Jump to: Weather Forecast I Snow/Freezing Level I Precipitation I Free Winds 5k I Free Winds 9k I Extended Weather
Weather Synopsis for Friday & Wednesday
A longwave upper trough is digging off the California coast while dry northerly flow is seen aloft and at the surface over the PNW. The sensible weather effects can best be summarized as it's cold out there and the winds are relatively light outside of a stiff NE breeze at Mt. Baker, Hurricane Ridge and Mission Ridge. Low-mid clouds have been stubborn to break up for a few spots outside of the north Cascades and Olympics but plenty of areas are enjoying sunshine on an otherwise cold December day.
A weak upper level shortwave approaching in NW flow aloft will pass through the Washington Cascades Saturday. This will increase high clouds Friday night and moisture up to about crest level on Saturday. Expect mostly cloudy conditions along the west slopes with sunbreaks mostly likely to poke out for the Mt. Baker area and the Olympics as well as decreasing cloud cover further east of the Cascade crest. A few light snow showers are likely on Saturday along the west slopes as well.
Warm frontal moisture also coming down in NW flow aloft will begin to nick the Olympics and north Cascades with light precipitation early Sunday morning. Temperatures will remain cold through the short term with snow/freezing levels near sea level.
Weather Forecast
Olympics
| Friday Afternoon |
Mostly sunny and cold. |
| Friday Night |
Mostly clear, then becoming mostly cloudy overnight with increasing mid and high clouds. |
| Saturday |
Mostly cloudy with occasional light snow showers mainly in the morning, becoming partly sunny Saturday afternoon. |
| Saturday Night |
Increasing clouds with light rain and snow developing late Saturday night. |
Washington Cascades near and west of the crest including Stevens, Snoqualmie, and White Passes
| Friday Afternoon |
Mostly sunny north Cascades. Partly sunny south and central Cascades and Passes. Cold. |
| Friday Night |
Partly cloudy, then becoming mostly cloudy overnight with increasing mid and high clouds. |
| Saturday - Saturday Night |
Mostly cloudy with occasional light snow showers especially central and south Cascades. |
East slopes of the Washington Cascades
| Friday Afternoon |
Partly to mostly sunny. Areas of clouds lower slopes and Passes mainly in the south and central east Cascades. |
| Friday Night |
Mostly clear, then becoming partly to mostly cloudy overnight with increasing mid and high clouds. |
| Saturday - Saturday Night |
Mostly cloudy with occasional light snow showers near the Cascade crest but decreasing clouds and partly cloudy further east. |
Mt. Hood Area
| Friday Afternoon |
Mix of sun and clouds. Cold. |
| Friday Night |
Mostly clear, then becoming mostly cloudy overnight with increasing mid and high clouds. |
| Saturday - Saturday Night |
Mostly cloudy with a chance of very light snow showers. |
Issued: 1:59 PM PST Friday, December 16, 2016
Snow/Freezing Level (ft)
| Hurricane Ridge | Mt. Baker | Washington Pass | Leavenworth | Stevens Pass | Snoqualmie Pass | Mt. Rainier, Crystal & White Pass | Mt. Hood | ||
|---|---|---|---|---|---|---|---|---|---|
| Friday - Friday Night | Freezing Level | 0' | 0' | 0' | ' | ' | 0' | ' | 0' |
| Saturday - Saturday Night | Snow Level | 500' | 0' | 0' | ' | ' | 0' | ' | 500' |
| Hurricane Ridge | Elevation |
|---|---|
| Friday - Friday Night |
Freezing Level 0' |
| Saturday - Saturday Night |
Snow Level 500' |
| Mt. Baker | Elevation |
|---|---|
| Friday - Friday Night |
Freezing Level 0' |
| Saturday - Saturday Night |
Snow Level 0' |
| Washington Pass | Elevation |
|---|---|
| Friday - Friday Night |
Freezing Level 0' |
| Saturday - Saturday Night |
Snow Level 0' |
| Leavenworth | Elevation |
|---|---|
| Friday - Friday Night |
Freezing Level ' |
| Saturday - Saturday Night |
Snow Level ' |
| Stevens Pass | Elevation |
|---|---|
| Friday - Friday Night |
Freezing Level ' |
| Saturday - Saturday Night |
Snow Level ' |
| Snoqualmie Pass | Elevation |
|---|---|
| Friday - Friday Night |
Freezing Level 0' |
| Saturday - Saturday Night |
Snow Level 0' |
| Mt. Rainier & Crystal | Elevation |
|---|---|
| Friday - Friday Night |
Freezing Level ' |
| Saturday - Saturday Night |
Snow Level ' |
| Mt. Hood | Elevation |
|---|---|
| Friday - Friday Night |
Freezing Level 0' |
| Saturday - Saturday Night |
Snow Level 500' |
* 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
| Wednesday | Wednesday | |
|---|---|---|
| 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 0.25 |
| 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 |
| 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: 1:59 PM PST Friday, December 16, 2016
Free Winds at 5000' (mph)
| Hurricane Ridge | Mt. Baker | Stevens to Snoqualmie Pass | Mt. Rainier | Mt. Hood | |
|---|---|---|---|---|---|
| Friday Afternoon | NE 5 - 15 | NE 5 - 15 | VAR 0 - 10 | --- - | VAR 0 - 10 |
| Friday Night - Saturday Morning | W 5 - 15 | W 0 - 10 | W 0 - 10 | --- - | W 5 - 15 |
| Saturday Afternoon - Saturday Night | NW 10 - 20 | VAR 0 - 10 | WNW 5 - 15 | --- - | WNW 10 - 20 |
| Hurricane Ridge | Elevation |
|---|---|
| Friday Afternoon | NE 5 - 15 |
| Friday Night - Saturday Morning | W 5 - 15 |
| Saturday Afternoon - Saturday Night | NW 10 - 20 |
| Mt. Baker | Elevation |
|---|---|
| Friday Afternoon | NE 5 - 15 |
| Friday Night - Saturday Morning | W 0 - 10 |
| Saturday Afternoon - Saturday Night | VAR 0 - 10 |
| Stevens and Snoqualmie Pass | Elevation |
|---|---|
| Friday Afternoon | VAR 0 - 10 |
| Friday Night - Saturday Morning | W 0 - 10 |
| Saturday Afternoon - Saturday Night | WNW 5 - 15 |
| Mt. Rainier | Elevation |
|---|---|
| Friday Afternoon | --- - |
| Friday Night - Saturday Morning | --- - |
| Saturday Afternoon - Saturday Night | --- - |
| Mt. Hood | Elevation |
|---|---|
| Friday Afternoon | VAR 0 - 10 |
| Friday Night - Saturday Morning | W 5 - 15 |
| Saturday Afternoon - Saturday Night | WNW 10 - 20 |
| Hurricane Ridge | Direction - Speed |
|---|---|
| Friday Afternoon | NE 5 - 15 |
| Friday Night - Saturday Morning | W 5 - 15 |
| Saturday Afternoon - Saturday Night | NW 10 - 20 |
| Mt. Baker | Direction - Speed |
|---|---|
| Friday Afternoon | NE 5 - 15 |
| Friday Night - Saturday Morning | W 0 - 10 |
| Saturday Afternoon - Saturday Night | VAR 0 - 10 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Friday Afternoon | VAR 0 - 10 |
| Friday Night - Saturday Morning | W 0 - 10 |
| Saturday Afternoon - Saturday Night | WNW 5 - 15 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Friday Afternoon | --- - |
| Friday Night - Saturday Morning | --- - |
| Saturday Afternoon - Saturday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| Friday Afternoon | VAR 0 - 10 |
| Friday Night - Saturday Morning | W 5 - 15 |
| Saturday Afternoon - Saturday Night | WNW 10 - 20 |
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 | |
|---|---|---|---|---|---|
| Friday Afternoon | N 10 - 20 | N 15 - 30 | N 15 - 25 | --- - | N 15 - 25 |
| Friday Night | NW 15 - 25 | NW 10 - 20 | NW 15 - 30 | --- - | NW 15 - 30 |
| Saturday - Saturday Night | NW 15 - 25 | NNW 15 - 25 | NW 20 - 35 | --- - | NW 20 - 30 |
| Mt. Baker | Direction - Speed |
|---|---|
| Friday Afternoon | N 10 - 20 |
| Friday Night | NW 15 - 25 |
| Saturday - Saturday Night | NW 15 - 25 |
| Washington Pass | Direction - Speed |
|---|---|
| Friday Afternoon | N 15 - 30 |
| Friday Night | NW 10 - 20 |
| Saturday - Saturday Night | NNW 15 - 25 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Friday Afternoon | N 15 - 25 |
| Friday Night | NW 15 - 30 |
| Saturday - Saturday Night | NW 20 - 35 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Friday Afternoon | --- - |
| Friday Night | --- - |
| Saturday - Saturday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| Friday Afternoon | N 15 - 25 |
| Friday Night | NW 15 - 30 |
| Saturday - Saturday 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.
Issued: 1:59 PM PST Friday, December 16, 2016
Extended Weather Synopsis for Wednesday night through Wednesday
Warm frontal moisture will continue to drape over the north Cascades and Olympics and slowly spread south Sunday and Sunday night. Snow levels should slowly moderate on Sunday. Most of the moisture will stay north of Mt. Hood until the cold front sweeps through mid-day Monday. Post-frontal shower activity looks brief Monday afternoon, but should feature a period of strong winds with and following the frontal passage.
The jet stream should drop south and become aimed at Washington and Oregon on Monday night, aiding a stronger low pressure system's development during this time frame. This strong low pressure system will impact the area with heavier precipitation, stronger winds, and more fluctuation in snow levels through most of Tuesday.
Extended Weather
Olympics, Washington Cascades and Mt. Hood
Cloudy with steady light rain and snow north Cascades and Olympics. Cloudy with periods of light rain and snow south and central Washington Cascades. Cloudy Mt. Hood. Slow warming trend.
Light to moderate rain and snow spreading south Sunday night and becoming light showers mid-day Monday. Windy. Milder.
Stormy with a warming trend Monday night. Rain and snow becoming showers Tuesday afternoon.
Extended Snow/Freezing Levels
| Mt. Baker | Snoqualmie Pass | Mt. Hood | Easterly Flow * | ||
|---|---|---|---|---|---|
| Sunday | Snow Level | 1000' - 2000' | 1500' - 2500' | 2000' - 3000' | |
| Sunday Night - Monday Morning | Snow Level | 2000' - 3000' | 2000' - 3000' | 3000' - 4000' | * |
| Monday Afternoon | Snow Level | 2500' - 3500' | 3000' - 4000' | 4000' - 5000' | |
| Monday Night - Tuesday Morning | Snow Level | 2000' - 3500' | 3000' - 5000' | 6000' - 7000' | * |
| Tuesday Afternoon | Snow Level | 2500' - 3500' | 2500' - 3500' | 2500' - 3500' |
| Mt. Baker | Elevation |
|---|---|
| Sunday |
Snow Level 1000' - 2000' |
| Sunday Night - Monday Morning |
Snow Level 2000' - 3000' (Easterly Flow *) |
| Monday Afternoon |
Snow Level 2500' - 3500' |
| Monday Night - Tuesday Morning |
Snow Level 2000' - 3500' (Easterly Flow *) |
| Tuesday Afternoon |
Snow Level 2500' - 3500' |
| Snoqualmie Pass | Elevation |
|---|---|
| Sunday |
Snow Level 1500' - 2500' |
| Sunday Night - Monday Morning |
Snow Level 2000' - 3000' (Easterly Flow *) |
| Monday Afternoon |
Snow Level 3000' - 4000' |
| Monday Night - Tuesday Morning |
Snow Level 3000' - 5000' (Easterly Flow *) |
| Tuesday Afternoon |
Snow Level 2500' - 3500' |
| Mt. Hood | Elevation |
|---|---|
| Sunday |
Snow Level 2000' - 3000' |
| Sunday Night - Monday Morning |
Snow Level 3000' - 4000' (Easterly Flow *) |
| Monday Afternoon |
Snow Level 4000' - 5000' |
| Monday Night - Tuesday Morning |
Snow Level 6000' - 7000' (Easterly Flow *) |
| Tuesday Afternoon |
Snow Level 2500' - 3500' |
* 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 Dec 16, 2016
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