Issued: 7:28 AM PST Tuesday, January 10, 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 & Thursday

A weak surface low will traverse across southern Washington this morning and bring a period of generally light snow to the south and central Washington Cascades with continuing moderate accumulations down at Mt. Hood. Light upslope snow showers are likely along the north slopes of the Olympics today with breezy NE winds. The surface low is part of the E-W elongated trough stretched out over Washington state with the upper low centered offshore.  

A stronger low pressure system developing in the westerly jet aimed at northern California will approach the south Oregon coast this afternoon. Besides spreading renewed precipitation into the Mt. Hood region this afternoon, the pressure falls associated with this low pressure system will turn the winds E-NE throughout the Cascades and Olympics.

Forecast models indicate precipitation largely confined to the far south Washington Cascades and Mt. Hood tonight, but it's reasonable to assume their will be some light upslope snow showers along the east slopes from Mission Ridge and south overnight. The surface low will dissipate as it moves inland Wednesday morning but the weak upper level low circulation will remain parked off the WA/OR coast on Wednesday. Cold easterly flow should ease Wednesday afternoon but clouds should be more plentiful for both sides of the central and south Washington Cascades with mostly clear conditions expected close to the Canadian border through much of the short term period. 

Weather Forecast

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

Cloudy with periods of light snow mainly south Washington Cascades. Partly to mostly clear north Cascades. Light to moderate E-NE winds developing this afternoon through Tuesday night. Turning colder. 

Wednesday Afternoon

Mostly sunny north Cascades. Mostly cloudy with scattered snow showers central and south Washington Cascades. 

East slopes of the Washington Cascades
Tuesday - Wednesday Morning

Cloudy with periods of light snow mainly southeast Washington Cascades. Mostly clear northeast Cascades. Light to moderate E-NE winds developing this afternoon through Tuesday night. Turning colder. 

Wednesday Afternoon

Mostly sunny northeast Cascades. Partly to mostly cloudy with isolated snow showers central and southeast Washington Cascades. 

Mt. Hood Area
Tuesday - Wednesday Morning

Light to occasionally moderate snow. Moderate E winds developing this afternoon through Tuesday night. Turning colder. 

Wednesday Afternoon

Mostly cloudy with scattered snow showers. 

Olympics
Tuesday - Tuesday Night

Partly to mostly cloudy with light snow showers north slopes of the Olympics. Light to moderate NE winds developing this afternoon through Tuesday night. Turning colder. 

Wednesday

Partly to mostly sunny. 

Snow/Freezing Level (ft)

Hurricane Ridge Mt. Baker Washington Pass Leavenworth Stevens Pass Snoqualmie Pass Mt. Rainier, Crystal & White Pass Mt. Hood
Tuesday Morning Snow Level * 1000' 0' 0' ' ' 500' ' 2500'
Tuesday Afternoon Snow Level * 0' 0' 0' ' ' 0' ' 500'
Hurricane Ridge Elevation
Tuesday Morning Snow Level
1000'
(Easterly Flow *)
Tuesday Afternoon Snow Level
0'
(Easterly Flow *)
Tuesday Night - Wednesday Night Snow Level
0'
(Easterly Flow *)
Mt. Baker Elevation
Tuesday Morning Snow Level
0'
(Easterly Flow *)
Tuesday Afternoon Snow Level
0'
(Easterly Flow *)
Tuesday Night - Wednesday Night Snow Level
0'
(Easterly Flow *)
Washington Pass Elevation
Tuesday Morning Snow Level
0'
(Easterly Flow *)
Tuesday Afternoon Snow Level
0'
(Easterly Flow *)
Tuesday Night - Wednesday Night Snow Level
0'
(Easterly Flow *)
Leavenworth Elevation
Tuesday Morning Snow Level
'
(Easterly Flow *)
Tuesday Afternoon Snow Level
'
(Easterly Flow *)
Tuesday Night - Wednesday Night Snow Level
'
(Easterly Flow *)
Stevens Pass Elevation
Tuesday Morning Snow Level
'
(Easterly Flow *)
Tuesday Afternoon Snow Level
'
(Easterly Flow *)
Tuesday Night - Wednesday Night Snow Level
'
(Easterly Flow *)
Snoqualmie Pass Elevation
Tuesday Morning Snow Level
500'
(Easterly Flow *)
Tuesday Afternoon Snow Level
0'
(Easterly Flow *)
Tuesday Night - Wednesday Night Snow Level
0'
(Easterly Flow *)
Mt. Rainier & Crystal Elevation
Tuesday Morning Snow Level
'
(Easterly Flow *)
Tuesday Afternoon Snow Level
'
(Easterly Flow *)
Tuesday Night - Wednesday Night Snow Level
'
(Easterly Flow *)
Mt. Hood Elevation
Tuesday Morning Snow Level
2500'
(Easterly Flow *)
Tuesday Afternoon Snow Level
500'
(Easterly Flow *)
Tuesday Night - Wednesday Night Snow Level
0'
(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

Thursday Thursday
Hurricane Ridge LT 0.25 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 0.25 LT 0.10
Mission Ridge LT 0.25 LT 0.10
Crystal Mt 0.25 - 0.50 LT 0.10
Paradise 0.25 - 0.50 LT 0.10
White Pass LT 0.25 LT 0.10
Mt Hood Meadows 0.75 - 1.00 LT 0.25
0.75 - 1.00 LT 0.25

Free Winds at 5000' (mph)

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

Free Winds at 9000' (mph)

Mt. Baker Washington Pass Stevens to Snoqualmie Pass Mt. Rainier Mt. Hood
Tuesday Morning WSW 5 - 15 W 5 - 15 SW 5 - 15 --- - WSW 25 - 35
Tuesday Afternoon NE 15 - 25 N 10 - 20 E 15 - 25 --- - S 20 - 30
Tuesday Night ENE 10 - 20 NE 10 - 20 E 15 - 25 --- - SW 25 - 35
Wednesday Morning ENE 5 - 15 NE 5 - 15 SE 10 - 20 --- - SW 10 - 20
Mt. Baker Direction - Speed
Tuesday Morning WSW 5 - 15
Tuesday Afternoon NE 15 - 25
Tuesday Night ENE 10 - 20
Wednesday Morning ENE 5 - 15
Wednesday Afternoon - Wednesday Night NE 5 - 15
Washington Pass Direction - Speed
Tuesday Morning W 5 - 15
Tuesday Afternoon N 10 - 20
Tuesday Night NE 10 - 20
Wednesday Morning NE 5 - 15
Wednesday Afternoon - Wednesday Night N 0 - 10
Stevens and Snoqualmie Pass Direction - Speed
Tuesday Morning SW 5 - 15
Tuesday Afternoon E 15 - 25
Tuesday Night E 15 - 25
Wednesday Morning SE 10 - 20
Wednesday Afternoon - Wednesday Night VAR 0 - 10
Mt. Rainier Direction - Speed
Tuesday Morning --- -
Tuesday Afternoon --- -
Tuesday Night --- -
Wednesday Morning --- -
Wednesday Afternoon - Wednesday Night --- -
Mt. Hood Direction - Speed
Tuesday Morning WSW 25 - 35
Tuesday Afternoon S 20 - 30
Tuesday Night SW 25 - 35
Wednesday Morning SW 10 - 20
Wednesday Afternoon - Wednesday Night WSW 20 - 30

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 Jan 9, 2017

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