A winter weather advisory was issued for the Cascades, urging drivers to exercise caution

WESTERN WASHINGTON – The Cascades were hit by heavy snow on Thursday, and more snow is expected through Saturday afternoon, which could make crossing the passes dangerous for motorists.

The eastbound lanes of Interstate 90 over Snoqualmie Pass were closed several times Thursday due to traffic jams and accidents. Drivers attempting to drive over Snoqualmie Pass on Christmas Day also faced heavy snow, traffic and numerous travel restrictions. Due to spinouts and crashes, the pass was also temporarily closed on Christmas Day.

There was compact snow and ice on I-90 at Snoqualmie Pass Thursday morning. For part of Thursday, chains were required for all vehicles, including four-wheel drive vehicles. According to the Washington State Department of Transportation, there were no travel restrictions in either direction of I-90 over the pass as of 8 p.m.

By law, drivers must carry a set of chains in their vehicle and attach them as needed for winter driving. If you don’t have chains, you could be fined $500.

Some drivers were caught in traffic on Thursday.

“We sat behind a couple of trucks for about 15 minutes and it was snowing really hard. When we started moving again, the roads got even worse while we were sitting there,” said Jason NG, who was driving through Snoqualmie.

WATCH: Avalanche forecast explained: How experts assess snow stability in the Cascades

The National Weather Service issued a winter weather advisory for the Cascades for areas above 3,500 feet Friday through early Saturday evening. The weather service said up to 22 inches of additional snow accumulation was possible in some areas, with the heaviest snow expected in areas above 5,000 feet.

Motorists driving over the Cascade passes should prepare for “very difficult to impossible” travel conditions, the NWS said. Motorists are asked to slow down and exercise caution.

The avalanche warning in effect for the Washington Cascades expired at 6 p.m. Thursday, but the Northwest Avalanche Center said there was still a “significant” avalanche danger for most of the Cascades. Thursday evening, a “high” avalanche danger remained on the “west slopes to the south” and on Mount Hood.

KOMO News spoke with the owner of a professional mountain guide service who said Thursday’s very dangerous avalanche conditions meant everyone should stay away from the backcountry.

“You can’t just assume that there are no dangers. That’s one of the main differences when skiing at a ski resort, where essentially the professionals decide whether a particular terrain is safe to ski or not,” said Martin Volken , owner of Pro Ski and Mountain Service.

Get the latest pass requirements from the Washington State Department of Transportation.