Jump to: Weather Forecast I Snow/Freezing Level I Precipitation I Free Winds 5k I Free Winds 9k I Extended Weather
Weather Synopsis for Sunday & Friday
A frontal system sagging south through the Washington Cascades Saturday night delivered some nice snow totals for the Olympics, the west slopes of the Cascades and Mt. Hood. Through 4 am Sunday morning, new snow totals generally ranged from 8 - 20 inches for the aforementioned areas. The post-frontal convergence zone continues to become more northwest oriented and should continue to weaken through the afternoon hours. As showers decrease, sunbreaks should become more common this afternoon.
A strong 125 kt jet that was directed into Washington State this morning will drop south and into central Oregon by Sunday afternoon. The PNW will be on the backside of a cold upper trough; the coldest air mass by far this season will be over the region beginning Sunday evening. A weak front should swing down the backside of the trough on Monday. Generally light accumulations of snow are possible Monday with showers becoming more scattered in the afternoon and evening. While shower activity will generally be dying down Monday night, there may be some light to moderate upslope snowfall along the north slopes of the Olympics with a bit of Fraser outflow developing late Monday afternoon.
Weather Forecast
Olympics
| Sunday |
Partly sunny with isolated light snow showers. Colder. |
| Sunday Night - Monday Morning |
Becoming cloudy with light snow increasing after midnight. |
| Monday Morning - Monday Mid-day |
Mostly cloudy with scattered light snow showers. |
| Monday Afternoon - Monday Night |
Mostly cloudy with light to moderate snow showers north slopes of the Olympics. |
Washington Cascades near and west of the crest including Stevens, Snoqualmie, and White Passes
| Sunday Mid-day |
Mostly cloudy with isolated snow showers north Cascades. Cloudy with light snow showers central and south Washington Cascades. Moderate westerly ridgetop winds. |
| Sunday Afternoon - Sunday Night |
Becoming partly cloudy Sunday afternoon from north to south with isolated light snow showers. Colder. |
| Monday Morning |
Cloudy with light snow showers. |
| Monday Afternoon - Monday Night |
Mostly cloudy with scattered light snow showers tapering off Monday night. |
East slopes of the Washington Cascades
| Sunday Afternoon - Sunday Night |
Mostly cloudy near the crest, partly sunny further east. Turning colder. |
| Monday Morning |
Cloudy with light snow showers developing. |
| Monday Afternoon - Monday Night |
Parlty to mostly cloudy with scattered light snow showers tapering off Monday night. |
Mt. Hood Area
| Sunday Afternoon - Sunday Night |
Mostly cloudy with scattered light snow showers. Moderate alpine westerly winds. Colder. |
| Monday Morning |
Cloudy with light snow showers. |
| Monday Afternoon - Monday Night |
Mostly cloudy with scattered light snow showers tapering off Monday night. |
Issued: 1:35 PM PST Sunday, December 4, 2016
Snow/Freezing Level (ft)
| Hurricane Ridge | Mt. Baker | Washington Pass | Leavenworth | Stevens Pass | Snoqualmie Pass | Mt. Rainier, Crystal & White Pass | Mt. Hood | ||
|---|---|---|---|---|---|---|---|---|---|
| Sunday Afternoon | Snow Level | 1000' | 500' | 500' | ' | ' | 1000' | ' | 2000' |
| Sunday Night - Monday Night | Snow Level | 1000' | 500' | 0' | ' | ' | 500' | ' | 1000' |
| Hurricane Ridge | Elevation |
|---|---|
| Sunday Afternoon |
Snow Level 1000' |
| Sunday Night - Monday Night |
Snow Level 1000' |
| Mt. Baker | Elevation |
|---|---|
| Sunday Afternoon |
Snow Level 500' |
| Sunday Night - Monday Night |
Snow Level 500' |
| Washington Pass | Elevation |
|---|---|
| Sunday Afternoon |
Snow Level 500' |
| Sunday Night - Monday Night |
Snow Level 0' |
| Leavenworth | Elevation |
|---|---|
| Sunday Afternoon |
Snow Level ' |
| Sunday Night - Monday Night |
Snow Level ' |
| Stevens Pass | Elevation |
|---|---|
| Sunday Afternoon |
Snow Level ' |
| Sunday Night - Monday Night |
Snow Level ' |
| Snoqualmie Pass | Elevation |
|---|---|
| Sunday Afternoon |
Snow Level 1000' |
| Sunday Night - Monday Night |
Snow Level 500' |
| Mt. Rainier & Crystal | Elevation |
|---|---|
| Sunday Afternoon |
Snow Level ' |
| Sunday Night - Monday Night |
Snow Level ' |
| Mt. Hood | Elevation |
|---|---|
| Sunday Afternoon |
Snow Level 2000' |
| Sunday Night - Monday Night |
Snow Level 1000' |
* 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 0.25 | 0.50 - 0.75 |
| Mt Baker Ski Area | LT 0.25 | LT 0.25 |
| Washington Pass | LT 0.10 | LT 0.25 |
| Stevens Pass | 0 - 0.50 | LT 0.25 |
| Snoqualmie Pass | 0.50 - 0.75 | LT 0.25 |
| Mission Ridge | LT 0.10 | LT 0.25 |
| Crystal Mt | 0 - 0.50 | LT 0.25 |
| Paradise | 0 - 0.50 | 0 - 0.50 |
| White Pass | 0.25 - 0.50 | 0.25 - 0.50 |
| Mt Hood Meadows | 0 - 1.00 | 0 - 0.75 |
| Timberline | 1.00 - 1.50 | 0 - 1.00 |
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: 1:35 PM PST Sunday, December 4, 2016
Free Winds at 5000' (mph)
| Hurricane Ridge | Mt. Baker | Stevens to Snoqualmie Pass | Mt. Rainier | Mt. Hood | |
|---|---|---|---|---|---|
| Sunday Afternoon - Sunday Evening | NW 10 - 20 | WNW 0 - 10 | NW 10 - 20 | --- - | NW 15 - 25 |
| Sunday Night - Monday Morning | SW 5 - 15 | S 0 - 10 | SW 5 - 15 | --- - | W 10 - 20 |
| Monday - Monday Night | N 0 - 10 | ENE 5 - 15 | VAR 0 - 10 | --- - | W 5 - 15 |
| Hurricane Ridge | Elevation |
|---|---|
| Sunday Afternoon - Sunday Evening | NW 10 - 20 |
| Sunday Night - Monday Morning | SW 5 - 15 |
| Monday - Monday Night | N 0 - 10 |
| Mt. Baker | Elevation |
|---|---|
| Sunday Afternoon - Sunday Evening | WNW 0 - 10 |
| Sunday Night - Monday Morning | S 0 - 10 |
| Monday - Monday Night | ENE 5 - 15 |
| Stevens and Snoqualmie Pass | Elevation |
|---|---|
| Sunday Afternoon - Sunday Evening | NW 10 - 20 |
| Sunday Night - Monday Morning | SW 5 - 15 |
| Monday - Monday Night | VAR 0 - 10 |
| Mt. Rainier | Elevation |
|---|---|
| Sunday Afternoon - Sunday Evening | --- - |
| Sunday Night - Monday Morning | --- - |
| Monday - Monday Night | --- - |
| Mt. Hood | Elevation |
|---|---|
| Sunday Afternoon - Sunday Evening | NW 15 - 25 |
| Sunday Night - Monday Morning | W 10 - 20 |
| Monday - Monday Night | W 5 - 15 |
| Hurricane Ridge | Direction - Speed |
|---|---|
| Sunday Afternoon - Sunday Evening | NW 10 - 20 |
| Sunday Night - Monday Morning | SW 5 - 15 |
| Monday - Monday Night | N 0 - 10 |
| Mt. Baker | Direction - Speed |
|---|---|
| Sunday Afternoon - Sunday Evening | WNW 0 - 10 |
| Sunday Night - Monday Morning | S 0 - 10 |
| Monday - Monday Night | ENE 5 - 15 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Sunday Afternoon - Sunday Evening | NW 10 - 20 |
| Sunday Night - Monday Morning | SW 5 - 15 |
| Monday - Monday Night | VAR 0 - 10 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Sunday Afternoon - Sunday Evening | --- - |
| Sunday Night - Monday Morning | --- - |
| Monday - Monday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| Sunday Afternoon - Sunday Evening | NW 15 - 25 |
| Sunday Night - Monday Morning | W 10 - 20 |
| Monday - Monday Night | W 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 | |
|---|---|---|---|---|---|
| Sunday Afternoon - Sunday Evening | NW 15 - 25 | NW 10 - 20 | NW 35 - 45 | --- - | NW 30 - 40 |
| Sunday Night - Monday Morning | SW 5 - 15 | W 10 - 20 | W 15 - 25 | --- - | W 20 - 30 |
| Monday Afternoon | E 0 - 10 | E 0 - 10 | W 5 - 15 | --- - | W 15 - 30 |
| Monday Night | NE 5 - 15 | NE 0 - 10 | NE 0 - 10 | --- - | NW 5 - 15 |
| Mt. Baker | Direction - Speed |
|---|---|
| Sunday Afternoon - Sunday Evening | NW 15 - 25 |
| Sunday Night - Monday Morning | SW 5 - 15 |
| Monday Afternoon | E 0 - 10 |
| Monday Night | NE 5 - 15 |
| Washington Pass | Direction - Speed |
|---|---|
| Sunday Afternoon - Sunday Evening | NW 10 - 20 |
| Sunday Night - Monday Morning | W 10 - 20 |
| Monday Afternoon | E 0 - 10 |
| Monday Night | NE 0 - 10 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Sunday Afternoon - Sunday Evening | NW 35 - 45 |
| Sunday Night - Monday Morning | W 15 - 25 |
| Monday Afternoon | W 5 - 15 |
| Monday Night | NE 0 - 10 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Sunday Afternoon - Sunday Evening | --- - |
| Sunday Night - Monday Morning | --- - |
| Monday Afternoon | --- - |
| Monday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| Sunday Afternoon - Sunday Evening | NW 30 - 40 |
| Sunday Night - Monday Morning | W 20 - 30 |
| Monday Afternoon | W 15 - 30 |
| Monday Night | NW 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.
Issued: 1:35 PM PST Sunday, December 4, 2016
Extended Weather Synopsis for Friday night through Friday
Tuesday should be fair weather day with cold temperatures settled into the region. An upper level ridge offshore will move over the west coast on Wednesday providing one more break day between weather systems. Strong high pressure in the Yukon and northern B.C. will slide south along the Rockies during this time, setting the stage for moderate offshore flow to develop Wednesday and Thursday. A strong frontal system looks to impact the area beginning Wednesday night and especially Thursday. With cold air firmly entrenched along the east slopes, warming should be limited to the Olympics and perhaps Mt. Hood on Thursday.
Extended Weather
Olympics, Washington Cascades and Mt. Hood
Partly to mostly clear and cold.
Mostly sunny except increasing clouds Olympics Wednesday afternoon. Moderate to strong offshore flow developing.
Light to moderate snow developing overnight. Moderate to strong offshore flow.
Stormy. Some warming Olympics and Mt. Hood.
Extended Snow/Freezing Levels
| Mt. Baker | Snoqualmie Pass | Mt. Hood | Easterly Flow * | ||
|---|---|---|---|---|---|
| Tuesday - Wednesday Night | Freezing Level | 0' - 500' | 0' - 500' | 0' - 500' | * |
| Thursday | Snow Level | 0' - 1000' | 0' - 1000' | 3000' - 4000' | * |
| Mt. Baker | Elevation |
|---|---|
| Tuesday - Wednesday Night |
Freezing Level 0' - 500' (Easterly Flow *) |
| Thursday |
Snow Level 0' - 1000' (Easterly Flow *) |
| Snoqualmie Pass | Elevation |
|---|---|
| Tuesday - Wednesday Night |
Freezing Level 0' - 500' (Easterly Flow *) |
| Thursday |
Snow Level 0' - 1000' (Easterly Flow *) |
| Mt. Hood | Elevation |
|---|---|
| Tuesday - Wednesday Night |
Freezing Level 0' - 500' (Easterly Flow *) |
| Thursday |
Snow Level 3000' - 4000' (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.
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 4, 2016
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