Jump to: Weather Forecast I Snow/Freezing Level I Precipitation I Free Winds 5k I Free Winds 9k
Weather Synopsis for Saturday & Sunday
A sharp trough cam through last night. On Saturday that trough has moved to the Great Basin. To our west, a flat ridge off the California coast will allow a moist flow to ride over the top on a westerly jetstream aimed at the southern British Columbia coastline. A warm front will begin over-running the cold air in place as it approaches our region today and tonight, but moisture will make limited progress into our region. The warming will be particularly sharp overnight in the Olympics, with modest warming elsewhere.
On Sunday, the warm frontal rain/snow band arrives and the warming continues as our forecast area will be on the warm side of the storm. However, slight easterly flow at the surface will keep Snoqualmie and Stevens Passes cold enough for initial snow before an eventual transition to rain (timing uncertain).
Sunday night, the modest cold front drops south and west through our region, beginning to cut off the moisture source as the front sags south, and bringing a slight cooling trend.
Weather Forecast
Olympics
| Saturday | Cloudy with increasing light snow. |
| Saturday Night | Increasing light to moderate rain and snow. |
| Sunday | Increasing light to moderate rain and snow. |
| Sunday Night | Decreasing light to moderate rain and snow. |
Washington Cascades near and west of the Crest including Stevens, Snoqualmie and White Passes
| Saturday | Light snow showers between Snoqualmie and Stevens Pass, ending. Decreasing pass-level clouds will be replaced by increasing mid-level and high-level clouds. |
| Saturday Night | Increasing light rain and snow north, heavier in the north and mainly after midnight. |
| Sunday | Increasing light rain and snow in the morning becoming moderate central and north. Increasing light to moderate rain and snow by afternoon in the south. |
| Sunday Night | Moderate rain and snow ending north. Continued moderate to heavy rain and snow central. Increasing moderate to heavy rain and snow south. |
East Slopes of the Washington Cascades
| Saturday | Increasing mid-level and high-level clouds. |
| Saturday Night | Increasing light snow north and central. |
| Sunday | Increasing light to moderate moderate rain and snow north and central; becoming light in the south. |
| Sunday Night | Decreasing light to moderate rain and snow. |
Mt. Hood
| Saturday | Light showers ending in the morning. Increasing mid and high-level clouds in the afternoon. |
| Saturday Night | Increasing light rain and snow by morning. |
| Sunday | Light rain and snow. |
| Sunday Night | Increasing light rain and snow. |
Issued: 7:41 AM PST Saturday, December 16, 2017
Snow/Freezing Level (ft)
| Hurricane Ridge | Mt. Baker | Washington Pass | Leavenworth | Stevens Pass | Snoqualmie Pass | Mt. Rainier, Crystal & White Pass | Mt. Hood | ||
|---|---|---|---|---|---|---|---|---|---|
| Saturday Morning | Snow Level | 2500' | 1500' | 1500' | ' | ' | 1500' | ' | 2000' |
| Saturday Afternoon | Snow Level | 2500' | 2000' | 1500' | ' | ' | 2000' | ' | 2500' |
| Saturday Night | Snow Level * | 7000' | 3000' | 2500' | ' | ' | 3500' | ' | 3500' |
| Sunday Morning | Snow Level * | 6000' | 3500' | 3000' | ' | ' | 4000' | ' | 6500' |
| Sunday Afternoon | Snow Level | 6000' | 4500' | 4000' | ' | ' | 5500' | ' | 7000' |
| Sunday Night | Snow Level | 5500' | 4500' | 4500' | ' | ' | 5500' | ' | 7000' |
| Hurricane Ridge | Elevation |
|---|---|
| Saturday Morning |
Snow Level 2500' |
| Saturday Afternoon |
Snow Level 2500' |
| Saturday Night |
Snow Level 7000' (Easterly Flow *) |
| Sunday Morning |
Snow Level 6000' (Easterly Flow *) |
| Sunday Afternoon |
Snow Level 6000' |
| Sunday Night |
Snow Level 5500' |
| Mt. Baker | Elevation |
|---|---|
| Saturday Morning |
Snow Level 1500' |
| Saturday Afternoon |
Snow Level 2000' |
| Saturday Night |
Snow Level 3000' (Easterly Flow *) |
| Sunday Morning |
Snow Level 3500' (Easterly Flow *) |
| Sunday Afternoon |
Snow Level 4500' |
| Sunday Night |
Snow Level 4500' |
| Washington Pass | Elevation |
|---|---|
| Saturday Morning |
Snow Level 1500' |
| Saturday Afternoon |
Snow Level 1500' |
| Saturday Night |
Snow Level 2500' (Easterly Flow *) |
| Sunday Morning |
Snow Level 3000' (Easterly Flow *) |
| Sunday Afternoon |
Snow Level 4000' |
| Sunday Night |
Snow Level 4500' |
| Leavenworth | Elevation |
|---|---|
| Saturday Morning |
Snow Level ' |
| Saturday Afternoon |
Snow Level ' |
| Saturday Night |
Snow Level ' (Easterly Flow *) |
| Sunday Morning |
Snow Level ' (Easterly Flow *) |
| Sunday Afternoon |
Snow Level ' |
| Sunday Night |
Snow Level ' |
| Stevens Pass | Elevation |
|---|---|
| Saturday Morning |
Snow Level ' |
| Saturday Afternoon |
Snow Level ' |
| Saturday Night |
Snow Level ' (Easterly Flow *) |
| Sunday Morning |
Snow Level ' (Easterly Flow *) |
| Sunday Afternoon |
Snow Level ' |
| Sunday Night |
Snow Level ' |
| Snoqualmie Pass | Elevation |
|---|---|
| Saturday Morning |
Snow Level 1500' |
| Saturday Afternoon |
Snow Level 2000' |
| Saturday Night |
Snow Level 3500' (Easterly Flow *) |
| Sunday Morning |
Snow Level 4000' (Easterly Flow *) |
| Sunday Afternoon |
Snow Level 5500' |
| Sunday Night |
Snow Level 5500' |
| Mt. Rainier & Crystal | Elevation |
|---|---|
| Saturday Morning |
Snow Level ' |
| Saturday Afternoon |
Snow Level ' |
| Saturday Night |
Snow Level ' (Easterly Flow *) |
| Sunday Morning |
Snow Level ' (Easterly Flow *) |
| Sunday Afternoon |
Snow Level ' |
| Sunday Night |
Snow Level ' |
| Mt. Hood | Elevation |
|---|---|
| Saturday Morning |
Snow Level 2000' |
| Saturday Afternoon |
Snow Level 2500' |
| Saturday Night |
Snow Level 3500' (Easterly Flow *) |
| Sunday Morning |
Snow Level 6500' (Easterly Flow *) |
| Sunday Afternoon |
Snow Level 7000' |
| Sunday Night |
Snow Level 7000' |
* 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 0.25 | 0.25 - 0.50 |
| Mt Baker Ski Area | LT 0.10 | 1.00 - 1.50 |
| Washington Pass | LT 0.10 | 0 - 0.50 |
| Stevens Pass | LT 0.10 | 0 - 1.50 |
| Snoqualmie Pass | LT 0.10 | 1.50 - 2.00 |
| Mission Ridge | LT 0.10 | LT 0.25 |
| Crystal Mt | LT 0.10 | 0.25 - 0.50 |
| Paradise | LT 0.10 | 0 - 1.00 |
| White Pass | LT 0.10 | 0 - 0.50 |
| Mt Hood Meadows | LT 0.10 | LT 0.25 |
| Timberline | LT 0.10 | LT 0.25 |
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: 7:41 AM PST Saturday, December 16, 2017
Free Winds at 5000' (mph)
| Hurricane Ridge | Mt. Baker | Stevens to Snoqualmie Pass | Mt. Rainier | Mt. Hood | |
|---|---|---|---|---|---|
| Saturday Morning | W 10 - 20 | SW 5 - 15 | W 10 - 20 | --- - | WNW 20 - 30 |
| Saturday Afternoon | W 5 - 15 | SW 5 - 15 | W 10 - 20 | --- - | WNW 15 - 25 |
| Saturday Night | SW 20 - 30 | SSW 15 - 25 | WSW 20 - 30 | --- - | W 15 - 25 |
| Sunday Morning | WSW 20 - 30 | SSW 20 - 30 | WSW 25 - 35 | --- - | WSW 25 - 35 |
| Sunday Afternoon | WSW 25 - 35 | SW 25 - 35 | WSW 30 - 40 | --- - | WSW 25 - 35 |
| Sunday Night | W 20 - 30 | WSW 20 - 30 | W 30 - 40 | --- - | W 30 - 40 |
| Hurricane Ridge | Elevation |
|---|---|
| Saturday Morning | W 10 - 20 |
| Saturday Afternoon | W 5 - 15 |
| Saturday Night | SW 20 - 30 |
| Sunday Morning | WSW 20 - 30 |
| Sunday Afternoon | WSW 25 - 35 |
| Sunday Night | W 20 - 30 |
| Mt. Baker | Elevation |
|---|---|
| Saturday Morning | SW 5 - 15 |
| Saturday Afternoon | SW 5 - 15 |
| Saturday Night | SSW 15 - 25 |
| Sunday Morning | SSW 20 - 30 |
| Sunday Afternoon | SW 25 - 35 |
| Sunday Night | WSW 20 - 30 |
| Stevens and Snoqualmie Pass | Elevation |
|---|---|
| Saturday Morning | W 10 - 20 |
| Saturday Afternoon | W 10 - 20 |
| Saturday Night | WSW 20 - 30 |
| Sunday Morning | WSW 25 - 35 |
| Sunday Afternoon | WSW 30 - 40 |
| Sunday Night | W 30 - 40 |
| Mt. Rainier | Elevation |
|---|---|
| Saturday Morning | --- - |
| Saturday Afternoon | --- - |
| Saturday Night | --- - |
| Sunday Morning | --- - |
| Sunday Afternoon | --- - |
| Sunday Night | --- - |
| Mt. Hood | Elevation |
|---|---|
| Saturday Morning | WNW 20 - 30 |
| Saturday Afternoon | WNW 15 - 25 |
| Saturday Night | W 15 - 25 |
| Sunday Morning | WSW 25 - 35 |
| Sunday Afternoon | WSW 25 - 35 |
| Sunday Night | W 30 - 40 |
| Hurricane Ridge | Direction - Speed |
|---|---|
| Saturday Morning | W 10 - 20 |
| Saturday Afternoon | W 5 - 15 |
| Saturday Night | SW 20 - 30 |
| Sunday Morning | WSW 20 - 30 |
| Sunday Afternoon | WSW 25 - 35 |
| Sunday Night | W 20 - 30 |
| Mt. Baker | Direction - Speed |
|---|---|
| Saturday Morning | SW 5 - 15 |
| Saturday Afternoon | SW 5 - 15 |
| Saturday Night | SSW 15 - 25 |
| Sunday Morning | SSW 20 - 30 |
| Sunday Afternoon | SW 25 - 35 |
| Sunday Night | WSW 20 - 30 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Saturday Morning | W 10 - 20 |
| Saturday Afternoon | W 10 - 20 |
| Saturday Night | WSW 20 - 30 |
| Sunday Morning | WSW 25 - 35 |
| Sunday Afternoon | WSW 30 - 40 |
| Sunday Night | W 30 - 40 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Saturday Morning | --- - |
| Saturday Afternoon | --- - |
| Saturday Night | --- - |
| Sunday Morning | --- - |
| Sunday Afternoon | --- - |
| Sunday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| Saturday Morning | WNW 20 - 30 |
| Saturday Afternoon | WNW 15 - 25 |
| Saturday Night | W 15 - 25 |
| Sunday Morning | WSW 25 - 35 |
| Sunday Afternoon | WSW 25 - 35 |
| Sunday Night | W 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.
Free Winds at 9000' (mph)
| Mt. Baker | Washington Pass | Stevens to Snoqualmie Pass | Mt. Rainier | Mt. Hood | |
|---|---|---|---|---|---|
| Saturday Morning | WNW 20 - 30 | WNW 15 - 25 | WNW 35 - 45 | --- - | NW 40 - 50 |
| Saturday Afternoon | WNW 20 - 30 | WNW 15 - 25 | NW 30 - 40 | --- - | NNW 25 - 35 |
| Saturday Night | WSW 35 - 45 | WSW 30 - 40 | W 35 - 45 | --- - | WNW 25 - 35 |
| Sunday Morning | WSW 35 - 45 | WSW 40 - 50 | W 40 - 50 | --- - | WNW 25 - 35 |
| Sunday Afternoon | WSW 45 - 55 | WSW 45 - 55 | WSW 45 - 55 | --- - | W 40 - 50 |
| Sunday Night | WSW 45 - 55 | WSW 50 - 55 | WSW 50 - 60 | --- - | W 50 - 60 |
| Mt. Baker | Direction - Speed |
|---|---|
| Saturday Morning | WNW 20 - 30 |
| Saturday Afternoon | WNW 20 - 30 |
| Saturday Night | WSW 35 - 45 |
| Sunday Morning | WSW 35 - 45 |
| Sunday Afternoon | WSW 45 - 55 |
| Sunday Night | WSW 45 - 55 |
| Washington Pass | Direction - Speed |
|---|---|
| Saturday Morning | WNW 15 - 25 |
| Saturday Afternoon | WNW 15 - 25 |
| Saturday Night | WSW 30 - 40 |
| Sunday Morning | WSW 40 - 50 |
| Sunday Afternoon | WSW 45 - 55 |
| Sunday Night | WSW 50 - 55 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Saturday Morning | WNW 35 - 45 |
| Saturday Afternoon | NW 30 - 40 |
| Saturday Night | W 35 - 45 |
| Sunday Morning | W 40 - 50 |
| Sunday Afternoon | WSW 45 - 55 |
| Sunday Night | WSW 50 - 60 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Saturday Morning | --- - |
| Saturday Afternoon | --- - |
| Saturday Night | --- - |
| Sunday Morning | --- - |
| Sunday Afternoon | --- - |
| Sunday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| Saturday Morning | NW 40 - 50 |
| Saturday Afternoon | NNW 25 - 35 |
| Saturday Night | WNW 25 - 35 |
| Sunday Morning | WNW 25 - 35 |
| Sunday Afternoon | W 40 - 50 |
| Sunday Night | W 50 - 60 |
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.
Jump to: Weather Forecast I Snow/Freezing Level I Precipitation I Free Winds 5k I Free Winds 9k
Previous forecast from Dec 14, 2017
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