Rounds of rain and mountain snow will barrel into the northwestern United States this Thanksgiving week, threatening to impact holiday travelers and commuters.
While the storm track has shifted south to start this week with rain returning to Southern California and Arizona, a parade of storms will once again take aim at the Northwest starting on Tuesday.
Rounds of rain and mountain snow will then barrel into the Northwest on a nearly daily basis through at least the upcoming weekend.
Depending on the potency of the storms later in the week, gusty winds could also become more of an issue for residents and travelers away from the coast.
As is typical, the heaviest rain and mountain snow will occur from the Cascades westward.
"For the major cities of the I-5 corridor, it will not be cold enough for snow accumulation," AccuWeather Meteorologist Evan Duffey said, "however, the rain will be rather constant this coming week."
This includes in Seattle and Olympia, Washington; and Portland and Medford, Oregon.
The risk of flash flooding may increase by next weekend as each bout of rain further saturates the ground.
Each storm will create headaches for travelers, both on the ground and in the air, during the busiest travel week of the year.
Low visibility and wet roads from the rain will slow down motorists. Any downpours will create more hazards by further reducing visibility and heightening the risk of vehicles hydroplaning when traveling at highway speeds.
"While flight delays and cancellations should not be overbearing, anyone flying will want to keep an eye on their flight for issues," Duffey said.
"Tuesday afternoon is probably the worst time to try to get out of the Pacific Northwest for Thanksgiving as visibilities will be the lowest due to low clouds, fog and periods of heavier rain," he said.
Lighter periods of rain will follow for Wednesday, but areas of low-hanging clouds may remain and cause additional minor flight delays.
More hazards await those planning to travel eastward through the Cascades this week. Despite being a boon for ski resorts and enthusiasts, snow will periodically cover the mountain passes.
"Anyone traveling over the Cascades may want to be prepared for some treacherous conditions," Duffey said. "Snow will be possible much of the week, especially at night."
Duffey listed I-90's Snoqualmie Pass and Stevens Pass as the mountain roads that will become slick at times this week.
"Make sure you are prepared with snow chains and the proper vehicle," he said.
The majority of the Northwest storms will drop far enough to the south to bring showers to San Francisco with snow in the central Sierra Nevada.
However, the rain will stop short of returning to Los Angeles, San Diego and Phoenix.