Issued: 7:28 AM PDT Sunday, March 23, 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 Sunday & Monday

A rather quiet weather day is in store for the PNW today. Mt. Baker was the only NWAC station to pick a few inches from the weak front that passed to our north Saturday night. An upper level ridge offshore should slowly shift closer today while a deep upper low remains well offshore.  Mostly cloudy skies along the west slopes should give way to mostly sunny skies as seen elsewhere across the region.  Winds will be light with a slight rise in freezing levels and temperatures versus Saturday.  High clouds should increase in the afternoon and tonight.

Warm frontal precipitation may glance the Olympics and north Cascades late Sunday night or Monday.  As the front lifts further north Monday afternoon, with a return to mostly sunny skies at much warmer freezing levels.  Easterly winds at pass and crest levels will counteract this warming to some degree...but since it's late March the cooling effects of easterly flow will be somewhat muted.  Cooler freezing levels are expected over the northeast Cascades Monday.  

The north-south oriented front should push along the Washington coast and Olympics Monday night, possibly spreading light rain and snow inland by late Monday night.  

Weather Forecast

Olympics, Washington Cascades near and west of the crest including Stevens, Snoqualmie, and White Passes and Mt. Hood area
Sunday

Mostly cloudy in the morning becoming mostly sunny with some high clouds in the afternoon.  

Sunday Night - Monday Morning

Increasing mid and high clouds overnight, periods of light rain or snow possible Olympics and north Cascades late tonight and Monday morning.  

Monday Afternoon

Becoming partly to mostly sunny.  Warmer, especially away from the Cascade Passes where easterly flow will initially keep temperatures cooler. 

East slopes of the Washington Cascades
Sunday

Mostly sunny with some high clouds in the afternoon.  

Sunday Night - Monday Morning

Increasing mid and high clouds overnight, periods of light rain or snow possible northeast Cascades late tonight and Monday morning.  

Monday Afternoon

Becoming partly to mostly sunny.  Gradual warming.

Snow/Freezing Level (ft)

Hurricane Ridge Mt. Baker Washington Pass Leavenworth Stevens Pass Snoqualmie Pass Mt. Rainier, Crystal & White Pass Mt. Hood
Sunday Morning Freezing Level 3000' ' ' ' ' 2500' ' 4500'
Sunday Afternoon Freezing Level 5000' ' ' ' ' 5000' ' 7000'
Sunday Night - Monday Morning Freezing Level * 5500' ' ' ' ' 5000' ' 8000'
Monday Afternoon Freezing Level * 8000' ' ' ' ' 7500' ' 8500'
Hurricane Ridge Elevation
Sunday Morning Freezing Level
3000'
Sunday Afternoon Freezing Level
5000'
Sunday Night - Monday Morning Freezing Level
5500'
(Easterly Flow *)
Monday Afternoon Freezing Level
8000'
(Easterly Flow *)
Monday Night Snow Level
5000'
(Easterly Flow *)
Mt. Baker Elevation
Sunday Morning Freezing Level
'
Sunday Afternoon Freezing Level
'
Sunday Night - Monday Morning Freezing Level
'
(Easterly Flow *)
Monday Afternoon Freezing Level
'
(Easterly Flow *)
Monday Night Snow Level
'
(Easterly Flow *)
Washington Pass Elevation
Sunday Morning Freezing Level
'
Sunday Afternoon Freezing Level
'
Sunday Night - Monday Morning Freezing Level
'
(Easterly Flow *)
Monday Afternoon Freezing Level
'
(Easterly Flow *)
Monday Night Snow Level
'
(Easterly Flow *)
Leavenworth Elevation
Sunday Morning Freezing Level
'
Sunday Afternoon Freezing Level
'
Sunday Night - Monday Morning Freezing Level
'
(Easterly Flow *)
Monday Afternoon Freezing Level
'
(Easterly Flow *)
Monday Night Snow Level
'
(Easterly Flow *)
Stevens Pass Elevation
Sunday Morning Freezing Level
'
Sunday Afternoon Freezing Level
'
Sunday Night - Monday Morning Freezing Level
'
(Easterly Flow *)
Monday Afternoon Freezing Level
'
(Easterly Flow *)
Monday Night Snow Level
'
(Easterly Flow *)
Snoqualmie Pass Elevation
Sunday Morning Freezing Level
2500'
Sunday Afternoon Freezing Level
5000'
Sunday Night - Monday Morning Freezing Level
5000'
(Easterly Flow *)
Monday Afternoon Freezing Level
7500'
(Easterly Flow *)
Monday Night Snow Level
4000'
(Easterly Flow *)
Mt. Rainier & Crystal Elevation
Sunday Morning Freezing Level
'
Sunday Afternoon Freezing Level
'
Sunday Night - Monday Morning Freezing Level
'
(Easterly Flow *)
Monday Afternoon Freezing Level
'
(Easterly Flow *)
Monday Night Snow Level
'
(Easterly Flow *)
Mt. Hood Elevation
Sunday Morning Freezing Level
4500'
Sunday Afternoon Freezing Level
7000'
Sunday Night - Monday Morning Freezing Level
8000'
(Easterly Flow *)
Monday Afternoon Freezing Level
8500'
(Easterly Flow *)
Monday 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

Monday Monday
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
Sunday - Sunday Evening WNW 0 - 10 --- - WNW 0 - 10 --- - WNW 0 - 10
Sunday Night - Monday Morning SE 0 - 10 --- - SE 5 - 15 --- - SE 5 - 15
Hurricane Ridge Elevation
Sunday - Sunday Evening WNW 0 - 10
Sunday Night - Monday Morning SE 0 - 10
Monday Afternoon - Monday Night S 15 - 25
Mt. Baker Elevation
Sunday - Sunday Evening --- -
Sunday Night - Monday Morning --- -
Monday Afternoon - Monday Night --- -
Stevens and Snoqualmie Pass Elevation
Sunday - Sunday Evening WNW 0 - 10
Sunday Night - Monday Morning SE 5 - 15
Monday Afternoon - Monday Night SE 15 - 25
Mt. Rainier Elevation
Sunday - Sunday Evening --- -
Sunday Night - Monday Morning --- -
Monday Afternoon - Monday Night --- -
Mt. Hood Elevation
Sunday - Sunday Evening WNW 0 - 10
Sunday Night - Monday Morning SE 5 - 15
Monday Afternoon - Monday Night S 5 - 15
Hurricane Ridge Direction - Speed
Sunday - Sunday Evening WNW 0 - 10
Sunday Night - Monday Morning SE 0 - 10
Monday Afternoon - Monday Night S 15 - 25
Mt. Baker Direction - Speed
Sunday - Sunday Evening --- -
Sunday Night - Monday Morning --- -
Monday Afternoon - Monday Night --- -
Stevens and Snoqualmie Pass Direction - Speed
Sunday - Sunday Evening WNW 0 - 10
Sunday Night - Monday Morning SE 5 - 15
Monday Afternoon - Monday Night SE 15 - 25
Mt. Rainier Direction - Speed
Sunday - Sunday Evening --- -
Sunday Night - Monday Morning --- -
Monday Afternoon - Monday Night --- -
Mt. Hood Direction - Speed
Sunday - Sunday Evening WNW 0 - 10
Sunday Night - Monday Morning SE 5 - 15
Monday Afternoon - Monday Night S 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
Sunday Morning --- - --- - NW 25 - 35 --- - NW 15 - 25
Sunday Afternoon - Monday Morning --- - --- - NW 15 - 25 --- - NW 15 - 25
Mt. Baker Direction - Speed
Sunday Morning --- -
Sunday Afternoon - Monday Morning --- -
Monday Afternoon - Monday Night --- -
Washington Pass Direction - Speed
Sunday Morning --- -
Sunday Afternoon - Monday Morning --- -
Monday Afternoon - Monday Night --- -
Stevens and Snoqualmie Pass Direction - Speed
Sunday Morning NW 25 - 35
Sunday Afternoon - Monday Morning NW 15 - 25
Monday Afternoon - Monday Night SW 20 - 30
Mt. Rainier Direction - Speed
Sunday Morning --- -
Sunday Afternoon - Monday Morning --- -
Monday Afternoon - Monday Night --- -
Mt. Hood Direction - Speed
Sunday Morning NW 15 - 25
Sunday Afternoon - Monday Morning NW 15 - 25
Monday Afternoon - Monday Night SW 20 - 30

Extended Weather Synopsis for Monday night through Monday

The initial frontal wave on Tuesday should be weak and with southerly flow initially favoring the volcanoes and south slopes.  A secondary impulse associated with the upper level low still offshore should rotate through the area Tuesday afternoon or evening, producing a period of moderate rain and snow before transitioning to showers Tuesday night.  A gradual cooling trend should begin Tuesday night as cooler air associated with the upper low moves overhead and stays over the region through the extended forecast period. 

The main trough axis may pass through Wednesday afternoon or night bringing a round of more moderate showers.  Thursday's forecast is uncertain...we may see a decrease in shower activity or a new frontal wave developing and spreading over the area during the day. 

Extended Weather

Olympics, Washington Cascades and Mt. Hood area
Tuesday Morning

Light rain and snow, occasionally moderate at volcanoes and south slopes. 

Tuesday Afternoon - Tuesday Evening

Light to moderate rain and snow. 

Tuesday Night

Mostly cloudy with light to occasionally moderate rain and snow showers along the west slopes.  Cooling trend beginning Tuesday night. 

Wednesday - Thursday

Light, except occasionally moderate rain and snow showers along the west slopes.  Cooler. 

Extended Snow/Freezing Levels

Mt. Baker Snoqualmie Pass Mt. Hood Easterly Flow *
Tuesday Snow Level ' - ' 4000' - 5000' 4500' - 5500'
Mt. Baker Elevation
Tuesday Snow Level
' - '
Tuesday Night - Thursday Snow Level
' - '
Snoqualmie Pass Elevation
Tuesday Snow Level
4000' - 5000'
Tuesday Night - Thursday Snow Level
3000' - 4000'
Mt. Hood Elevation
Tuesday Snow Level
4500' - 5500'
Tuesday Night - Thursday Snow Level
3500' - 4500'

* 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 Mar 22, 2014

The NWAC program is administered by the USDA-Forest Service and operates from the National Weather Service Forecast Office in Seattle. NWAC services are made possible by important collaboration and support from a wide variety of federal, state and private cooperators.