Seattle, Washington -- There was an unusual sight at the world-famous Pike Place Market in Seattle Saturday morning: about 4 inches of snow on the ground already. Two to six more inches of snow were in the forecast as a winter storm pounded the state.

Washington Governor Jay Inslee declared a state of emergency Friday for the entire state and urged people to stay off the roads. People cleared grocery store shelves as they rushed to prepare.

One county official warned the storm could be a "once every decade or two occurrence," CBS News' Carter Evans reported.

As it moved it, the storm obscured Seattle's famous Space Needle from sight. In the city's Queen Anne neighborhood Friday night, one bus had to bail off its route after it got stuck on a snow-covered street. Some roads were closed completely overnight Friday into Saturday.

More than six inches of snow fell at Seattle-Tacoma International Airport. At least 200 flights were canceled to accommodate the winter weather, and a snowball fight unfolded between workers on the tarmac.

More flight cancellations are expected out of Seattle Saturday. By early morning, 80 were already canceled.

Conditions are likely to let up later in the day, but another storm system is expected to push across the area late Sunday. That system could bring even more snow.