The torrential rain that fell on much of California in recent days recharged rivers, filled storage tanks and prepared the ground for the next storm, providing what many climate experts say is an auspicious start to the winter.

But the rainfall, which set records in some northern cities, was not nearly enough to end the state’s deep drought, now affecting 37 million of California’s 40 million residents.

One reason is simple. The deficit of water from a drought now entering its third year is too great to be made up with just one storm, no matter how powerful it may have been. Compounding the problem, California’s warming climate is undermining its ability to dent its droughts in the long term, even when the rains do come.

The storm did leave several feet of snow in the high Sierra Nevadas. But warmer-than-usual weather meant that snow did not accumulate at lower altitudes where it once would have. The Sierra snowpack is the key to California’s water, filling rivers and reservoirs with a steady stream of cool water as it melts in the spring.

“The whole system is built around the assumption there will be snow,” said Michael Wara, a senior research scholar at Stanford’s Woods Institute for the Environment. “This storm brought mostly rain to the Sierra. And that’s climate change.”

Wara received 16 inches of rain over three days at his home in Marin County, just over the Golden Gate Bridge from San Francisco, where the storm flooded streets and knocked out power to some. Marin, which has imposed some water restrictions on its residents, is among a handful of Bay Area and Northern California counties feeling the drought most acutely.

As a result, those counties, among some others, have been highly susceptible to wildfire as the drought persists. Fires burned almost 2.5 million acres in California this year, leaving large “scars” where the vegetation holding the top soil together is gone. Those areas are now at risk of sliding away in heavy rains as mud and debris flow.

“This rainstorm completely, decisively ended the fire season in Northern California,” Wara said. “We can all sleep better at night.”

Wara said the rain amounted to a “20 percent down payment” toward ending the drought. The benefits could be seen Tuesday across Northern California with refreshed reservoirs and suddenly fast-flowing rivers after a summer of stagnation.

Lake Oroville, one of the state’s largest reservoirs where more than a hundred houseboats had to be removed earlier this year because of historically low water levels, rose 20 feet over the past week. Lake Mendocino, which supplies Mendocino County and others along the North Coast, added several thousand acre-feet of water.

The Russian River threatened to spill its banks. The river supplies many farmers in California’s grape-growing wine country. Earlier this year, farmers were ordered to stop drawing from the river because of its low levels.

“We’re at such a serious deficit that we’re going to be facing significant water shortages in the near future,” said Howard Brown, a National Oceanic and Atmospheric Administration policy adviser on West Coast fisheries. “That said it is a very good start to the year.”

Brown was drenched with more than six inches of rain at his home in Folsom, where a large reservoir has dipped to historic lows over the summer. The reservoir reached a level marking just over half its average supply with the rains.