Recent snow and wind combined with mild air on Saturday will set the stage for avalanches into Monday.
Mild air will surge northward into Oregon and Washington on Saturday. A storm system will then bring rain across all but the highest elevations Saturday night before snow levels gradually lower Sunday into Monday.
Combined with wind and new snowfall over the past 24-48 hours, above-freezing temperatures and rain in all but the higher elevations Saturday night into Monday will trigger a considerable threat for avalanches.
The highest threat for avalanches will be found in the Olympic Mountains of western Washington and both the western and eastern slopes of the Cascades in Washington and Oregon.
Avalanche impacts across these areas include locations above, near and below the tree line. Those who plan to do any back-country skiing or hiking through the mountainous terrain should be aware that dangerous avalanches can occur with little or no warning.
In fact, The Northwest Avalanche Center says, "careful snowpack evaluation, cautious route-finding and conservative decision-making is essential."
This image from the The Northwest Avalanche Center shows the danger from loose wet avalanches.
The most serious avalanche concern will come from Loose Wet avalanches, which occur when water is running through the snowpack due to rain or melting, and it is released at or below a trigger point.
Though still possible, it should also be noted that impacts from possible avalanches in developed ski areas and terrain near highways are somewhat lower due to ongoing avalanche mitigation techniques.
As snow levels lower gradually into Monday, the avalanche threat will continue into at least Monday.
Story thumbnail image: An avalanche danger sign closes off a specific area of the woods due to avalanche risk, on Corona Bowl, known for its extreme skiing, at Eldora Mountain Resort, near Nederland, Colo., Wednesday, Feb. 26, 2014. Lots of new snow and strong winds in the past month have fueled dangerous conditions from the Cascades to the Rockies, prompting forecasters to issue warnings of considerable or high avalanche dangers for many areas outside of established ski areas. (AP Photo/Brennan Linsley)
As a large storm rolls out of the Plains and Midwest, a swath of snow, ice and travel disruptions will extend into the Northeast starting on Sunday evening.
A new storm will form over the weekend across the Plains and will spread snow and ice eastward through the Midwest.
As a snowstorm unraveled from Texas to North Carolina and Virginia, snow and ice left a trail of disruption on Wednesday into Thursday.
Residents in Spokane, Washington, recently caught sight of the unique phenomenon known as "hole punch" clouds that cause a gaping hole in the otherwise cloudy sky.
Storms will continue to affect the West through this weekend and into next week with rounds of precipitation for some needy areas as well as trouble for travelers.
While much of central and eastern North America is still locked in a deep freeze, the warmth cascading across the Pacific Northwest in recent weeks has sparked the early flowering of sakura blossoms in the region.
New England (1717)
First of a series of storms of The Great Snow which finally left about 36" on ground, held Boston snowbound for 3 weeks. Great barometric depression moved across Arkansas, Tennessee, Missouri and Illinois. Lowest pressure 28.71" at Springfield, IL.
Harrisburg, IL (1999)
A thunderstorm wind gust to 80 mph causing a roof to be blown off a house and a car to be blown off the road.