resources, said on Thursday. “Conditions are improving.”

California has been in the grip of drought for five years, leading farmers to fallow a half-million acres 500,000 acres (200,0000 hectares) of cropland, and forcing some residents to rely on bottled water for drinking.

But the storms that have swept through the state since early autumn have released as much as 42 percent of the state from drought conditions, the U.S. Drought Monitor report said on Thursday, down from less than 3 percent a year ago.

Just 2 percent of the state was experiencing what scientists call “exceptional” drought, the worst category, down from 40 percent two years ago, said the report by the National Drought Mitigation Center.

So much water was coursing through California’s waterways this week that the state’s climatologist, Michael Anderson,

said he was too busy trying to help with flood control operations to talk about the drought on Thursday.

Engineers opened floodgates along the Sacramento River system, drenching low-lying land and sending water coursing into the Sacramento-San Joaquin River Delta in part to protect the state capital, Sacramento, said Dave Rizzardo, an expert with the state Department of Water Resources.

A high tide from the Pacific Ocean was expected to swell the delta, which supplies water for 25 million Californians, and engineers were watching for any levee breaches that would affect delta farming and suburban communities near Sacramento and the San Francisco Bay Area, Rizzardo said.

Thomas said, however, the state was not ready to declare the drought finished. He cautioned against putting too much faith in the Drought Monitor data, saying it relied on short-term events such as weather that did not fully reflect California’s water needs.

“It’s not over yet,” Thomas said. “We could go from wet right now to dry for the rest of the winter.”

(Reporting by Sharon Bernstein; Editing by Peter Cooney)