Winter storm to bring snow, frigid temps to western Washington

SEATTLE — Major weather changes are underway in western Washington starting late Sunday and continuing throughout the upcoming business week.

Expect heavy mountain snow, gusty winds, frigid temperatures and even the possibility of light snowfall in the lowlands. Due to Monday’s strong winds and heavy mountain snow, KING 5’s First Warning Weather Team designated Monday as the day First Warning Weather Day due to weather effects.

Dense mountain snow will be one of the major impacts of this system. Snow accumulation begins Sunday afternoon and continues through Tuesday afternoon.

By the end of Tuesday, 1 to 3 feet of snow is expected for the Cascades above 2,000 feet, including passes where both Snoqualmie Pass and Stevens Pass will see up to 1 foot of snow. Some of the higher Cascade peaks can see snow accumulation up to nearly 4 feet.

Snow levels on Sunday afternoon spiked to about 4,000 feet, allowing Snoqualmie Pass to have mixed, if not all, rain, while Stevens Pass was all snow, but the snow level quickly dropped as the air got colder. overflow on Monday.

Snow levels dropped to 3,500 feet Monday morning, continuing throughout the day, and by Tuesday morning, snow levels will drop as low as 1,000 feet.

Due to heavy snowfall and gusts of up to 50 mph, the Winter Storm Warning will be in effect from Sunday afternoon through Tuesday afternoon. During the Winter Storm Warning, hazardous road conditions may occur due to heavy snow accumulation and limited visibility due to wind blowing around the snow.

Strong winds will not be limited to mountain passes. Strong, gusty winds are forecast in all of western Washington starting Monday.

Widespread gusts of 30 to 40 mph are expected Monday afternoon with stronger winds of up to 50 mph near the Juan de Fuca Strait and for some island communities. All of the Puget Sound lowlands, including Seattle and Everett, could see gusts of up to 40 mph Monday afternoon and evening.

Initial winds on Monday will blow from the south before changing to the west later in the day as a cold front sweeps the area.

While winds eased Tuesday, gusts were still increasing at about 20 to 30 mph across the region. The strongest winds on Tuesday will benefit the mountain passes, Cascade cleft areas and in the west Whatcom County extends westward into San Juan County and near the southern coast of the Strait of Juan de Fuca.

Wind warnings are likely to be issued Monday by the Seattle National Weather Service. Make sure you go ahead and secure lawn furniture and trash cans.

The key weather story that you will feel and will affect all of western Washington is the cold temperatures this working week.

The coldest temperatures come Wednesday through Friday when a modified arctic air mass enters the region. This will keep temperatures high in the 30s with lows falling in the 20s.

This cold wave high will set some new daily record highs and lows at some point when temperatures are about 15 degrees below average. The average high in Seattle for this time of year is 51.

The temperature will feel colder due to high winds. Cold winds are expected to subside in the teenage years and even in some areas.

With temperatures this cold, please bring your pets indoors, protect pets and plants, check on your neighbors and practice safe heating practices while warming your home. .

While heavy mountain snow is an important weather story, there is still a small chance of light snowfall in the lowlands around Puget Sound.

The best chance for snow in the lowlands is Tuesday afternoon and evening when cold air hits western Washington. Any residual moisture could turn into a rain/snow mix and possibly all light snowfall from Tuesday evening to early Wednesday morning along with any remaining moisture.

As always with these settings, it’s a race between cold air and humidity. Most of the moisture will leave the lowlands before the air is cold enough to make snow.

Any snowy lowlands are not expected to spread or create meaningful accumulation, and most areas don’t even see snowflakes.

Another small change to lowland snow will arrive late Friday to early Saturday with our next weather generator but this will quickly turn to rain on Saturday as temperatures warm. . The event is still a few days away so there is a chance of moderate to high uncertainty around the possibility of snow on Friday.