Issued: 7:12 AM PST Sunday, November 29, 2020
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 Sunday & Thursday

An upper level ridge will provide more dry day before a frontal system arrives late tonight. High clouds will affect many the Olympics and periodically the northwest Cascades as the system inches closer.  Winds are a bit stronger than expected this morning again for the Olympics and northwest Cascades, and will increase further this afternoon. Easterly flow through the Cascade Passes will set up temperature inversions, with the warmest and above freezing air likely to be found above 5000'. There will also be a stiff E-SE breeze for most of the day. Colder air will stay lodged in place for the east slopes of the Cascades with little warming expected. 

The frontal system now looks like it should pass through the Cascades around 5- 6 am on Monday morning. Snow levels will quickly drop with the onset of precipitation to 3000 ft or lower across the region. The front will bring a moderate shot of snow to the region with post-frontal snow showers helping to accumulate 6-10" across the west slopes of the Cascades, Mt. Hood and the Olympics and lower amounts along the east slopes of the Cascades through Monday afternoon. The bigger story will likely be the wind, both ahead of the front with strong to extreme southerlies for Hurricane Ridge and Mt Baker and behind the front with similar strength westerlies for most areas. 

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
Sunday Morning Freezing Level * 7500' 6000' 2500' 2500' 3500' 5500' 7500' 8000'
Sunday Afternoon Freezing Level * 7000' 6500' 3500' 4000' 5500' 7000' 8000' 8500'
Sunday Evening Freezing Level * 6000' 5500' 3500' 3500' 4000' 5500' 6500' 6500'
Sunday Night Snow Level * 4500' 3000' 2000' 2500' 2500' 3000' 3500' 4000'
Monday Morning Snow Level 3000' 2500' 2000' 2000' 2500' 2500' 3000' 3000'
Hurricane Ridge Elevation
Sunday Morning Freezing Level
7500'
(Easterly Flow *)
Sunday Afternoon Freezing Level
7000'
(Easterly Flow *)
Sunday Evening Freezing Level
6000'
(Easterly Flow *)
Sunday Night Snow Level
4500'
(Easterly Flow *)
Monday Morning Snow Level
3000'
Monday Afternoon Snow Level
2000'
Mt. Baker Elevation
Sunday Morning Freezing Level
6000'
(Easterly Flow *)
Sunday Afternoon Freezing Level
6500'
(Easterly Flow *)
Sunday Evening Freezing Level
5500'
(Easterly Flow *)
Sunday Night Snow Level
3000'
(Easterly Flow *)
Monday Morning Snow Level
2500'
Monday Afternoon Snow Level
2000'
Washington Pass Elevation
Sunday Morning Freezing Level
2500'
(Easterly Flow *)
Sunday Afternoon Freezing Level
3500'
(Easterly Flow *)
Sunday Evening Freezing Level
3500'
(Easterly Flow *)
Sunday Night Snow Level
2000'
(Easterly Flow *)
Monday Morning Snow Level
2000'
Monday Afternoon Snow Level
1500'
Leavenworth Elevation
Sunday Morning Freezing Level
2500'
(Easterly Flow *)
Sunday Afternoon Freezing Level
4000'
(Easterly Flow *)
Sunday Evening Freezing Level
3500'
(Easterly Flow *)
Sunday Night Snow Level
2500'
(Easterly Flow *)
Monday Morning Snow Level
2000'
Monday Afternoon Snow Level
1500'
Stevens Pass Elevation
Sunday Morning Freezing Level
3500'
(Easterly Flow *)
Sunday Afternoon Freezing Level
5500'
(Easterly Flow *)
Sunday Evening Freezing Level
4000'
(Easterly Flow *)
Sunday Night Snow Level
2500'
(Easterly Flow *)
Monday Morning Snow Level
2500'
Monday Afternoon Snow Level
2000'
Snoqualmie Pass Elevation
Sunday Morning Freezing Level
5500'
(Easterly Flow *)
Sunday Afternoon Freezing Level
7000'
(Easterly Flow *)
Sunday Evening Freezing Level
5500'
(Easterly Flow *)
Sunday Night Snow Level
3000'
(Easterly Flow *)
Monday Morning Snow Level
2500'
Monday Afternoon Snow Level
2000'
Mt. Rainier & Crystal Elevation
Sunday Morning Freezing Level
7500'
(Easterly Flow *)
Sunday Afternoon Freezing Level
8000'
(Easterly Flow *)
Sunday Evening Freezing Level
6500'
(Easterly Flow *)
Sunday Night Snow Level
3500'
(Easterly Flow *)
Monday Morning Snow Level
3000'
Monday Afternoon Snow Level
2000'
Mt. Hood Elevation
Sunday Morning Freezing Level
8000'
(Easterly Flow *)
Sunday Afternoon Freezing Level
8500'
(Easterly Flow *)
Sunday Evening Freezing Level
6500'
(Easterly Flow *)
Sunday Night Snow Level
4000'
(Easterly Flow *)
Monday Morning Snow Level
3000'
Monday Afternoon Snow Level
2500'

* 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

Sunday Sunday Night Thursday
4 am - 4 pm 4 pm - 4 am 4 am - 4 pm
Hurricane Ridge 0 0.25 - 0.50 LT 0.25
Mt Baker Ski Area 0 0.25 - 0.50 0.50 - 0.75
Washington Pass 0 LT 0.10 0.25 - 0.50
Leavenworth 0 0 LT 0.25
Stevens Pass 0 LT 0.10 0.50 - 0.75
Snoqualmie Pass 0 LT 0.25 0.50 - 0.75
Mission Ridge 0 0 LT 0.25
Crystal Mt 0 LT 0.25 0.50
Paradise 0 0.25 - 0.50 0.75
White Pass 0 LT 0.10 0.50 - 0.75
Mt Hood Meadows 0 LT 0.10 0.75 -1.00
0 LT 0.10 0.75 -1.00
Hurricane Ridge Precipitation Forecast
Sunday 0
Sunday Night 0.25 - 0.50
Thursday LT 0.25
Mt Baker Ski Area Precipitation Forecast
Sunday 0
Sunday Night 0.25 - 0.50
Thursday 0.50 - 0.75
Washington Pass Precipitation Forecast
Sunday 0
Sunday Night LT 0.10
Thursday 0.25 - 0.50
Leavenworth Precipitation Forecast
Sunday 0
Sunday Night 0
Thursday LT 0.25
Stevens Pass Precipitation Forecast
Sunday 0
Sunday Night LT 0.10
Thursday 0.50 - 0.75
Snoqualmie Pass Precipitation Forecast
Sunday 0
Sunday Night LT 0.25
Thursday 0.50 - 0.75
Mission Ridge Precipitation Forecast
Sunday 0
Sunday Night 0
Thursday LT 0.25
Crystal Mt Precipitation Forecast
Sunday 0
Sunday Night LT 0.25
Thursday 0.50
Paradise Precipitation Forecast
Sunday 0
Sunday Night 0.25 - 0.50
Thursday 0.75
White Pass Precipitation Forecast
Sunday 0
Sunday Night LT 0.10
Thursday 0.50 - 0.75
Mt Hood Meadows Precipitation Forecast
Sunday 0
Sunday Night LT 0.10
Thursday 0.75 -1.00
Timberline Precipitation Forecast
Sunday 0
Sunday Night LT 0.10
Thursday 0.75 -1.00

Free Winds at 5000' (mph)

Hurricane Ridge Mt. Baker Stevens to Snoqualmie Pass Mt. Rainier Mt. Hood
Sunday Morning S 10 - 20 S 10 - 20 ESE 10 - 20 S 5 - 15 SE 5 - 15
Sunday Afternoon S 15 - 25 S 15 - 25 ESE 10 - 20 S 5 - 15 S 5 - 15
Sunday Evening S 20 - 30 S 20 - 30 ESE 15 - 25 S 10 - 20 S 5 - 15
Sunday Night S 35 - 50 S 35 - 50 SE 15 - 25 S 20 - 30 SW 20 - 30
Monday Morning WSW 30 - 40 WSW 25 - 35 WSW 30 - 40 WSW 30 - 40 WSW 30 - 40
Hurricane Ridge Elevation
Sunday Morning S 10 - 20
Sunday Afternoon S 15 - 25
Sunday Evening S 20 - 30
Sunday Night S 35 - 50
Monday Morning WSW 30 - 40
Monday Afternoon W 25 - 35
Mt. Baker Elevation
Sunday Morning S 10 - 20
Sunday Afternoon S 15 - 25
Sunday Evening S 20 - 30
Sunday Night S 35 - 50
Monday Morning WSW 25 - 35
Monday Afternoon W 15 - 25
Stevens and Snoqualmie Pass Elevation
Sunday Morning ESE 10 - 20
Sunday Afternoon ESE 10 - 20
Sunday Evening ESE 15 - 25
Sunday Night SE 15 - 25
Monday Morning WSW 30 - 40
Monday Afternoon W 25 - 35
Mt. Rainier Elevation
Sunday Morning S 5 - 15
Sunday Afternoon S 5 - 15
Sunday Evening S 10 - 20
Sunday Night S 20 - 30
Monday Morning WSW 30 - 40
Monday Afternoon W 20 - 30
Mt. Hood Elevation
Sunday Morning SE 5 - 15
Sunday Afternoon S 5 - 15
Sunday Evening S 5 - 15
Sunday Night SW 20 - 30
Monday Morning WSW 30 - 40
Monday Afternoon W 25 - 35
Hurricane Ridge Direction - Speed
Sunday Morning S 10 - 20
Sunday Afternoon S 15 - 25
Sunday Evening S 20 - 30
Sunday Night S 35 - 50
Monday Morning WSW 30 - 40
Monday Afternoon W 25 - 35
Mt. Baker Direction - Speed
Sunday Morning S 10 - 20
Sunday Afternoon S 15 - 25
Sunday Evening S 20 - 30
Sunday Night S 35 - 50
Monday Morning WSW 25 - 35
Monday Afternoon W 15 - 25
Stevens and Snoqualmie Pass Direction - Speed
Sunday Morning ESE 10 - 20
Sunday Afternoon ESE 10 - 20
Sunday Evening ESE 15 - 25
Sunday Night SE 15 - 25
Monday Morning WSW 30 - 40
Monday Afternoon W 25 - 35
Mt. Rainier Direction - Speed
Sunday Morning S 5 - 15
Sunday Afternoon S 5 - 15
Sunday Evening S 10 - 20
Sunday Night S 20 - 30
Monday Morning WSW 30 - 40
Monday Afternoon W 20 - 30
Mt. Hood Direction - Speed
Sunday Morning SE 5 - 15
Sunday Afternoon S 5 - 15
Sunday Evening S 5 - 15
Sunday Night SW 20 - 30
Monday Morning WSW 30 - 40
Monday Afternoon W 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
Sunday Morning SW 20 - 30 SW 20 - 30 SW 15 - 25 SW 15 - 25 S 10 - 20
Sunday Afternoon SW 30 - 40 SW 30 - 40 SW 15 - 25 SW 15 - 25 SW 15 - 25
Sunday Evening SW 35 - 45 SW 25 - 35 SW 20 - 30 SW 20 - 30 SW 20 - 30
Sunday Night SSW 50 - 60 SW 30 - 40 SW 40 - 60 SW 40 - 60 SW 45 - 60
Monday Morning SW 30 - 40 SW 35 - 45 WSW 50 - 60 W 50 - 60 W 55 - 65
Mt. Baker Direction - Speed
Sunday Morning SW 20 - 30
Sunday Afternoon SW 30 - 40
Sunday Evening SW 35 - 45
Sunday Night SSW 50 - 60
Monday Morning SW 30 - 40
Monday Afternoon W 30 - 40
Washington Pass Direction - Speed
Sunday Morning SW 20 - 30
Sunday Afternoon SW 30 - 40
Sunday Evening SW 25 - 35
Sunday Night SW 30 - 40
Monday Morning SW 35 - 45
Monday Afternoon W 40 - 50
Stevens and Snoqualmie Pass Direction - Speed
Sunday Morning SW 15 - 25
Sunday Afternoon SW 15 - 25
Sunday Evening SW 20 - 30
Sunday Night SW 40 - 60
Monday Morning WSW 50 - 60
Monday Afternoon WNW 40 - 50
Mt. Rainier Direction - Speed
Sunday Morning SW 15 - 25
Sunday Afternoon SW 15 - 25
Sunday Evening SW 20 - 30
Sunday Night SW 40 - 60
Monday Morning W 50 - 60
Monday Afternoon WNW 40 - 50
Mt. Hood Direction - Speed
Sunday Morning S 10 - 20
Sunday Afternoon SW 15 - 25
Sunday Evening SW 20 - 30
Sunday Night SW 45 - 60
Monday Morning W 55 - 65
Monday Afternoon WNW 50 - 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.

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

Previous forecast from Nov 28, 2020

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