Storm train brings snow, flood threat to the West
The fall and early winter have been active with multiple rounds of rain and mountain snow in the West. While this has helped to alleviate any drought conditions and boosted the snowpack, the ground is becoming saturated. AccuWeather meteorologists warn that the continued precipitation will increase the risk of flooding and mudslides.
With Christmas this week, more people will be traveling by plane, train and automobile. The repeated rounds of rain and snow are likely to cause people to drive more slowly and also delay airport travel.
"Travelers immediately ahead of the Christmas holiday will have to contend with wet roads along much of the West coast, from the Canadian border to California," said AccuWeather Senior Meteorologist Heather Zehr.
 |
On Tuesday and Tuesday night, a new storm will come ashore and precipitation could eventually fall as far south as Los Angeles.
"Rain will be heaviest from Monday night into Tuesday morning across Northern California and southwestern Oregon, and falling snow levels will allow rain to change to snow down to many passes," explained Zehr.
Have the app? Unlock AccuWeather Alerts™ with Premium+
"While amounts will not be excessive, roads will become slippery quickly after the snow begins and it will come down heavily at times," cautioned Zehr.
Oftentimes, snow levels rise and then fall throughout the duration of storms in the West. This can lead to other hazards besides just snow-covered and slippery roads.
 |
"Shifting snow levels falling over the high country will increase the risk of avalanches with each storm into next week as the increasing snow cover becomes more unstable," warned AccuWeather Senior Meteorologist Alex Sosnowski.
For anyone traveling in the West on Christmas Day, most of the region will enjoy a brief respite from the rain and snow. An exception will be some snow showers in the Intermountain West. By late in the day and overnight, the next storm will be barreling into the Pacific Northwest.
 |
"Seattle will have periods of rain in the afternoon, while Portland can have a couple of showers late in the day," said Zehr.
That next storm is also likely to have a fair amount of wind with it, especially as it initially moves inland on Wednesday night and Thursday morning. With saturated ground and wind, there will be a risk for at least localized power outages. The highest risk would be along the immediate coast, where winds are expected to be the strongest.
 |
With storms through this week and potentially even into the weekend, rain amounts will add up.
"Rain totals through this storm series through the end of the week will be 6-10 inches along the coast from Vancouver Island through Washington and most of Oregon, as well of Northern California," said Zehr, "This will lead to rises on small streams with increasing risk after each storm."
 |
"As the storm parade continues, each successive storm will increase the flow and water levels of the short-run rivers that flow out of the Cascades, Coast Ranges, and Olympics," Sosnowski said, "Some rivers may flood unprotected areas along their banks."
 |
Even though snow levels will rise and fall, the highest peaks will likely have snow through the duration of the storms.
"Above pass level in the mountains, especially the Washington Cascades and the Sierra Nevada, snow will likely total 2-4 feet," said Zehr.
Looking farther down the road, there may be a break in the storm parade toward New Year's Eve and New Year's Day.
Want next-level safety, ad-free? Unlock advanced, hyperlocal severe weather alerts when you subscribe to Premium+ on the AccuWeather app. AccuWeather Alerts™ are prompted by our expert meteorologists who monitor and analyze dangerous weather risks 24/7 to keep you and your family safer.
