Issued: 2:28 PM PDT Thursday, April 10, 2014
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 Thursday & Friday

The northerly jet will continue to direct weather systems into central British Columbia today. Only high clouds should affect the northern half of the Cascades and Olympics...with clearer skies further south into Mt. Hood.  An upper level trough of low pressure should dig over southern B.C and Washington state on Friday...leading to a chance of showers mainly for the north Cascades. Snow levels should dip slightly on Friday and crest level winds should become breezy during the day as well.  An increase in onshore flow and low level moisture should make for a mostly cloudy day over the west slopes of the north Cascades with partly to mostly sunny conditions further south. The chance for showers will diminish Friday night as an upper level ridge amplifies offshore and the upper level trough passes into Montana.  

Weather Forecast

North Washington Cascades
Thursday - Thursday Night

Mostly cloudy. 

Olympics and South and Central Washington Cascades
Thursday - Thursday Night

Partly to mostly clear, cloudier central Washington Cascades. 

Friday - Friday Evening

Partly cloudy, except mostly cloudy west slopes of the central Washington Cascades.  Isolated rain and snow showers. 

Mt. Hood Area

Snow/Freezing Level (ft)

Hurricane Ridge Mt. Baker Washington Pass Leavenworth Stevens Pass Snoqualmie Pass Mt. Rainier, Crystal & White Pass Mt. Hood
Thursday Afternoon - Thursday Night Freezing Level 6000' ' ' ' ' 7000' ' 9500'
Friday Morning Snow Level 5000' ' ' ' ' 4500' ' 6500'
Friday Afternoon - Friday Evening Snow Level 5000' ' ' ' ' 5000' ' 8000'
Hurricane Ridge Elevation
Thursday Afternoon - Thursday Night Freezing Level
6000'
Friday Morning Snow Level
5000'
Friday Afternoon - Friday Evening Snow Level
5000'
Friday Night Freezing Level
4000'
Mt. Baker Elevation
Thursday Afternoon - Thursday Night Freezing Level
'
Friday Morning Snow Level
'
Friday Afternoon - Friday Evening Snow Level
'
Friday Night Freezing Level
'
Washington Pass Elevation
Thursday Afternoon - Thursday Night Freezing Level
'
Friday Morning Snow Level
'
Friday Afternoon - Friday Evening Snow Level
'
Friday Night Freezing Level
'
Leavenworth Elevation
Thursday Afternoon - Thursday Night Freezing Level
'
Friday Morning Snow Level
'
Friday Afternoon - Friday Evening Snow Level
'
Friday Night Freezing Level
'
Stevens Pass Elevation
Thursday Afternoon - Thursday Night Freezing Level
'
Friday Morning Snow Level
'
Friday Afternoon - Friday Evening Snow Level
'
Friday Night Freezing Level
'
Snoqualmie Pass Elevation
Thursday Afternoon - Thursday Night Freezing Level
7000'
Friday Morning Snow Level
4500'
Friday Afternoon - Friday Evening Snow Level
5000'
Friday Night Freezing Level
4000'
Mt. Rainier & Crystal Elevation
Thursday Afternoon - Thursday Night Freezing Level
'
Friday Morning Snow Level
'
Friday Afternoon - Friday Evening Snow Level
'
Friday Night Freezing Level
'
Mt. Hood Elevation
Thursday Afternoon - Thursday Night Freezing Level
9500'
Friday Morning Snow Level
6500'
Friday Afternoon - Friday Evening Snow Level
8000'
Friday Night Freezing Level
8000'

* 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 0.25
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
Thursday Afternoon - Thursday Night NW 5 - 15 --- - NW 5 - 15 --- - NW 5 - 15
Friday NW 10 - 20 --- - NW 10 - 20 --- - NW 10 - 20
Hurricane Ridge Elevation
Thursday Afternoon - Thursday Night NW 5 - 15
Friday NW 10 - 20
Friday Night N 0 - 10
Mt. Baker Elevation
Thursday Afternoon - Thursday Night --- -
Friday --- -
Friday Night --- -
Stevens and Snoqualmie Pass Elevation
Thursday Afternoon - Thursday Night NW 5 - 15
Friday NW 10 - 20
Friday Night NW 0 - 10
Mt. Rainier Elevation
Thursday Afternoon - Thursday Night --- -
Friday --- -
Friday Night --- -
Mt. Hood Elevation
Thursday Afternoon - Thursday Night NW 5 - 15
Friday NW 10 - 20
Friday Night NW 5 - 15
Hurricane Ridge Direction - Speed
Thursday Afternoon - Thursday Night NW 5 - 15
Friday NW 10 - 20
Friday Night N 0 - 10
Mt. Baker Direction - Speed
Thursday Afternoon - Thursday Night --- -
Friday --- -
Friday Night --- -
Stevens and Snoqualmie Pass Direction - Speed
Thursday Afternoon - Thursday Night NW 5 - 15
Friday NW 10 - 20
Friday Night NW 0 - 10
Mt. Rainier Direction - Speed
Thursday Afternoon - Thursday Night --- -
Friday --- -
Friday Night --- -
Mt. Hood Direction - Speed
Thursday Afternoon - Thursday Night NW 5 - 15
Friday NW 10 - 20
Friday Night NW 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
Thursday Afternoon - Thursday Night --- - --- - NW 15 - 25 --- - WNW 10 - 20
Friday Morning --- - --- - NW 30 - 40 --- - NW 15 - 25
Friday Afternoon - Friday Evening --- - --- - NW 30 - 45 --- - NW 25 - 35
Mt. Baker Direction - Speed
Thursday Afternoon - Thursday Night --- -
Friday Morning --- -
Friday Afternoon - Friday Evening --- -
Friday Night --- -
Washington Pass Direction - Speed
Thursday Afternoon - Thursday Night --- -
Friday Morning --- -
Friday Afternoon - Friday Evening --- -
Friday Night --- -
Stevens and Snoqualmie Pass Direction - Speed
Thursday Afternoon - Thursday Night NW 15 - 25
Friday Morning NW 30 - 40
Friday Afternoon - Friday Evening NW 30 - 45
Friday Night NW 15 - 25
Mt. Rainier Direction - Speed
Thursday Afternoon - Thursday Night --- -
Friday Morning --- -
Friday Afternoon - Friday Evening --- -
Friday Night --- -
Mt. Hood Direction - Speed
Thursday Afternoon - Thursday Night WNW 10 - 20
Friday Morning NW 15 - 25
Friday Afternoon - Friday Evening NW 25 - 35
Friday Night NW 20 - 30

Extended Weather Synopsis for Friday night through Friday

The upper level ridge located at 130W on Saturday afternoon should slowly migrate eastward over the weekend.  Dry and increasingly warmer weather is expected over the weekend.  On Saturday...freezing levels will moderate as low clouds along the west slopes give way to mostly sunny skies in the afternoon with drier northerly flow aloft.  Warmer air should make it's way over the region on Sunday with freezing levels nearing 10000 feet in many areas. However, breezy easterlies winds up to crest level should develop in response to increasing offshore flow Saturday night and Sunday.  An approaching shortwave trough may swing into Vancouver Island early Monday and knock freezing levels down during the day. 

Extended Weather

Olympics, Washington Cascades and Mt. Hood Area
Saturday - Sunday Morning

Mostly clear, except mostly cloudy along the west slopes Saturday morning.   

Sunday Afternoon - Sunday Night

Mostly clear and warm. 

Monday

Partly cloudy north part, mostly sunny south part.  Cooling trend west slopes of the Cascades. 

Extended Snow/Freezing Levels

Mt. Baker Snoqualmie Pass Mt. Hood Easterly Flow *
Saturday - Sunday Morning Freezing Level ' - ' 6000' - 7000' 7000' - 8500'
Sunday Afternoon - Sunday Night Freezing Level ' - ' 8500' - 9500' 9500' - 10500'
Mt. Baker Elevation
Saturday - Sunday Morning Freezing Level
' - '
Sunday Afternoon - Sunday Night Freezing Level
' - '
Monday Freezing Level
' - '
Snoqualmie Pass Elevation
Saturday - Sunday Morning Freezing Level
6000' - 7000'
Sunday Afternoon - Sunday Night Freezing Level
8500' - 9500'
Monday Freezing Level
6000' - 8000'
Mt. Hood Elevation
Saturday - Sunday Morning Freezing Level
7000' - 8500'
Sunday Afternoon - Sunday Night Freezing Level
9500' - 10500'
Monday Freezing Level
7000' - 9000'

* 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 Apr 10, 2014

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