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Frank Gehrke, chief of snow surveys for the Department of Water Resources, crosses a snow covered meadow as he does the first snow survey of the year at Echo Summit Calif., Wednesday, Jan. 2, 2013. (AP Photo/Rich Pedroncelli)

December’s storms have boosted the spirits of California’s water watchers, with the season’s first Sierra Nevada water survey revealing a snowpack deeper and wetter than normal.

The ritual trek along Highway 50 near Lake Tahoe to survey the state’s water outlook revealed more than four feet of soggy snow, with moisture 34 percent above average.

That compares to last year’s depth of 0.14 inches — scarcely more than a few scattered patches.

“We are doing great — off to an excellent start,” said Ted Thomas of the state’s Department of Water Resources. Last year was dry, except for late spring showers.

The crucial reading means the state will be able to deliver at least 40 percent of the supply requested by state water project members this year — and it expects to give more, as — and if — winter storms accrue.

The measurements are particularly important because California is entering a fourth year of drought.

The gusting Pacific storms nudged San Jose’s cumulative seasonal rainfall to 7.19 inches, a big splash beyond last year’s 1.55-inch total. So far, Concord has had 9.64 inches; Livermore, 8.29 inches, and Oakland, 10.63 inches. This time last year, none of those cities had more than two inches.

The next week or two are expected to be dry, with temperatures ranging from the low 30s to low 60s, said Austin Cross of the National Weather Service in Monterey. He couldn’t predict whether dry skies will persist

through January.

That’s no cause for concern — it fits a pattern of a midwinter dry spells alternating with rains, Cross said.

Fresno farmers rejoiced while keeping a close eye on thermometers. On Wednesday night, to prevent freezing delicate oranges, huge fans blew air through the orchards and warm ground water poured through irrigation channels.

“This is fantastic news,” said Fresno County Farm Bureau director Ryan Jacobsen, who views the snowy Sierra from his office. “The San Joaquin Valley is considered a desert. We would not be in existence if not for the snowpack above us.”

Welcome signs of winter are everywhere in the Bay Area. White-blossomed milk maids and manzanita shrubs are blooming along Mount Diablo’s Mitchell Canyon and Donner Canyon areas. And three beloved waterfalls are cascading down the flanks on the Clayton side of the mountain, visible to hikers on the Falls Trail, said naturalist Leslie Contreras.

Wednesday’s clear winter skies gave Diablo’s visitors views all the way to Mount Shasta, Mount Lassen, the Sierra and the Farallon Islands.

Fungus fans are thrilled by the appearance of mushrooms, delicious when they’re not killing you. Our coastal mountains are home to more than 1,000 species, which start bursting through the soil two to three weeks after the first rains.

“Rains are heaven sent,” said mycologist Phil Carpenter, “prime minister” of the Fungus Federation of Santa Cruz, who is busy preparing for the annual Jan. 11-13 Fungus Fair. “This is our time to glory.”

Other harbingers of the season, banana slugs, have emerged from their summer hiding spots — finally able to travel along moist routes.

Chinook salmon are swimming up Mt. Tamalpais’ Marsh Creek for the first time in 60 years, weary after spawning and a long journey from the ocean.

“December was very kind and generous to California’s rivers and streams,” said Steve Rothert, California director American Rivers.

Early rains are also important for local steelhead trout, said environmentalist Matt Stoeker, who monitors the Peninsula’s San Francisquito Creek. “Having a heavy flow in December means fish are able to get out of the Bay and upstream to spawn.”

Migratory birds are arriving in the Bay, a critical stop along the Pacific Flyway.

Stunning white snow geese, visiting from the Arctic, were in a flock of Canada geese at the Sunnyvale Baylands Park. Other avian winter visitors include red-breasted nuthatch near Mount Madonna and pine siskins feeding on redwood cones atop tall trees along Highway 152. In the Central Valley, vast flocks of sandhill cranes and tundra swans have gathered.

But water-lovers are trying to temper their enthusiasm in a still-young winter.

“We still have a lot of season left to go,” said Jacobsen. “We’re really encouraged, but the rains have to continue for it to be a true success.”

Contact Lisa M. Krieger at 650-492-4098.

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