Issued: 2:50 PM PST Friday, January 26, 2018
by Dennis D'Amico

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

Weather Synopsis for Friday & Tuesday

Cool snow levels with moist westerly flow aloft will help to continue to squeeze decent amounts of snowfall out of what is otherwise light to occasionally moderate showers in this pattern. Locally heavier showers have been seen from Snoqualmie Pass and south today with showers training in a SW-NE fashion. Showers and cloud cover should quickly decrease further east of the Cascade crest.

A fast moving low pressure system will curl off of Vancouver Island Friday night. Warm frontal precipitation will quickly move over the area Friday night with a strong occluded front passing through the Cascades mid morning and lifting NE late morning. Moderate snow should quickly turn to scattered showers by late morning with broken skies. in the south and central Cascades, snow levels will take a quick bump into the 3000-4000 ft range by late morning but should not rise further. Post-frontal westerlies will mix down stronger winds aloft in stronger gusts on Saturday. The north Cascades will see a delayed bump in snow levels and hang onto moderate showers into the afternoon as the surface low tracks into southern B.C.  

Showers should taper off Saturday evening, but a strong warm front with a deeper moisture tap will spread generally light precipitation over the area once again Saturday night. A slow warming trend will take place overnight, most pronounced in the Mt. Hood region.  

Weather Forecast

Olympics
Friday Mostly cloudy with light snow showers.
Friday Night Cloudy with scattered light snow showers in the evening becoming light to moderate snow after midnight. Increasing winds.
Saturday Light to moderate snow early becoming partly to mostly cloudy with scattered light rain and snow showers mid-morning. Slight warming trend. Windy.
Washington Cascades near and west of the Crest including Stevens, Snoqualmie and White Passes
Friday Cloudy with light to occasionally moderate snow showers, heaviest Snoqulamie Pass and south. Moderate crest-level winds central and south Cascades.
Friday Night Cloudy with scattered light snow showers in the evening becoming light snow after midnight except moderate Snoqualmie Pass and south. Increasing winds.
Saturday Moderate snow early becoming mostly cloudy with scattered light rain and snow showers mid-late morning. Showers occasionally moderate Mt. Baker area in the afternoon. Slight warming trend late morning onward. Windy.
East Slopes of the Washington Cascades
Friday Cloudy with light snow showers near the crest, decreasing clouds and showers further east . Moderate crest-level winds central and south Cascades.
Friday Night Mostly cloudy with isolated light snow showers in the evening becoming light snow after midnight. Increasing winds.
Saturday Light to moderate snow, becoming mostly cloudy with scattered light rain and snow showers mid-day. Showers occasionally moderate northeast Cascades. Windy.
Mt. Hood
Friday Cloudy with scattered light snow showers. Windy.
Friday Night Cloudy with scattered light snow showers in the evening becoming moderate snow after midnight. Increasing winds.
Saturday Moderate snow early becoming mostly cloudy with scattered light rain and snow showers mid morning. Slight warming trend late morning onward. Very windy.

Snow/Freezing Level (ft)

Hurricane Ridge Mt. Baker Washington Pass Leavenworth Stevens Pass Snoqualmie Pass Mt. Rainier, Crystal & White Pass Mt. Hood
Friday Afternoon Snow Level 1500' 1500' 1500' ' ' 1500' ' 2500'
Friday Night Snow Level * 3000' 1000' 500' ' ' 1500' ' 3000'
Saturday Morning Snow Level 4000' 2000' 1500' ' ' 3500' ' 4500'
Saturday Afternoon Snow Level 3500' 3500' 3500' ' ' 3000' ' 4500'
Hurricane Ridge Elevation
Friday Afternoon Snow Level
1500'
Friday Night Snow Level
3000'
(Easterly Flow *)
Saturday Morning Snow Level
4000'
Saturday Afternoon Snow Level
3500'
Saturday Night Snow Level
4000'
Mt. Baker Elevation
Friday Afternoon Snow Level
1500'
Friday Night Snow Level
1000'
(Easterly Flow *)
Saturday Morning Snow Level
2000'
Saturday Afternoon Snow Level
3500'
Saturday Night Snow Level
2500'
Washington Pass Elevation
Friday Afternoon Snow Level
1500'
Friday Night Snow Level
500'
(Easterly Flow *)
Saturday Morning Snow Level
1500'
Saturday Afternoon Snow Level
3500'
Saturday Night Snow Level
2000'
Leavenworth Elevation
Friday Afternoon Snow Level
'
Friday Night Snow Level
'
(Easterly Flow *)
Saturday Morning Snow Level
'
Saturday Afternoon Snow Level
'
Saturday Night Snow Level
'
Stevens Pass Elevation
Friday Afternoon Snow Level
'
Friday Night Snow Level
'
(Easterly Flow *)
Saturday Morning Snow Level
'
Saturday Afternoon Snow Level
'
Saturday Night Snow Level
'
Snoqualmie Pass Elevation
Friday Afternoon Snow Level
1500'
Friday Night Snow Level
1500'
(Easterly Flow *)
Saturday Morning Snow Level
3500'
Saturday Afternoon Snow Level
3000'
Saturday Night Snow Level
2500'
Mt. Rainier & Crystal Elevation
Friday Afternoon Snow Level
'
Friday Night Snow Level
'
(Easterly Flow *)
Saturday Morning Snow Level
'
Saturday Afternoon Snow Level
'
Saturday Night Snow Level
'
Mt. Hood Elevation
Friday Afternoon Snow Level
2500'
Friday Night Snow Level
3000'
(Easterly Flow *)
Saturday Morning Snow Level
4500'
Saturday Afternoon Snow Level
4500'
Saturday Night Snow Level
6500'

* 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

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

Free Winds at 5000' (mph)

Hurricane Ridge Mt. Baker Stevens to Snoqualmie Pass Mt. Rainier Mt. Hood
Friday Afternoon SW 5 - 15 SW 5 - 15 SW 10 - 20 --- - SW 15 - 25
Friday Night SE 15 - 25 SE 10 - 20 ESE 15 - 25 --- - SW 15 - 30
Saturday Morning SW 25 - 35 S 15 - 30 SW 25 - 45 --- - WSW 35 - 50
Saturday Afternoon SW 15 - 25 SW 15 - 30 SW 25 - 35 --- - WSW 30 - 40
Hurricane Ridge Elevation
Friday Afternoon SW 5 - 15
Friday Night SE 15 - 25
Saturday Morning SW 25 - 35
Saturday Afternoon SW 15 - 25
Saturday Night S 10 - 20
Mt. Baker Elevation
Friday Afternoon SW 5 - 15
Friday Night SE 10 - 20
Saturday Morning S 15 - 30
Saturday Afternoon SW 15 - 30
Saturday Night SE 5 - 15
Stevens and Snoqualmie Pass Elevation
Friday Afternoon SW 10 - 20
Friday Night ESE 15 - 25
Saturday Morning SW 25 - 45
Saturday Afternoon SW 25 - 35
Saturday Night SW 15 - 25
Mt. Rainier Elevation
Friday Afternoon --- -
Friday Night --- -
Saturday Morning --- -
Saturday Afternoon --- -
Saturday Night --- -
Mt. Hood Elevation
Friday Afternoon SW 15 - 25
Friday Night SW 15 - 30
Saturday Morning WSW 35 - 50
Saturday Afternoon WSW 30 - 40
Saturday Night SW 25 - 35
Hurricane Ridge Direction - Speed
Friday Afternoon SW 5 - 15
Friday Night SE 15 - 25
Saturday Morning SW 25 - 35
Saturday Afternoon SW 15 - 25
Saturday Night S 10 - 20
Mt. Baker Direction - Speed
Friday Afternoon SW 5 - 15
Friday Night SE 10 - 20
Saturday Morning S 15 - 30
Saturday Afternoon SW 15 - 30
Saturday Night SE 5 - 15
Stevens and Snoqualmie Pass Direction - Speed
Friday Afternoon SW 10 - 20
Friday Night ESE 15 - 25
Saturday Morning SW 25 - 45
Saturday Afternoon SW 25 - 35
Saturday Night SW 15 - 25
Mt. Rainier Direction - Speed
Friday Afternoon --- -
Friday Night --- -
Saturday Morning --- -
Saturday Afternoon --- -
Saturday Night --- -
Mt. Hood Direction - Speed
Friday Afternoon SW 15 - 25
Friday Night SW 15 - 30
Saturday Morning WSW 35 - 50
Saturday Afternoon WSW 30 - 40
Saturday Night SW 25 - 35

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

Extended Weather Synopsis for Tuesday night through Tuesday

Warm frontal moisture will quickly push from south to north across the area Sunday morning, delivering a quick but moderate shot of precipitation. Snow will change to rain for west slopes of the Cascades in the morning, with cooler snow levels holding on through the afternoon for Stevens Pass and the east slopes of the Cascades. Despite the warmth, precipitation should quickly end for the south Washington Cascades and Mt. Hood area in the morning with some possible afternoon clearing as a strong upper level ridge shunts the moisture axis north. Precipitation will taper off more slowly for the central Cascades Sunday and stay trained on the NW Cascades in particular. 

The frontal boundary will shift further north into southern B.C. Sunday night, and start to sag back south sometime later Monday afternoon and Monday night. As the front sags south heavier precipitation and a cooling trend will work back across the Cascades. An upper level trough in much cooler WNW flow aloft will bring us back to a snowy and showery pattern on Tuesday. 

Extended Weather

Olympics, Washington Cascades and Mt. Hood Area
Sunday Light to moderate rain and snow all day for the north Cascades, heaviest Baker area. Light to moderate rain snow in the morning becoming periods of light rain and snow Olympics and central Cascades and with partial clearing south Washington Cascades and Mt. Hood in the afternoon. Warming trend. Monday Light to moderate rain and snow increasing during the afternoon and night from north to south. Slow cooling trend. Tuesday Light to occasionally moderate rain and snow showers. Cooler. Sunday Night Light rain north Cascades, cloudy central Cascades, and partly to mostly cloudy south Cascades. Mild.

Extended Snow/Freezing Levels

Mt. Baker Snoqualmie Pass Mt. Hood Easterly Flow *
Sunday Morning Snow Level 4000' - 5000' 4500' - 5500' 6000' - 7000' *
Sunday Night Snow Level 6000' - 7000' 6500' - 7500' 9500' - 10500'
Monday Snow Level 6000' - 7000' 6500' - 7500' 9000' - 10000'
Monday Night Snow Level 3500' - 4500' 4000' - 5000' 6000' - 7000'
Tuesday Snow Level 2500' - 3500' 2500' - 3500' 3000' - 4000'
Mt. Baker Elevation
Sunday Morning Snow Level
4000' - 5000'
(Easterly Flow *)
Sunday Night Snow Level
6000' - 7000'
Monday Snow Level
6000' - 7000'
Monday Night Snow Level
3500' - 4500'
Tuesday Snow Level
2500' - 3500'
Sunday Afternoon Snow Level
5500' - 6500'
Snoqualmie Pass Elevation
Sunday Morning Snow Level
4500' - 5500'
(Easterly Flow *)
Sunday Night Snow Level
6500' - 7500'
Monday Snow Level
6500' - 7500'
Monday Night Snow Level
4000' - 5000'
Tuesday Snow Level
2500' - 3500'
Sunday Afternoon Snow Level
6000' - 7000'
Mt. Hood Elevation
Sunday Morning Snow Level
6000' - 7000'
(Easterly Flow *)
Sunday Night Snow Level
9500' - 10500'
Monday Snow Level
9000' - 10000'
Monday Night Snow Level
6000' - 7000'
Tuesday Snow Level
3000' - 4000'
Sunday Afternoon Snow Level
7500' - 8500'

* 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.

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

Previous forecast from Jan 26, 2018

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