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 night through Tuesday
An unusually high-amplitude December ridge continues to dominate the forecast, bringing an unusually dry start to December. The ridge axis continues to shift east as a weakening disturbance approaches the coast Wednesday night and arrives on Thursday. A very sharp temperature and pressure gradient across the Cascades begins to relax/weaken as the warm air continues to erode and thin the cold air pool east of the Cascade Crest. This means that except in valleys east of the Cascade Crest and at near pass-level at the Cascade Crest, expect unseasonably mild weather to continue. If you are within the shallow cold air pool, temperatures may range from the teens to the low thirties, while elsewhere expect temperatures in the thirties and forties. E winds through the mountain gaps and S winds aloft should also gradually relent overnight following some very strong winds at Crystal, White Pass, and Alpental summits.
Mid or high-level clouds should begin to work into the region early on Thursday as the weakening front approaches and brings some very slight cooling aloft and temporary respite from the E flow. The last dregs of the system may bring a light sprinkle to Hurricane Ridge Thursday afternoon or a sprinkle to parts of the west slopes of the Cascades Thursday evening. Skies should become increasingly clear late Thursday night.
On Friday, the ridge rebounds and we're back to 11,000 ft freezing levels across the region with sunny skies with light E flow once again increasing.
Weather Forecast
Hurricane Ridge
| Wednesday Night | Mostly clear. Very mild. Light winds. |
| Thursday | Partly cloudy with increasing clouds and a chance of a light sprinkle. Mild. Light winds. |
Mt. Baker
| Wednesday Night | Mostly clear. Very mild. Decreasing moderate winds in the alpine. |
| Thursday | Mostly sunny in the morning, with increasing high clouds during the afternoon. Mild. Light winds. |
Washington Pass and Leavenworth
| Wednesday Night | Mostly clear. Mild in the alpine with a cold pool persisting below 5000 ft. Decreasing moderate winds in the alpine. |
| Thursday | Mostly sunny in the morning with high clouds increasing in the afternoon. Mild in the alpine with a thinning cold pool below 4000 ft. Light winds. |
Stevens and Snoqualmie Pass
| Wednesday Night | Mostly clear. Mild in the alpine with E winds keeping temperatures cool below 5000 ft. Decreasing moderate 5000 ft and E pass-level winds in the evening, then becoming light. |
| Thursday | Mostly sunny in the morning with high clouds increasing in the afternoon. Inversion early in the day, then mild temperatures at all elevations. Light 5000 ft winds and decreasing light E winds at pass level. |
Mt. Rainier, Crystal and White Pass
| Wednesday Night | Mostly clear. Mild in the alpine and west of the Cascade Crest with E winds keeping temperatures cool below 5000 ft at Crystal, Chinook and White Pass. Moderate winds gusting strong in the early evening at locations exposed to E flow, such as Crystal and White Pass upper lift stations, then decreasing. Lighter winds in other locations. |
| Thursday | Mostly sunny in the morning with high clouds increasing in the afternoon. Inversion early in the day, then mild temperatures at all elevations. Light 5000 ft winds and decreasing light E winds at pass level. |
Mt. Hood
| Wednesday Night | Mostly clear and mild with a shallow cold air pool developing on the E side of the mountain below 5000 ft. Decreasing light to moderate winds. |
| Thursday | Mostly sunny and mild in the morning with high clouds increasing. Light winds. |
Issued: 2:13 PM PST Wednesday, December 2, 2020
Snow/Freezing Level (ft)
| Hurricane Ridge | Mt. Baker | Washington Pass | Leavenworth | Stevens Pass | Snoqualmie Pass | Mt. Rainier, Crystal & White Pass | Mt. Hood | ||
|---|---|---|---|---|---|---|---|---|---|
| Wednesday Evening | Freezing Level * | 11500' | 11500' | 11500' | 11500' | 11500' | 11500' | 11500' | 11500' |
| Wednesday Night | Freezing Level * | 11000' | 11000' | 11000' | 11500' | 11500' | 11500' | 11500' | 12000' |
| Thursday Morning | Freezing Level * | 10500' | 10500' | 11000' | 11000' | 11000' | 11000' | 11000' | 11500' |
| Thursday Afternoon | Freezing Level * | 9000' | 9500' | 10500' | 11000' | 10500' | 10500' | 10500' | 11000' |
| Thursday Evening | Freezing Level * | 8500' | 8000' | 8500' | 8500' | 8500' | 8500' | 8500' | 9000' |
| Thursday Night | Freezing Level * | 9500' | 10000' | 9500' | 9000' | 9000' | 9500' | 9500' | 9000' |
| Friday Morning | Freezing Level * | 9000' | 10500' | 10500' | 10500' | 10500' | 10500' | 10500' | 10500' |
| Friday Afternoon | Freezing Level * | 10000' | 11000' | 11000' | 11000' | 11000' | 11000' | 11000' | 11000' |
| Hurricane Ridge | Elevation |
|---|---|
| Wednesday Evening |
Freezing Level 11500' (Easterly Flow *) |
| Wednesday Night |
Freezing Level 11000' (Easterly Flow *) |
| Thursday Morning |
Freezing Level 10500' (Easterly Flow *) |
| Thursday Afternoon |
Freezing Level 9000' (Easterly Flow *) |
| Thursday Evening |
Freezing Level 8500' (Easterly Flow *) |
| Thursday Night |
Freezing Level 9500' (Easterly Flow *) |
| Friday Morning |
Freezing Level 9000' (Easterly Flow *) |
| Friday Afternoon |
Freezing Level 10000' (Easterly Flow *) |
| Mt. Baker | Elevation |
|---|---|
| Wednesday Evening |
Freezing Level 11500' (Easterly Flow *) |
| Wednesday Night |
Freezing Level 11000' (Easterly Flow *) |
| Thursday Morning |
Freezing Level 10500' (Easterly Flow *) |
| Thursday Afternoon |
Freezing Level 9500' (Easterly Flow *) |
| Thursday Evening |
Freezing Level 8000' (Easterly Flow *) |
| Thursday Night |
Freezing Level 10000' (Easterly Flow *) |
| Friday Morning |
Freezing Level 10500' (Easterly Flow *) |
| Friday Afternoon |
Freezing Level 11000' (Easterly Flow *) |
| Washington Pass | Elevation |
|---|---|
| Wednesday Evening |
Freezing Level 11500' (Easterly Flow *) |
| Wednesday Night |
Freezing Level 11000' (Easterly Flow *) |
| Thursday Morning |
Freezing Level 11000' (Easterly Flow *) |
| Thursday Afternoon |
Freezing Level 10500' (Easterly Flow *) |
| Thursday Evening |
Freezing Level 8500' (Easterly Flow *) |
| Thursday Night |
Freezing Level 9500' (Easterly Flow *) |
| Friday Morning |
Freezing Level 10500' (Easterly Flow *) |
| Friday Afternoon |
Freezing Level 11000' (Easterly Flow *) |
| Leavenworth | Elevation |
|---|---|
| Wednesday Evening |
Freezing Level 11500' (Easterly Flow *) |
| Wednesday Night |
Freezing Level 11500' (Easterly Flow *) |
| Thursday Morning |
Freezing Level 11000' (Easterly Flow *) |
| Thursday Afternoon |
Freezing Level 11000' (Easterly Flow *) |
| Thursday Evening |
Freezing Level 8500' (Easterly Flow *) |
| Thursday Night |
Freezing Level 9000' (Easterly Flow *) |
| Friday Morning |
Freezing Level 10500' (Easterly Flow *) |
| Friday Afternoon |
Freezing Level 11000' (Easterly Flow *) |
| Stevens Pass | Elevation |
|---|---|
| Wednesday Evening |
Freezing Level 11500' (Easterly Flow *) |
| Wednesday Night |
Freezing Level 11500' (Easterly Flow *) |
| Thursday Morning |
Freezing Level 11000' (Easterly Flow *) |
| Thursday Afternoon |
Freezing Level 10500' (Easterly Flow *) |
| Thursday Evening |
Freezing Level 8500' (Easterly Flow *) |
| Thursday Night |
Freezing Level 9000' (Easterly Flow *) |
| Friday Morning |
Freezing Level 10500' (Easterly Flow *) |
| Friday Afternoon |
Freezing Level 11000' (Easterly Flow *) |
| Snoqualmie Pass | Elevation |
|---|---|
| Wednesday Evening |
Freezing Level 11500' (Easterly Flow *) |
| Wednesday Night |
Freezing Level 11500' (Easterly Flow *) |
| Thursday Morning |
Freezing Level 11000' (Easterly Flow *) |
| Thursday Afternoon |
Freezing Level 10500' (Easterly Flow *) |
| Thursday Evening |
Freezing Level 8500' (Easterly Flow *) |
| Thursday Night |
Freezing Level 9500' (Easterly Flow *) |
| Friday Morning |
Freezing Level 10500' (Easterly Flow *) |
| Friday Afternoon |
Freezing Level 11000' (Easterly Flow *) |
| Mt. Rainier & Crystal | Elevation |
|---|---|
| Wednesday Evening |
Freezing Level 11500' (Easterly Flow *) |
| Wednesday Night |
Freezing Level 11500' (Easterly Flow *) |
| Thursday Morning |
Freezing Level 11000' (Easterly Flow *) |
| Thursday Afternoon |
Freezing Level 10500' (Easterly Flow *) |
| Thursday Evening |
Freezing Level 8500' (Easterly Flow *) |
| Thursday Night |
Freezing Level 9500' (Easterly Flow *) |
| Friday Morning |
Freezing Level 10500' (Easterly Flow *) |
| Friday Afternoon |
Freezing Level 11000' (Easterly Flow *) |
| Mt. Hood | Elevation |
|---|---|
| Wednesday Evening |
Freezing Level 11500' (Easterly Flow *) |
| Wednesday Night |
Freezing Level 12000' (Easterly Flow *) |
| Thursday Morning |
Freezing Level 11500' (Easterly Flow *) |
| Thursday Afternoon |
Freezing Level 11000' (Easterly Flow *) |
| Thursday Evening |
Freezing Level 9000' (Easterly Flow *) |
| Thursday Night |
Freezing Level 9000' (Easterly Flow *) |
| Friday Morning |
Freezing Level 10500' (Easterly Flow *) |
| Friday Afternoon |
Freezing Level 11000' (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
| Wednesday Night | Tuesday | Tuesday Night | Tuesday | |
|---|---|---|---|---|
| 4 pm - 4 am | 4 am - 4 pm | 4 pm - 4 am | 4 am - 4 pm | |
| Hurricane Ridge | 0 | LT 0.10 | 0 | 0 |
| Mt Baker Ski Area | 0 | 0 | 0 | 0 |
| Washington Pass | 0 | 0 | 0 | 0 |
| Leavenworth | 0 | 0 | 0 | 0 |
| Stevens Pass | 0 | 0 | 0 | 0 |
| Snoqualmie Pass | 0 | 0 | 0 | 0 |
| Mission Ridge | 0 | 0 | 0 | 0 |
| Crystal Mt | 0 | 0 | LT 0.10 | 0 |
| Paradise | 0 | 0 | 0 | 0 |
| White Pass | 0 | 0 | 0 | 0 |
| Mt Hood Meadows | 0 | 0 | 0 | 0 |
| Timberline | 0 | 0 | 0 | 0 |
| Hurricane Ridge | Precipitation Forecast |
|---|---|
| Wednesday Night | 0 |
| Tuesday | LT 0.10 |
| Tuesday Night | 0 |
| Tuesday | 0 |
| Mt Baker Ski Area | Precipitation Forecast |
|---|---|
| Wednesday Night | 0 |
| Tuesday | 0 |
| Tuesday Night | 0 |
| Tuesday | 0 |
| Washington Pass | Precipitation Forecast |
|---|---|
| Wednesday Night | 0 |
| Tuesday | 0 |
| Tuesday Night | 0 |
| Tuesday | 0 |
| Leavenworth | Precipitation Forecast |
|---|---|
| Wednesday Night | 0 |
| Tuesday | 0 |
| Tuesday Night | 0 |
| Tuesday | 0 |
| Stevens Pass | Precipitation Forecast |
|---|---|
| Wednesday Night | 0 |
| Tuesday | 0 |
| Tuesday Night | 0 |
| Tuesday | 0 |
| Snoqualmie Pass | Precipitation Forecast |
|---|---|
| Wednesday Night | 0 |
| Tuesday | 0 |
| Tuesday Night | 0 |
| Tuesday | 0 |
| Mission Ridge | Precipitation Forecast |
|---|---|
| Wednesday Night | 0 |
| Tuesday | 0 |
| Tuesday Night | 0 |
| Tuesday | 0 |
| Crystal Mt | Precipitation Forecast |
|---|---|
| Wednesday Night | 0 |
| Tuesday | 0 |
| Tuesday Night | LT 0.10 |
| Tuesday | 0 |
| Paradise | Precipitation Forecast |
|---|---|
| Wednesday Night | 0 |
| Tuesday | 0 |
| Tuesday Night | 0 |
| Tuesday | 0 |
| White Pass | Precipitation Forecast |
|---|---|
| Wednesday Night | 0 |
| Tuesday | 0 |
| Tuesday Night | 0 |
| Tuesday | 0 |
| Mt Hood Meadows | Precipitation Forecast |
|---|---|
| Wednesday Night | 0 |
| Tuesday | 0 |
| Tuesday Night | 0 |
| Tuesday | 0 |
| Timberline | Precipitation Forecast |
|---|---|
| Wednesday Night | 0 |
| Tuesday | 0 |
| Tuesday Night | 0 |
| Tuesday | 0 |
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: 2:13 PM PST Wednesday, December 2, 2020
Free Winds at 5000' (mph)
| Hurricane Ridge | Mt. Baker | Stevens to Snoqualmie Pass | Mt. Rainier | Mt. Hood | |
|---|---|---|---|---|---|
| Wednesday Evening | S 5 - 15 | SE 5 - 15 | ESE 10 - 20 | SE 10 - 20 | SE 10 - 20 |
| Wednesday Night | S 5 - 15 | S 5 - 15 | E 0 - 10 | SE 0 - 10 | SSE 5 - 15 |
| Thursday Morning | SW 0 - 10 | SW 0 - 10 | WSW 0 - 10 | WSW 0 - 10 | SW 0 - 10 |
| Thursday Afternoon | WSW 0 - 10 | SW 0 - 10 | WSW 0 - 10 | W 0 - 10 | W 0 - 10 |
| Hurricane Ridge | Elevation |
|---|---|
| Wednesday Evening | S 5 - 15 |
| Wednesday Night | S 5 - 15 |
| Thursday Morning | SW 0 - 10 |
| Thursday Afternoon | WSW 0 - 10 |
| Mt. Baker | Elevation |
|---|---|
| Wednesday Evening | SE 5 - 15 |
| Wednesday Night | S 5 - 15 |
| Thursday Morning | SW 0 - 10 |
| Thursday Afternoon | SW 0 - 10 |
| Stevens and Snoqualmie Pass | Elevation |
|---|---|
| Wednesday Evening | ESE 10 - 20 |
| Wednesday Night | E 0 - 10 |
| Thursday Morning | WSW 0 - 10 |
| Thursday Afternoon | WSW 0 - 10 |
| Mt. Rainier | Elevation |
|---|---|
| Wednesday Evening | SE 10 - 20 |
| Wednesday Night | SE 0 - 10 |
| Thursday Morning | WSW 0 - 10 |
| Thursday Afternoon | W 0 - 10 |
| Mt. Hood | Elevation |
|---|---|
| Wednesday Evening | SE 10 - 20 |
| Wednesday Night | SSE 5 - 15 |
| Thursday Morning | SW 0 - 10 |
| Thursday Afternoon | W 0 - 10 |
| Hurricane Ridge | Direction - Speed |
|---|---|
| Wednesday Evening | S 5 - 15 |
| Wednesday Night | S 5 - 15 |
| Thursday Morning | SW 0 - 10 |
| Thursday Afternoon | WSW 0 - 10 |
| Mt. Baker | Direction - Speed |
|---|---|
| Wednesday Evening | SE 5 - 15 |
| Wednesday Night | S 5 - 15 |
| Thursday Morning | SW 0 - 10 |
| Thursday Afternoon | SW 0 - 10 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Wednesday Evening | ESE 10 - 20 |
| Wednesday Night | E 0 - 10 |
| Thursday Morning | WSW 0 - 10 |
| Thursday Afternoon | WSW 0 - 10 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Wednesday Evening | SE 10 - 20 |
| Wednesday Night | SE 0 - 10 |
| Thursday Morning | WSW 0 - 10 |
| Thursday Afternoon | W 0 - 10 |
| Mt. Hood | Direction - Speed |
|---|---|
| Wednesday Evening | SE 10 - 20 |
| Wednesday Night | SSE 5 - 15 |
| Thursday Morning | SW 0 - 10 |
| Thursday Afternoon | W 0 - 10 |
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 Evening | S 15 - 25 | SSW 15 - 25 | SSW 15 - 25 | SSW 10 - 20 | SSW 10 - 20 |
| Wednesday Night | SSW 15 - 25 | SSW 10 - 20 | SSW 10 - 20 | SSW 10 - 20 | SW 10 - 20 |
| Thursday Morning | WSW 10 - 20 | SW 10 - 20 | WSW 10 - 20 | WSW 10 - 20 | WSW 10 - 20 |
| Thursday Afternoon | WSW 10 - 20 | WSW 10 - 20 | W 15 - 25 | W 10 - 20 | WSW 10 - 20 |
| Mt. Baker | Direction - Speed |
|---|---|
| Wednesday Evening | S 15 - 25 |
| Wednesday Night | SSW 15 - 25 |
| Thursday Morning | WSW 10 - 20 |
| Thursday Afternoon | WSW 10 - 20 |
| Washington Pass | Direction - Speed |
|---|---|
| Wednesday Evening | SSW 15 - 25 |
| Wednesday Night | SSW 10 - 20 |
| Thursday Morning | SW 10 - 20 |
| Thursday Afternoon | WSW 10 - 20 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Wednesday Evening | SSW 15 - 25 |
| Wednesday Night | SSW 10 - 20 |
| Thursday Morning | WSW 10 - 20 |
| Thursday Afternoon | W 15 - 25 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Wednesday Evening | SSW 10 - 20 |
| Wednesday Night | SSW 10 - 20 |
| Thursday Morning | WSW 10 - 20 |
| Thursday Afternoon | W 10 - 20 |
| Mt. Hood | Direction - Speed |
|---|---|
| Wednesday Evening | SSW 10 - 20 |
| Wednesday Night | SW 10 - 20 |
| Thursday Morning | WSW 10 - 20 |
| Thursday Afternoon | 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.
Issued: 2:13 PM PST Wednesday, December 2, 2020
Extended Weather Synopsis for Tuesday night through Tuesday
The re-developed ridge axis slides east of our region Friday night and Saturday as moderate E flow re-develops. With warm temperatures in place, we expect light to very light rain shower activity (very high elevation snow) and slight cooling to arrive Saturday night and Sunday as a slightly stronger weakening system moves in from the west and ends the easterly flow.
Extended Snow/Freezing Levels
| Mt. Baker | Snoqualmie Pass | Mt. Hood | Easterly Flow * | ||
|---|---|---|---|---|---|
| Friday Night | Freezing Level | 10000' - 11000' | 10500' - 11500' | 11000' - 12000' | * |
| Saturday | Freezing Level | 10500' - 11500' | 11000' - 12000' | 11500' - 12500' | * |
| Saturday Night | Snow Level | 6500' - 7500' | 6500' - 7500' | 6000' - 8000' | * |
| Sunday | Snow Level | 4500' - 5500' | 4500' - 5500' | 5000' - 6000' |
| Mt. Baker | Elevation |
|---|---|
| Friday Night |
Freezing Level 10000' - 11000' (Easterly Flow *) |
| Saturday |
Freezing Level 10500' - 11500' (Easterly Flow *) |
| Saturday Night |
Snow Level 6500' - 7500' (Easterly Flow *) |
| Sunday |
Snow Level 4500' - 5500' |
| Snoqualmie Pass | Elevation |
|---|---|
| Friday Night |
Freezing Level 10500' - 11500' (Easterly Flow *) |
| Saturday |
Freezing Level 11000' - 12000' (Easterly Flow *) |
| Saturday Night |
Snow Level 6500' - 7500' (Easterly Flow *) |
| Sunday |
Snow Level 4500' - 5500' |
| Mt. Hood | Elevation |
|---|---|
| Friday Night |
Freezing Level 11000' - 12000' (Easterly Flow *) |
| Saturday |
Freezing Level 11500' - 12500' (Easterly Flow *) |
| Saturday Night |
Snow Level 6000' - 8000' (Easterly Flow *) |
| Sunday |
Snow Level 5000' - 6000' |
* 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 2, 2020
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