Officials in Washington are pleading with travelers to avoid the entire Cascade Mountains area during the Thanksgiving holiday weekend, as road crews continue work to clear a Nov. 6 rockslide near Snoqualmie Pass on Interstate 90.

According to a spokesperson for the Washington Department of Transportation, traffic jams as long as 30 miles could develop as the number of motorists on the road increases for the Thanksgiving weekend.

“It is with heavy hearts that we’re asking travelers not to use the passes over the Thanksgiving weekend,” Linda Mullen, a spokeswoman for the WSDOT, told “Land Line Now.”

“We’ve run the numbers, and if the usual number of people were to drive over the passes, they would be stuck in traffic in the mountains for many, many, many hours.”

Mullen said that even if most travelers avoid the mountain passes, those who do travel them should still expect five-hour delays.  

Bruce Morrison, a spokesperson for Power Transport in Spokane , told “Land Line Now” that he hopes area trucking companies plan ahead for the delays and closures.

“Everybody out here’s planning on the delay, and they’re trying to work their schedule around that,” Morrison said. “They’re either taking alternate routes or just figuring it’s going to be a little bit longer. I hope they don’t have the traffic they’re counting on.”

One eastbound lane and one westbound lane are open on I-90, with a speed limit within the work zone of 35 mph. Oversize truck loads are not allowed.