Issued: 2:33 PM PDT Tuesday, March 14, 2017
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 & Sunday

Moist W-SW flow will continue to deliver mainly rain to the Cascades and Olympics today and tonight with a relative lull this afternoon (but still not dry). Low level easterly flow through the Cascade Passes early this morning locally suppressed snow levels to around 6000 feet. Snow levels have since risen to 7000 feet or higher for all areas this afternoon. SW winds at crest level will stay elevated throughout the short term.  

Another wave currently offshore and moving along the frontal boundary will shift steadier and heavier precipitation back into the area overnight. One last slug of moisture associated with this frontal boundary will develop off the Oregon coast early Wednesday morning and finally shift the entire axis of precipitation east of the Cascades Wednesday evening.

A slow cooling trend should begin on Wednesday with accumulating snows likely in the alpine throughout the day. Snow levels will cool significantly Wednesday night as we transition to showers.   

Weather Forecast

Olympics
Tuesday Afternoon

Cloudy with periods of light rain. Mild. 

Tuesday Night

Light to moderate rain and snow. Mild. 

Wednesday

Light rain and snow. Slow cooling trend. 

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

Cloudy with periods of light rain, occasionally moderate southern Cascade volcanoes. Mild. 

Tuesday Night

Moderate rain and snow. Mild. 

Wednesday

Light to moderate rain and snow, heaviest south Washington Cascades. Slow cooling trend. 

East slopes of the Washington Cascades
Tuesday Afternoon

Cloudy with periods of light rain. Mild. 

Tuesday Night

Light to occasionally moderate rain and snow. Mild. 

Wednesday

Light to occasionally moderate rain and snow, heaviest southeast Washington Cascades. 

Mt. Hood Area
Tuesday

Cloudy with periods of light rain and snow. Mild. 

Tuesday Night

Light to occasionally moderate rain and snow. Mild. 

Wednesday

Light to moderate rain and snow. Slow cooling trend. 

Snow/Freezing Level (ft)

Hurricane Ridge Mt. Baker Washington Pass Leavenworth Stevens Pass Snoqualmie Pass Mt. Rainier, Crystal & White Pass Mt. Hood
Tuesday Afternoon - Tuesday Night Snow Level 7000' 7000' 7000' ' ' 7500' ' 8000'
Tuesday Night - Wednesday Morning Snow Level 6000' 6000' 6500' ' ' 6500' ' 7500'
Wednesday Afternoon Snow Level 4500' 4500' 5500' ' ' 5500' ' 6000'
Hurricane Ridge Elevation
Tuesday Afternoon - Tuesday Night Snow Level
7000'
Tuesday Night - Wednesday Morning Snow Level
6000'
Wednesday Afternoon Snow Level
4500'
Wednesday Night Snow Level
3000'
Mt. Baker Elevation
Tuesday Afternoon - Tuesday Night Snow Level
7000'
Tuesday Night - Wednesday Morning Snow Level
6000'
Wednesday Afternoon Snow Level
4500'
Wednesday Night Snow Level
3000'
Washington Pass Elevation
Tuesday Afternoon - Tuesday Night Snow Level
7000'
Tuesday Night - Wednesday Morning Snow Level
6500'
Wednesday Afternoon Snow Level
5500'
Wednesday Night Snow Level
3000'
Leavenworth Elevation
Tuesday Afternoon - Tuesday Night Snow Level
'
Tuesday Night - Wednesday Morning Snow Level
'
Wednesday Afternoon Snow Level
'
Wednesday Night Snow Level
'
Stevens Pass Elevation
Tuesday Afternoon - Tuesday Night Snow Level
'
Tuesday Night - Wednesday Morning Snow Level
'
Wednesday Afternoon Snow Level
'
Wednesday Night Snow Level
'
Snoqualmie Pass Elevation
Tuesday Afternoon - Tuesday Night Snow Level
7500'
Tuesday Night - Wednesday Morning Snow Level
6500'
Wednesday Afternoon Snow Level
5500'
Wednesday Night Snow Level
3000'
Mt. Rainier & Crystal Elevation
Tuesday Afternoon - Tuesday Night Snow Level
'
Tuesday Night - Wednesday Morning Snow Level
'
Wednesday Afternoon Snow Level
'
Wednesday Night Snow Level
'
Mt. Hood Elevation
Tuesday Afternoon - Tuesday Night Snow Level
8000'
Tuesday Night - Wednesday Morning Snow Level
7500'
Wednesday Afternoon Snow Level
6000'
Wednesday Night Snow Level
4000'

* 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

Sunday Sunday
Hurricane Ridge 0.50 - 0.75 LT 0.25
Mt Baker Ski Area 0 - 2.00 0.75 - 1.00
Washington Pass 0 - 1.00 0 - 0.50
Stevens Pass 1.00 - 1.50 0 - 1.00
Snoqualmie Pass 0 - 1.50 1.00 - 1.50
Mission Ridge 0.25 - 0.50 LT 0.25
Crystal Mt 1.00 - 1.50 0.75 - 1.00
Paradise 2.00 - 3.00 0 - 1.50
White Pass 0 - 2.00 0 - 1.00
Mt Hood Meadows 0 - 0.50 0 - 1.00
0.50 - 0.75 0 - 1.50

Free Winds at 5000' (mph)

Hurricane Ridge Mt. Baker Stevens to Snoqualmie Pass Mt. Rainier Mt. Hood
Tuesday Afternoon SSW 15 - 25 SSW 25 - 35 SW 20 - 30 --- - SW 25 - 35
Tuesday Night SW 15 - 25 SW 20 - 30 SW 10 - 20 --- - SW 15 - 25
Wednesday Morning S 10 - 20 SW 5 - 15 WSW 5 - 15 --- - SW 20 - 30
Wednesday Afternoon SW 5 - 15 SW 10 - 20 WSW 5 - 15 --- - SW 25 - 35
Hurricane Ridge Elevation
Tuesday Afternoon SSW 15 - 25
Tuesday Night SW 15 - 25
Wednesday Morning S 10 - 20
Wednesday Afternoon SW 5 - 15
Wednesday Night WSW 15 - 25
Mt. Baker Elevation
Tuesday Afternoon SSW 25 - 35
Tuesday Night SW 20 - 30
Wednesday Morning SW 5 - 15
Wednesday Afternoon SW 10 - 20
Wednesday Night WSW 15 - 25
Stevens and Snoqualmie Pass Elevation
Tuesday Afternoon SW 20 - 30
Tuesday Night SW 10 - 20
Wednesday Morning WSW 5 - 15
Wednesday Afternoon WSW 5 - 15
Wednesday Night WSW 20 - 30
Mt. Rainier Elevation
Tuesday Afternoon --- -
Tuesday Night --- -
Wednesday Morning --- -
Wednesday Afternoon --- -
Wednesday Night --- -
Mt. Hood Elevation
Tuesday Afternoon SW 25 - 35
Tuesday Night SW 15 - 25
Wednesday Morning SW 20 - 30
Wednesday Afternoon SW 25 - 35
Wednesday Night WSW 25 - 35
Hurricane Ridge Direction - Speed
Tuesday Afternoon SSW 15 - 25
Tuesday Night SW 15 - 25
Wednesday Morning S 10 - 20
Wednesday Afternoon SW 5 - 15
Wednesday Night WSW 15 - 25
Mt. Baker Direction - Speed
Tuesday Afternoon SSW 25 - 35
Tuesday Night SW 20 - 30
Wednesday Morning SW 5 - 15
Wednesday Afternoon SW 10 - 20
Wednesday Night WSW 15 - 25
Stevens and Snoqualmie Pass Direction - Speed
Tuesday Afternoon SW 20 - 30
Tuesday Night SW 10 - 20
Wednesday Morning WSW 5 - 15
Wednesday Afternoon WSW 5 - 15
Wednesday Night WSW 20 - 30
Mt. Rainier Direction - Speed
Tuesday Afternoon --- -
Tuesday Night --- -
Wednesday Morning --- -
Wednesday Afternoon --- -
Wednesday Night --- -
Mt. Hood Direction - Speed
Tuesday Afternoon SW 25 - 35
Tuesday Night SW 15 - 25
Wednesday Morning SW 20 - 30
Wednesday Afternoon SW 25 - 35
Wednesday Night WSW 25 - 35

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 SW 35 - 45 SW 40 - 50 SW 35 - 45 --- - SW 40 - 50
Tuesday Night SW 30 - 40 SW 30 - 40 SW 30 - 40 --- - SW 45 - 55
Wednesday SW 25 - 35 SW 25 - 35 SW 25 - 35 --- - SW 40 - 50
Mt. Baker Direction - Speed
Tuesday Afternoon SW 35 - 45
Tuesday Night SW 30 - 40
Wednesday SW 25 - 35
Wednesday Night SW 20 - 30
Washington Pass Direction - Speed
Tuesday Afternoon SW 40 - 50
Tuesday Night SW 30 - 40
Wednesday SW 25 - 35
Wednesday Night SW 30 - 40
Stevens and Snoqualmie Pass Direction - Speed
Tuesday Afternoon SW 35 - 45
Tuesday Night SW 30 - 40
Wednesday SW 25 - 35
Wednesday Night SW 30 - 40
Mt. Rainier Direction - Speed
Tuesday Afternoon --- -
Tuesday Night --- -
Wednesday --- -
Wednesday Night --- -
Mt. Hood Direction - Speed
Tuesday Afternoon SW 40 - 50
Tuesday Night SW 45 - 55
Wednesday SW 40 - 50
Wednesday Night SW 45 - 55

Extended Weather Synopsis for Sunday night through Sunday

A weak front will brush the area on Thursday, mainly clipping the Olympics and north Cascades with light rain and snow and with spottier precipitation further south in the Washington Cascades. Mt. Hood will be on the southern periphery of the clouds and may squeak out some sunshine on Thursday. The front should lift north Thursday night leading to an overall drying and partial clearing trend. 

A developing low pressure system will quickly advance from off the Oregon Coast to the NW tip of the Olympic Peninsula Friday night. The details will surely change but the track and strength of this system look eerily similar to the low pressure system from last Thursday and Thursday night. The precipitation shield should quickly spread over the area Friday afternoon with a quick ramp up in snow levels, precipitation intensity and winds Friday night into Saturday morning. The trailing cold front should sweep through during the day on Saturday. 

Extended Snow/Freezing Levels

Mt. Baker Snoqualmie Pass Mt. Hood Easterly Flow *
Thursday - Thursday Night Snow Level 2000' - 3000' 2500' - 3500' 3000' - 4000'
Friday Snow Level 3000' - 4000' 3000' - 4000' 5500' - 6500'
Saturday Afternoon Snow Level 3000' - 4000' 3000' - 4000' 3500' - 4500'
Mt. Baker Elevation
Thursday - Thursday Night Snow Level
2000' - 3000'
Friday Snow Level
3000' - 4000'
Saturday Afternoon Snow Level
3000' - 4000'
Friday Night - Saturday Morning Snow Level
6000' - 7000'
(Easterly Flow *)
Snoqualmie Pass Elevation
Thursday - Thursday Night Snow Level
2500' - 3500'
Friday Snow Level
3000' - 4000'
Saturday Afternoon Snow Level
3000' - 4000'
Friday Night - Saturday Morning Snow Level
6000' - 7000'
(Easterly Flow *)
Mt. Hood Elevation
Thursday - Thursday Night Snow Level
3000' - 4000'
Friday Snow Level
5500' - 6500'
Saturday Afternoon Snow Level
3500' - 4500'
Friday Night - Saturday Morning Snow Level
7000' - 8000'
(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 Mar 14, 2017

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