Issued: 7:30 AM PST Monday, February 20, 2017
by Dennis D'Amico

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

Weather Synopsis for Monday & Thursday

A low pressure system off the central Oregon coast this morning will track NE across the southern Washington Cascades today. The precipitation shield associated with a warm front is currently affecting Mt. Hood and the south Washington Cascades. This area of precipitation should spread north into the central Washington Cascades, but only lightly brush the Olympics and north Cascades. 

Precipitation, winds and a warming trend will be most significant in the Mt. Hood area and south Washington Cascades on Monday. Mt. Hood may see snow levels bump up to 5000-5500 ft by late morning while they are in the warm sector before they slowly start to cool this afternoon. A switch to westerly winds will occur everywhere as the low passes to the east side of the Cascades this afternoon. 

Showers should quickly ease overnight before another low pressure system develops off the Oregon Coast and tracks to the NE on Tuesday.  Most forecast models have this low tracking further south and mainly affecting Mt. Hood.  However, the European model moves the precipitation shield further north, similar to Monday's system. The Day 2 precipitation forecast reflects the GFS/WRF track for now. 

A cold upper level trough is forecast to move over PNW starting Tuesday afternoon and snow levels should begin to drop in earnest later Tuesday afternoon into Tuesday night with light snow showers continuing into Wednesday.  

Weather Forecast

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

Light to occasionally moderate rain and snow south Cascades. Light rain and snow developing central and north Cascades. 

Monday Afternoon - Monday Evening

Moderate rain and snow south Cascades becoming showers in the afternoon. Light rain and snow central and north Cascades becoming showers in the afternoon. Slight warming trend peaking in the afternoon. Strong alpine winds south Washington Cascades. 

Monday Night

Mostly cloudy with scattered light showers. 

Tuesday

Cloudy with ceilings lowering in the afternoon. Periods of light rain and snow developing mid-day, mainly central and south Cascades.  

Olympics
Monday

Periods of light rain and snow developing in the morning becoming light rain and snow showers in the afternoon. Slight warming trend peaking in the early afternoon.  

Monday Night

Mostly cloudy with scattered light showers. 

Tuesday

Cloudy with ceilings lowering in the afternoon. Periods of very light rain and snow developing mid-day.  

East slopes of the Washington Cascades
Monday Morning

Light to occasionally moderate rain and snow southeast Cascades. Light rain and snow developing central-east and northeast Cascades. 

Monday Afternoon - Monday Evening

Light to moderate rain and snow southeast Cascades becoming showers in the afternoon. Light rain and snow central-east and northeast Cascades becoming showers in the afternoon. Slight warming trend peaking in the afternoon. Strong alpine winds southeast Washington Cascades. 

Monday Night

Mostly cloudy with isolated light showers. 

Tuesday

Cloudy with ceilings lowering in the afternoon. Periods of light rain and snow developing mid-day, mainly central-east and southeast Cascades.  

Mt. Hood Area
Monday Morning

Periods of light to occasionally moderate rain and snow. Warming trend. 

Monday Afternoon - Monday Evening

Moderate rain and snow becoming showers in the afternoon. Strong alpine winds. 

Monday Night

Mostly cloudy with scattered light showers. 

Tuesday

Light to moderate rain and snow.  

Snow/Freezing Level (ft)

Hurricane Ridge Mt. Baker Washington Pass Leavenworth Stevens Pass Snoqualmie Pass Mt. Rainier, Crystal & White Pass Mt. Hood
Monday Morning Snow Level 2500' 2000' 2000' ' ' 2500' ' 3500'
Monday Mid-day Snow Level 3000' 2500' 2500' ' ' 2500' ' 5000'
Monday Afternoon Snow Level 3500' 3500' 4000' ' ' 3000' ' 4500'
Monday Night - Tuesday Morning Snow Level 2500' 1500' 1500' ' ' 2500' ' 4000'
Tuesday Afternoon Snow Level 2000' 2000' 2500' ' ' 2500' ' 3000'
Hurricane Ridge Elevation
Monday Morning Snow Level
2500'
Monday Mid-day Snow Level
3000'
Monday Afternoon Snow Level
3500'
Monday Night - Tuesday Morning Snow Level
2500'
Tuesday Afternoon Snow Level
2000'
Tuesday Night Snow Level
1000'
Mt. Baker Elevation
Monday Morning Snow Level
2000'
Monday Mid-day Snow Level
2500'
Monday Afternoon Snow Level
3500'
Monday Night - Tuesday Morning Snow Level
1500'
Tuesday Afternoon Snow Level
2000'
Tuesday Night Snow Level
1000'
Washington Pass Elevation
Monday Morning Snow Level
2000'
Monday Mid-day Snow Level
2500'
Monday Afternoon Snow Level
4000'
Monday Night - Tuesday Morning Snow Level
1500'
Tuesday Afternoon Snow Level
2500'
Tuesday Night Snow Level
500'
Leavenworth Elevation
Monday Morning Snow Level
'
Monday Mid-day Snow Level
'
Monday Afternoon Snow Level
'
Monday Night - Tuesday Morning Snow Level
'
Tuesday Afternoon Snow Level
'
Tuesday Night Snow Level
'
Stevens Pass Elevation
Monday Morning Snow Level
'
Monday Mid-day Snow Level
'
Monday Afternoon Snow Level
'
Monday Night - Tuesday Morning Snow Level
'
Tuesday Afternoon Snow Level
'
Tuesday Night Snow Level
'
Snoqualmie Pass Elevation
Monday Morning Snow Level
2500'
Monday Mid-day Snow Level
2500'
Monday Afternoon Snow Level
3000'
Monday Night - Tuesday Morning Snow Level
2500'
Tuesday Afternoon Snow Level
2500'
Tuesday Night Snow Level
1000'
Mt. Rainier & Crystal Elevation
Monday Morning Snow Level
'
Monday Mid-day Snow Level
'
Monday Afternoon Snow Level
'
Monday Night - Tuesday Morning Snow Level
'
Tuesday Afternoon Snow Level
'
Tuesday Night Snow Level
'
Mt. Hood Elevation
Monday Morning Snow Level
3500'
Monday Mid-day Snow Level
5000'
Monday Afternoon Snow Level
4500'
Monday Night - Tuesday Morning Snow Level
4000'
Tuesday Afternoon Snow Level
3000'
Tuesday Night Snow Level
1500'

* 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

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

Free Winds at 5000' (mph)

Hurricane Ridge Mt. Baker Stevens to Snoqualmie Pass Mt. Rainier Mt. Hood
Monday Morning E 0 - 10 SE 0 - 10 ESE 5 - 15 --- - S 15 - 25
Monday Afternoon W 5 - 15 W 0 - 10 W 5 - 15 --- - WSW 25 - 40
Monday Night - Tuesday Morning N 0 - 10 VAR 0 - 10 VAR 0 - 10 --- - E 0 - 10
Hurricane Ridge Elevation
Monday Morning E 0 - 10
Monday Afternoon W 5 - 15
Monday Night - Tuesday Morning N 0 - 10
Tuesday Afternoon - Tuesday Night NW 10 - 20
Mt. Baker Elevation
Monday Morning SE 0 - 10
Monday Afternoon W 0 - 10
Monday Night - Tuesday Morning VAR 0 - 10
Tuesday Afternoon - Tuesday Night W 5 - 15
Stevens and Snoqualmie Pass Elevation
Monday Morning ESE 5 - 15
Monday Afternoon W 5 - 15
Monday Night - Tuesday Morning VAR 0 - 10
Tuesday Afternoon - Tuesday Night WNW 10 - 20
Mt. Rainier Elevation
Monday Morning --- -
Monday Afternoon --- -
Monday Night - Tuesday Morning --- -
Tuesday Afternoon - Tuesday Night --- -
Mt. Hood Elevation
Monday Morning S 15 - 25
Monday Afternoon WSW 25 - 40
Monday Night - Tuesday Morning E 0 - 10
Tuesday Afternoon - Tuesday Night NW 20 - 30
Hurricane Ridge Direction - Speed
Monday Morning E 0 - 10
Monday Afternoon W 5 - 15
Monday Night - Tuesday Morning N 0 - 10
Tuesday Afternoon - Tuesday Night NW 10 - 20
Mt. Baker Direction - Speed
Monday Morning SE 0 - 10
Monday Afternoon W 0 - 10
Monday Night - Tuesday Morning VAR 0 - 10
Tuesday Afternoon - Tuesday Night W 5 - 15
Stevens and Snoqualmie Pass Direction - Speed
Monday Morning ESE 5 - 15
Monday Afternoon W 5 - 15
Monday Night - Tuesday Morning VAR 0 - 10
Tuesday Afternoon - Tuesday Night WNW 10 - 20
Mt. Rainier Direction - Speed
Monday Morning --- -
Monday Afternoon --- -
Monday Night - Tuesday Morning --- -
Tuesday Afternoon - Tuesday Night --- -
Mt. Hood Direction - Speed
Monday Morning S 15 - 25
Monday Afternoon WSW 25 - 40
Monday Night - Tuesday Morning E 0 - 10
Tuesday Afternoon - Tuesday Night NW 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 Morning SW 10 - 20 SW 5 - 15 SW 15 - 30 --- - SW 25 - 35
Monday Afternoon W 10 - 20 W 10 - 20 WSW 25 - 35 --- - SW 50 - 70
Monday Night - Tuesday Morning SW 10 - 20 SW 0 - 10 SW 5 - 15 --- - S 15 - 25
Tuesday Afternoon W 10 - 20 W 5 - 15 NW 15 - 25 --- - NW 25 - 35
Mt. Baker Direction - Speed
Monday Morning SW 10 - 20
Monday Afternoon W 10 - 20
Monday Night - Tuesday Morning SW 10 - 20
Tuesday Afternoon W 10 - 20
Tuesday Night W 15 - 25
Washington Pass Direction - Speed
Monday Morning SW 5 - 15
Monday Afternoon W 10 - 20
Monday Night - Tuesday Morning SW 0 - 10
Tuesday Afternoon W 5 - 15
Tuesday Night W 20 - 30
Stevens and Snoqualmie Pass Direction - Speed
Monday Morning SW 15 - 30
Monday Afternoon WSW 25 - 35
Monday Night - Tuesday Morning SW 5 - 15
Tuesday Afternoon NW 15 - 25
Tuesday Night W 25 - 35
Mt. Rainier Direction - Speed
Monday Morning --- -
Monday Afternoon --- -
Monday Night - Tuesday Morning --- -
Tuesday Afternoon --- -
Tuesday Night --- -
Mt. Hood Direction - Speed
Monday Morning SW 25 - 35
Monday Afternoon SW 50 - 70
Monday Night - Tuesday Morning S 15 - 25
Tuesday Afternoon NW 25 - 35
Tuesday Night W 30 - 40

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.

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

Previous forecast from Feb 19, 2017

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