Issued: 1:47 PM PST Tuesday, January 20, 2015
by Dennis D'Amico

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

Weather Synopsis for Tuesday & Friday

A benign weather pattern is in store for the PNW through the short term.  An upper level ridge offshore will lead to dry and mostly sunny weather today and Wednesday. Freezing levels should begin a slow climb today and continue through tomorrow except where easterly flow through the Cascade Passes late Tuesday and tonight should lead to slightly cooler temperatures. 

A weak Pacific frontal system will approach Wednesday night leading to an increase in mid and high level clouds. Very light rain and snow is possible for the Olympics and north Cascades late Wednesday night. 

Weather Forecast

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

Partly cloudy with areas of low clouds and fog becoming mostly sunny in the afternoon.  Gradual warming trend. 
Tuesday Night

Mostly clear. 
Wednesday

Mostly sunny becoming partly to mostly cloudy in the afternoon with increasing high clouds.  Warming trend.  Cooler in the Passes and in the valleys.  
Wednesday Night

Mostly cloudy, very light rain and snow developing north Cascades and Olympics late. 
East slopes of the Washington Cascades
Tuesday

Partly cloudy with areas of low clouds and fog becoming mostly sunny in the afternoon.  
Tuesday Night

Mostly clear. 
Wednesday

Mostly sunny becoming partly to mostly cloudy in the afternoon with increasing high clouds.  Warming trend. 
Wednesday Night

Mostly cloudy, very light rain and snow developing northeast Cascades late. 
Mt. Hood Area
Tuesday

Partly cloudy becoming mostly sunny in the afternoon.  Gradual warming trend. 
Tuesday Night

Mostly clear. 
Wednesday

Mostly sunny becoming partly cloudy in the afternoon with increasing high clouds.  Warming trend.  
Wednesday Night

Becoming mostly cloudy overnight. 

Issued: 1:47 PM PST Tuesday, January 20, 2015

Snow/Freezing Level (ft)

Hurricane Ridge Mt. Baker Washington Pass Leavenworth Stevens Pass Snoqualmie Pass Mt. Rainier, Crystal & White Pass Mt. Hood
Tuesday Afternoon Freezing Level * 5500' 4500' 3000' ' ' 4500' ' 5000'
Tuesday Night - Wednesday Morning Freezing Level * 7000' 6000' 2500' ' ' 5500' ' 5000'
Wednesday Afternoon - Wednesday Evening Freezing Level * 8000' 7000' 4000' ' ' 7000' ' 9000'
Wednesday Night Snow Level * 6000' 3000' 2000' ' ' 3000' ' 5000'
Hurricane Ridge Elevation
Tuesday Afternoon Freezing Level
5500'
(Easterly Flow *)
Tuesday Night - Wednesday Morning Freezing Level
7000'
(Easterly Flow *)
Wednesday Afternoon - Wednesday Evening Freezing Level
8000'
(Easterly Flow *)
Wednesday Night Snow Level
6000'
(Easterly Flow *)
Mt. Baker Elevation
Tuesday Afternoon Freezing Level
4500'
(Easterly Flow *)
Tuesday Night - Wednesday Morning Freezing Level
6000'
(Easterly Flow *)
Wednesday Afternoon - Wednesday Evening Freezing Level
7000'
(Easterly Flow *)
Wednesday Night Snow Level
3000'
(Easterly Flow *)
Washington Pass Elevation
Tuesday Afternoon Freezing Level
3000'
(Easterly Flow *)
Tuesday Night - Wednesday Morning Freezing Level
2500'
(Easterly Flow *)
Wednesday Afternoon - Wednesday Evening Freezing Level
4000'
(Easterly Flow *)
Wednesday Night Snow Level
2000'
(Easterly Flow *)
Leavenworth Elevation
Tuesday Afternoon Freezing Level
'
(Easterly Flow *)
Tuesday Night - Wednesday Morning Freezing Level
'
(Easterly Flow *)
Wednesday Afternoon - Wednesday Evening Freezing Level
'
(Easterly Flow *)
Wednesday Night Snow Level
'
(Easterly Flow *)
Stevens Pass Elevation
Tuesday Afternoon Freezing Level
'
(Easterly Flow *)
Tuesday Night - Wednesday Morning Freezing Level
'
(Easterly Flow *)
Wednesday Afternoon - Wednesday Evening Freezing Level
'
(Easterly Flow *)
Wednesday Night Snow Level
'
(Easterly Flow *)
Snoqualmie Pass Elevation
Tuesday Afternoon Freezing Level
4500'
(Easterly Flow *)
Tuesday Night - Wednesday Morning Freezing Level
5500'
(Easterly Flow *)
Wednesday Afternoon - Wednesday Evening Freezing Level
7000'
(Easterly Flow *)
Wednesday Night Snow Level
3000'
(Easterly Flow *)
Mt. Rainier & Crystal Elevation
Tuesday Afternoon Freezing Level
'
(Easterly Flow *)
Tuesday Night - Wednesday Morning Freezing Level
'
(Easterly Flow *)
Wednesday Afternoon - Wednesday Evening Freezing Level
'
(Easterly Flow *)
Wednesday Night Snow Level
'
(Easterly Flow *)
Mt. Hood Elevation
Tuesday Afternoon Freezing Level
5000'
(Easterly Flow *)
Tuesday Night - Wednesday Morning Freezing Level
5000'
(Easterly Flow *)
Wednesday Afternoon - Wednesday Evening Freezing Level
9000'
(Easterly Flow *)
Wednesday Night Snow Level
5000'
(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
Timberline LT 0.10 LT 0.10

LT = less than; WE or Water equivalent is the liquid water equivalent of melted snow in hundredths of inches. As a rough approximation 1 inch of snow = about .10 inches WE, or 10 inches of snow = about 1 inch WE.

Issued: 1:47 PM PST Tuesday, January 20, 2015

Free Winds at 5000' (mph)

Hurricane Ridge Mt. Baker Stevens to Snoqualmie Pass Mt. Rainier Mt. Hood
Tuesday NE 0 - 10 NE 0 - 10 E 0 - 10 --- - E 5 - 15
Tuesday Night S 0 - 10 S 0 - 10 E 0 - 10 --- - SE 5 - 15
Wednesday SW 5 - 15 SW 5 - 15 SE 0 - 10 --- - SE 0 - 10
Wednesday Night SW 10 - 20 SE 5 - 15 SW 0 - 10 --- - SW 5 - 15
Hurricane Ridge Elevation
Tuesday NE 0 - 10
Tuesday Night S 0 - 10
Wednesday SW 5 - 15
Wednesday Night SW 10 - 20
Mt. Baker Elevation
Tuesday NE 0 - 10
Tuesday Night S 0 - 10
Wednesday SW 5 - 15
Wednesday Night SE 5 - 15
Stevens and Snoqualmie Pass Elevation
Tuesday E 0 - 10
Tuesday Night E 0 - 10
Wednesday SE 0 - 10
Wednesday Night SW 0 - 10
Mt. Rainier Elevation
Tuesday --- -
Tuesday Night --- -
Wednesday --- -
Wednesday Night --- -
Mt. Hood Elevation
Tuesday E 5 - 15
Tuesday Night SE 5 - 15
Wednesday SE 0 - 10
Wednesday Night SW 5 - 15
Hurricane Ridge Direction - Speed
Tuesday NE 0 - 10
Tuesday Night S 0 - 10
Wednesday SW 5 - 15
Wednesday Night SW 10 - 20
Mt. Baker Direction - Speed
Tuesday NE 0 - 10
Tuesday Night S 0 - 10
Wednesday SW 5 - 15
Wednesday Night SE 5 - 15
Stevens and Snoqualmie Pass Direction - Speed
Tuesday E 0 - 10
Tuesday Night E 0 - 10
Wednesday SE 0 - 10
Wednesday Night SW 0 - 10
Mt. Rainier Direction - Speed
Tuesday --- -
Tuesday Night --- -
Wednesday --- -
Wednesday Night --- -
Mt. Hood Direction - Speed
Tuesday E 5 - 15
Tuesday Night SE 5 - 15
Wednesday SE 0 - 10
Wednesday 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.

Free Winds at 9000' (mph)

Mt. Baker Washington Pass Stevens to Snoqualmie Pass Mt. Rainier Mt. Hood
Tuesday Afternoon NW 5 - 15 NW 5 - 15 N 0 - 10 --- - NE 0 - 10
Tuesday Night W 10 - 20 W 10 - 20 W 5 - 15 --- - W 5 - 15
Wednesday SW 10 - 20 W 10 - 20 SW 5 - 15 --- - SW 5 - 15
Wednesday Night W 15 - 25 W 15 - 25 W 15 - 25 --- - W 10 - 20
Mt. Baker Direction - Speed
Tuesday Afternoon NW 5 - 15
Tuesday Night W 10 - 20
Wednesday SW 10 - 20
Wednesday Night W 15 - 25
Washington Pass Direction - Speed
Tuesday Afternoon NW 5 - 15
Tuesday Night W 10 - 20
Wednesday W 10 - 20
Wednesday Night W 15 - 25
Stevens and Snoqualmie Pass Direction - Speed
Tuesday Afternoon N 0 - 10
Tuesday Night W 5 - 15
Wednesday SW 5 - 15
Wednesday Night W 15 - 25
Mt. Rainier Direction - Speed
Tuesday Afternoon --- -
Tuesday Night --- -
Wednesday --- -
Wednesday Night --- -
Mt. Hood Direction - Speed
Tuesday Afternoon NE 0 - 10
Tuesday Night W 5 - 15
Wednesday SW 5 - 15
Wednesday Night W 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.

Issued: 1:47 PM PST Tuesday, January 20, 2015

Extended Weather Synopsis for Friday night through Friday

The upper level ridge off the California Coast will strengthen over the weekend and eventually bring much warmer air into the region while deflecting heavier precipitation well to our north. 

Before the happens, another weak system may move through the area Thursday and again on Friday at relatively mild snow levels. Forecast guidance now looks a bit wetter with these system. Easterly flow may cause a mix of precipitation types in the passes on Thursday.  

A stronger slug of moisture should affect the Olympics and north Cascades on Saturday before shifting north into British Columbia as the upper ridge amplifies offshore. Mt. Hood may see very little precipitation from this event on Saturday. 

Extended Weather

Olympics, Washington Cascades and Mt. Hood area
Thursday - Friday

Cloudy with periods of light rain and snow, occasionally moderate west slopes Olympics and Cascades. Slow warming trend. 

Friday Night - Saturday

Cloudy with light to moderate rain and snow, heaviest north Cascades and Olympics. Mild.  

Extended Snow/Freezing Levels

Mt. Baker Snoqualmie Pass Mt. Hood Easterly Flow *
Thursday Morning Snow Level 3500' - 4500' 3000' - 4000' 4500' - 5500' *
Friday Afternoon - Saturday Snow Level 7000' - 8000' 8000' - 9000' 9000' - 10000'
Thursday Afternoon - Friday Morning Snow Level 5000' - 6000' 6000' - 7000' 6500' - 7500' *
Mt. Baker Elevation
Thursday Morning Snow Level
3500' - 4500'
(Easterly Flow *)
Friday Afternoon - Saturday Snow Level
7000' - 8000'
Thursday Afternoon - Friday Morning Snow Level
5000' - 6000'
(Easterly Flow *)
Snoqualmie Pass Elevation
Thursday Morning Snow Level
3000' - 4000'
(Easterly Flow *)
Friday Afternoon - Saturday Snow Level
8000' - 9000'
Thursday Afternoon - Friday Morning Snow Level
6000' - 7000'
(Easterly Flow *)
Mt. Hood Elevation
Thursday Morning Snow Level
4500' - 5500'
(Easterly Flow *)
Friday Afternoon - Saturday Snow Level
9000' - 10000'
Thursday Afternoon - Friday Morning Snow Level
6500' - 7500'
(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.

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

Previous forecast from Jan 20, 2015

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