Jump to: Weather Forecast I Snow/Freezing Level I Precipitation I Free Winds 5k I Free Winds 9k I Extended Weather
Weather Synopsis for Thursday & Sunday
Merry Christmas and Happy Holidays from the Northwest Avalanche Center!
Scattered showers should continue today for the mountains with some light snow accumulations expected. A convergence zone downwind of Vancouver Island will continue to focus a steady stream of light snow showers in the Stevens Pass vicinity. Expect winds near crest level to be moderate out of the NW... and even strong down near Mt. Hood.
A developing system in the Gulf of Alaska will begin to flatten the upper level ridge positioned offshore. The system will approach from the NW Friday night... with increasing clouds and light precipitation spreading over the north and central Cascades and Olympics by early Saturday morning.
Weather Forecast
Olympics, Washington Cascades near and west of the crest including Stevens, Snoqualmie, and White Passes
| Thursday |
Partly to mostly cloudy. Scattered snow showers. |
| Thursday Night - Friday Morning |
Partly cloudy with isolated snow showers. |
| Friday Afternoon - Friday Evening |
Increasing mid and high level clouds. Isolated snow showers. |
| Friday Night |
Light to moderate rain and snow developing late overnight. Winds increasing. |
East slopes of the Washington Cascades
| Thursday |
Partly cloudy. Isolated snow showers. |
| Thursday Night - Friday Morning |
Mostly clear. |
| Friday Afternoon - Friday Evening |
Partly cloudy, then increasing mid and high level clouds. |
| Friday Night |
Light rain and snow developing late overnight. Winds increasing. |
Mt. Hood Area
| Thursday |
Partly to mostly cloudy. Scattered snow showers. Strong upper mountain winds. |
| Thursday Night - Friday |
Partly cloudy with isolated snow showers. |
| Friday Night |
Increasing mid and high level clouds early. Light rain and snow developing late overnight. Winds increasing. |
Issued: 8:27 AM PST Thursday, December 25, 2014
Snow/Freezing Level (ft)
| Hurricane Ridge | Mt. Baker | Washington Pass | Leavenworth | Stevens Pass | Snoqualmie Pass | Mt. Rainier, Crystal & White Pass | Mt. Hood | ||
|---|---|---|---|---|---|---|---|---|---|
| Thursday - Thursday Night | Snow Level | 2500' | 2000' | 1500' | ' | ' | 2000' | ' | 2500' |
| Friday - Friday Night | Snow Level | 3500' | 2500' | 2000' | ' | ' | 3000' | ' | 3500' |
| Hurricane Ridge | Elevation |
|---|---|
| Thursday - Thursday Night |
Snow Level 2500' |
| Friday - Friday Night |
Snow Level 3500' |
| Mt. Baker | Elevation |
|---|---|
| Thursday - Thursday Night |
Snow Level 2000' |
| Friday - Friday Night |
Snow Level 2500' |
| Washington Pass | Elevation |
|---|---|
| Thursday - Thursday Night |
Snow Level 1500' |
| Friday - Friday Night |
Snow Level 2000' |
| Leavenworth | Elevation |
|---|---|
| Thursday - Thursday Night |
Snow Level ' |
| Friday - Friday Night |
Snow Level ' |
| Stevens Pass | Elevation |
|---|---|
| Thursday - Thursday Night |
Snow Level ' |
| Friday - Friday Night |
Snow Level ' |
| Snoqualmie Pass | Elevation |
|---|---|
| Thursday - Thursday Night |
Snow Level 2000' |
| Friday - Friday Night |
Snow Level 3000' |
| Mt. Rainier & Crystal | Elevation |
|---|---|
| Thursday - Thursday Night |
Snow Level ' |
| Friday - Friday Night |
Snow Level ' |
| Mt. Hood | Elevation |
|---|---|
| Thursday - Thursday Night |
Snow Level 2500' |
| Friday - Friday Night |
Snow Level 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.
Precipitation Forecast
| Sunday | Sunday | |
|---|---|---|
| Hurricane Ridge | LT 0.10 | LT 0.25 |
| Mt Baker Ski Area | LT 0.10 | LT 0.25 |
| Washington Pass | LT 0.10 | LT 0.10 |
| Stevens Pass | LT 0.25 | LT 0.25 |
| Snoqualmie Pass | LT 0.25 | LT 0.25 |
| Mission Ridge | LT 0.10 | LT 0.10 |
| Crystal Mt | LT 0.10 | LT 0.10 |
| Paradise | LT 0.10 | LT 0.10 |
| 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: 8:27 AM PST Thursday, December 25, 2014
Free Winds at 5000' (mph)
| Hurricane Ridge | Mt. Baker | Stevens to Snoqualmie Pass | Mt. Rainier | Mt. Hood | |
|---|---|---|---|---|---|
| Thursday - Thursday Night | NW 5 - 15 | W 5 - 15 | NW 5 - 15 | --- - | NW 10 - 20 |
| Friday - Friday Evening | W 5 - 15 | SW 0 - 10 | W 0 - 10 | --- - | W 5 - 15 |
| Friday Night | W 15 - 25 | SW 15 - 25 | W 10 - 20 | --- - | W 10 - 20 |
| Hurricane Ridge | Elevation |
|---|---|
| Thursday - Thursday Night | NW 5 - 15 |
| Friday - Friday Evening | W 5 - 15 |
| Friday Night | W 15 - 25 |
| Mt. Baker | Elevation |
|---|---|
| Thursday - Thursday Night | W 5 - 15 |
| Friday - Friday Evening | SW 0 - 10 |
| Friday Night | SW 15 - 25 |
| Stevens and Snoqualmie Pass | Elevation |
|---|---|
| Thursday - Thursday Night | NW 5 - 15 |
| Friday - Friday Evening | W 0 - 10 |
| Friday Night | W 10 - 20 |
| Mt. Rainier | Elevation |
|---|---|
| Thursday - Thursday Night | --- - |
| Friday - Friday Evening | --- - |
| Friday Night | --- - |
| Mt. Hood | Elevation |
|---|---|
| Thursday - Thursday Night | NW 10 - 20 |
| Friday - Friday Evening | W 5 - 15 |
| Friday Night | W 10 - 20 |
| Hurricane Ridge | Direction - Speed |
|---|---|
| Thursday - Thursday Night | NW 5 - 15 |
| Friday - Friday Evening | W 5 - 15 |
| Friday Night | W 15 - 25 |
| Mt. Baker | Direction - Speed |
|---|---|
| Thursday - Thursday Night | W 5 - 15 |
| Friday - Friday Evening | SW 0 - 10 |
| Friday Night | SW 15 - 25 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Thursday - Thursday Night | NW 5 - 15 |
| Friday - Friday Evening | W 0 - 10 |
| Friday Night | W 10 - 20 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Thursday - Thursday Night | --- - |
| Friday - Friday Evening | --- - |
| Friday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| Thursday - Thursday Night | NW 10 - 20 |
| Friday - Friday Evening | W 5 - 15 |
| Friday Night | W 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 | |
|---|---|---|---|---|---|
| Thursday | NW 10 - 20 | NW 5 - 15 | NW 20 - 30 | --- - | NW 35 - 50 |
| Thursday Night | NW 10 - 20 | NW 5 - 15 | NW 15 - 25 | --- - | NW 25 - 35 |
| Friday - Friday Evening | NW 15 - 25 | W 5 - 15 | NW 20 - 30 | --- - | NW 15 - 25 |
| Friday Night | W 20 - 30 | WNW 25 - 35 | NW 40 - 50 | --- - | NW 30 - 40 |
| Mt. Baker | Direction - Speed |
|---|---|
| Thursday | NW 10 - 20 |
| Thursday Night | NW 10 - 20 |
| Friday - Friday Evening | NW 15 - 25 |
| Friday Night | W 20 - 30 |
| Washington Pass | Direction - Speed |
|---|---|
| Thursday | NW 5 - 15 |
| Thursday Night | NW 5 - 15 |
| Friday - Friday Evening | W 5 - 15 |
| Friday Night | WNW 25 - 35 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Thursday | NW 20 - 30 |
| Thursday Night | NW 15 - 25 |
| Friday - Friday Evening | NW 20 - 30 |
| Friday Night | NW 40 - 50 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Thursday | --- - |
| Thursday Night | --- - |
| Friday - Friday Evening | --- - |
| Friday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| Thursday | NW 35 - 50 |
| Thursday Night | NW 25 - 35 |
| Friday - Friday Evening | NW 15 - 25 |
| Friday Night | NW 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: 8:27 AM PST Thursday, December 25, 2014
Extended Weather Synopsis for Sunday night through Sunday
The closed upper low will pass over the central-north Cascades Saturday and quickly traverse toward the ID/WA border Saturday night. This upper low should deliver a healthy shot of snow to PNW mountains Saturday and Saturday night in favorable W-NW flow. Snow levels should stay on the cool side... but a mid-day bump to near or above 3000 feet for Snoqualmie Pass area is still possible.
Strong arctic high pressure will begin to slide south out of northern British Columbia Sunday. The upper level flow should quickly turn northerly on Sunday... with some clearing and decreasing showers during the day. Light upslope showers should develop for the north slopes of the Olympics and along the east slopes of the Cascades.
Monday looks mostly clear and cold. Strong offshore gradients will develop as the arctic high pressure slides further south... and consistently moderate to strong easterly winds are expected in the passes and at crest level Monday.
Extended Weather
Olympics, Washington Cascades near and west of the crest including Stevens, Snoqualmie, and White Passes and Mt. Hood area
Moderate rain and snow. Windy.
Light to moderate snow showers.
Decreasing scattered snow showers with partial clearing.
Mostly clear and cold. Increasing east winds Monday.
East slopes of the Washington Cascades
Light to occasionally moderate rain and snow. Windy.
Light snow showers.
Partly to mostly cloudy with scattered snow showers.
Mostly clear and cold. Increasing east winds Monday.
Extended Snow/Freezing Levels
| Mt. Baker | Snoqualmie Pass | Mt. Hood | Easterly Flow * | ||
|---|---|---|---|---|---|
| Saturday Morning - Saturday Mid-day | Snow Level | 2000' - 3000' | 3000' - 4000' | 3000' - 4000' | |
| Saturday Afternoon - Evening | Snow Level | 2000' - 3000' | 2500' - 3500' | 3000' - 4000' | |
| Saturday Night - Sunday | Snow Level | 1500' - 2500' | 1500' - 2500' | 2000' - 3000' | |
| Sunday Night - Monday | Freezing Level | 0' - 500' | 0' - 500' | 0' - 1000' |
| Mt. Baker | Elevation |
|---|---|
| Saturday Morning - Saturday Mid-day |
Snow Level 2000' - 3000' |
| Saturday Afternoon - Evening |
Snow Level 2000' - 3000' |
| Saturday Night - Sunday |
Snow Level 1500' - 2500' |
| Sunday Night - Monday |
Freezing Level 0' - 500' |
| Snoqualmie Pass | Elevation |
|---|---|
| Saturday Morning - Saturday Mid-day |
Snow Level 3000' - 4000' |
| Saturday Afternoon - Evening |
Snow Level 2500' - 3500' |
| Saturday Night - Sunday |
Snow Level 1500' - 2500' |
| Sunday Night - Monday |
Freezing Level 0' - 500' |
| Mt. Hood | Elevation |
|---|---|
| Saturday Morning - Saturday Mid-day |
Snow Level 3000' - 4000' |
| Saturday Afternoon - Evening |
Snow Level 3000' - 4000' |
| Saturday Night - Sunday |
Snow Level 2000' - 3000' |
| Sunday Night - Monday |
Freezing Level 0' - 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.
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 24, 2014
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