Jump to: Weather Forecast I Snow/Freezing Level I Precipitation I Free Winds 5k I Free Winds 9k I Extended Weather
Weather Synopsis for Wednesday & Wednesday
The snow tap will remain open over the west slopes of the Cascades and Mt. Hood today. A stacked area of low pressure off the northern coast of Vancouver Island combined with cool W-NW flow aloft will continue the steady stream of showers over the PNW. Snow levels will remain cold and orographic westerly flow will help enhance shower activity mainly over the central and southern Washington Cascades and Mt. Hood with lighter amounts over the north Cascades and east slopes. The air mass over the PNW will be unstable and a few embedded thunderstorms are possible today as well.
The low pressure system will weaken overnight and the upper level trough will broaden and open, leading to decreasing shower intensity overnight, except at Mt. Hood where moderate showers will linger through Thursday AM.
Scattered showers on Thursday should produce only light additional accumulations as an upper ridge begins to build offshore with the highest accumulations over the west slopes. Showers will further decrease Thursday night.
Weather Forecast
Olympics, Washington Cascades near and west of the crest including Stevens, Snoqualmie, and White Passes
| Wednesday - Wednesday Evening |
Light to moderate snow showers, occasionally heavy over the south Washington Cascades including Mt.Rainier. |
| Wednesday Night - Thursday |
Mostly cloudy with scattered light to occasionally moderate snow showers. |
| Thursday Night |
Mostly cloudy with isolated light snow showers. |
Mt. Hood Area
| Wednesday - Thursday Morning |
Moderate snow showers. |
| Thursday Afternoon |
Mostly cloudy with scattered light to occasionally moderate snow showers. |
| Thursday Night |
Mostly cloudy with isolated light snow showers. |
East slopes of the Washington Cascades
| Wednesday - Wednesday Evening |
Light snow showers, except moderate near the Cascade crest in the south and central east Cascades. |
| Wednesday Night - Thursday |
Mostly cloudy with scattered light snow showers. |
| Thursday Night |
Partly cloudy with isolated light snow showers. |
Issued: 7:16 AM PST Wednesday, December 23, 2015
Snow/Freezing Level (ft)
| Hurricane Ridge | Mt. Baker | Washington Pass | Leavenworth | Stevens Pass | Snoqualmie Pass | Mt. Rainier, Crystal & White Pass | Mt. Hood | ||
|---|---|---|---|---|---|---|---|---|---|
| Wednesday Morning | Snow Level | 2000' | 1000' | 0' | ' | ' | 1000' | ' | 1500' |
| Wednesday Afternoon | Snow Level | 2000' | 1500' | 1000' | ' | ' | 2000' | ' | 2000' |
| Wednesday Night - Thursday | Snow Level * | 2000' | 1000' | 1000' | ' | ' | 1000' | ' | 1500' |
| Thursday Night | Snow Level | 1000' | 0' | 0' | ' | ' | 500' | ' | 1000' |
| Hurricane Ridge | Elevation |
|---|---|
| Wednesday Morning |
Snow Level 2000' |
| Wednesday Afternoon |
Snow Level 2000' |
| Wednesday Night - Thursday |
Snow Level 2000' (Easterly Flow *) |
| Thursday Night |
Snow Level 1000' |
| Mt. Baker | Elevation |
|---|---|
| Wednesday Morning |
Snow Level 1000' |
| Wednesday Afternoon |
Snow Level 1500' |
| Wednesday Night - Thursday |
Snow Level 1000' (Easterly Flow *) |
| Thursday Night |
Snow Level 0' |
| Washington Pass | Elevation |
|---|---|
| Wednesday Morning |
Snow Level 0' |
| Wednesday Afternoon |
Snow Level 1000' |
| Wednesday Night - Thursday |
Snow Level 1000' (Easterly Flow *) |
| Thursday Night |
Snow Level 0' |
| Leavenworth | Elevation |
|---|---|
| Wednesday Morning |
Snow Level ' |
| Wednesday Afternoon |
Snow Level ' |
| Wednesday Night - Thursday |
Snow Level ' (Easterly Flow *) |
| Thursday Night |
Snow Level ' |
| Stevens Pass | Elevation |
|---|---|
| Wednesday Morning |
Snow Level ' |
| Wednesday Afternoon |
Snow Level ' |
| Wednesday Night - Thursday |
Snow Level ' (Easterly Flow *) |
| Thursday Night |
Snow Level ' |
| Snoqualmie Pass | Elevation |
|---|---|
| Wednesday Morning |
Snow Level 1000' |
| Wednesday Afternoon |
Snow Level 2000' |
| Wednesday Night - Thursday |
Snow Level 1000' (Easterly Flow *) |
| Thursday Night |
Snow Level 500' |
| Mt. Rainier & Crystal | Elevation |
|---|---|
| Wednesday Morning |
Snow Level ' |
| Wednesday Afternoon |
Snow Level ' |
| Wednesday Night - Thursday |
Snow Level ' (Easterly Flow *) |
| Thursday Night |
Snow Level ' |
| Mt. Hood | Elevation |
|---|---|
| Wednesday Morning |
Snow Level 1500' |
| Wednesday Afternoon |
Snow Level 2000' |
| Wednesday Night - Thursday |
Snow Level 1500' (Easterly Flow *) |
| Thursday 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
| Wednesday | Wednesday | |
|---|---|---|
| Hurricane Ridge | 0.75 - 1.00 | LT 0.10 |
| Mt Baker Ski Area | 0 - 0.50 | LT 0.25 |
| Washington Pass | 0.25 - 0.50 | LT 0.25 |
| Stevens Pass | 0 - 1.00 | LT 0.25 |
| Snoqualmie Pass | 0 - 1.50 | LT 0.25 |
| Mission Ridge | LT 0.25 | LT 0.10 |
| Crystal Mt | 1.00 - 1.50 | LT 0.25 |
| Paradise | 1.50 - 2.50 | 0 - 0.50 |
| White Pass | 1.50 - 2.00 | 0.25 - 0.50 |
| Mt Hood Meadows | 0 - 1.50 | 0 - 0.75 |
| Timberline | 0 - 2.00 | 0.75 - 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: 7:16 AM PST Wednesday, December 23, 2015
Free Winds at 5000' (mph)
| Hurricane Ridge | Mt. Baker | Stevens to Snoqualmie Pass | Mt. Rainier | Mt. Hood | |
|---|---|---|---|---|---|
| Wednesday Morning | WNW 15 - 25 | VAR 0 - 10 | W 15 - 25 | --- - | W 25 - 35 |
| Wednesday Afternoon | WSW 15 - 25 | VAR 0 - 10 | WSW 15 - 25 | --- - | W 25 - 35 |
| Wednesday Night | W 10 - 20 | S 0 - 10 | SW 10 - 20 | --- - | WSW 15 - 25 |
| Thursday - Thursday Night | WNW 5 - 15 | SW 0 - 10 | SW 5 - 15 | --- - | WSW 10 - 20 |
| Hurricane Ridge | Elevation |
|---|---|
| Wednesday Morning | WNW 15 - 25 |
| Wednesday Afternoon | WSW 15 - 25 |
| Wednesday Night | W 10 - 20 |
| Thursday - Thursday Night | WNW 5 - 15 |
| Mt. Baker | Elevation |
|---|---|
| Wednesday Morning | VAR 0 - 10 |
| Wednesday Afternoon | VAR 0 - 10 |
| Wednesday Night | S 0 - 10 |
| Thursday - Thursday Night | SW 0 - 10 |
| Stevens and Snoqualmie Pass | Elevation |
|---|---|
| Wednesday Morning | W 15 - 25 |
| Wednesday Afternoon | WSW 15 - 25 |
| Wednesday Night | SW 10 - 20 |
| Thursday - Thursday Night | SW 5 - 15 |
| Mt. Rainier | Elevation |
|---|---|
| Wednesday Morning | --- - |
| Wednesday Afternoon | --- - |
| Wednesday Night | --- - |
| Thursday - Thursday Night | --- - |
| Mt. Hood | Elevation |
|---|---|
| Wednesday Morning | W 25 - 35 |
| Wednesday Afternoon | W 25 - 35 |
| Wednesday Night | WSW 15 - 25 |
| Thursday - Thursday Night | WSW 10 - 20 |
| Hurricane Ridge | Direction - Speed |
|---|---|
| Wednesday Morning | WNW 15 - 25 |
| Wednesday Afternoon | WSW 15 - 25 |
| Wednesday Night | W 10 - 20 |
| Thursday - Thursday Night | WNW 5 - 15 |
| Mt. Baker | Direction - Speed |
|---|---|
| Wednesday Morning | VAR 0 - 10 |
| Wednesday Afternoon | VAR 0 - 10 |
| Wednesday Night | S 0 - 10 |
| Thursday - Thursday Night | SW 0 - 10 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Wednesday Morning | W 15 - 25 |
| Wednesday Afternoon | WSW 15 - 25 |
| Wednesday Night | SW 10 - 20 |
| Thursday - Thursday Night | SW 5 - 15 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Wednesday Morning | --- - |
| Wednesday Afternoon | --- - |
| Wednesday Night | --- - |
| Thursday - Thursday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| Wednesday Morning | W 25 - 35 |
| Wednesday Afternoon | W 25 - 35 |
| Wednesday Night | WSW 15 - 25 |
| Thursday - Thursday Night | WSW 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 | |
|---|---|---|---|---|---|
| Wednesday Morning | W 5 - 15 | W 5 - 15 | NW 30 - 40 | --- - | NW 40 - 50 |
| Wednesday Afternoon | SW 15 - 25 | WSW 20 - 30 | W 30 - 40 | --- - | W 35 - 45 |
| Wednesday Night | SW 10 - 20 | SW 15 - 25 | WSW 30 - 40 | --- - | W 25 - 35 |
| Thursday | SW 5 - 15 | W 0 - 10 | W 15 - 30 | --- - | WNW 20 - 30 |
| Thursday Night | WNW 5 - 15 | WNW 10 - 20 | NW 10 - 20 | --- - | NW 15 - 25 |
| Mt. Baker | Direction - Speed |
|---|---|
| Wednesday Morning | W 5 - 15 |
| Wednesday Afternoon | SW 15 - 25 |
| Wednesday Night | SW 10 - 20 |
| Thursday | SW 5 - 15 |
| Thursday Night | WNW 5 - 15 |
| Washington Pass | Direction - Speed |
|---|---|
| Wednesday Morning | W 5 - 15 |
| Wednesday Afternoon | WSW 20 - 30 |
| Wednesday Night | SW 15 - 25 |
| Thursday | W 0 - 10 |
| Thursday Night | WNW 10 - 20 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Wednesday Morning | NW 30 - 40 |
| Wednesday Afternoon | W 30 - 40 |
| Wednesday Night | WSW 30 - 40 |
| Thursday | W 15 - 30 |
| Thursday Night | NW 10 - 20 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Wednesday Morning | --- - |
| Wednesday Afternoon | --- - |
| Wednesday Night | --- - |
| Thursday | --- - |
| Thursday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| Wednesday Morning | NW 40 - 50 |
| Wednesday Afternoon | W 35 - 45 |
| Wednesday Night | W 25 - 35 |
| Thursday | WNW 20 - 30 |
| Thursday Night | NW 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: 7:16 AM PST Wednesday, December 23, 2015
Extended Weather Synopsis for Wednesday night through Wednesday
The ridge axis should be located offshore around 135 W on Christmas Day with only isolated and light showers over the mountains. Snow levels will remain low. A dry period for later Friday through Sunday morning looks likely as the upper level ridge passes inland. High clouds from an approaching frontal system may cover the northern half of the Washington Cascades by Saturday afternoon. Models disagree whether or not a splitting frontal system will push inland on Sunday... but in any scenario this system looks relatively weak compared to our recent snowy pattern. Looking ahead, the weather pattern appears much less active through the end of 2015.
Extended Weather
Olympics, Washington Cascades and Mt. Hood area
Partly cloudy with isolated mountain snow showers. Continued low snow/freezing levels.
Mostly clear
Mostly cloudy north part, mostly clear south part.
Light rain and snow developing Olympics. Cloudy elsewhere.
Extended Snow/Freezing Levels
| Mt. Baker | Snoqualmie Pass | Mt. Hood | Easterly Flow * | ||
|---|---|---|---|---|---|
| Friday - Saturday Morning | Freezing Level | 0' - 1000' | 0' - 1000' | 500' - 1500' | |
| Saturday Afternoon - Sunday Morning | Freezing Level | 1500' - 2500' | 1500' - 2500' | 2000' - 4000' | * |
| Sunday Afternoon | Snow Level | 1000' - 2000' | 1000' - 2000' | 1500' - 2500' | * |
| Mt. Baker | Elevation |
|---|---|
| Friday - Saturday Morning |
Freezing Level 0' - 1000' |
| Saturday Afternoon - Sunday Morning |
Freezing Level 1500' - 2500' (Easterly Flow *) |
| Sunday Afternoon |
Snow Level 1000' - 2000' (Easterly Flow *) |
| Snoqualmie Pass | Elevation |
|---|---|
| Friday - Saturday Morning |
Freezing Level 0' - 1000' |
| Saturday Afternoon - Sunday Morning |
Freezing Level 1500' - 2500' (Easterly Flow *) |
| Sunday Afternoon |
Snow Level 1000' - 2000' (Easterly Flow *) |
| Mt. Hood | Elevation |
|---|---|
| Friday - Saturday Morning |
Freezing Level 500' - 1500' |
| Saturday Afternoon - Sunday Morning |
Freezing Level 2000' - 4000' (Easterly Flow *) |
| Sunday Afternoon |
Snow Level 1500' - 2500' (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 16, 2015
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