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 & 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 the 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 warm further to the south, becoming mild for the south Washington Cascades and Mt. Hood on Tuesday afternoon.
Winds will increase further Tuesday night as the frontal system quickly sweeps through the area. Snow levels will drop rapidly as precipitation begins late in the evening. 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. |
| Tuesday Night | Light snow developing in the evening. Increasing winds. Strong cooling. |
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. |
| Tuesday Night | Rapid cooling with light snow developing overnight from north to south. Increasing winds. |
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. |
| Tuesday Night | Rapid cooling with light snow developing overnight from north to south mainly near the Cascades crest. Increasing winds. |
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. |
| Tuesday Night | Rapid cooling with light snow developing after midnight. Increasing winds overnight. |
Issued: 2:48 PM PST Monday, February 12, 2018
Snow/Freezing Level (ft)
| Hurricane Ridge | Mt. Baker | Washington Pass | Leavenworth | Stevens Pass | Snoqualmie Pass | Mt. Rainier, Crystal & White Pass | Mt. Hood | ||
|---|---|---|---|---|---|---|---|---|---|
| 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 | 6500' | 3500' | 5000' | ' | ' | 6000' | ' | 9000' |
| Tuesday Night | Snow Level | 2500' | 1500' | 1500' | ' | ' | 2000' | ' | 2000' |
| Hurricane Ridge | Elevation |
|---|---|
| Monday Afternoon |
Freezing Level 3500' |
| Monday Night |
Freezing Level 4000' |
| Tuesday Morning |
Freezing Level 4000' |
| Tuesday Afternoon |
Freezing Level 6500' |
| Tuesday Night |
Snow Level 2500' |
| Mt. Baker | Elevation |
|---|---|
| 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 Afternoon |
Freezing Level 3500' |
| Monday Night |
Freezing Level 2000' |
| Tuesday Morning |
Freezing Level 2000' |
| Tuesday Afternoon |
Freezing Level 5000' |
| Tuesday Night |
Snow Level 1500' |
| Leavenworth | Elevation |
|---|---|
| Monday Afternoon |
Freezing Level ' |
| Monday Night |
Freezing Level ' |
| Tuesday Morning |
Freezing Level ' |
| Tuesday Afternoon |
Freezing Level ' |
| Tuesday Night |
Snow Level ' |
| Stevens Pass | Elevation |
|---|---|
| Monday Afternoon |
Freezing Level ' |
| Monday Night |
Freezing Level ' |
| Tuesday Morning |
Freezing Level ' |
| Tuesday Afternoon |
Freezing Level ' |
| Tuesday Night |
Snow Level ' |
| Snoqualmie Pass | Elevation |
|---|---|
| Monday Afternoon |
Freezing Level 3000' |
| Monday Night |
Freezing Level 2000' |
| Tuesday Morning |
Freezing Level 1500' |
| Tuesday Afternoon |
Freezing Level 6000' |
| Tuesday Night |
Snow Level 2000' |
| Mt. Rainier & Crystal | Elevation |
|---|---|
| Monday Afternoon |
Freezing Level ' |
| Monday Night |
Freezing Level ' |
| Tuesday Morning |
Freezing Level ' |
| Tuesday Afternoon |
Freezing Level ' |
| Tuesday Night |
Snow Level ' |
| Mt. Hood | Elevation |
|---|---|
| Monday Afternoon |
Freezing Level 3000' |
| Monday Night |
Freezing Level 4000' |
| Tuesday Morning |
Freezing Level 5000' |
| Tuesday Afternoon |
Freezing Level 9000' |
| 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 0.25 |
| Mt Hood Meadows | LT 0.10 | LT 0.10 |
| Timberline | LT 0.10 | LT 0.10 |
LT = less than; WE or Water equivalent is the liquid water equivalent of melted snow in hundredths of inches. As a rough approximation 1 inch of snow = about .10 inches WE, or 10 inches of snow = about 1 inch WE.
Issued: 2:48 PM PST Monday, February 12, 2018
Free Winds at 5000' (mph)
| Hurricane Ridge | Mt. Baker | Stevens to Snoqualmie Pass | Mt. Rainier | Mt. Hood | |
|---|---|---|---|---|---|
| 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 |
| Tuesday Night | SW 20 - 30 | SSW 15 - 25 | SW 20 - 30 | --- - | WSW 15 - 30 |
| Hurricane Ridge | Elevation |
|---|---|
| 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 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 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 Afternoon | --- - |
| Monday Night | --- - |
| Tuesday Morning | --- - |
| Tuesday Afternoon | --- - |
| Tuesday Night | --- - |
| Mt. Hood | Elevation |
|---|---|
| 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 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 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 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 Afternoon | --- - |
| Monday Night | --- - |
| Tuesday Morning | --- - |
| Tuesday Afternoon | --- - |
| Tuesday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| 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 Afternoon | NW 10 - 20 | NNW 15 - 30 | N 15 - 25 | --- - | NE 30 - 40 |
| Monday Night | NW 5 - 15 | NW 10 - 20 | NW 10 - 20 | --- - | 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 |
| Tuesday Night | WSW 30 - 40 | WSW 35 - 45 | WSW 40 - 50 | --- - | W 40 - 50 |
| Mt. Baker | Direction - Speed |
|---|---|
| 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 Afternoon | NNW 15 - 30 |
| Monday Night | NW 10 - 20 |
| Tuesday Morning | W 15 - 25 |
| Tuesday Afternoon | WSW 35 - 45 |
| Tuesday Night | WSW 35 - 45 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Monday Afternoon | N 15 - 25 |
| Monday Night | NW 10 - 20 |
| Tuesday Morning | NW 15 - 25 |
| Tuesday Afternoon | W 25 - 35 |
| Tuesday Night | WSW 40 - 50 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Monday Afternoon | --- - |
| Monday Night | --- - |
| Tuesday Morning | --- - |
| Tuesday Afternoon | --- - |
| Tuesday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| 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.
Issued: 2:48 PM PST Monday, February 12, 2018
Extended Weather Synopsis for Friday night through Friday
The frontal boundary will pass through the Cascades early Wednesday morning and as the trailing upper trough axis digs into central Oregon Wednesday afternoon, the flow aloft will once again turn NW. Snow showers at cool snow levels on Wednesday will taper off for the northwest and central-west Cascades, but continue for the southwest Washington Cascades and Mt. Hood. The trough will quickly pass into the Intermountain West Wednesday night with showers shutting off overnight.
The broad upper level ridge will assume it's familiar position over the last several weeks offshore, with systems coursing over the ridge and through the Pacific Northwest in NW flow aloft. Weak warm frontal moisture should bring light snow to most of the Washington Cascades and Olympics by Thursday afternoon with precipitation increasing further overnight. This system looks largely to miss Mt. Hood and once again favors the west slopes of the Washington Cascades. Post-frontal showers will continue Friday, but the ridge will begin to shift the jet stream further north allowing snow levels to rise during the day.
Extended Weather
Olympics, Washington Cascades and Mt. Hood Area
Extended Snow/Freezing Levels
| Mt. Baker | Snoqualmie Pass | Mt. Hood | Easterly Flow * | ||
|---|---|---|---|---|---|
| Wednesday | Snow Level | 1500' - 2500' | 1500' - 2500' | 2000' - 3000' | |
| Wednesday Night | Snow Level | 0' - 1000' | 500' - 1500' | 1500' - 2500' | |
| Thursday | Snow Level | 500' - 1500' | 500' - 1500' | 1000' - 2000' | |
| Thursday Night | Snow Level | 1500' - 2500' | 1500' - 2500' | 2000' - 3000' | |
| Friday | Snow Level | 3000' - 4000' | 3000' - 4000' | 3000' - 4000' |
| Mt. Baker | Elevation |
|---|---|
| Wednesday |
Snow Level 1500' - 2500' |
| Wednesday Night |
Snow Level 0' - 1000' |
| Thursday |
Snow Level 500' - 1500' |
| Thursday Night |
Snow Level 1500' - 2500' |
| Friday |
Snow Level 3000' - 4000' |
| Snoqualmie Pass | Elevation |
|---|---|
| Wednesday |
Snow Level 1500' - 2500' |
| Wednesday Night |
Snow Level 500' - 1500' |
| Thursday |
Snow Level 500' - 1500' |
| Thursday Night |
Snow Level 1500' - 2500' |
| Friday |
Snow Level 3000' - 4000' |
| Mt. Hood | Elevation |
|---|---|
| Wednesday |
Snow Level 2000' - 3000' |
| Wednesday Night |
Snow Level 1500' - 2500' |
| Thursday |
Snow Level 1000' - 2000' |
| Thursday Night |
Snow Level 2000' - 3000' |
| Friday |
Snow Level 3000' - 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.
Jump to: Weather Forecast I Snow/Freezing Level I Precipitation I Free Winds 5k I Free Winds 9k I Extended Weather
Previous forecast from Feb 12, 2018
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