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 & Saturday
Afternoon update: Precipitation and winds have been slightly raised for Day 2.
A stacked low pressure system is slowly migrating southeastward along the north Oregon coast and should pass into central Oregon late today.
This weather system will largely miss the Washington Cascades, producing only occasional light snow for Mt. Rainier and areas south. Mt. Hood will be the main snow benefactor from this system, with light to moderate precipitation developing in the afternoon.
Surface ridging will briefly build over the PNW later Friday night through early Saturday morning as the next system begins to develop in westerly flow. Precipitation will start over the Olympics later Saturday morning and spread inland during the day, with winds and precipitiation intensity ramping up over the Cascades by Saturday afternoon.
A brief and subtle warm up should occur from the central Cascades down to Mt. Hood Saturday afternoon and early evening, and later in the evening for the Cascade Passes once there is a switch to westerly flow.
Weather Forecast
Olympics
| Friday Afternoon - Friday Evening |
Becoming partly cloudy in the afternoon. |
| Friday Night |
Increasing high and mid level clouds overnight. |
| Saturday |
Light rain and snow developing in the morning and becoming moderate in the afternoon. Slight warming trend into the afternoon. |
| Saturday Night |
Moderate rain and snow becoming light to moderate showers early Saturday evening. |
Washington Cascades near and west of the crest including Stevens, Snoqualmie, and White Passes
| Friday Afternoon - Friday Evening |
Partly cloudy north Cascades, cloudy with occasional light snow south Washington Cascades. |
| Friday Night - Saturday Morning |
Partly cloudy, becoming mostly cloudy Saturday morning with increasing high and mid level clouds. |
| Saturday Mid-day - Saturday Afternoon |
Light rain and snow developing by late morning and becoming light to moderate in the afternoon, especially south Washington Cascades. |
| Saturday Night |
Moderate rain and snow becoming light to moderate showers Saturday evening. Slight warming trend into the evening, mainly central and south Washington Cascades. |
East slopes of the Washington Cascades
| Friday Afternoon - Friday Evening |
Mostly cloudy northeast Cascades, cloudy with occasional light snow southeast Washington Cascades. |
| Friday Night - Saturday Morning |
Partly cloudy, becoming mostly cloudy Saturday morning with increasing high and mid level clouds. |
| Saturday Mid-day - Saturday Afternoon |
Light snow developing mid-day, becoming moderate rain and snow near the Cascade crest in the afternoon. |
| Saturday Night |
Light to moderate snow becoming light to moderate showers Saturday evening. Slight warming trend in the evening. |
Mt. Hood Area
| Friday Afternoon - Friday Evening |
Light to moderate rain and snow. |
| Friday Night - Saturday Morning |
Light rain and snow showers. |
| Saturday Mid-day - Saturday Night |
Light to moderate rain and snow, except occasionally heavy in the late afternoon and evening. Slight warming trend in the afternoon and evening. |
Issued: 2:38 PM PST Friday, December 11, 2015
Snow/Freezing Level (ft)
| Hurricane Ridge | Mt. Baker | Washington Pass | Leavenworth | Stevens Pass | Snoqualmie Pass | Mt. Rainier, Crystal & White Pass | Mt. Hood | ||
|---|---|---|---|---|---|---|---|---|---|
| Friday | Snow Level * | 3500' | 3000' | 3000' | ' | ' | 3500' | ' | 3000' |
| Friday Night - Saturday Morning | Snow Level * | 2000' | 1500' | 1000' | ' | ' | 2000' | ' | 2500' |
| Saturday Afternoon | Snow Level * | 4500' | 2500' | 2500' | ' | ' | 3000' | ' | 4000' |
| Saturday Evening | Snow Level | 3500' | 3000' | 2500' | ' | ' | 3000' | ' | 4500' |
| Saturday Night | Snow Level | 3000' | 3000' | 3000' | ' | ' | 3000' | ' | 4000' |
| Hurricane Ridge | Elevation |
|---|---|
| Friday |
Snow Level 3500' (Easterly Flow *) |
| Friday Night - Saturday Morning |
Snow Level 2000' (Easterly Flow *) |
| Saturday Afternoon |
Snow Level 4500' (Easterly Flow *) |
| Saturday Evening |
Snow Level 3500' |
| Saturday Night |
Snow Level 3000' |
| Mt. Baker | Elevation |
|---|---|
| Friday |
Snow Level 3000' (Easterly Flow *) |
| Friday Night - Saturday Morning |
Snow Level 1500' (Easterly Flow *) |
| Saturday Afternoon |
Snow Level 2500' (Easterly Flow *) |
| Saturday Evening |
Snow Level 3000' |
| Saturday Night |
Snow Level 3000' |
| Washington Pass | Elevation |
|---|---|
| Friday |
Snow Level 3000' (Easterly Flow *) |
| Friday Night - Saturday Morning |
Snow Level 1000' (Easterly Flow *) |
| Saturday Afternoon |
Snow Level 2500' (Easterly Flow *) |
| Saturday Evening |
Snow Level 2500' |
| Saturday Night |
Snow Level 3000' |
| Leavenworth | Elevation |
|---|---|
| Friday |
Snow Level ' (Easterly Flow *) |
| Friday Night - Saturday Morning |
Snow Level ' (Easterly Flow *) |
| Saturday Afternoon |
Snow Level ' (Easterly Flow *) |
| Saturday Evening |
Snow Level ' |
| Saturday Night |
Snow Level ' |
| Stevens Pass | Elevation |
|---|---|
| Friday |
Snow Level ' (Easterly Flow *) |
| Friday Night - Saturday Morning |
Snow Level ' (Easterly Flow *) |
| Saturday Afternoon |
Snow Level ' (Easterly Flow *) |
| Saturday Evening |
Snow Level ' |
| Saturday Night |
Snow Level ' |
| Snoqualmie Pass | Elevation |
|---|---|
| Friday |
Snow Level 3500' (Easterly Flow *) |
| Friday Night - Saturday Morning |
Snow Level 2000' (Easterly Flow *) |
| Saturday Afternoon |
Snow Level 3000' (Easterly Flow *) |
| Saturday Evening |
Snow Level 3000' |
| Saturday Night |
Snow Level 3000' |
| Mt. Rainier & Crystal | Elevation |
|---|---|
| Friday |
Snow Level ' (Easterly Flow *) |
| Friday Night - Saturday Morning |
Snow Level ' (Easterly Flow *) |
| Saturday Afternoon |
Snow Level ' (Easterly Flow *) |
| Saturday Evening |
Snow Level ' |
| Saturday Night |
Snow Level ' |
| Mt. Hood | Elevation |
|---|---|
| Friday |
Snow Level 3000' (Easterly Flow *) |
| Friday Night - Saturday Morning |
Snow Level 2500' (Easterly Flow *) |
| Saturday Afternoon |
Snow Level 4000' (Easterly Flow *) |
| Saturday Evening |
Snow Level 4500' |
| Saturday Night |
Snow Level 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.
Precipitation Forecast
| Saturday | Saturday | |
|---|---|---|
| Hurricane Ridge | LT 0.10 | 0.50 - 0.75 |
| Mt Baker Ski Area | LT 0.10 | 1.00 - 1.50 |
| Washington Pass | LT 0.10 | 0 - 0.75 |
| Stevens Pass | LT 0.10 | 0.75 - 1.00 |
| Snoqualmie Pass | LT 0.10 | 1.00 - 1.50 |
| Mission Ridge | LT 0.10 | 0 - 0.50 |
| Crystal Mt | LT 0.10 | 0.75 - 1.00 |
| Paradise | LT 0.25 | 0 - 1.50 |
| White Pass | LT 0.25 | 0 - 1.00 |
| Mt Hood Meadows | 0 - 1.00 | 1.50 - 2.00 |
| Timberline | 1.00 - 1.50 | 2.00 - 2.50 |
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: 2:38 PM PST Friday, December 11, 2015
Free Winds at 5000' (mph)
| Hurricane Ridge | Mt. Baker | Stevens to Snoqualmie Pass | Mt. Rainier | Mt. Hood | |
|---|---|---|---|---|---|
| Friday Afternoon | VAR 0 - 10 | VAR 0 - 10 | E 0 - 10 | --- - | E 10 - 20 |
| Friday Night | W 0 - 10 | VAR 0 - 10 | VAR 0 - 10 | --- - | VAR 0 - 10 |
| Saturday Morning | S 15 - 25 | SSE 10 - 20 | SE 10 - 20 | --- - | SW 10 - 20 |
| Saturday Afternoon | SW 25 - 35 | SE 15 - 25 | SE 20 - 30 | --- - | SW 20 - 30 |
| Saturday Night | SW 20 - 30 | SW 15 - 25 | SW 15 - 25 | --- - | WSW 20 - 30 |
| Hurricane Ridge | Elevation |
|---|---|
| Friday Afternoon | VAR 0 - 10 |
| Friday Night | W 0 - 10 |
| Saturday Morning | S 15 - 25 |
| Saturday Afternoon | SW 25 - 35 |
| Saturday Night | SW 20 - 30 |
| Mt. Baker | Elevation |
|---|---|
| Friday Afternoon | VAR 0 - 10 |
| Friday Night | VAR 0 - 10 |
| Saturday Morning | SSE 10 - 20 |
| Saturday Afternoon | SE 15 - 25 |
| Saturday Night | SW 15 - 25 |
| Stevens and Snoqualmie Pass | Elevation |
|---|---|
| Friday Afternoon | E 0 - 10 |
| Friday Night | VAR 0 - 10 |
| Saturday Morning | SE 10 - 20 |
| Saturday Afternoon | SE 20 - 30 |
| Saturday Night | SW 15 - 25 |
| Mt. Rainier | Elevation |
|---|---|
| Friday Afternoon | --- - |
| Friday Night | --- - |
| Saturday Morning | --- - |
| Saturday Afternoon | --- - |
| Saturday Night | --- - |
| Mt. Hood | Elevation |
|---|---|
| Friday Afternoon | E 10 - 20 |
| Friday Night | VAR 0 - 10 |
| Saturday Morning | SW 10 - 20 |
| Saturday Afternoon | SW 20 - 30 |
| Saturday Night | WSW 20 - 30 |
| Hurricane Ridge | Direction - Speed |
|---|---|
| Friday Afternoon | VAR 0 - 10 |
| Friday Night | W 0 - 10 |
| Saturday Morning | S 15 - 25 |
| Saturday Afternoon | SW 25 - 35 |
| Saturday Night | SW 20 - 30 |
| Mt. Baker | Direction - Speed |
|---|---|
| Friday Afternoon | VAR 0 - 10 |
| Friday Night | VAR 0 - 10 |
| Saturday Morning | SSE 10 - 20 |
| Saturday Afternoon | SE 15 - 25 |
| Saturday Night | SW 15 - 25 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Friday Afternoon | E 0 - 10 |
| Friday Night | VAR 0 - 10 |
| Saturday Morning | SE 10 - 20 |
| Saturday Afternoon | SE 20 - 30 |
| Saturday Night | SW 15 - 25 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Friday Afternoon | --- - |
| Friday Night | --- - |
| Saturday Morning | --- - |
| Saturday Afternoon | --- - |
| Saturday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| Friday Afternoon | E 10 - 20 |
| Friday Night | VAR 0 - 10 |
| Saturday Morning | SW 10 - 20 |
| Saturday Afternoon | SW 20 - 30 |
| Saturday Night | WSW 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 | |
|---|---|---|---|---|---|
| Friday Afternoon | VAR 0 - 10 | VAR 0 - 10 | SE 0 - 10 | --- - | W 5 - 15 |
| Friday Night | WSW 5 - 15 | W 0 - 10 | WNW 5 - 15 | --- - | NW 10 - 20 |
| Saturday Morning | S 15 - 25 | SSW 10 - 20 | SW 15 - 25 | --- - | SW 15 - 25 |
| Saturday Afternoon | SW 50 - 60 | S 30 - 40 | SW 60 - 70 | --- - | SW 60 - 70 |
| Saturday Night | S 30 - 40 | SW 25 - 35 | WNW 25 - 35 | --- - | SW 30 - 40 |
| Mt. Baker | Direction - Speed |
|---|---|
| Friday Afternoon | VAR 0 - 10 |
| Friday Night | WSW 5 - 15 |
| Saturday Morning | S 15 - 25 |
| Saturday Afternoon | SW 50 - 60 |
| Saturday Night | S 30 - 40 |
| Washington Pass | Direction - Speed |
|---|---|
| Friday Afternoon | VAR 0 - 10 |
| Friday Night | W 0 - 10 |
| Saturday Morning | SSW 10 - 20 |
| Saturday Afternoon | S 30 - 40 |
| Saturday Night | SW 25 - 35 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Friday Afternoon | SE 0 - 10 |
| Friday Night | WNW 5 - 15 |
| Saturday Morning | SW 15 - 25 |
| Saturday Afternoon | SW 60 - 70 |
| Saturday Night | WNW 25 - 35 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Friday Afternoon | --- - |
| Friday Night | --- - |
| Saturday Morning | --- - |
| Saturday Afternoon | --- - |
| Saturday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| Friday Afternoon | W 5 - 15 |
| Friday Night | NW 10 - 20 |
| Saturday Morning | SW 15 - 25 |
| Saturday Afternoon | SW 60 - 70 |
| Saturday Night | SW 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.
Issued: 2:38 PM PST Friday, December 11, 2015
Extended Weather Synopsis for Saturday night through Saturday
Another wave will develop along the frontal boundary draped over Oregon and CA with steady precipitaiton continuing down in the Mt. Hood area late Saturday night through Sunday morning. Post frontal showers will be the story over Washington Sunday. Colder air will settle over the region later Sunday into early next week. Upper ridging will build offshore Sunday night and help dry out the area on Monday. A weak upper level disturbance may pass through in NW flow aloft Tuesday afternoon producing generally light precipitation for northern areas.
Extended Weather
Olympics, Washington Cascades and Mt. Hood area
Light to occasionally moderate rain and snow showers. Heaviest showers Mt. Hood area.
Scattered light snow showers tapering down Sunday night and Monday with partial clearing Monday. Colder.
Becoming mostly cloudy north part with occasional light snow in the afternoon. Partly cloudy south part.
Extended Snow/Freezing Levels
| Mt. Baker | Snoqualmie Pass | Mt. Hood | Easterly Flow * | ||
|---|---|---|---|---|---|
| Sunday | Snow Level | 2500' - 3500' | 2500' - 3500' | 2500' - 4000' | |
| Sunday Night - Monday Night | Snow Level | 2000' - 3000' | 2000' - 3000' | 2000' - 3000' | |
| Tuesday | Snow Level | 1500' - 2500' | 1500' - 2500' | 2000' - 3000' |
| Mt. Baker | Elevation |
|---|---|
| Sunday |
Snow Level 2500' - 3500' |
| Sunday Night - Monday Night |
Snow Level 2000' - 3000' |
| Tuesday |
Snow Level 1500' - 2500' |
| Snoqualmie Pass | Elevation |
|---|---|
| Sunday |
Snow Level 2500' - 3500' |
| Sunday Night - Monday Night |
Snow Level 2000' - 3000' |
| Tuesday |
Snow Level 1500' - 2500' |
| Mt. Hood | Elevation |
|---|---|
| Sunday |
Snow Level 2500' - 4000' |
| Sunday Night - Monday Night |
Snow Level 2000' - 3000' |
| Tuesday |
Snow Level 2000' - 3000' |
* 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 11, 2015
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