Issued: 2:14 PM PST Monday, January 11, 2016
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 Monday & Sunday

Afternoon update: Adjusted Day 2 precipitation forecast and increased Tuesday evening winds

The upper level ridge that was over the area yesterday has shifted over the interior West and a weak front moving inland from the coastal waters will bring increasing clouds and generally light periods of rain and snow to the Olympics and Cascades today. High freezing levels over the west slopes and Olympics this morning will slowly lower today with the front. Colder air and low clouds for the east slopes and Cascade Passes will remain entrenched with little change for today. 

After some light showers Monday night, a stronger system extending form the parent upper low in the northeast Pacific will slowly move inland during the day Tuesday. The heaviest precipitation should be confined to the Olympics during the daylight hours with the front passing through Tuesday night. Snow levels west of the crest and away from the Cascade Passes should rise Tuesday afternoon ahead of the front. As has been the case often this winter, a secondary wave developing along the N-S oriented frontal band will direct some of the frontal system energy into northern California Tuesday night. Forecast models have been inconsistent with precipitation amounts with the latest runs leaning toward higher amounts. 

Weather Forecast

Olympics
Monday

Light rain and snow. Slight cooling through the day. 

Monday Night

Cloudy with a chance of light rain and snow showers. 

Tuesday

Light to moderate rain and snow developing in the morning. Slight warming trend during the day. 

Washington Cascades near and west of the crest including Stevens, Snoqualmie, and White Passes
Monday Morning

Increasing clouds with light rain and snow developing. 

Monday Afternoon

Light rain and snow. Slight cooling. 

Monday Night

Cloudy with a chance of light rain and snow showers. 

Tuesday

Light rain and snow developing by early afternoon. Slight warming away from the Cascade Passes. 

East slopes of the Washington Cascades
Monday Morning

Increasing clouds with periods of light rain and snow late morning. 

Monday Afternoon

Occasional light rain and snow. Slight warming trend. 

Monday Night

Cloudy with a chance of light rain and snow showers. 

Tuesday

Light rain and snow developing by early afternoon. 

Mt. Hood Area
Monday Morning

Increasing clouds with light rain and snow developing. 

Monday Afternoon

Light rain and snow. Slight cooling. 

Monday Night

Cloudy with a chance of light rain and snow showers. 

Tuesday

Cloudy. Light rain and snow developing in the afternoon. Slight warming trend during the day.

Snow/Freezing Level (ft)

Hurricane Ridge Mt. Baker Washington Pass Leavenworth Stevens Pass Snoqualmie Pass Mt. Rainier, Crystal & White Pass Mt. Hood
Monday Afternoon Snow Level * 4500' 3500' 3000' ' ' 3500' ' 5000'
Monday Night - Tuesday Morning Snow Level * 5000' 4000' 3500' ' ' 4000' ' 6000'
Tuesday Afternoon Snow Level * 5500' 5000' 3000' ' ' 3500' ' 7000'
Hurricane Ridge Elevation
Monday Afternoon Snow Level
4500'
(Easterly Flow *)
Monday Night - Tuesday Morning Snow Level
5000'
(Easterly Flow *)
Tuesday Afternoon Snow Level
5500'
(Easterly Flow *)
Tuesday Night Snow Level
5000'
(Easterly Flow *)
Mt. Baker Elevation
Monday Afternoon Snow Level
3500'
(Easterly Flow *)
Monday Night - Tuesday Morning Snow Level
4000'
(Easterly Flow *)
Tuesday Afternoon Snow Level
5000'
(Easterly Flow *)
Tuesday Night Snow Level
3500'
(Easterly Flow *)
Washington Pass Elevation
Monday Afternoon Snow Level
3000'
(Easterly Flow *)
Monday Night - Tuesday Morning Snow Level
3500'
(Easterly Flow *)
Tuesday Afternoon Snow Level
3000'
(Easterly Flow *)
Tuesday Night Snow Level
2500'
(Easterly Flow *)
Leavenworth Elevation
Monday Afternoon Snow Level
'
(Easterly Flow *)
Monday Night - Tuesday Morning Snow Level
'
(Easterly Flow *)
Tuesday Afternoon Snow Level
'
(Easterly Flow *)
Tuesday Night Snow Level
'
(Easterly Flow *)
Stevens Pass Elevation
Monday Afternoon Snow Level
'
(Easterly Flow *)
Monday Night - Tuesday Morning Snow Level
'
(Easterly Flow *)
Tuesday Afternoon Snow Level
'
(Easterly Flow *)
Tuesday Night Snow Level
'
(Easterly Flow *)
Snoqualmie Pass Elevation
Monday Afternoon Snow Level
3500'
(Easterly Flow *)
Monday Night - Tuesday Morning Snow Level
4000'
(Easterly Flow *)
Tuesday Afternoon Snow Level
3500'
(Easterly Flow *)
Tuesday Night Snow Level
3000'
(Easterly Flow *)
Mt. Rainier & Crystal Elevation
Monday Afternoon Snow Level
'
(Easterly Flow *)
Monday Night - Tuesday Morning Snow Level
'
(Easterly Flow *)
Tuesday Afternoon Snow Level
'
(Easterly Flow *)
Tuesday Night Snow Level
'
(Easterly Flow *)
Mt. Hood Elevation
Monday Afternoon Snow Level
5000'
(Easterly Flow *)
Monday Night - Tuesday Morning Snow Level
6000'
(Easterly Flow *)
Tuesday Afternoon Snow Level
7000'
(Easterly Flow *)
Tuesday Night Snow Level
6000'
(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

Sunday Sunday
Hurricane Ridge 0.25 - 0.50 0 - 1.00
Mt Baker Ski Area 0 - 0.50 1.00 - 1.50
Washington Pass 0.25 - 0.50 0 - 0.50
Stevens Pass LT 0.25 0.50 - 0.75
Snoqualmie Pass LT 0.25 0.75 - 1.00
Mission Ridge LT 0.10 0 - 0.50
Crystal Mt LT 0.25 1.00 - 1.50
Paradise 0.25 - 0.50 0 - 1.50
White Pass LT 0.10 0 - 0.50
Mt Hood Meadows LT 0.25 0 - 1.00
0.25 - 0.50 1.00 - 1.50

Free Winds at 5000' (mph)

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

Free Winds at 9000' (mph)

Mt. Baker Washington Pass Stevens to Snoqualmie Pass Mt. Rainier Mt. Hood
Monday SW 15 - 25 SW 10 - 20 SW 15 - 25 --- - SW 25 - 35
Monday Afternoon SW 20 - 30 SW 30 - 40 SW 25 - 40 --- - SW 30 - 40
Monday Night - Tuesday Morning SW 10 - 20 WSW 15 - 25 SW 25 - 35 --- - SW 20 - 30
Tuesday Afternoon SW 30 - 40 SW 20 - 30 SW 35 - 40 --- - SW 40 - 50
Mt. Baker Direction - Speed
Monday SW 15 - 25
Monday Afternoon SW 20 - 30
Monday Night - Tuesday Morning SW 10 - 20
Tuesday Afternoon SW 30 - 40
Tuesday Night SSW 35 - 45
Washington Pass Direction - Speed
Monday SW 10 - 20
Monday Afternoon SW 30 - 40
Monday Night - Tuesday Morning WSW 15 - 25
Tuesday Afternoon SW 20 - 30
Tuesday Night SW 45 - 55
Stevens and Snoqualmie Pass Direction - Speed
Monday SW 15 - 25
Monday Afternoon SW 25 - 40
Monday Night - Tuesday Morning SW 25 - 35
Tuesday Afternoon SW 35 - 40
Tuesday Night SW 50 - 60
Mt. Rainier Direction - Speed
Monday --- -
Monday Afternoon --- -
Monday Night - Tuesday Morning --- -
Tuesday Afternoon --- -
Tuesday Night --- -
Mt. Hood Direction - Speed
Monday SW 25 - 35
Monday Afternoon SW 30 - 40
Monday Night - Tuesday Morning SW 20 - 30
Tuesday Afternoon SW 40 - 50
Tuesday Night SW 50 - 70

Extended Weather Synopsis for Sunday night through Sunday

An open upper level trough should pass through Wednesday and Wednesday night bringing post-frontal showers and a generally cooler air mass into the region. A weather system on Thursday will slide SE into Oregon mainly affecting Mt. Hood and only delivering light amounts of precipitation to the south and central Washington Cascades. 

An upper level ridge will quickly build on Friday with shower activity quickly diminishing...but the ridge will be transitory as the next system should reach the area by Saturday morning. 

Extended Weather

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

Light to moderate rain and snow showers, potentially heaviest central Washington Cascades and south to Mt. Hood in the morning. Gradual cooling trend. 

Wednesday Night - Thursday Morning

Mostly cloudy with light rain and snow showers. 

Thursday Afternoon

Light rain and snow Mt. Hood and south Washington Cascades. Mostly cloudy with periods of light rain and snow Olympics and north Washington Cascades. 

Thursday Night - Friday

Scattered light rain and snow showers Thursday night diminishing during the day Friday with partial clearing. 

Extended Snow/Freezing Levels

Mt. Baker Snoqualmie Pass Mt. Hood Easterly Flow *
Wednesday - Wednesday Night Snow Level 3000' - 4000' 3000' - 4000' 3500' - 4500'
Mt. Baker Elevation
Wednesday - Wednesday Night Snow Level
3000' - 4000'
Thursday - Friday Snow Level
2000' - 3000'
(Easterly Flow *)
Snoqualmie Pass Elevation
Wednesday - Wednesday Night Snow Level
3000' - 4000'
Thursday - Friday Snow Level
2500' - 3500'
(Easterly Flow *)
Mt. Hood Elevation
Wednesday - Wednesday Night Snow Level
3500' - 4500'
Thursday - Friday Snow Level
2500' - 3500'
(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 11, 2016

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