Issued: 2:05 PM PST Friday, November 18, 2016
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 & Friday

After a brief dry spell (about 24 hours!) the next Pacific frontal system will spread light precipitation over the area tonight. Moderate east winds at crest level for the centralwest/southwest Washington Cascades and at Snoqualmie Pass should ease tonight as the front washes out over the area. Cloud bases will continue to slowly lower through the afternoon and tonight. 

The frontal system will split with the main energy going into northern California on Saturday. A moderately cool air mass will be over the region for the weekend as a stacked low pressure system slowly meanders toward Vancouver Island. Timing the shower activity this weekend will be difficult to pin down, but with southerly flow locally higher precipitation amounts are favored for the volcanoes. The snow level will edge upwards over the weekend as easterly flow eases and milder Pacific air works inland. 

Weather Forecast

Washington Cascades near and west of the crest including Stevens, Snoqualmie, and White Passes
Friday Afternoon

Cloudy. Chance for a few sprinkles. Moderate east winds Crystal area/Snoqualmie Pass. 

Friday Night

Periods of light rain and snow increasing after midnight. 

Olympics
Friday Afternoon

Cloudy. Chance for a few sprinkles.

Friday Night

Light rain and snow increasing after midnight.  Slight warming trend. 

East slopes of the Washington Cascades
Friday Afternoon

Cloudy. Chance for a few sprinkles near the crest. 

Friday Night

Periods of light rain and snow increasing after midnight. 

Mt. Hood Area
Friday Afternoon

Cloudy. Chance for a few sprinkles. 

Friday Night

Periods of light rain and snow increasing after midnight. 

Snow/Freezing Level (ft)

Hurricane Ridge Mt. Baker Washington Pass Leavenworth Stevens Pass Snoqualmie Pass Mt. Rainier, Crystal & White Pass Mt. Hood
Friday Afternoon - Saturday Morning Snow Level * 4000' 3500' 2500' ' ' 3000' ' 4000'
Saturday Afternoon Snow Level * 5500' 4500' 3500' ' ' 4000' ' 6000'
Hurricane Ridge Elevation
Friday Afternoon - Saturday Morning Snow Level
4000'
(Easterly Flow *)
Saturday Afternoon Snow Level
5500'
(Easterly Flow *)
Saturday Night Snow Level
5000'
(Easterly Flow *)
Mt. Baker Elevation
Friday Afternoon - Saturday Morning Snow Level
3500'
(Easterly Flow *)
Saturday Afternoon Snow Level
4500'
(Easterly Flow *)
Saturday Night Snow Level
4500'
(Easterly Flow *)
Washington Pass Elevation
Friday Afternoon - Saturday Morning Snow Level
2500'
(Easterly Flow *)
Saturday Afternoon Snow Level
3500'
(Easterly Flow *)
Saturday Night Snow Level
4000'
(Easterly Flow *)
Leavenworth Elevation
Friday Afternoon - Saturday Morning Snow Level
'
(Easterly Flow *)
Saturday Afternoon Snow Level
'
(Easterly Flow *)
Saturday Night Snow Level
'
(Easterly Flow *)
Stevens Pass Elevation
Friday Afternoon - Saturday Morning Snow Level
'
(Easterly Flow *)
Saturday Afternoon Snow Level
'
(Easterly Flow *)
Saturday Night Snow Level
'
(Easterly Flow *)
Snoqualmie Pass Elevation
Friday Afternoon - Saturday Morning Snow Level
3000'
(Easterly Flow *)
Saturday Afternoon Snow Level
4000'
(Easterly Flow *)
Saturday Night Snow Level
4500'
(Easterly Flow *)
Mt. Rainier & Crystal Elevation
Friday Afternoon - Saturday Morning Snow Level
'
(Easterly Flow *)
Saturday Afternoon Snow Level
'
(Easterly Flow *)
Saturday Night Snow Level
'
(Easterly Flow *)
Mt. Hood Elevation
Friday Afternoon - Saturday Morning Snow Level
4000'
(Easterly Flow *)
Saturday Afternoon Snow Level
6000'
(Easterly Flow *)
Saturday Night Snow Level
5500'
(Easterly Flow *)

* 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

Friday Friday
Hurricane Ridge LT 0.25 0 - 0.75
Mt Baker Ski Area LT 0.25 0 - 1.00
Washington Pass LT 0.10 0 - 0.50
Stevens Pass LT 0.25 0.25 - 0.50
Snoqualmie Pass LT 0.25 0.25 - 0.50
Mission Ridge LT 0.25 LT 0.25
Crystal Mt LT 0.25 0 - 0.50
Paradise LT 0.25 0 - 0.50
White Pass LT 0.10 LT 0.10
Mt Hood Meadows LT 0.25 LT 0.25
LT 0.25 LT 0.25

Free Winds at 5000' (mph)

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

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 S 15 - 25 S 20 - 30 SSW 15 - 25 --- - SW 25 - 35
Friday Night - Saturday Morning SW 25 - 35 S 20 - 30 SW 35 - 45 --- - SW 35 - 45
Mt. Baker Direction - Speed
Friday Afternoon S 15 - 25
Friday Night - Saturday Morning SW 25 - 35
Saturday Afternoon - Saturday Night SW 20 - 30
Washington Pass Direction - Speed
Friday Afternoon S 20 - 30
Friday Night - Saturday Morning S 20 - 30
Saturday Afternoon - Saturday Night SW 15 - 25
Stevens and Snoqualmie Pass Direction - Speed
Friday Afternoon SSW 15 - 25
Friday Night - Saturday Morning SW 35 - 45
Saturday Afternoon - Saturday Night SW 30 - 40
Mt. Rainier Direction - Speed
Friday Afternoon --- -
Friday Night - Saturday Morning --- -
Saturday Afternoon - Saturday Night --- -
Mt. Hood Direction - Speed
Friday Afternoon SW 25 - 35
Friday Night - Saturday Morning SW 35 - 45
Saturday Afternoon - Saturday Night SW 35 - 50

Extended Weather Synopsis for Friday night through Friday

The longwave trough will shift over the area Monday with lingering showers.  A shortwave ridge will quickly build offshore and pass east of the Cascades Monday night. The next splitting frontal system will be on our doorstep by Tuesday afternoon. An active pattern looks to continue into the upcoming holiday weekend. 

Extended Weather

Olympics, Washington Cascades near and west of the crest including Stevens, Snoqualmie, and White Passes
Sunday

Light to occasionally moderate rain and snow showers. Milder. 

Sunday Night - Monday

Mostly cloudy with scattered light rain and snow showers. Showers decreasing Monday afternoon. 

Monday Night - Tuesday

Mostly cloudy Monday night with increasing clouds Tuesday with light rain and snow developing in the afternoon. 

Extended Snow/Freezing Levels

Mt. Baker Snoqualmie Pass Mt. Hood Easterly Flow *
Sunday - Monday Morning Snow Level 4000' - 5000' 4000' - 5000' 4500' - 5500'
Monday Afternoon - Monday Night Snow Level 3500' - 4500' 3500' - 4500' 3500' - 4500'
Mt. Baker Elevation
Sunday - Monday Morning Snow Level
4000' - 5000'
Monday Afternoon - Monday Night Snow Level
3500' - 4500'
Tuesday Snow Level
3000' - 4000'
Snoqualmie Pass Elevation
Sunday - Monday Morning Snow Level
4000' - 5000'
Monday Afternoon - Monday Night Snow Level
3500' - 4500'
Tuesday Snow Level
3000' - 4000'
Mt. Hood Elevation
Sunday - Monday Morning Snow Level
4500' - 5500'
Monday Afternoon - Monday Night Snow Level
3500' - 4500'
Tuesday Snow Level
4500' - 5500'

* 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 Nov 16, 2016

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.

We are now issuing Mountain Weather Forecasts at 130 pm, 7 days a week, until we begin our usual forecast schedule. We are also issuing Weekend Snow and Avalanche Outlooks at 6 pm on Thursday until we begin our usual forecast schedule.