Issued: 7:28 AM PST Wednesday, December 6, 2017
by Robert Hahn

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

Weather Synopsis for Wednesday & Friday

The story of the week is high, HIGH pressure with no end in sight at the moment. If this were July, we'd be looking at high temperatures in the mid-80's in the lowlands! In December, we have a nice inversion sitting over us with a shallow cold pool east of the Cascade crest, so don't expect record temperatures in the lowlands. Generally, free air freezing levels will be in the 10,000-12,000 ft range during the short-term forecasting period.

With continued amplification of the ridge on Wednesday and the ridge axis offshore, we'll see northerly flow aloft and moderate easterly offshore flow at the surface. During the day on Thursday, the ridge axis will slightly shift east over us with light and variable winds aloft with offshore easterly gradients peaking Thursday morning.

Weather Forecast

Olympics, Washington Cascades and Mt. Hood Area
Wednesday

Mostly sunny, with morning low clouds possible near passes and valleys.

Wednesday Night

Mostly clear, with low clouds possible near passes and valleys.

Thursday

Mostly sunny, with morning  low clouds possible near passes and valleys.

Snow/Freezing Level (ft)

Hurricane Ridge Mt. Baker Washington Pass Leavenworth Stevens Pass Snoqualmie Pass Mt. Rainier, Crystal & White Pass Mt. Hood
Wednesday Morning Freezing Level * 10000' 8000' 5000' ' ' 6000' ' 10000'
Wednesday Afternoon Snow Level * 11000' 10000' 9000' ' ' 10000' ' 11000'
Wednesday Night Snow Level * 11000' 11000' 10000' ' ' 11000' ' 11500'
Thursday Morning Snow Level * 11000' 11000' 11000' ' ' 11000' ' 11500'
Thursday Afternoon Snow Level * 11000' 11000' 11000' ' ' 11500' ' 12000'
Hurricane Ridge Elevation
Wednesday Morning Freezing Level
10000'
(Easterly Flow *)
Wednesday Afternoon Snow Level
11000'
(Easterly Flow *)
Wednesday Night Snow Level
11000'
(Easterly Flow *)
Thursday Morning Snow Level
11000'
(Easterly Flow *)
Thursday Afternoon Snow Level
11000'
(Easterly Flow *)
Thursday Night Snow Level
10000'
(Easterly Flow *)
Mt. Baker Elevation
Wednesday Morning Freezing Level
8000'
(Easterly Flow *)
Wednesday Afternoon Snow Level
10000'
(Easterly Flow *)
Wednesday Night Snow Level
11000'
(Easterly Flow *)
Thursday Morning Snow Level
11000'
(Easterly Flow *)
Thursday Afternoon Snow Level
11000'
(Easterly Flow *)
Thursday Night Snow Level
10000'
(Easterly Flow *)
Washington Pass Elevation
Wednesday Morning Freezing Level
5000'
(Easterly Flow *)
Wednesday Afternoon Snow Level
9000'
(Easterly Flow *)
Wednesday Night Snow Level
10000'
(Easterly Flow *)
Thursday Morning Snow Level
11000'
(Easterly Flow *)
Thursday Afternoon Snow Level
11000'
(Easterly Flow *)
Thursday Night Snow Level
10000'
(Easterly Flow *)
Leavenworth Elevation
Wednesday Morning Freezing Level
'
(Easterly Flow *)
Wednesday Afternoon Snow Level
'
(Easterly Flow *)
Wednesday Night Snow Level
'
(Easterly Flow *)
Thursday Morning Snow Level
'
(Easterly Flow *)
Thursday Afternoon Snow Level
'
(Easterly Flow *)
Thursday Night Snow Level
'
(Easterly Flow *)
Stevens Pass Elevation
Wednesday Morning Freezing Level
'
(Easterly Flow *)
Wednesday Afternoon Snow Level
'
(Easterly Flow *)
Wednesday Night Snow Level
'
(Easterly Flow *)
Thursday Morning Snow Level
'
(Easterly Flow *)
Thursday Afternoon Snow Level
'
(Easterly Flow *)
Thursday Night Snow Level
'
(Easterly Flow *)
Snoqualmie Pass Elevation
Wednesday Morning Freezing Level
6000'
(Easterly Flow *)
Wednesday Afternoon Snow Level
10000'
(Easterly Flow *)
Wednesday Night Snow Level
11000'
(Easterly Flow *)
Thursday Morning Snow Level
11000'
(Easterly Flow *)
Thursday Afternoon Snow Level
11500'
(Easterly Flow *)
Thursday Night Snow Level
10000'
(Easterly Flow *)
Mt. Rainier & Crystal Elevation
Wednesday Morning Freezing Level
'
(Easterly Flow *)
Wednesday Afternoon Snow Level
'
(Easterly Flow *)
Wednesday Night Snow Level
'
(Easterly Flow *)
Thursday Morning Snow Level
'
(Easterly Flow *)
Thursday Afternoon Snow Level
'
(Easterly Flow *)
Thursday Night Snow Level
'
(Easterly Flow *)
Mt. Hood Elevation
Wednesday Morning Freezing Level
10000'
(Easterly Flow *)
Wednesday Afternoon Snow Level
11000'
(Easterly Flow *)
Wednesday Night Snow Level
11500'
(Easterly Flow *)
Thursday Morning Snow Level
11500'
(Easterly Flow *)
Thursday Afternoon Snow Level
12000'
(Easterly Flow *)
Thursday Night Snow Level
10500'
(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 0.10 LT 0.10
Mt Baker Ski Area LT 0.10 LT 0.10
Washington Pass LT 0.10 LT 0.10
Stevens Pass LT 0.10 LT 0.10
Snoqualmie Pass LT 0.10 LT 0.10
Mission Ridge LT 0.10 LT 0.10
Crystal Mt LT 0.10 LT 0.10
Paradise LT 0.10 LT 0.10
White Pass LT 0.10 LT 0.10
Mt Hood Meadows LT 0.10 LT 0.10
LT 0.10 LT 0.10

Free Winds at 5000' (mph)

Hurricane Ridge Mt. Baker Stevens to Snoqualmie Pass Mt. Rainier Mt. Hood
Wednesday Morning E 10 - 20 ENE 0 - 10 E 20 - 30 --- - E 15 - 30
Wednesday Afternoon ESE 5 - 15 E 0 - 10 E 10 - 20 --- - ESE 15 - 25
Wednesday Night SE 5 - 15 E 0 - 10 ESE 10 - 20 --- - SE 15 - 25
Thursday Morning SE 5 - 15 E 0 - 10 ESE 10 - 20 --- - SE 10 - 20
Thursday Afternoon S 0 - 10 SE 0 - 10 ESE 5 - 15 --- - SE 5 - 15
Hurricane Ridge Elevation
Wednesday Morning E 10 - 20
Wednesday Afternoon ESE 5 - 15
Wednesday Night SE 5 - 15
Thursday Morning SE 5 - 15
Thursday Afternoon S 0 - 10
Thursday Night SW 0 - 10
Mt. Baker Elevation
Wednesday Morning ENE 0 - 10
Wednesday Afternoon E 0 - 10
Wednesday Night E 0 - 10
Thursday Morning E 0 - 10
Thursday Afternoon SE 0 - 10
Thursday Night SW 0 - 10
Stevens and Snoqualmie Pass Elevation
Wednesday Morning E 20 - 30
Wednesday Afternoon E 10 - 20
Wednesday Night ESE 10 - 20
Thursday Morning ESE 10 - 20
Thursday Afternoon ESE 5 - 15
Thursday Night VAR 0 - 10
Mt. Rainier Elevation
Wednesday Morning --- -
Wednesday Afternoon --- -
Wednesday Night --- -
Thursday Morning --- -
Thursday Afternoon --- -
Thursday Night --- -
Mt. Hood Elevation
Wednesday Morning E 15 - 30
Wednesday Afternoon ESE 15 - 25
Wednesday Night SE 15 - 25
Thursday Morning SE 10 - 20
Thursday Afternoon SE 5 - 15
Thursday Night SSE 5 - 15
Hurricane Ridge Direction - Speed
Wednesday Morning E 10 - 20
Wednesday Afternoon ESE 5 - 15
Wednesday Night SE 5 - 15
Thursday Morning SE 5 - 15
Thursday Afternoon S 0 - 10
Thursday Night SW 0 - 10
Mt. Baker Direction - Speed
Wednesday Morning ENE 0 - 10
Wednesday Afternoon E 0 - 10
Wednesday Night E 0 - 10
Thursday Morning E 0 - 10
Thursday Afternoon SE 0 - 10
Thursday Night SW 0 - 10
Stevens and Snoqualmie Pass Direction - Speed
Wednesday Morning E 20 - 30
Wednesday Afternoon E 10 - 20
Wednesday Night ESE 10 - 20
Thursday Morning ESE 10 - 20
Thursday Afternoon ESE 5 - 15
Thursday Night VAR 0 - 10
Mt. Rainier Direction - Speed
Wednesday Morning --- -
Wednesday Afternoon --- -
Wednesday Night --- -
Thursday Morning --- -
Thursday Afternoon --- -
Thursday Night --- -
Mt. Hood Direction - Speed
Wednesday Morning E 15 - 30
Wednesday Afternoon ESE 15 - 25
Wednesday Night SE 15 - 25
Thursday Morning SE 10 - 20
Thursday Afternoon SE 5 - 15
Thursday Night SSE 5 - 15

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
Wednesday Morning NE 10 - 20 NNE 10 - 20 NE 10 - 20 --- - NE 10 - 20
Wednesday Afternoon N 5 - 15 N 5 - 15 NE 0 - 10 --- - SE 5 - 15
Wednesday Night E 0 - 10 NE 0 - 10 SE 5 - 15 --- - SE 5 - 15
Thursday Morning SE 0 - 10 VAR 0 - 10 S 0 - 10 --- - S 5 - 15
Thursday Afternoon SSW 0 - 10 SW 0 - 10 SW 5 - 15 --- - SW 5 - 15
Mt. Baker Direction - Speed
Wednesday Morning NE 10 - 20
Wednesday Afternoon N 5 - 15
Wednesday Night E 0 - 10
Thursday Morning SE 0 - 10
Thursday Afternoon SSW 0 - 10
Thursday Night SW 10 - 20
Washington Pass Direction - Speed
Wednesday Morning NNE 10 - 20
Wednesday Afternoon N 5 - 15
Wednesday Night NE 0 - 10
Thursday Morning VAR 0 - 10
Thursday Afternoon SW 0 - 10
Thursday Night SW 10 - 20
Stevens and Snoqualmie Pass Direction - Speed
Wednesday Morning NE 10 - 20
Wednesday Afternoon NE 0 - 10
Wednesday Night SE 5 - 15
Thursday Morning S 0 - 10
Thursday Afternoon SW 5 - 15
Thursday Night SW 15 - 25
Mt. Rainier Direction - Speed
Wednesday Morning --- -
Wednesday Afternoon --- -
Wednesday Night --- -
Thursday Morning --- -
Thursday Afternoon --- -
Thursday Night --- -
Mt. Hood Direction - Speed
Wednesday Morning NE 10 - 20
Wednesday Afternoon SE 5 - 15
Wednesday Night SE 5 - 15
Thursday Morning S 5 - 15
Thursday Afternoon SW 5 - 15
Thursday Night SW 5 - 15

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 3, 2017

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