Issued: 7:00 AM PST Tuesday, December 12, 2017
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 Tuesday & Friday

Here comes another day of dry and mild conditions for the mountains of the Pacific Northwest. Change is in sight later this week...but not over the next two days.  High freezing levels with temperatures inversions and low clouds in the Cascade Passes and along lower elevations of the east slopes Cascades will continue through the short term.

The caveat for today will be periods of high clouds affecting much of the area as a weak frontal system well to our north temporarily flattens the upper level ridge over the area. Offshore gradients will also weaken slightly today. The ridge axis will retrograde offshore Tuesday night and amplify offshore on Wednesday, helping temperatures increase once again as well as increasing offshore easterly gradients. 

Weather Forecast

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

Periods of high clouds. Mild except locally cooler with areas of low clouds Cascade Passes. 

Tuesday Night

Periods of high clouds. Mild except locally cooler with areas of low clouds Cascade Passes. 

Wednesday

Mostly sunny. Mild except locally cooler with areas of low clouds Cascade Passes. 

East slopes of the Washington Cascades
Tuesday

Periods of high clouds. Mild higher elevations and cooler lower slopes with low clouds. 

Tuesday Night

Periods of high clouds. Mild higher elevations and cooler lower slopes with low clouds. 

Wednesday

Mostly sunny. Mild except locally cooler with areas of low clouds lower slopes. 

Olympics
Tuesday

Periods of high clouds. Mild. 

Tuesday Night

Periods of high clouds. Mild. 

Wednesday

Mostly sunny. Mild. 

Mt. Hood Area
Tuesday

Mostly sunny with occasional high clouds. Mild. 

Tuesday Night

Mostly clear. Mild. 

Wednesday

Mostly sunny. Mild except locally cooler lower slopes.

Snow/Freezing Level (ft)

Hurricane Ridge Mt. Baker Washington Pass Leavenworth Stevens Pass Snoqualmie Pass Mt. Rainier, Crystal & White Pass Mt. Hood
Tuesday Snow Level * 8500' 8000' 7500' ' ' 9500' ' 11500'
Tuesday Night Snow Level * 10000' 9000' 8000' ' ' 10000' ' 12000'
Wednesday Snow Level * 12000' 11000' 11000' ' ' 12000' ' 12500'
Hurricane Ridge Elevation
Tuesday Snow Level
8500'
(Easterly Flow *)
Tuesday Night Snow Level
10000'
(Easterly Flow *)
Wednesday Snow Level
12000'
(Easterly Flow *)
Wednesday Night Snow Level
12000'
(Easterly Flow *)
Mt. Baker Elevation
Tuesday Snow Level
8000'
(Easterly Flow *)
Tuesday Night Snow Level
9000'
(Easterly Flow *)
Wednesday Snow Level
11000'
(Easterly Flow *)
Wednesday Night Snow Level
11000'
(Easterly Flow *)
Washington Pass Elevation
Tuesday Snow Level
7500'
(Easterly Flow *)
Tuesday Night Snow Level
8000'
(Easterly Flow *)
Wednesday Snow Level
11000'
(Easterly Flow *)
Wednesday Night Snow Level
11000'
(Easterly Flow *)
Leavenworth Elevation
Tuesday Snow Level
'
(Easterly Flow *)
Tuesday Night Snow Level
'
(Easterly Flow *)
Wednesday Snow Level
'
(Easterly Flow *)
Wednesday Night Snow Level
'
(Easterly Flow *)
Stevens Pass Elevation
Tuesday Snow Level
'
(Easterly Flow *)
Tuesday Night Snow Level
'
(Easterly Flow *)
Wednesday Snow Level
'
(Easterly Flow *)
Wednesday Night Snow Level
'
(Easterly Flow *)
Snoqualmie Pass Elevation
Tuesday Snow Level
9500'
(Easterly Flow *)
Tuesday Night Snow Level
10000'
(Easterly Flow *)
Wednesday Snow Level
12000'
(Easterly Flow *)
Wednesday Night Snow Level
12000'
(Easterly Flow *)
Mt. Rainier & Crystal Elevation
Tuesday Snow Level
'
(Easterly Flow *)
Tuesday Night Snow Level
'
(Easterly Flow *)
Wednesday Snow Level
'
(Easterly Flow *)
Wednesday Night Snow Level
'
(Easterly Flow *)
Mt. Hood Elevation
Tuesday Snow Level
11500'
(Easterly Flow *)
Tuesday Night Snow Level
12000'
(Easterly Flow *)
Wednesday Snow Level
12500'
(Easterly Flow *)
Wednesday Night Snow Level
12500'
(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
Tuesday Morning SW 5 - 15 SW 5 - 15 SW 5 - 15 --- - SW 5 - 15
Tuesday Afternoon SW 0 - 10 SW 0 - 10 W 0 - 10 --- - W 5 - 15
Tuesday Night N 0 - 10 N 0 - 10 NW 0 - 10 --- - NW 0 - 10
Wednesday Morning NE 5 - 15 NE 0 - 10 E 0 - 10 --- - E 5 - 15
Wednesday Afternoon ENE 0 - 10 NE 0 - 10 E 5 - 15 --- - E 10 - 20
Hurricane Ridge Elevation
Tuesday Morning SW 5 - 15
Tuesday Afternoon SW 0 - 10
Tuesday Night N 0 - 10
Wednesday Morning NE 5 - 15
Wednesday Afternoon ENE 0 - 10
Wednesday Night S 0 - 10
Mt. Baker Elevation
Tuesday Morning SW 5 - 15
Tuesday Afternoon SW 0 - 10
Tuesday Night N 0 - 10
Wednesday Morning NE 0 - 10
Wednesday Afternoon NE 0 - 10
Wednesday Night SE 0 - 10
Stevens and Snoqualmie Pass Elevation
Tuesday Morning SW 5 - 15
Tuesday Afternoon W 0 - 10
Tuesday Night NW 0 - 10
Wednesday Morning E 0 - 10
Wednesday Afternoon E 5 - 15
Wednesday Night ESE 5 - 15
Mt. Rainier Elevation
Tuesday Morning --- -
Tuesday Afternoon --- -
Tuesday Night --- -
Wednesday Morning --- -
Wednesday Afternoon --- -
Wednesday Night --- -
Mt. Hood Elevation
Tuesday Morning SW 5 - 15
Tuesday Afternoon W 5 - 15
Tuesday Night NW 0 - 10
Wednesday Morning E 5 - 15
Wednesday Afternoon E 10 - 20
Wednesday Night ESE 10 - 20
Hurricane Ridge Direction - Speed
Tuesday Morning SW 5 - 15
Tuesday Afternoon SW 0 - 10
Tuesday Night N 0 - 10
Wednesday Morning NE 5 - 15
Wednesday Afternoon ENE 0 - 10
Wednesday Night S 0 - 10
Mt. Baker Direction - Speed
Tuesday Morning SW 5 - 15
Tuesday Afternoon SW 0 - 10
Tuesday Night N 0 - 10
Wednesday Morning NE 0 - 10
Wednesday Afternoon NE 0 - 10
Wednesday Night SE 0 - 10
Stevens and Snoqualmie Pass Direction - Speed
Tuesday Morning SW 5 - 15
Tuesday Afternoon W 0 - 10
Tuesday Night NW 0 - 10
Wednesday Morning E 0 - 10
Wednesday Afternoon E 5 - 15
Wednesday Night ESE 5 - 15
Mt. Rainier Direction - Speed
Tuesday Morning --- -
Tuesday Afternoon --- -
Tuesday Night --- -
Wednesday Morning --- -
Wednesday Afternoon --- -
Wednesday Night --- -
Mt. Hood Direction - Speed
Tuesday Morning SW 5 - 15
Tuesday Afternoon W 5 - 15
Tuesday Night NW 0 - 10
Wednesday Morning E 5 - 15
Wednesday Afternoon E 10 - 20
Wednesday Night ESE 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
Tuesday Morning SW 25 - 35 SW 25 - 35 SW 30 - 40 --- - SW 20 - 30
Tuesday Afternoon W 10 - 20 W 15 - 25 W 20 - 30 --- - SW 20 - 30
Tuesday Night NW 10 - 20 WNW 10 - 20 WNW 20 - 30 --- - NW 15 - 25
Wednesday Morning N 10 - 20 N 10 - 20 N 15 - 25 --- - NW 10 - 20
Wednesday Afternoon N 0 - 10 NNW 5 - 15 NW 0 - 10 --- - N 0 - 10
Mt. Baker Direction - Speed
Tuesday Morning SW 25 - 35
Tuesday Afternoon W 10 - 20
Tuesday Night NW 10 - 20
Wednesday Morning N 10 - 20
Wednesday Afternoon N 0 - 10
Wednesday Night W 5 - 15
Washington Pass Direction - Speed
Tuesday Morning SW 25 - 35
Tuesday Afternoon W 15 - 25
Tuesday Night WNW 10 - 20
Wednesday Morning N 10 - 20
Wednesday Afternoon NNW 5 - 15
Wednesday Night WSW 5 - 15
Stevens and Snoqualmie Pass Direction - Speed
Tuesday Morning SW 30 - 40
Tuesday Afternoon W 20 - 30
Tuesday Night WNW 20 - 30
Wednesday Morning N 15 - 25
Wednesday Afternoon NW 0 - 10
Wednesday Night W 5 - 15
Mt. Rainier Direction - Speed
Tuesday Morning --- -
Tuesday Afternoon --- -
Tuesday Night --- -
Wednesday Morning --- -
Wednesday Afternoon --- -
Wednesday Night --- -
Mt. Hood Direction - Speed
Tuesday Morning SW 20 - 30
Tuesday Afternoon SW 20 - 30
Tuesday Night NW 15 - 25
Wednesday Morning NW 10 - 20
Wednesday Afternoon N 0 - 10
Wednesday Night NW 0 - 10

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 11, 2017

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