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 & Monday
A shortwave ridge moving over the PNW will provide us with some fine weather on Christmas Day. Freezing levels will be low but at least skies will be mostly clear with light winds.
The fair weather will not last long as a strong westerly jet once again becomes squarely aimed at Washington Monday night. High clouds should increase overnight and through Monday morning as moisture begins to stream into the region.
Cloud ceilings should lower quickly Monday afternoon with light rain and snow spreading south from the Olympics and north Cascades. Alpine winds will also ramp up quickly Monday afternoon, so expect reduced visibility late in the day if above treeline.
The bulk of precipitation from the incoming frontal system will move in Monday night. A slight warming trend should take place overnight out ahead of and with the frontal passage for the Olympics and west slopes of the Cascades with snow levels peaking near 3000 feet after midnight through the early morning hours of Tuesday for the central Cascades including Snoqualmie Pass and 3500 feet for the south Washington Cascades including Crystal, Paradise and White Pass.
Forecast models from this morning seem a notch cooler and faster with the precipitation for Monday night but not enough for drastic changes in the forecast.
Weather Forecast
Olympics
| Sunday |
Mostly sunny. |
| Sunday Night |
Mostly clear becoming mostly cloudy overnight with increasing high clouds. |
| Monday |
Light rain and snow. Becoming windy in the afternoon. |
| Monday Night |
Stormy. Slight warming trend Monday night. |
Washington Cascades near and west of the crest including Stevens, Snoqualmie, and White Passes
| Sunday Afternoon |
Mostly sunny. |
| Sunday Night - Monday Morning |
Mostly clear becoming mostly cloudy late Sunday night with increasing high clouds. Light snow developing north Cascades Monday morning. |
| Monday Afternoon |
Clouds lowering with alpine winds increasing. Light snow. |
| Monday Night |
Becoming stormy. Slight warming trend late Monday night. |
East slopes of the Washington Cascades
| Sunday Afternoon |
Mostly sunny. |
| Sunday Night - Monday Morning |
Mostly clear becoming mostly cloudy late Sunday night with increasing high clouds. Very light snow developing northeast Cascades Monday morning. |
| Monday Afternoon |
Clouds lowering with alpine winds increasing. Light snow northeast Cascades spreading south in the afternoon. |
| Monday Night |
Light to moderate snow, heaviest near the Cascade crest. Strong alpine winds. |
Mt. Hood Area
| Sunday |
Mostly sunny. |
| Sunday Night - Monday Morning |
Mostly clear becoming partly cloudy late Sunday night with increasing high clouds. |
| Monday Afternoon |
Becoming mostly cloudy with alpine winds increasing. |
| Monday Night |
Light to moderate rain and snow becoming stormy after midnight. Slight warming trend late Monday night. |
Issued: 1:53 PM PST Sunday, December 25, 2016
Snow/Freezing Level (ft)
| Hurricane Ridge | Mt. Baker | Washington Pass | Leavenworth | Stevens Pass | Snoqualmie Pass | Mt. Rainier, Crystal & White Pass | Mt. Hood | ||
|---|---|---|---|---|---|---|---|---|---|
| Sunday - Sunday Night | Freezing Level | 1000' | 500' | 500' | ' | ' | 500' | ' | 1000' |
| Monday Morning | Snow Level * | 2000' | 500' | 500' | ' | ' | 1000' | ' | 1500' |
| Monday Afternoon - Monday Evening | Snow Level * | 3000' | 1500' | 500' | ' | ' | 1500' | ' | 2000' |
| Monday Night | Snow Level * | 3500' | 2500' | 1500' | ' | ' | 3000' | ' | 400' |
| Hurricane Ridge | Elevation |
|---|---|
| Sunday - Sunday Night |
Freezing Level 1000' |
| Monday Morning |
Snow Level 2000' (Easterly Flow *) |
| Monday Afternoon - Monday Evening |
Snow Level 3000' (Easterly Flow *) |
| Monday Night |
Snow Level 3500' (Easterly Flow *) |
| Mt. Baker | Elevation |
|---|---|
| Sunday - Sunday Night |
Freezing Level 500' |
| Monday Morning |
Snow Level 500' (Easterly Flow *) |
| Monday Afternoon - Monday Evening |
Snow Level 1500' (Easterly Flow *) |
| Monday Night |
Snow Level 2500' (Easterly Flow *) |
| Washington Pass | Elevation |
|---|---|
| Sunday - Sunday Night |
Freezing Level 500' |
| Monday Morning |
Snow Level 500' (Easterly Flow *) |
| Monday Afternoon - Monday Evening |
Snow Level 500' (Easterly Flow *) |
| Monday Night |
Snow Level 1500' (Easterly Flow *) |
| Leavenworth | Elevation |
|---|---|
| Sunday - Sunday Night |
Freezing Level ' |
| Monday Morning |
Snow Level ' (Easterly Flow *) |
| Monday Afternoon - Monday Evening |
Snow Level ' (Easterly Flow *) |
| Monday Night |
Snow Level ' (Easterly Flow *) |
| Stevens Pass | Elevation |
|---|---|
| Sunday - Sunday Night |
Freezing Level ' |
| Monday Morning |
Snow Level ' (Easterly Flow *) |
| Monday Afternoon - Monday Evening |
Snow Level ' (Easterly Flow *) |
| Monday Night |
Snow Level ' (Easterly Flow *) |
| Snoqualmie Pass | Elevation |
|---|---|
| Sunday - Sunday Night |
Freezing Level 500' |
| Monday Morning |
Snow Level 1000' (Easterly Flow *) |
| Monday Afternoon - Monday Evening |
Snow Level 1500' (Easterly Flow *) |
| Monday Night |
Snow Level 3000' (Easterly Flow *) |
| Mt. Rainier & Crystal | Elevation |
|---|---|
| Sunday - Sunday Night |
Freezing Level ' |
| Monday Morning |
Snow Level ' (Easterly Flow *) |
| Monday Afternoon - Monday Evening |
Snow Level ' (Easterly Flow *) |
| Monday Night |
Snow Level ' (Easterly Flow *) |
| Mt. Hood | Elevation |
|---|---|
| Sunday - Sunday Night |
Freezing Level 1000' |
| Monday Morning |
Snow Level 1500' (Easterly Flow *) |
| Monday Afternoon - Monday Evening |
Snow Level 2000' (Easterly Flow *) |
| Monday Night |
Snow Level 400' (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
| Monday | Monday | |
|---|---|---|
| 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 | 0.50 - 0.75 |
| Stevens Pass | LT 0.10 | 0 - 1.00 |
| Snoqualmie Pass | LT 0.10 | 1.00 - 1.50 |
| Mission Ridge | LT 0.10 | 0.25 - 0.50 |
| Crystal Mt | LT 0.10 | 0 - 0.75 |
| Paradise | LT 0.10 | 0 - 1.50 |
| White Pass | LT 0.10 | 0.75 - 1.00 |
| Mt Hood Meadows | LT 0.10 | 0 - 1.00 |
| Timberline | LT 0.10 | 1.00 - 1.50 |
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: 1:53 PM PST Sunday, December 25, 2016
Free Winds at 5000' (mph)
| Hurricane Ridge | Mt. Baker | Stevens to Snoqualmie Pass | Mt. Rainier | Mt. Hood | |
|---|---|---|---|---|---|
| Sunday | VAR 0 - 10 | VAR 0 - 10 | VAR 0 - 10 | --- - | W 0 - 10 |
| Sunday Night - Monday Morning | SW 0 - 10 | SW 0 - 10 | SW 0 - 10 | --- - | SW 0 - 10 |
| Monday Afternoon | SW 20 - 30 | S 15 - 25 | S 15 - 25 | --- - | SW 10 - 20 |
| Monday Night | SW 20 - 30 | SW 20 - 30 | WSW 20 - 35 | --- - | WSW 35 - 45 |
| Hurricane Ridge | Elevation |
|---|---|
| Sunday | VAR 0 - 10 |
| Sunday Night - Monday Morning | SW 0 - 10 |
| Monday Afternoon | SW 20 - 30 |
| Monday Night | SW 20 - 30 |
| Mt. Baker | Elevation |
|---|---|
| Sunday | VAR 0 - 10 |
| Sunday Night - Monday Morning | SW 0 - 10 |
| Monday Afternoon | S 15 - 25 |
| Monday Night | SW 20 - 30 |
| Stevens and Snoqualmie Pass | Elevation |
|---|---|
| Sunday | VAR 0 - 10 |
| Sunday Night - Monday Morning | SW 0 - 10 |
| Monday Afternoon | S 15 - 25 |
| Monday Night | WSW 20 - 35 |
| Mt. Rainier | Elevation |
|---|---|
| Sunday | --- - |
| Sunday Night - Monday Morning | --- - |
| Monday Afternoon | --- - |
| Monday Night | --- - |
| Mt. Hood | Elevation |
|---|---|
| Sunday | W 0 - 10 |
| Sunday Night - Monday Morning | SW 0 - 10 |
| Monday Afternoon | SW 10 - 20 |
| Monday Night | WSW 35 - 45 |
| Hurricane Ridge | Direction - Speed |
|---|---|
| Sunday | VAR 0 - 10 |
| Sunday Night - Monday Morning | SW 0 - 10 |
| Monday Afternoon | SW 20 - 30 |
| Monday Night | SW 20 - 30 |
| Mt. Baker | Direction - Speed |
|---|---|
| Sunday | VAR 0 - 10 |
| Sunday Night - Monday Morning | SW 0 - 10 |
| Monday Afternoon | S 15 - 25 |
| Monday Night | SW 20 - 30 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Sunday | VAR 0 - 10 |
| Sunday Night - Monday Morning | SW 0 - 10 |
| Monday Afternoon | S 15 - 25 |
| Monday Night | WSW 20 - 35 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Sunday | --- - |
| Sunday Night - Monday Morning | --- - |
| Monday Afternoon | --- - |
| Monday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| Sunday | W 0 - 10 |
| Sunday Night - Monday Morning | SW 0 - 10 |
| Monday Afternoon | SW 10 - 20 |
| Monday Night | WSW 35 - 45 |
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 | NW 0 - 10 | NW 0 - 10 | NW 0 - 10 | --- - | NW 0 - 10 |
| Sunday Night - Monday Morning | WNW 10 - 20 | WNW 10 - 20 | WNW 10 - 20 | --- - | WNW 10 - 20 |
| Monday Afternoon | SW 30 - 40 | SW 30 - 40 | SW 30 - 45 | --- - | WSW 25 - 35 |
| Monday Night | SW 35 - 50 | SW 40 - 50 | WSW 50 - 60 | --- - | WSW 60 - 70 |
| Mt. Baker | Direction - Speed |
|---|---|
| Sunday | NW 0 - 10 |
| Sunday Night - Monday Morning | WNW 10 - 20 |
| Monday Afternoon | SW 30 - 40 |
| Monday Night | SW 35 - 50 |
| Washington Pass | Direction - Speed |
|---|---|
| Sunday | NW 0 - 10 |
| Sunday Night - Monday Morning | WNW 10 - 20 |
| Monday Afternoon | SW 30 - 40 |
| Monday Night | SW 40 - 50 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Sunday | NW 0 - 10 |
| Sunday Night - Monday Morning | WNW 10 - 20 |
| Monday Afternoon | SW 30 - 45 |
| Monday Night | WSW 50 - 60 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Sunday | --- - |
| Sunday Night - Monday Morning | --- - |
| Monday Afternoon | --- - |
| Monday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| Sunday | NW 0 - 10 |
| Sunday Night - Monday Morning | WNW 10 - 20 |
| Monday Afternoon | WSW 25 - 35 |
| Monday Night | WSW 60 - 70 |
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: 1:53 PM PST Sunday, December 25, 2016
Extended Weather Synopsis for Monday night through Monday
The stormy snow pattern that began on Monday night will continue through Tuesday night with strong westerly flow enhancing orographic showers along the west slopes of the Olympics and Cascades including Mt. Hood. After snow levels peak early Tuesday morning, snow levels will quickly settle down into the 2000-2500 ft range by late morning and slightly cool further during the day.
A trailing trough may invigorate shower activity late Tuesday afternoon through the evening. Shower intensity should decrease and become more scattered in nature Tuesday night, with more moderate accumulations possible if a convergence zone forms.
Westerly winds will stay strong throughout this event, especially hammering the Mt. Hood area.
An upper level ridge will temporarily build along the West Coast on Wednesday, pushing the jet stream north and bringing precipitation to an end. There should be some partial clearing for the south Washington Cascades and Mt. Hood on Wednesday.
A warm front should brush the north Cascades and Olympics Wednesday night with light rain and snow. As the associated surface low curls NE into the central B.C. coast Wednesday night, the cold front will sag south spreading light to moderate precipitation to the central Washington Cascades while Mt. Hood stays dry. A warming trend on Wednesday night and Thursday should be initially muted by strong easterly flow developing in the Cascades Passes.
Extended Weather
Olympics, Washington Cascades and Mt. Hood area
Moderate to occasionally heavy rain and snow showers west slopes of the Olympics and Cascades and Mt. Hood. Light to occasionally moderate rain and snow showers east slopes of the Cascades. Windy. Cooling trend.
Mostly cloudy with scattered light snow showers, occasionally moderate west slopes of the Cascades.
Mostly cloudy north Cascades and Olympics. Partly cloudy south Washington Cascades and Mt. Hood.
Cloudy. Light rain and snow developing Olympics and north Cascades.
Light to occasionally moderate rain and snow Olympics and Cascades. Mostly cloudy Mt. Hood. Slight warming trend.
Extended Snow/Freezing Levels
| Mt. Baker | Snoqualmie Pass | Mt. Hood | Easterly Flow * | ||
|---|---|---|---|---|---|
| Tuesday Morning | Snow Level | 2000' - 3000' | 2000' - 3000' | 3000' - 4000' | |
| Tuesday Afternoon | Snow Level | 1500' - 2500' | 1500' - 2500' | 2000' - 3000' | |
| Tuesday Night - Wednesday | Snow Level | 1000' - 2000' | 500' - 1500' | 1500' - 2500' | |
| Wednesday Night | Snow Level | 1000' - 2000' | 1000' - 2000' | 3000' - 4000' | * |
| Thursday | Snow Level | 2500' - 3000' | 3000' - 4000' | 4500' - 5500' | * |
| Mt. Baker | Elevation |
|---|---|
| Tuesday Morning |
Snow Level 2000' - 3000' |
| Tuesday Afternoon |
Snow Level 1500' - 2500' |
| Tuesday Night - Wednesday |
Snow Level 1000' - 2000' |
| Wednesday Night |
Snow Level 1000' - 2000' (Easterly Flow *) |
| Thursday |
Snow Level 2500' - 3000' (Easterly Flow *) |
| Snoqualmie Pass | Elevation |
|---|---|
| Tuesday Morning |
Snow Level 2000' - 3000' |
| Tuesday Afternoon |
Snow Level 1500' - 2500' |
| Tuesday Night - Wednesday |
Snow Level 500' - 1500' |
| Wednesday Night |
Snow Level 1000' - 2000' (Easterly Flow *) |
| Thursday |
Snow Level 3000' - 4000' (Easterly Flow *) |
| Mt. Hood | Elevation |
|---|---|
| Tuesday Morning |
Snow Level 3000' - 4000' |
| Tuesday Afternoon |
Snow Level 2000' - 3000' |
| Tuesday Night - Wednesday |
Snow Level 1500' - 2500' |
| Wednesday Night |
Snow Level 3000' - 4000' (Easterly Flow *) |
| Thursday |
Snow Level 4500' - 5500' (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 25, 2016
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