Issued: 7:24 AM PST Monday, February 12, 2018
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 & Friday

A high amplitude ridge centered outside of 140W and extending north into the Yukon will lead to another dry day in the Pacific Northwest with NE flow aloft.  Clear skies will hold all day Monday and cold temperatures seen this morning will moderate somewhat during this afternoon. 

The upper level ridge will begin to flatten over the region on Tuesday as a frontal system begins to drop south across British Columbia.  Clouds will increase over the Washington Cascades and Olympics on Tuesday and crest level westerly winds will begin to pick up over the central and north Cascades.  Freezing levels will stay cool in the north but will transition further south, becoming mild for the south Washington Cascades and Mt. Hood Tuesday afternoon. 

Winds will increase further Tuesday night as the frontal system quickly sweeps through the area. Snow levels will drop rapidly as precipitation beings. Light amounts of new snowfall are expected by early Wednesday morning mainly across the west slopes of the Cascades.  

Weather Forecast

Olympics
Monday Mostly sunny.
Monday Night Mostly clear.
Tuesday Partly to mostly clear in the morning, becoming cloudy in the afternoon.
Washington Cascades near and west of the Crest including Stevens, Snoqualmie and White Passes
Monday Mostly sunny.
Monday Night Mostly clear.
Tuesday Partly to mostly clear in the morning, becoming cloudy north Cascades and partly cloudy south Cascades in the afternoon. Milder south Cascades including Crystal, Mt. Rainier and White Pass.
East Slopes of the Washington Cascades
Monday Mostly sunny.
Monday Night Mostly clear.
Tuesday Partly to mostly clear in the morning, becoming cloudy northeast Cascades and partly cloudy southeast Cascades in the afternoon. Increasing crest level winds northeast Cascades in the afternoon.
Mt. Hood
Monday Mostly sunny. Moderate N-NE winds in the alpine.
Monday Night Mostly clear.
Tuesday Mostly clear in the morning, becoming partly cloudy with periods of high clouds in the afternoon. Mild.

Snow/Freezing Level (ft)

Hurricane Ridge Mt. Baker Washington Pass Leavenworth Stevens Pass Snoqualmie Pass Mt. Rainier, Crystal & White Pass Mt. Hood
Monday Morning Freezing Level 1000' 0' 0' ' ' 500' ' 500'
Monday Afternoon Freezing Level 3500' 2000' 3500' ' ' 3000' ' 3000'
Monday Night Freezing Level 4000' 2000' 2000' ' ' 2000' ' 4000'
Tuesday Morning Freezing Level 4000' 2000' 2000' ' ' 1500' ' 5000'
Tuesday Afternoon Freezing Level 6000' 3500' 4500' ' ' 5000' ' 8500'
Hurricane Ridge Elevation
Monday Morning Freezing Level
1000'
Monday Afternoon Freezing Level
3500'
Monday Night Freezing Level
4000'
Tuesday Morning Freezing Level
4000'
Tuesday Afternoon Freezing Level
6000'
Tuesday Night Snow Level
2500'
Mt. Baker Elevation
Monday Morning Freezing Level
0'
Monday Afternoon Freezing Level
2000'
Monday Night Freezing Level
2000'
Tuesday Morning Freezing Level
2000'
Tuesday Afternoon Freezing Level
3500'
Tuesday Night Snow Level
1500'
Washington Pass Elevation
Monday Morning Freezing Level
0'
Monday Afternoon Freezing Level
3500'
Monday Night Freezing Level
2000'
Tuesday Morning Freezing Level
2000'
Tuesday Afternoon Freezing Level
4500'
Tuesday Night Snow Level
1500'
Leavenworth Elevation
Monday Morning Freezing Level
'
Monday Afternoon Freezing Level
'
Monday Night Freezing Level
'
Tuesday Morning Freezing Level
'
Tuesday Afternoon Freezing Level
'
Tuesday Night Snow Level
'
Stevens Pass Elevation
Monday Morning Freezing Level
'
Monday Afternoon Freezing Level
'
Monday Night Freezing Level
'
Tuesday Morning Freezing Level
'
Tuesday Afternoon Freezing Level
'
Tuesday Night Snow Level
'
Snoqualmie Pass Elevation
Monday Morning Freezing Level
500'
Monday Afternoon Freezing Level
3000'
Monday Night Freezing Level
2000'
Tuesday Morning Freezing Level
1500'
Tuesday Afternoon Freezing Level
5000'
Tuesday Night Snow Level
2000'
Mt. Rainier & Crystal Elevation
Monday Morning Freezing Level
'
Monday Afternoon Freezing Level
'
Monday Night Freezing Level
'
Tuesday Morning Freezing Level
'
Tuesday Afternoon Freezing Level
'
Tuesday Night Snow Level
'
Mt. Hood Elevation
Monday Morning Freezing Level
500'
Monday Afternoon Freezing Level
3000'
Monday Night Freezing Level
4000'
Tuesday Morning Freezing Level
5000'
Tuesday Afternoon Freezing Level
8500'
Tuesday Night Snow Level
2000'

* 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 0.25
Mt Baker Ski Area LT 0.10 0.25 - 0.50
Washington Pass LT 0.10 LT 0.25
Stevens Pass LT 0.10 LT 0.25
Snoqualmie Pass LT 0.10 LT 0.25
Mission Ridge LT 0.10 LT 0.10
Crystal Mt LT 0.10 LT 0.10
Paradise LT 0.10 LT 0.25
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
Monday Morning NE 5 - 15 NE 10 - 20 E 10 - 20 --- - ENE 10 - 20
Monday Afternoon VAR 0 - 10 VAR 0 - 10 VAR 0 - 10 --- - ENE 5 - 15
Monday Night VAR 0 - 10 W 0 - 10 NW 0 - 10 --- - VAR 0 - 10
Tuesday Morning SW 0 - 10 SW 0 - 10 W 0 - 10 --- - SW 0 - 10
Tuesday Afternoon WSW 5 - 15 SW 5 - 15 SW 5 - 15 --- - WSW 5 - 15
Hurricane Ridge Elevation
Monday Morning NE 5 - 15
Monday Afternoon VAR 0 - 10
Monday Night VAR 0 - 10
Tuesday Morning SW 0 - 10
Tuesday Afternoon WSW 5 - 15
Tuesday Night SW 20 - 30
Mt. Baker Elevation
Monday Morning NE 10 - 20
Monday Afternoon VAR 0 - 10
Monday Night W 0 - 10
Tuesday Morning SW 0 - 10
Tuesday Afternoon SW 5 - 15
Tuesday Night SSW 15 - 25
Stevens and Snoqualmie Pass Elevation
Monday Morning E 10 - 20
Monday Afternoon VAR 0 - 10
Monday Night NW 0 - 10
Tuesday Morning W 0 - 10
Tuesday Afternoon SW 5 - 15
Tuesday Night SW 20 - 30
Mt. Rainier Elevation
Monday Morning --- -
Monday Afternoon --- -
Monday Night --- -
Tuesday Morning --- -
Tuesday Afternoon --- -
Tuesday Night --- -
Mt. Hood Elevation
Monday Morning ENE 10 - 20
Monday Afternoon ENE 5 - 15
Monday Night VAR 0 - 10
Tuesday Morning SW 0 - 10
Tuesday Afternoon WSW 5 - 15
Tuesday Night WSW 15 - 30
Hurricane Ridge Direction - Speed
Monday Morning NE 5 - 15
Monday Afternoon VAR 0 - 10
Monday Night VAR 0 - 10
Tuesday Morning SW 0 - 10
Tuesday Afternoon WSW 5 - 15
Tuesday Night SW 20 - 30
Mt. Baker Direction - Speed
Monday Morning NE 10 - 20
Monday Afternoon VAR 0 - 10
Monday Night W 0 - 10
Tuesday Morning SW 0 - 10
Tuesday Afternoon SW 5 - 15
Tuesday Night SSW 15 - 25
Stevens and Snoqualmie Pass Direction - Speed
Monday Morning E 10 - 20
Monday Afternoon VAR 0 - 10
Monday Night NW 0 - 10
Tuesday Morning W 0 - 10
Tuesday Afternoon SW 5 - 15
Tuesday Night SW 20 - 30
Mt. Rainier Direction - Speed
Monday Morning --- -
Monday Afternoon --- -
Monday Night --- -
Tuesday Morning --- -
Tuesday Afternoon --- -
Tuesday Night --- -
Mt. Hood Direction - Speed
Monday Morning ENE 10 - 20
Monday Afternoon ENE 5 - 15
Monday Night VAR 0 - 10
Tuesday Morning SW 0 - 10
Tuesday Afternoon WSW 5 - 15
Tuesday Night WSW 15 - 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 NE 20 - 30 NE 15 - 25 NE 20 - 30 --- - N 20 - 30
Monday Afternoon NW 10 - 20 NNW 15 - 30 N 15 - 25 --- - NE 30 - 40
Monday Night NW 5 - 15 NW 5 - 15 NW 15 - 25 --- - NNE 15 - 30
Tuesday Morning WNW 20 - 30 W 15 - 25 NW 15 - 25 --- - NW 5 - 15
Tuesday Afternoon WSW 30 - 40 WSW 35 - 45 W 25 - 35 --- - WNW 15 - 25
Mt. Baker Direction - Speed
Monday Morning NE 20 - 30
Monday Afternoon NW 10 - 20
Monday Night NW 5 - 15
Tuesday Morning WNW 20 - 30
Tuesday Afternoon WSW 30 - 40
Tuesday Night WSW 30 - 40
Washington Pass Direction - Speed
Monday Morning NE 15 - 25
Monday Afternoon NNW 15 - 30
Monday Night NW 5 - 15
Tuesday Morning W 15 - 25
Tuesday Afternoon WSW 35 - 45
Tuesday Night WSW 35 - 45
Stevens and Snoqualmie Pass Direction - Speed
Monday Morning NE 20 - 30
Monday Afternoon N 15 - 25
Monday Night NW 15 - 25
Tuesday Morning NW 15 - 25
Tuesday Afternoon W 25 - 35
Tuesday Night WSW 40 - 50
Mt. Rainier Direction - Speed
Monday Morning --- -
Monday Afternoon --- -
Monday Night --- -
Tuesday Morning --- -
Tuesday Afternoon --- -
Tuesday Night --- -
Mt. Hood Direction - Speed
Monday Morning N 20 - 30
Monday Afternoon NE 30 - 40
Monday Night NNE 15 - 30
Tuesday Morning NW 5 - 15
Tuesday Afternoon WNW 15 - 25
Tuesday Night W 40 - 50

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 11, 2018

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.