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 & Friday
The Pacific Northwest will remain in cold northerly flow aloft for the next several days. Weak disturbances are expected to form on the downstream side of the ridge and progress from north to south over the next few days. These weak disturbances are likely to brush the forecast area at times, increasing cloud cover, and providing periods of light snow with no substantial accumulations.
Temperatures on Wednesday afternoon are cold, mostly in the 10's and low 20's.
A weak disturbance Tuesday has split with the majority of the energy going south off the coast of southern Oregon and a smaller chunk of energy forming a small re-circulation spreading light snowfall, mainly south of Snoqualmie Pass, with clear skies north of Stevens Pass. The snow is cold and low density with very little wind and precipitation is not being recorded well by the weather stations. Mt. Hood is expected to be favored during this event.
Precipitation from Tuesday's weak disturbance should end from north to south Tuesday night with skies clearing before midnight over the Olympics and north to central Cascades, and clearing after midnight in the south Cascades, and in the early morning hours for Mt. Hood.
High clouds will lower and thicken from northwest to southeast as a shortwave open trough and weak surface low approaches on Wednesday. The trough should arrive in the late afternoon and evening hours, bringing some light westerly flow out ahead of it and N-NE flow after the low passes to the south.. Light snow is likely to fall, mainly over the Olympics during the late afternoon hours and Wednesday night, particularly as the N-NE flow creates up-slope flow, enhancing the precipitation on the north slope of the Olympics.
Weather Forecast
Olympics
| Tuesday | Clouds giving way to sunshine. |
| Tuesday Night | Clear and cold. |
| Wednesday | Clouds lowering and thickening. |
| Wednesday Night | Periods of light snow. |
Washington Cascades near and west of the Crest including Stevens, Snoqualmie and White Passes
| Tuesday | Periods of light snow, mainly from Mt. Rainier southward. Mostly sunny north of Stevens pass. |
| Tuesday Night | Skies becoming clear from north to south. |
| Wednesday | Clouds lowering and thickening. |
| Wednesday Night | Cloudy with a chance of snow flurries. |
East Slopes of the Washington Cascades
| Tuesday | Periods of light snow southern part. Mostly sunny north of Stevens pass. |
| Tuesday Night | Skies becoming clear from north to south. |
| Wednesday | Clear in the morning with clouds lowering and thickening. |
| Wednesday Night | Mostly cloudy. |
Mt. Hood
| Tuesday | Light snow. |
| Tuesday Night | Light snow decreasing after midnight with clearing possible by morning. |
| Wednesday | Mostly cloudy with mid to high-level clouds. |
| Wednesday Night | Cloudy with a chance of light snow after midnight. |
Issued: 1:58 PM PST Tuesday, February 20, 2018
Snow/Freezing Level (ft)
| Hurricane Ridge | Mt. Baker | Washington Pass | Leavenworth | Stevens Pass | Snoqualmie Pass | Mt. Rainier, Crystal & White Pass | Mt. Hood | ||
|---|---|---|---|---|---|---|---|---|---|
| Tuesday Morning | Snow Level | 0' | 0' | 0' | ' | ' | 0' | ' | 0' |
| Tuesday Afternoon | Snow Level * | 0' | 0' | 0' | ' | ' | 0' | ' | 1000' |
| Tuesday Night | Snow Level * | 0' | 0' | 0' | ' | ' | 0' | ' | 0' |
| Wednesday Morning | Freezing Level * | 500' | 500' | 500' | ' | ' | 500' | ' | 500' |
| Wednesday Afternoon | Freezing Level | 500' | 500' | 500' | ' | ' | 500' | ' | 1000' |
| Wednesday Night | Snow Level * | 0' | 0' | 0' | ' | ' | 0' | ' | 0' |
| Hurricane Ridge | Elevation |
|---|---|
| Tuesday Morning |
Snow Level 0' |
| Tuesday Afternoon |
Snow Level 0' (Easterly Flow *) |
| Tuesday Night |
Snow Level 0' (Easterly Flow *) |
| Wednesday Morning |
Freezing Level 500' (Easterly Flow *) |
| Wednesday Afternoon |
Freezing Level 500' |
| Wednesday Night |
Snow Level 0' (Easterly Flow *) |
| Mt. Baker | Elevation |
|---|---|
| Tuesday Morning |
Snow Level 0' |
| Tuesday Afternoon |
Snow Level 0' (Easterly Flow *) |
| Tuesday Night |
Snow Level 0' (Easterly Flow *) |
| Wednesday Morning |
Freezing Level 500' (Easterly Flow *) |
| Wednesday Afternoon |
Freezing Level 500' |
| Wednesday Night |
Snow Level 0' (Easterly Flow *) |
| Washington Pass | Elevation |
|---|---|
| Tuesday Morning |
Snow Level 0' |
| Tuesday Afternoon |
Snow Level 0' (Easterly Flow *) |
| Tuesday Night |
Snow Level 0' (Easterly Flow *) |
| Wednesday Morning |
Freezing Level 500' (Easterly Flow *) |
| Wednesday Afternoon |
Freezing Level 500' |
| Wednesday Night |
Snow Level 0' (Easterly Flow *) |
| Leavenworth | Elevation |
|---|---|
| Tuesday Morning |
Snow Level ' |
| Tuesday Afternoon |
Snow Level ' (Easterly Flow *) |
| Tuesday Night |
Snow Level ' (Easterly Flow *) |
| Wednesday Morning |
Freezing Level ' (Easterly Flow *) |
| Wednesday Afternoon |
Freezing Level ' |
| Wednesday Night |
Snow Level ' (Easterly Flow *) |
| Stevens Pass | Elevation |
|---|---|
| Tuesday Morning |
Snow Level ' |
| Tuesday Afternoon |
Snow Level ' (Easterly Flow *) |
| Tuesday Night |
Snow Level ' (Easterly Flow *) |
| Wednesday Morning |
Freezing Level ' (Easterly Flow *) |
| Wednesday Afternoon |
Freezing Level ' |
| Wednesday Night |
Snow Level ' (Easterly Flow *) |
| Snoqualmie Pass | Elevation |
|---|---|
| Tuesday Morning |
Snow Level 0' |
| Tuesday Afternoon |
Snow Level 0' (Easterly Flow *) |
| Tuesday Night |
Snow Level 0' (Easterly Flow *) |
| Wednesday Morning |
Freezing Level 500' (Easterly Flow *) |
| Wednesday Afternoon |
Freezing Level 500' |
| Wednesday Night |
Snow Level 0' (Easterly Flow *) |
| Mt. Rainier & Crystal | Elevation |
|---|---|
| Tuesday Morning |
Snow Level ' |
| Tuesday Afternoon |
Snow Level ' (Easterly Flow *) |
| Tuesday Night |
Snow Level ' (Easterly Flow *) |
| Wednesday Morning |
Freezing Level ' (Easterly Flow *) |
| Wednesday Afternoon |
Freezing Level ' |
| Wednesday Night |
Snow Level ' (Easterly Flow *) |
| Mt. Hood | Elevation |
|---|---|
| Tuesday Morning |
Snow Level 0' |
| Tuesday Afternoon |
Snow Level 1000' (Easterly Flow *) |
| Tuesday Night |
Snow Level 0' (Easterly Flow *) |
| Wednesday Morning |
Freezing Level 500' (Easterly Flow *) |
| Wednesday Afternoon |
Freezing Level 1000' |
| Wednesday Night |
Snow Level 0' (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
| Friday | Friday | |
|---|---|---|
| Hurricane Ridge | LT 0.10 | LT 0.10 |
| Mt Baker Ski Area | LT 0.10 | LT 0.10 |
| Washington Pass | LT 0.10 | LT 0.10 |
| Stevens Pass | LT 0.10 | LT 0.10 |
| Snoqualmie Pass | LT 0.10 | LT 0.10 |
| Mission Ridge | LT 0.10 | LT 0.10 |
| Crystal Mt | LT 0.10 | LT 0.10 |
| Paradise | LT 0.25 | LT 0.10 |
| White Pass | LT 0.25 | LT 0.10 |
| Mt Hood Meadows | LT 0.25 | LT 0.10 |
| Timberline | 0.25 - 0.50 | 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: 1:58 PM PST Tuesday, February 20, 2018
Free Winds at 5000' (mph)
| Hurricane Ridge | Mt. Baker | Stevens to Snoqualmie Pass | Mt. Rainier | Mt. Hood | |
|---|---|---|---|---|---|
| Tuesday Afternoon | NE 5 - 15 | NNE 5 - 15 | VAR 0 - 10 | --- - | VAR 0 - 10 |
| Tuesday Night | NE 10 - 20 | NE 10 - 20 | E 5 - 15 | --- - | E 10 - 20 |
| Wednesday Morning | W 10 - 20 | SSW 5 - 15 | S 5 - 15 | --- - | ESE 5 - 15 |
| Wednesday Afternoon | W 5 - 15 | VAR 0 - 10 | W 5 - 15 | --- - | W 5 - 15 |
| Wednesday Night | NE 10 - 20 | NE 5 - 15 | VAR 0 - 10 | --- - | ENE 5 - 15 |
| Hurricane Ridge | Elevation |
|---|---|
| Tuesday Afternoon | NE 5 - 15 |
| Tuesday Night | NE 10 - 20 |
| Wednesday Morning | W 10 - 20 |
| Wednesday Afternoon | W 5 - 15 |
| Wednesday Night | NE 10 - 20 |
| Mt. Baker | Elevation |
|---|---|
| Tuesday Afternoon | NNE 5 - 15 |
| Tuesday Night | NE 10 - 20 |
| Wednesday Morning | SSW 5 - 15 |
| Wednesday Afternoon | VAR 0 - 10 |
| Wednesday Night | NE 5 - 15 |
| Stevens and Snoqualmie Pass | Elevation |
|---|---|
| Tuesday Afternoon | VAR 0 - 10 |
| Tuesday Night | E 5 - 15 |
| Wednesday Morning | S 5 - 15 |
| Wednesday Afternoon | W 5 - 15 |
| Wednesday Night | VAR 0 - 10 |
| Mt. Rainier | Elevation |
|---|---|
| Tuesday Afternoon | --- - |
| Tuesday Night | --- - |
| Wednesday Morning | --- - |
| Wednesday Afternoon | --- - |
| Wednesday Night | --- - |
| Mt. Hood | Elevation |
|---|---|
| Tuesday Afternoon | VAR 0 - 10 |
| Tuesday Night | E 10 - 20 |
| Wednesday Morning | ESE 5 - 15 |
| Wednesday Afternoon | W 5 - 15 |
| Wednesday Night | ENE 5 - 15 |
| Hurricane Ridge | Direction - Speed |
|---|---|
| Tuesday Afternoon | NE 5 - 15 |
| Tuesday Night | NE 10 - 20 |
| Wednesday Morning | W 10 - 20 |
| Wednesday Afternoon | W 5 - 15 |
| Wednesday Night | NE 10 - 20 |
| Mt. Baker | Direction - Speed |
|---|---|
| Tuesday Afternoon | NNE 5 - 15 |
| Tuesday Night | NE 10 - 20 |
| Wednesday Morning | SSW 5 - 15 |
| Wednesday Afternoon | VAR 0 - 10 |
| Wednesday Night | NE 5 - 15 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Tuesday Afternoon | VAR 0 - 10 |
| Tuesday Night | E 5 - 15 |
| Wednesday Morning | S 5 - 15 |
| Wednesday Afternoon | W 5 - 15 |
| Wednesday Night | VAR 0 - 10 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Tuesday Afternoon | --- - |
| Tuesday Night | --- - |
| Wednesday Morning | --- - |
| Wednesday Afternoon | --- - |
| Wednesday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| Tuesday Afternoon | VAR 0 - 10 |
| Tuesday Night | E 10 - 20 |
| Wednesday Morning | ESE 5 - 15 |
| Wednesday Afternoon | W 5 - 15 |
| Wednesday Night | ENE 5 - 15 |
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 | N 5 - 15 | NW 5 - 15 | W 10 - 20 | --- - | W 20 - 30 |
| Tuesday Night | N 10 - 20 | NNW 10 - 20 | N 10 - 20 | --- - | WNW 15 - 25 |
| Wednesday Morning | W 10 - 20 | W 10 - 20 | W 15 - 25 | --- - | NW 10 - 20 |
| Wednesday Afternoon | W 5 - 15 | W 5 - 15 | W 15 - 25 | --- - | W 15 - 25 |
| Wednesday Night | NNE 20 - 30 | N 20 - 30 | N 15 - 25 | --- - | N 15 - 25 |
| Mt. Baker | Direction - Speed |
|---|---|
| Tuesday Afternoon | N 5 - 15 |
| Tuesday Night | N 10 - 20 |
| Wednesday Morning | W 10 - 20 |
| Wednesday Afternoon | W 5 - 15 |
| Wednesday Night | NNE 20 - 30 |
| Washington Pass | Direction - Speed |
|---|---|
| Tuesday Afternoon | NW 5 - 15 |
| Tuesday Night | NNW 10 - 20 |
| Wednesday Morning | W 10 - 20 |
| Wednesday Afternoon | W 5 - 15 |
| Wednesday Night | N 20 - 30 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Tuesday Afternoon | W 10 - 20 |
| Tuesday Night | N 10 - 20 |
| Wednesday Morning | W 15 - 25 |
| Wednesday Afternoon | W 15 - 25 |
| Wednesday Night | N 15 - 25 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Tuesday Afternoon | --- - |
| Tuesday Night | --- - |
| Wednesday Morning | --- - |
| Wednesday Afternoon | --- - |
| Wednesday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| Tuesday Afternoon | W 20 - 30 |
| Tuesday Night | WNW 15 - 25 |
| Wednesday Morning | NW 10 - 20 |
| Wednesday Afternoon | W 15 - 25 |
| Wednesday Night | N 15 - 25 |
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: 1:58 PM PST Tuesday, February 20, 2018
Extended Weather Synopsis for Friday night through Friday
N-NW flow will continue for the duration of the long-range forecast, keeping cold weather over the forecast area with disturbances continuing to ride down the back of an off-shore high pressure.
The trough broadens with a closed circulation spinning and sagging south over the southern part of the forecast area on Thursday morning. This will keep scattered clouds and a chance of some light snow for some locations in the morning, clearing from north to south by afternoon.
On Thursday night, a shallow ridge pushes in from the west, bringing dry conditions to the forecast area with troughs to the north over northern British Columbia and south over the Great Basin.
On Friday, increased clouds will accompany a broad trough approaching from coastal British Columbia, which will reach our area by late afternoon. Precipitation will spread into our area.
Friday night, the precipitation will increase as the trough deepens and NW flow increases aloft.
On Saturday, the trough shifts east and weak ridging decreases the precipitation by afternoon.
Extended Weather
Olympics, Washington Cascades and Mt. Hood Area
Extended Snow/Freezing Levels
| Mt. Baker | Snoqualmie Pass | Mt. Hood | Easterly Flow * | ||
|---|---|---|---|---|---|
| Thursday | Snow Level | 0' - 0' | 0' - 1000' | 0' - 0' | |
| Thursday Night | Snow Level | 0' - 0' | 0' - 0' | 0' - 0' | |
| Friday | Snow Level | 0' - 0' | 0' - 1000' | 0' - 1000' | |
| Friday Night | Snow Level | 0' - 1000' | 0' - 1000' | 0' - 1000' | |
| Saturday | Snow Level | 0' - 1000' | 0' - 1000' | 1000' - 2000' |
| Mt. Baker | Elevation |
|---|---|
| Thursday |
Snow Level 0' - 0' |
| Thursday Night |
Snow Level 0' - 0' |
| Friday |
Snow Level 0' - 0' |
| Friday Night |
Snow Level 0' - 1000' |
| Saturday |
Snow Level 0' - 1000' |
| Snoqualmie Pass | Elevation |
|---|---|
| Thursday |
Snow Level 0' - 1000' |
| Thursday Night |
Snow Level 0' - 0' |
| Friday |
Snow Level 0' - 1000' |
| Friday Night |
Snow Level 0' - 1000' |
| Saturday |
Snow Level 0' - 1000' |
| Mt. Hood | Elevation |
|---|---|
| Thursday |
Snow Level 0' - 0' |
| Thursday Night |
Snow Level 0' - 0' |
| Friday |
Snow Level 0' - 1000' |
| Friday Night |
Snow Level 0' - 1000' |
| Saturday |
Snow Level 1000' - 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.
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 20, 2018
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