Issued: 6:46 AM PST Friday, December 28, 2018
by Robert Hahn

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

Weather Synopsis for Friday & Friday

A warm front draped off the coast of Washington and British Columbia will spread increasing moisture into the region Friday before moving eastward across the region Friday evening. With cold air in place, the warm front will bring increasing mountain snows, followed by a transition to rain in many locations (including Snoqualmie, Stevens, and White passes) as flow switches westerly before midnight and snow levels rise to Cascade Crest level. Expect 3-6" of snow at the Cascade Passes before the transition to rain.

The Pacific Northwest will remain in the Warm sector with lighter precipitation Saturday morning before a cold frontal rainband arrives from the NW during the afternoon hours and progresses SE through the evening hours bringing moderate to heavy rain to many areas on a cooling trend. Snoqualmie Pass should expect a transition back to snow around 10 PM, shortly after the frontal passage. Winds will increase through the day on Saturday, peaking with the frontal passage in the early evening hours in the moderate to strong range. 

Decreasing light snow showers will continue later Saturday night and Sunday on a moist N-NW flow with low snow levels winds becoming light to moderate.

Overall, the storm will bring the most moisture to the Mt. Rainier and central Washington Cascades areas, with more than 2/3 of the water falling as rain rather than snow at pass level.

Weather Forecast

Hurricane Ridge
Mt. Baker
Washington Pass and Leavenworth
Stevens and Snoqualmie Pass
Mt. Rainier, Crystal and White Pass
Mt. Hood

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 3500' 1000' 500' 500' 1000' 1500' 2000' 2000'
Friday Afternoon Snow Level * 5000' 2000' 2500' 2000' 3000' 2500' 3000' 3000'
Friday Evening Snow Level * 7500' 4000' 3000' 3000' 3000' 4000' 4000' 4500'
Friday Night Snow Level 8000' 6000' 5500' 6000' 6000' 6500' 7000' 7500'
Saturday Morning Snow Level 7500' 6000' 5000' 7000' 6000' 6000' 6000' 7500'
Hurricane Ridge Elevation
Friday Morning Snow Level
3500'
Friday Afternoon Snow Level
5000'
(Easterly Flow *)
Friday Evening Snow Level
7500'
(Easterly Flow *)
Friday Night Snow Level
8000'
Saturday Morning Snow Level
7500'
Saturday Afternoon Snow Level
6000'
Mt. Baker Elevation
Friday Morning Snow Level
1000'
Friday Afternoon Snow Level
2000'
(Easterly Flow *)
Friday Evening Snow Level
4000'
(Easterly Flow *)
Friday Night Snow Level
6000'
Saturday Morning Snow Level
6000'
Saturday Afternoon Snow Level
5000'
Washington Pass Elevation
Friday Morning Snow Level
500'
Friday Afternoon Snow Level
2500'
(Easterly Flow *)
Friday Evening Snow Level
3000'
(Easterly Flow *)
Friday Night Snow Level
5500'
Saturday Morning Snow Level
5000'
Saturday Afternoon Snow Level
5000'
Leavenworth Elevation
Friday Morning Snow Level
500'
Friday Afternoon Snow Level
2000'
(Easterly Flow *)
Friday Evening Snow Level
3000'
(Easterly Flow *)
Friday Night Snow Level
6000'
Saturday Morning Snow Level
7000'
Saturday Afternoon Snow Level
6000'
Stevens Pass Elevation
Friday Morning Snow Level
1000'
Friday Afternoon Snow Level
3000'
(Easterly Flow *)
Friday Evening Snow Level
3000'
(Easterly Flow *)
Friday Night Snow Level
6000'
Saturday Morning Snow Level
6000'
Saturday Afternoon Snow Level
5000'
Snoqualmie Pass Elevation
Friday Morning Snow Level
1500'
Friday Afternoon Snow Level
2500'
(Easterly Flow *)
Friday Evening Snow Level
4000'
(Easterly Flow *)
Friday Night Snow Level
6500'
Saturday Morning Snow Level
6000'
Saturday Afternoon Snow Level
5000'
Mt. Rainier & Crystal Elevation
Friday Morning Snow Level
2000'
Friday Afternoon Snow Level
3000'
(Easterly Flow *)
Friday Evening Snow Level
4000'
(Easterly Flow *)
Friday Night Snow Level
7000'
Saturday Morning Snow Level
6000'
Saturday Afternoon Snow Level
5000'
Mt. Hood Elevation
Friday Morning Snow Level
2000'
Friday Afternoon Snow Level
3000'
(Easterly Flow *)
Friday Evening Snow Level
4500'
(Easterly Flow *)
Friday Night Snow Level
7500'
Saturday Morning Snow Level
7500'
Saturday Afternoon Snow Level
5000'

* 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 Night Friday
4 am - 4 pm 4 pm - 4 am 4 am - 4 pm
Hurricane Ridge 0.25 - 0.50 0.25 0.50
Mt Baker Ski Area 0.25 - 0.50 0.50 0.75
Washington Pass LT 0.25 0.25 0.25 - 0.50
Leavenworth LT 0.10 LT 0.25 LT 0.25
Stevens Pass 0.25 0.75 0.50
Snoqualmie Pass 0.50 1.50 0.75
Mission Ridge LT 0.25 LT 0.25 LT 0.25
Crystal Mt 0.25 0.25 - 0.50 LT 0.25
Paradise 0.50 1.50 - 2.00 1.00
White Pass 0.25 0.50 - 0.75 0.25 - 0.50
Mt Hood Meadows LT 0.25 0.75 0.50
LT 0.25 0.75 0.50
Hurricane Ridge Precipitation Forecast
Friday 0.25 - 0.50
Friday Night 0.25
Friday 0.50
Mt Baker Ski Area Precipitation Forecast
Friday 0.25 - 0.50
Friday Night 0.50
Friday 0.75
Washington Pass Precipitation Forecast
Friday LT 0.25
Friday Night 0.25
Friday 0.25 - 0.50
Leavenworth Precipitation Forecast
Friday LT 0.10
Friday Night LT 0.25
Friday LT 0.25
Stevens Pass Precipitation Forecast
Friday 0.25
Friday Night 0.75
Friday 0.50
Snoqualmie Pass Precipitation Forecast
Friday 0.50
Friday Night 1.50
Friday 0.75
Mission Ridge Precipitation Forecast
Friday LT 0.25
Friday Night LT 0.25
Friday LT 0.25
Crystal Mt Precipitation Forecast
Friday 0.25
Friday Night 0.25 - 0.50
Friday LT 0.25
Paradise Precipitation Forecast
Friday 0.50
Friday Night 1.50 - 2.00
Friday 1.00
White Pass Precipitation Forecast
Friday 0.25
Friday Night 0.50 - 0.75
Friday 0.25 - 0.50
Mt Hood Meadows Precipitation Forecast
Friday LT 0.25
Friday Night 0.75
Friday 0.50
Timberline Precipitation Forecast
Friday LT 0.25
Friday Night 0.75
Friday 0.50

Free Winds at 5000' (mph)

Hurricane Ridge Mt. Baker Stevens to Snoqualmie Pass Mt. Rainier Mt. Hood
Friday Morning SW 5 - 15 SSW 5 - 15 WSW 5 - 15 WSW 5 - 15 W 10 - 20
Friday Afternoon SSW 15 - 25 SSW 10 - 20 WSW 10 - 20 WSW 10 - 20 WSW 10 - 20
Friday Evening WSW 15 - 25 S 10 - 20 WSW 15 - 25 WSW 15 - 25 WSW 20 - 30
Friday Night WSW 25 - 35 SSW 25 - 35 WSW 20 - 30 WSW 20 - 30 WSW 25 - 35
Saturday Morning SW 30 - 45 SW 30 - 45 WSW 30 - 45 WSW 30 - 45 WSW 30 - 45
Hurricane Ridge Elevation
Friday Morning SW 5 - 15
Friday Afternoon SSW 15 - 25
Friday Evening WSW 15 - 25
Friday Night WSW 25 - 35
Saturday Morning SW 30 - 45
Saturday Afternoon WSW 30 - 45
Mt. Baker Elevation
Friday Morning SSW 5 - 15
Friday Afternoon SSW 10 - 20
Friday Evening S 10 - 20
Friday Night SSW 25 - 35
Saturday Morning SW 30 - 45
Saturday Afternoon SSW 30 - 45
Stevens and Snoqualmie Pass Elevation
Friday Morning WSW 5 - 15
Friday Afternoon WSW 10 - 20
Friday Evening WSW 15 - 25
Friday Night WSW 20 - 30
Saturday Morning WSW 30 - 45
Saturday Afternoon --- 35 - 50
Mt. Rainier Elevation
Friday Morning WSW 5 - 15
Friday Afternoon WSW 10 - 20
Friday Evening WSW 15 - 25
Friday Night WSW 20 - 30
Saturday Morning WSW 30 - 45
Saturday Afternoon SW 35 - 50
Mt. Hood Elevation
Friday Morning W 10 - 20
Friday Afternoon WSW 10 - 20
Friday Evening WSW 20 - 30
Friday Night WSW 25 - 35
Saturday Morning WSW 30 - 45
Saturday Afternoon WSW 40 - 60
Hurricane Ridge Direction - Speed
Friday Morning SW 5 - 15
Friday Afternoon SSW 15 - 25
Friday Evening WSW 15 - 25
Friday Night WSW 25 - 35
Saturday Morning SW 30 - 45
Saturday Afternoon WSW 30 - 45
Mt. Baker Direction - Speed
Friday Morning SSW 5 - 15
Friday Afternoon SSW 10 - 20
Friday Evening S 10 - 20
Friday Night SSW 25 - 35
Saturday Morning SW 30 - 45
Saturday Afternoon SSW 30 - 45
Stevens and Snoqualmie Pass Direction - Speed
Friday Morning WSW 5 - 15
Friday Afternoon WSW 10 - 20
Friday Evening WSW 15 - 25
Friday Night WSW 20 - 30
Saturday Morning WSW 30 - 45
Saturday Afternoon --- 35 - 50
Mt. Rainier Direction - Speed
Friday Morning WSW 5 - 15
Friday Afternoon WSW 10 - 20
Friday Evening WSW 15 - 25
Friday Night WSW 20 - 30
Saturday Morning WSW 30 - 45
Saturday Afternoon SW 35 - 50
Mt. Hood Direction - Speed
Friday Morning W 10 - 20
Friday Afternoon WSW 10 - 20
Friday Evening WSW 20 - 30
Friday Night WSW 25 - 35
Saturday Morning WSW 30 - 45
Saturday Afternoon WSW 40 - 60

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 W 15 - 25 W 15 - 25 WNW 20 - 30 NW 20 - 30 NNW 20 - 30
Friday Afternoon WSW 25 - 35 WSW 20 - 30 W 30 - 45 WSW 30 - 45 NW 30 - 45
Friday Evening W 30 - 45 W 35 - 50 W 35 - 50 WNW 40 - 60 WNW 40 - 60
Friday Night WSW 50 - 70 WSW 55 - 75 W 50 - 70 W 45 - 65 WNW 35 - 50
Saturday Morning WSW 50 - 70 WSW 60 - 80 W 55 - 75 W 60 - 80 W 40 - 60
Mt. Baker Direction - Speed
Friday Morning W 15 - 25
Friday Afternoon WSW 25 - 35
Friday Evening W 30 - 45
Friday Night WSW 50 - 70
Saturday Morning WSW 50 - 70
Saturday Afternoon SW 55 - 75
Washington Pass Direction - Speed
Friday Morning W 15 - 25
Friday Afternoon WSW 20 - 30
Friday Evening W 35 - 50
Friday Night WSW 55 - 75
Saturday Morning WSW 60 - 80
Saturday Afternoon SW 60 - 80
Stevens and Snoqualmie Pass Direction - Speed
Friday Morning WNW 20 - 30
Friday Afternoon W 30 - 45
Friday Evening W 35 - 50
Friday Night W 50 - 70
Saturday Morning W 55 - 75
Saturday Afternoon WSW 60 - 80
Mt. Rainier Direction - Speed
Friday Morning NW 20 - 30
Friday Afternoon WSW 30 - 45
Friday Evening WNW 40 - 60
Friday Night W 45 - 65
Saturday Morning W 60 - 80
Saturday Afternoon WSW 65 - 85
Mt. Hood Direction - Speed
Friday Morning NNW 20 - 30
Friday Afternoon NW 30 - 45
Friday Evening WNW 40 - 60
Friday Night WNW 35 - 50
Saturday Morning W 40 - 60
Saturday Afternoon WSW 55 - 75

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 Dec 27, 2018

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