Dozens of flights in and out of Northwest cities were canceled Saturday, a stretch of Interstate 5 was turned into a "skating rink" and residents were faced with a fresh load of snow, ice and the fallout from vicious winds. Now the question is: Will it get worse?

Dozens of flights in and out of Northwest cities were canceled Saturday, a stretch of Interstate 5 was turned into a “skating rink” and residents were faced with a fresh load of snow, ice and the fallout from vicious winds.

Now the question is: Will it get worse?

Meteorologists say another storm is headed our way. But whether it will bring snow or rain Sunday will depend largely on the way temperatures fluctuate across the region.

“In the mountains, it’s clear it will be snow,”said University of Washington meteorologist Cliff Mass. “On the coast, it will probably be rain. But what about over us?”

Mass’ best guess is that residents should expect wet snow Sunday, possibly mixed with rain.

But whatever this storm delivers, it will be minor compared to the double-punch of wind and snow that began sweeping across the state Saturday morning and rolled into the Puget Sound area by late afternoon.

“This will be our greatest snowstorm since 1996,” Mass said.

Don’t expect the snow to melt off anytime soon, said Kirby Cook, chief science officer for the National Weather Service in Seattle.

The extreme cold temperatures that have parked over the region will moderate only slightly in the coming week.

“Christmas Eve looks more wet than white,” Cook said. But Christmas Day could bring a mix of snow and rain.

On what was supposed to be the final push for holiday shopping Saturday, the Factory Stores at North Bend mall largely shut down at 5 p.m., rather than the usual 9 p.m., said Tyler Wagner, manager at the Mt. Si Board and Skate.

He said his store was staying open until 7 p.m. because customers were still coming in, despite high winds and snow.

“It’s crazy, man. It’s like you can’t even see across the parking lot.”

Up to 3 feet of snow was forecast for the Olympic Mountains, with up to 8 inches in portions of the Puget Sound metropolitan area. Winds were gusting up to 60 mph in the Strait of Juan de Fuca by late afternoon, and up to 45 mph at Gold Bar and Snoqualmie Pass, said Cook.

As heavy snow advanced eastward, Interstate 5 near Olympia was turned into a “skating rink,” according to the State Patrol. Ten collisions, none involving injuries, snarled traffic along a six-mile stretch of freeway between Dupont and Lacey.

Alaska and United Airlines collectively canceled more than 50 flights to and from Seattle, Portland and Vancouver, B.C. Flights on Saturday and Sunday were affected.

The storm came with ample warning, and was a relatively easy target for meteorologists.

“It’s a relatively strong system that’s been out there for several days,” Mass explained. “The computer models seemed to have a good handle on this one.”

That allowed local governments and agencies time to prepare.

Pierce County Executive John Ladenburg issued a pre-emptive emergency declaration Saturday afternoon, freeing up resources and money to help open five emergency shelters.

Volunteers with four-wheel-drive vehicles were mobilized to ferry doctors, nurses and other critical medical personnel to area hospitals, said Sheri Badger, spokeswoman for the county’s emergency management department.

Seattle’s three severe-weather shelters in downtown will remain open at least through Monday, said David Takami, spokesman for the city’s Human Services Department.

As the snow began piling up, the Seattle Symphony made a last-minute decision to cancel its Saturday night performance of Handel’s “Messiah” at Benaroya Hall. But a performance at 2 p.m. Sunday was still on, said spokeswoman Rosalie Contreras.

Seattle University postponed its men’s basketball game with Linfield College of McMinnville, Ore., at the campus Connolly Center Saturday night. The game was tentatively rescheduled for the second week in January.

In addition to mobilizing its own service crews to deal with expected power outages caused by high winds, Puget Sound Energy called in an additional 40 line crews and 12 tree-trimming crews that arrived Saturday afternoon from Montana, Oregon and Canada, said spokeswoman Davina Gruenstein.

The town of Enumclaw, in the Cascade foothills near Mount Rainier, was predicted to be ground zero for the highest winds — a common phenomenon when cold air from Eastern Washington spills over the mountains and rushes down the passes. The winds were slower to develop Saturday than forecast but were expected to be particularly destructive in the foothills, with gusts up to 75 mph.

Enumclaw’s Safeway gas station ran out of all but its highest grade of gas by 10:30 a.m. Saturday, as local residents filled cars, trucks and gas cans in preparation for the storm.

Rob Neuman stocked up on fuel and food, including hot dogs and other meat for the barbecue outside in case his stovetop and oven lose power.

“We were without electricity for a week last time,” he said of a big storm in 2003. Neuman bought 26.5 gallons of gas for a generator and a four-wheeler/ATV. “We go out and play in the snow.”

Dennis Bacon and his sons, Brett and Cody, nailed boards over the east-facing windows of their floor-covering business, Plateau Floors To Go. It’s the first time they’ve ever taken that step. “We get real gusty winds here, and the building is old and a couple windows are cracked,” Dennis explained.

Terry Tomt, who lives just outside Enumclaw in King County, was prepared with a generator and a wood-burning stove. “You don’t want to shrug it off, because it can be brutal out here in the wind.” He’s only used the generator once before, but said he fired it up yesterday to make sure it works.

Winds were expected to be much lighter along the urban Puget Sound corridor, averaging about 20 mph with gusts up to 30 mph, said Cook, of the Weather Service.

When the snow fell in Phinney Ridge Saturday evening, residents took to neighborhood streets on foot.

Many descended on the neighborhood True Value hardware store in a sometimes-futile search for supplies. “We’re out of all the S’s … we’re out of salt, sand, shovels and scrapers,” said clerk Brian Genung, who estimated the store turned away almost 300 people.

A few doors down, at Ken’s Market, people were grabbing up supplies and basic food items. The store was cooking up extra rotisserie chickens to meet the demand.

One Phinney Ridge resident who spent 10 years in New York, Jason Twill, 33, said the city of Seattle is not prepared for snowstorms. When a storm hits, “it’s a new revelation,” he said. “There’s no salt on the roads, and companies shut down.” But he was prepared. “We’ve got movies, soup and hot cocoa,” he said

A hallmark of the storm is the wide range of snow accumulation expected across the Puget Sound region, Mass pointed out: Areas closest to the foothills were expected to receive the least snowfall, with Western Puget Sound and the Olympics hit the hardest. It’s all a matter of topography, Mass explained.

Cold air from the east is colliding with a low-pressure system moving in from the west.

As the air pours over the Cascades and sinks, it warms and loses moisture, which tends to dampen precipitation. That effect diminishes farther from the mountains. When the cold air hits the eastern side of the Olympics, it starts to rise and cool, which intensifies precipitation, said Mass, who spent much of Saturday consulting computer models and radar grids and updating his new weather blog — which received a record 24,000 hits Saturday.

“It’s wonderful,” he said. “People are really getting into this.”

Seattle Times staff reporters Warren Cornwall, Christine Willmsen, Percy Allen and Carol Pucci contributed to this story.