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
Afternoon update: Adjusted some Day 1 and Day 2 precipitation forecasts. Highlighted uncertainty to Sunday's precipitation intensity forecast in extended synopsis.
The strong ridge of high pressure that has dominated our weather pattern over the last few days has finally begun to flatten and shift east. Warm frontal moisture well out ahead of a N-S oriented front positioned offshore has begun to spread over the area early Thursday morning. Snow levels will remain elevated until the front moves through the Cascades mid-Friday afternoon. Easterly flow will not save the Passes from rain in this overall mild pattern.
After the front passes through Friday afternoon, look for snow levels to uniformly lower to around 3500-4000 feet through Friday night. Mt. Baker looks likely to pick up the most amount of water over the next 2 days. The trailing upper level longwave trough will pass through Friday night helping to maintain shower activity through the night.
Weather Forecast
Olympics and Washington Cascades near and west of the crest including Stevens, Snoqualmie, and White Passes
| Thursday |
Cloudy with periods of light rain and snow. Cloud bases lowering through the day. Mild. |
| Thursday Night - Friday Morning |
Light to occasionally moderate rain and snow, except moderate Mt. Baker area. |
| Friday Afternoon |
Light to occasionally moderate rain and snow becoming showers, except moderate to occasionally heavy Mt. Baker area. Cooling trend beginning Friday afternoon. |
| Friday Night |
Light to moderate rain and snow showers. Cooling trend. |
Mt. Hood Area
| Thursday |
Cloudy with periods of light rain and snow. Cloud bases lowering through the day. Mild. |
| Thursday Night - Friday Morning |
Cloudy with light rain and snow. |
| Friday Afternoon - Friday Night |
Light to moderate rain and snow showers tapering down Friday night. Cooling trend beginning Friday afternoon. |
East slopes of the Washington Cascades
| Thursday |
Mostly cloudy with periods of very light rain and snow. Mild. |
| Thursday Night - Friday Morning |
Cloudy with light rain and snow. |
| Friday Afternoon - Friday Night |
Light rain and snow showers, except occasionally moderate near the Cascade crest. Cooling trend beginning late Friday afternoon. |
Issued: 2:08 PM PST Thursday, February 11, 2016
Snow/Freezing Level (ft)
| Hurricane Ridge | Mt. Baker | Washington Pass | Leavenworth | Stevens Pass | Snoqualmie Pass | Mt. Rainier, Crystal & White Pass | Mt. Hood | ||
|---|---|---|---|---|---|---|---|---|---|
| Thursday Afternoon | Snow Level * | 8000' | 7000' | 6000' | ' | ' | 8000' | ' | 8500' |
| Thursday Night | Snow Level * | 7500' | 7000' | 6000' | ' | ' | 7500' | ' | 7500' |
| Friday Morning | Snow Level | 6500' | 7000' | 6000' | ' | ' | 7000' | ' | 7000' |
| Friday Afternoon | Snow Level | 4000' | 3500' | 3500' | ' | ' | 4000' | ' | 4000' |
| Friday Night | Snow Level | 3500' | 3500' | 3500' | ' | ' | 3500' | ' | 3500' |
| Hurricane Ridge | Elevation |
|---|---|
| Thursday Afternoon |
Snow Level 8000' (Easterly Flow *) |
| Thursday Night |
Snow Level 7500' (Easterly Flow *) |
| Friday Morning |
Snow Level 6500' |
| Friday Afternoon |
Snow Level 4000' |
| Friday Night |
Snow Level 3500' |
| Mt. Baker | Elevation |
|---|---|
| Thursday Afternoon |
Snow Level 7000' (Easterly Flow *) |
| Thursday Night |
Snow Level 7000' (Easterly Flow *) |
| Friday Morning |
Snow Level 7000' |
| Friday Afternoon |
Snow Level 3500' |
| Friday Night |
Snow Level 3500' |
| Washington Pass | Elevation |
|---|---|
| Thursday Afternoon |
Snow Level 6000' (Easterly Flow *) |
| Thursday Night |
Snow Level 6000' (Easterly Flow *) |
| Friday Morning |
Snow Level 6000' |
| Friday Afternoon |
Snow Level 3500' |
| Friday Night |
Snow Level 3500' |
| Leavenworth | Elevation |
|---|---|
| Thursday Afternoon |
Snow Level ' (Easterly Flow *) |
| Thursday Night |
Snow Level ' (Easterly Flow *) |
| Friday Morning |
Snow Level ' |
| Friday Afternoon |
Snow Level ' |
| Friday Night |
Snow Level ' |
| Stevens Pass | Elevation |
|---|---|
| Thursday Afternoon |
Snow Level ' (Easterly Flow *) |
| Thursday Night |
Snow Level ' (Easterly Flow *) |
| Friday Morning |
Snow Level ' |
| Friday Afternoon |
Snow Level ' |
| Friday Night |
Snow Level ' |
| Snoqualmie Pass | Elevation |
|---|---|
| Thursday Afternoon |
Snow Level 8000' (Easterly Flow *) |
| Thursday Night |
Snow Level 7500' (Easterly Flow *) |
| Friday Morning |
Snow Level 7000' |
| Friday Afternoon |
Snow Level 4000' |
| Friday Night |
Snow Level 3500' |
| Mt. Rainier & Crystal | Elevation |
|---|---|
| Thursday Afternoon |
Snow Level ' (Easterly Flow *) |
| Thursday Night |
Snow Level ' (Easterly Flow *) |
| Friday Morning |
Snow Level ' |
| Friday Afternoon |
Snow Level ' |
| Friday Night |
Snow Level ' |
| Mt. Hood | Elevation |
|---|---|
| Thursday Afternoon |
Snow Level 8500' (Easterly Flow *) |
| Thursday Night |
Snow Level 7500' (Easterly Flow *) |
| Friday Morning |
Snow Level 7000' |
| Friday Afternoon |
Snow Level 4000' |
| 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 | 0.50 - 1.00 | 0.50 - 0.75 |
| Mt Baker Ski Area | 0 - 1.00 | 1.50 - 2.00 |
| Washington Pass | 0.25 - 0.50 | 0 - 0.50 |
| Stevens Pass | 0.50 - 0.50 | 0.50 - 0.75 |
| Snoqualmie Pass | 0.50 - 0.50 | 0 - 0.75 |
| Mission Ridge | 0.25 - 0.50 | LT 0.25 |
| Crystal Mt | 0.25 - 0.50 | 0.25 - 0.50 |
| Paradise | 0.50 - 0.75 | 0.75 - 1.00 |
| White Pass | 0.25 - 0.50 | 0.25 - 0.50 |
| Mt Hood Meadows | 0.25 - 0.50 | 0.25 - 0.50 |
| Timberline | 0.25 - 0.50 | 0 - 0.50 |
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: 2:08 PM PST Thursday, February 11, 2016
Free Winds at 5000' (mph)
| Hurricane Ridge | Mt. Baker | Stevens to Snoqualmie Pass | Mt. Rainier | Mt. Hood | |
|---|---|---|---|---|---|
| Thursday Afternoon | SSW 15 - 25 | S 10 - 20 | SE 15 - 25 | --- - | S 5 - 15 |
| Thursday Night - Friday Morning | SW 15 - 30 | S 10 - 20 | S 10 - 20 | --- - | S 5 - 15 |
| Friday Afternoon | SW 15 - 25 | WSW 10 - 20 | SW 10 - 20 | --- - | WSW 10 - 20 |
| Friday Night | SW 15 - 25 | SW 10 - 20 | WSW 15 - 30 | --- - | WSW 20 - 35 |
| Hurricane Ridge | Elevation |
|---|---|
| Thursday Afternoon | SSW 15 - 25 |
| Thursday Night - Friday Morning | SW 15 - 30 |
| Friday Afternoon | SW 15 - 25 |
| Friday Night | SW 15 - 25 |
| Mt. Baker | Elevation |
|---|---|
| Thursday Afternoon | S 10 - 20 |
| Thursday Night - Friday Morning | S 10 - 20 |
| Friday Afternoon | WSW 10 - 20 |
| Friday Night | SW 10 - 20 |
| Stevens and Snoqualmie Pass | Elevation |
|---|---|
| Thursday Afternoon | SE 15 - 25 |
| Thursday Night - Friday Morning | S 10 - 20 |
| Friday Afternoon | SW 10 - 20 |
| Friday Night | WSW 15 - 30 |
| Mt. Rainier | Elevation |
|---|---|
| Thursday Afternoon | --- - |
| Thursday Night - Friday Morning | --- - |
| Friday Afternoon | --- - |
| Friday Night | --- - |
| Mt. Hood | Elevation |
|---|---|
| Thursday Afternoon | S 5 - 15 |
| Thursday Night - Friday Morning | S 5 - 15 |
| Friday Afternoon | WSW 10 - 20 |
| Friday Night | WSW 20 - 35 |
| Hurricane Ridge | Direction - Speed |
|---|---|
| Thursday Afternoon | SSW 15 - 25 |
| Thursday Night - Friday Morning | SW 15 - 30 |
| Friday Afternoon | SW 15 - 25 |
| Friday Night | SW 15 - 25 |
| Mt. Baker | Direction - Speed |
|---|---|
| Thursday Afternoon | S 10 - 20 |
| Thursday Night - Friday Morning | S 10 - 20 |
| Friday Afternoon | WSW 10 - 20 |
| Friday Night | SW 10 - 20 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Thursday Afternoon | SE 15 - 25 |
| Thursday Night - Friday Morning | S 10 - 20 |
| Friday Afternoon | SW 10 - 20 |
| Friday Night | WSW 15 - 30 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Thursday Afternoon | --- - |
| Thursday Night - Friday Morning | --- - |
| Friday Afternoon | --- - |
| Friday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| Thursday Afternoon | S 5 - 15 |
| Thursday Night - Friday Morning | S 5 - 15 |
| Friday Afternoon | WSW 10 - 20 |
| Friday Night | WSW 20 - 35 |
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 Afternoon | SW 20 - 30 | SW 10 - 20 | SW 25 - 35 | --- - | SW 30 - 40 |
| Thursday Night - Friday Morning | SW 25 - 40 | SW 20 - 35 | SW 25 - 35 | --- - | SW 25 - 40 |
| Friday Afternoon | SW 35 - 50 | SW 40 - 50 | SW 35 - 45 | --- - | SW 40 - 60 |
| Friday Night | SW 15 - 25 | WSW 20 - 30 | WSW 30 - 40 | --- - | W 35 - 50 |
| Mt. Baker | Direction - Speed |
|---|---|
| Thursday Afternoon | SW 20 - 30 |
| Thursday Night - Friday Morning | SW 25 - 40 |
| Friday Afternoon | SW 35 - 50 |
| Friday Night | SW 15 - 25 |
| Washington Pass | Direction - Speed |
|---|---|
| Thursday Afternoon | SW 10 - 20 |
| Thursday Night - Friday Morning | SW 20 - 35 |
| Friday Afternoon | SW 40 - 50 |
| Friday Night | WSW 20 - 30 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Thursday Afternoon | SW 25 - 35 |
| Thursday Night - Friday Morning | SW 25 - 35 |
| Friday Afternoon | SW 35 - 45 |
| Friday Night | WSW 30 - 40 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Thursday Afternoon | --- - |
| Thursday Night - Friday Morning | --- - |
| Friday Afternoon | --- - |
| Friday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| Thursday Afternoon | SW 30 - 40 |
| Thursday Night - Friday Morning | SW 25 - 40 |
| Friday Afternoon | SW 40 - 60 |
| Friday Night | W 35 - 50 |
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: 2:08 PM PST Thursday, February 11, 2016
Extended Weather Synopsis for Sunday night through Sunday
Shower activity should wane through mid-day Saturday before the next system, an occluded front, moves in by later Saturday afternoon. Snow levels will initially stay cool but will begin to rise Saturday evening as precipitation intensity increases.
Another warm front will pass through on Sunday, nudging snow levels higher once again as strong high pressure becomes re-established offshore around 135 W. There is a fair amount of uncertainty just how much moisture will ride up and over the ridge and into the PNW on Sunday. This forecast favors a the drier GFS solution, although several forecast models show a subtropcial tap of moisture directed into the area during the day Sunday, with heavy precipitation for the west slopes of the Olympics and Cascades.
The axis of the heaviest precipitation in this pattern will shift north into British Columbia on Monday as the ridge continues to build.
Extended Weather
Olympics, Washington Cascades and Mt. Hood
Cloudy with scattered light rain and snow showers becoming steady light rain and snow in the afternoon. Cooler.
Moderate rain and snow becoming moderate showers overnight. Warming trend.
Cloudy with light rain and snow. Mild.
Moderate to occasionally heavy rain and snow. Mild.
Mostly cloudy with periods of light rain and snow south Washington Cascades and Mt. Hood. Cloudy with moderate rain and snow north Cascades and Olympics. Mild.
Extended Snow/Freezing Levels
| Mt. Baker | Snoqualmie Pass | Mt. Hood | Easterly Flow * | ||
|---|---|---|---|---|---|
| Saturday | Snow Level | 3000' - 4000' | 3000' - 4000' | 3500' - 4500' | |
| Saturday Night | Snow Level | 5000' - 6000' | 5000' - 6000' | 6500' - 7500' | |
| Sunday | Snow Level | 5000' - 6000' | 6000' - 7000' | 7000' - 8000' | |
| Sunday Night - Monday | Snow Level | 6000' - 7500' | 6000' - 7500' | 6500' - 7500' |
| Mt. Baker | Elevation |
|---|---|
| Saturday |
Snow Level 3000' - 4000' |
| Saturday Night |
Snow Level 5000' - 6000' |
| Sunday |
Snow Level 5000' - 6000' |
| Sunday Night - Monday |
Snow Level 6000' - 7500' |
| Snoqualmie Pass | Elevation |
|---|---|
| Saturday |
Snow Level 3000' - 4000' |
| Saturday Night |
Snow Level 5000' - 6000' |
| Sunday |
Snow Level 6000' - 7000' |
| Sunday Night - Monday |
Snow Level 6000' - 7500' |
| Mt. Hood | Elevation |
|---|---|
| Saturday |
Snow Level 3500' - 4500' |
| Saturday Night |
Snow Level 6500' - 7500' |
| Sunday |
Snow Level 7000' - 8000' |
| Sunday Night - Monday |
Snow Level 6500' - 7500' |
* 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 Feb 11, 2016
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