Issued: 7:45 AM PST Friday, February 23, 2018
by Dennis D'Amico

Jump to: Weather Forecast I Snow/Freezing Level I Precipitation I Free Winds 5k I Free Winds 9k

Weather Synopsis for Friday & Thursday

It's cold out there!  Mountain temperatures across the region are nearly universally in the single digits this morning. Weak shortwave ridging over the area will quickly be replaced by increasing high and mid clouds today with lowering cloud bases through the day. Light snow should develop over the north Cascades and Olympics later this morning and spread south during the day as a moisture starved frontal band sweeps through in NW flow aloft.  Crest level winds will increase quickly this afternoon, with westerly winds increasing at all elevations overnight. 

The trailing upper level trough will provide a more significant bump in precipitation tonight as it crosses the region, with light to moderate snow showers developing after midnight and continuing through Saturday morning. Showers should quickly decrease on Saturday as the trough digs south and east of our area, but weak convergence will keep light snow accumulations continuing in the Stevens to Snoqualmie Pass corridor.   

Another frontal system will cross the area Saturday night, this one stronger than the previous iteration with snow and especially winds increasing after midnight as the jet stream takes direct aim at Washington State. A slight warming trend will take place from about Snoqualmie Pass to Mt. Hood during the early morning hours of Sunday before the frontal passage. 

Weather Forecast

Olympics
Friday Cloudy whit light snow developing this morning. Winds increasing in the afternoon.
Friday Night Light snow showers increasing after midnight. Windy.
Saturday Light to moderate snow showers in the morning becoming scattered light snow showers in the afternoon. Winds decreasing.
Washington Cascades near and west of the Crest including Stevens, Snoqualmie and White Passes
Friday Increasing clouds with bases lowering in the afternoon. Light snow developing north Cascades and spreading south during the day. Crest level winds increasing in the afternoon.
Friday Night Light snow showers becoming light to moderate after midnight. Windy.
Saturday Light to moderate snow showers in the morning becoming scattered light snow showers in the afternoon. Winds decreasing.
East Slopes of the Washington Cascades
Friday Increasing clouds with bases lowering in the afternoon. Light snow developing northeast Cascades and spreading south during the day. Crest level winds increasing in the afternoon.
Friday Night Light snow showers becoming light to occasionally moderate after midnight. Windy.
Saturday Light to occasionally moderate snow showers in the morning becoming mostly cloudy with isolated light snow showers in the afternoon. Winds decreasing.
Mt. Hood
Friday Mostly sunny in the morning with increasing clouds during the day and light snow developing late afternoon. Increasing alpine winds in the afternoon.
Friday Night Light snow showers becoming light to moderate after midnight. Windy.
Saturday Light to moderate snow showers through mid-day becoming scattered light snow showers in the afternoon. Windy.

Snow/Freezing Level (ft)

Hurricane Ridge Mt. Baker Washington Pass Leavenworth Stevens Pass Snoqualmie Pass Mt. Rainier, Crystal & White Pass Mt. Hood
Friday Morning Snow Level 0' 0' 0' ' ' 0' ' 0'
Friday Afternoon Snow Level 500' 0' 0' ' ' 0' ' 500'
Friday Night Snow Level 500' 0' 0' ' ' 500' ' 500'
Saturday Snow Level 500' 0' 0' ' ' 500' ' 1000'
Hurricane Ridge Elevation
Friday Morning Snow Level
0'
Friday Afternoon Snow Level
500'
Friday Night Snow Level
500'
Saturday Snow Level
500'
Saturday Night Snow Level
2500'
Mt. Baker Elevation
Friday Morning Snow Level
0'
Friday Afternoon Snow Level
0'
Friday Night Snow Level
0'
Saturday Snow Level
0'
Saturday Night Snow Level
1000'
Washington Pass Elevation
Friday Morning Snow Level
0'
Friday Afternoon Snow Level
0'
Friday Night Snow Level
0'
Saturday Snow Level
0'
Saturday Night Snow Level
1000'
Leavenworth Elevation
Friday Morning Snow Level
'
Friday Afternoon Snow Level
'
Friday Night Snow Level
'
Saturday Snow Level
'
Saturday Night Snow Level
'
Stevens Pass Elevation
Friday Morning Snow Level
'
Friday Afternoon Snow Level
'
Friday Night Snow Level
'
Saturday Snow Level
'
Saturday Night Snow Level
'
Snoqualmie Pass Elevation
Friday Morning Snow Level
0'
Friday Afternoon Snow Level
0'
Friday Night Snow Level
500'
Saturday Snow Level
500'
Saturday Night Snow Level
1500'
Mt. Rainier & Crystal Elevation
Friday Morning Snow Level
'
Friday Afternoon Snow Level
'
Friday Night Snow Level
'
Saturday Snow Level
'
Saturday Night Snow Level
'
Mt. Hood Elevation
Friday Morning Snow Level
0'
Friday Afternoon Snow Level
500'
Friday Night Snow Level
500'
Saturday Snow Level
1000'
Saturday Night Snow Level
2000'

* Easterly flow in the Cascade Passes can cause locally lower Snow or Freezing levels than areas further west.
Freezing Level is when no precipitation is forecast.

Precipitation Forecast

Thursday Thursday
Hurricane Ridge 0.25 - 0.50 0.25 - 0.50
Mt Baker Ski Area 0 - 0.75 0.50 - 0.75
Washington Pass 0.25 - 0.50 0.25 - 0.50
Stevens Pass 0 - 0.50 0.75 - 1.00
Snoqualmie Pass 0 - 0.50 0 - 1.00
Mission Ridge LT 0.25 LT 0.25
Crystal Mt LT 0.25 0 - 0.50
Paradise 0 - 0.75 0 - 1.00
White Pass 0.25 - 0.50 0 - 0.75
Mt Hood Meadows 0.50 - 0.75 0 - 1.00
0 - 0.75 1.00 - 1.50

Free Winds at 5000' (mph)

Hurricane Ridge Mt. Baker Stevens to Snoqualmie Pass Mt. Rainier Mt. Hood
Friday Morning W 0 - 10 SW 0 - 10 W 0 - 10 --- - W 0 - 10
Friday Afternoon SW 20 - 30 S 10 - 20 SW 15 - 30 --- - W 15 - 25
Friday Night W 15 - 30 SW 15 - 25 WSW 25 - 40 --- - WSW 30 - 40
Saturday Morning W 10 - 20 W 0 - 10 NW 10 - 20 --- - WNW 25 - 40
Saturday Afternoon WSW 15 - 25 SW 10 - 20 W 10 - 20 --- - W 25 - 35
Saturday Evening SW 20 - 30 SW 20 - 30 SW 25 - 35 --- - W 35 - 45
Hurricane Ridge Elevation
Friday Morning W 0 - 10
Friday Afternoon SW 20 - 30
Friday Night W 15 - 30
Saturday Morning W 10 - 20
Saturday Afternoon WSW 15 - 25
Saturday Evening SW 20 - 30
Saturday Night W 30 - 40
Mt. Baker Elevation
Friday Morning SW 0 - 10
Friday Afternoon S 10 - 20
Friday Night SW 15 - 25
Saturday Morning W 0 - 10
Saturday Afternoon SW 10 - 20
Saturday Evening SW 20 - 30
Saturday Night SW 30 - 40
Stevens and Snoqualmie Pass Elevation
Friday Morning W 0 - 10
Friday Afternoon SW 15 - 30
Friday Night WSW 25 - 40
Saturday Morning NW 10 - 20
Saturday Afternoon W 10 - 20
Saturday Evening SW 25 - 35
Saturday Night WSW 35 - 50
Mt. Rainier Elevation
Friday Morning --- -
Friday Afternoon --- -
Friday Night --- -
Saturday Morning --- -
Saturday Afternoon --- -
Saturday Evening --- -
Saturday Night --- -
Mt. Hood Elevation
Friday Morning W 0 - 10
Friday Afternoon W 15 - 25
Friday Night WSW 30 - 40
Saturday Morning WNW 25 - 40
Saturday Afternoon W 25 - 35
Saturday Evening W 35 - 45
Saturday Night SW 40 - 50
Hurricane Ridge Direction - Speed
Friday Morning W 0 - 10
Friday Afternoon SW 20 - 30
Friday Night W 15 - 30
Saturday Morning W 10 - 20
Saturday Afternoon WSW 15 - 25
Saturday Evening SW 20 - 30
Saturday Night W 30 - 40
Mt. Baker Direction - Speed
Friday Morning SW 0 - 10
Friday Afternoon S 10 - 20
Friday Night SW 15 - 25
Saturday Morning W 0 - 10
Saturday Afternoon SW 10 - 20
Saturday Evening SW 20 - 30
Saturday Night SW 30 - 40
Stevens and Snoqualmie Pass Direction - Speed
Friday Morning W 0 - 10
Friday Afternoon SW 15 - 30
Friday Night WSW 25 - 40
Saturday Morning NW 10 - 20
Saturday Afternoon W 10 - 20
Saturday Evening SW 25 - 35
Saturday Night WSW 35 - 50
Mt. Rainier Direction - Speed
Friday Morning --- -
Friday Afternoon --- -
Friday Night --- -
Saturday Morning --- -
Saturday Afternoon --- -
Saturday Evening --- -
Saturday Night --- -
Mt. Hood Direction - Speed
Friday Morning W 0 - 10
Friday Afternoon W 15 - 25
Friday Night WSW 30 - 40
Saturday Morning WNW 25 - 40
Saturday Afternoon W 25 - 35
Saturday Evening W 35 - 45
Saturday Night SW 40 - 50

Directions above indicate the direction the wind blows from on the 16-point cardinal scale. These winds indicate "free" winds, or those winds in the atmosphere not influenced by terrain. Topographical effects may produce greater or lower wind speeds in certain locations as well as significant variations in direction.

Free Winds at 9000' (mph)

Mt. Baker Washington Pass Stevens to Snoqualmie Pass Mt. Rainier Mt. Hood
Friday Morning NW 15 - 25 NW 15 - 25 NW 20 - 30 --- - NNW 20 - 30
Friday Afternoon W 30 - 40 WSW 30 - 40 W 45 - 60 --- - NW 45 - 60
Friday Night W 15 - 25 WSW 20 - 30 WSW 30 - 40 --- - W 40 - 50
Saturday Morning WNW 10 - 20 W 10 - 20 NW 20 - 30 --- - NW 40 - 50
Saturday Afternoon W 15 - 25 W 10 - 20 NW 25 - 35 --- - WNW 35 - 45
Saturday Evening WSW 25 - 35 WSW 40 - 50 W 35 - 45 --- - NW 45 - 55
Mt. Baker Direction - Speed
Friday Morning NW 15 - 25
Friday Afternoon W 30 - 40
Friday Night W 15 - 25
Saturday Morning WNW 10 - 20
Saturday Afternoon W 15 - 25
Saturday Evening WSW 25 - 35
Saturday Night SW 45 - 65
Washington Pass Direction - Speed
Friday Morning NW 15 - 25
Friday Afternoon WSW 30 - 40
Friday Night WSW 20 - 30
Saturday Morning W 10 - 20
Saturday Afternoon W 10 - 20
Saturday Evening WSW 40 - 50
Saturday Night WSW 50 - 60
Stevens and Snoqualmie Pass Direction - Speed
Friday Morning NW 20 - 30
Friday Afternoon W 45 - 60
Friday Night WSW 30 - 40
Saturday Morning NW 20 - 30
Saturday Afternoon NW 25 - 35
Saturday Evening W 35 - 45
Saturday Night WSW 60 - 70
Mt. Rainier Direction - Speed
Friday Morning --- -
Friday Afternoon --- -
Friday Night --- -
Saturday Morning --- -
Saturday Afternoon --- -
Saturday Evening --- -
Saturday Night --- -
Mt. Hood Direction - Speed
Friday Morning NNW 20 - 30
Friday Afternoon NW 45 - 60
Friday Night W 40 - 50
Saturday Morning NW 40 - 50
Saturday Afternoon WNW 35 - 45
Saturday Evening NW 45 - 55
Saturday Night W 55 - 65

Directions above indicate the direction the wind blows from on the 16-point cardinal scale. These winds indicate "free" winds, or those winds in the atmosphere not influenced by terrain. Topographical effects may produce greater or lower wind speeds in certain locations as well as significant variations in direction.

Jump to: Weather Forecast I Snow/Freezing Level I Precipitation I Free Winds 5k I Free Winds 9k

Previous forecast from Feb 22, 2018

The NWAC program is administered by the USDA-Forest Service and operates from the National Weather Service Forecast Office in Seattle. NWAC services are made possible by important collaboration and support from a wide variety of federal, state and private cooperators.