SEQUIM, Wash.—The Olympic Mountains that tower above this farming community normally rank among the snowiest places in the U.S., with drifts several feet deep lingering into June.

But this year, the Olympics recorded virtually no snow in all but the highest peaks. The May 1 reading of zero snowpack in the rugged range northwest of Seattle was the lowest since records there began in 1948, and came as statewide snow accumulations totaled a paltry 16% of normal.

The snow drought, which has afflicted much of the Northwest, is saddling the region with some of the difficulties California endures in its four-year water drought: threats to wildlife, heightened fire danger and agriculture losses.

"It's really turning out to be pretty appalling, the conditions we have," said Teresa Scott, drought coordinator for the Washington Department of Fish & Wildlife.

The state received plenty of precipitation but it came largely as rain because air temperatures were as much as 7 degrees Fahrenheit higher than normal. The resulting lack of snow presents a real problem.

Mountain snowpacks act as frozen reservoirs across the West, and any long-term reduction in their size could have a profound impact on the region.

While the ample rainfall has filled the reservoirs of larger cities, many agriculture and rural areas are more reliant on water from streams and rivers to get through the dry summer months. Less melting snow to feed the streams means less runoff for those communities.

State climatologists say the warming pattern could be tied to an El Niñ o condition in the equatorial Pacific, which causes ocean waters to heat up along the West Coast. Some scientists say climate change could be a factor.

Long-term climate models by Washington State University forecast a 4 degree rise in average temperatures in the state by 2070, with precipitation remaining about the same as it was in the past winter.

"This is a great window to see what could be a typical winter for us 60 years from now," said Bill Baccus, a scientist at Olympic National Parkwhile hiking recently past green grass on a ridge that normally would be covered in snow.

The snow drought, so far, isn't exacting the same severe consequences as the California drought. Reservoirs there have become so depleted after years of below-normal rain and snow that state and federal officials have sharply reduced water supplies to both cities and farms, and the economic losses to agriculture alone are estimated in the billions of dollars.

Still, Washington farmers are being hit hard.

The state Agriculture Department estimates the sector will lose 12% of its annual $10 billion crop value this year, or $1.2 billion.

Gov. Jay Inslee in May declared a drought disaster and asked state lawmakers to allocate emergency aid for farmers and others affected. The Legislature approved $16 million in aid.

Washington hasn't suffered a major drought in a decade; reservoirs near Seattle and other major populated areas are brimming after receiving near normal precipitation during the past few months. But without snowmelt to feed them, many streams and rivers are running as much as two-thirds below their normal levels. That is triggering economic and environmental impacts across the Evergreen State.

Whitewater rafting on the Spokane River, for example, ended in early June, about six weeks ahead of normal.

The outfitter Wiley E. Waters is still running scenic cruises on a former whitewater stretch near Spokane, Wash., but not enough to make up for the lost business, said owner Josh Flanagan. "It's a little disappointing, but we have to take what we can get," he said.

In the Yakima River Basin of central Washington, the Roza Irrigation District cut off all water to its 1,700 farmers for three weeks in May, said general manager Scott Revell.

The U.S. Bureau of Reclamation, which operates local reservoirs, forecasts that farmers holding the most junior water rights in the basin will get only 44% of their allocations this year. The basin's farmers grow some of the state's highest-value crops, including cherries, apples and wine grapes.

Some farmers are drawing more water from wells, which can be costly, or fallowing land.

Tom and Holly Clark need water to irrigate pastures for their cattle and other livestock on a 113-acre family spread near Sequim. They agreed to leave their share of runoff in the Dungeness River to help preserve more for returning salmon later this year, but doing so will add about $1,500 in costs from running well pumps, Mrs. Clark said. For now, the extra costs are being covered under an agreement with a nonprofit water trust.

"It's an added expense, and there's also the overall worry of what else is coming," said Mrs. Clark, 52 years old. "This is the third year in a row where the weather has been warmer than normal, although the first with no snow."

As many as 1.3 million pink salmon are forecast to return to the Dungeness to spawn this year, but state biologists are concerned the water will become too warm and shallow for the fish to travel upstream and reproduce.

At Olympic National Park, grasses and other vegetation is drying out weeks sooner than normal because of the lack of snow, depriving deer, bears and other wildlife of important food sources, Mr. Baccus said.

"The real question is how are these animals going to do in the fall," he said. "We've never observed a year like this, so we don't really know."

Write to Jim Carlton at Jim.Carlton@wsj.com

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