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 night through Friday
The leading edge of a cool and rotating upper and mid-level trough will continue to move a band of snow through the Cascades and Olympics Thursday evening. The initial rain/snow band passes most locations by midnight and a cool W-SW flow will bring moist, unstable air and continue mountain-induced rain/snow while bringing moderate winds across the region. Pass-level flow will switch to westerly during the late evening hours as the frontal feature crosses the region and this is likely to switch Snoqualmie Pass from initial snowfall to a rain/snow mix with all snow continuing at the higher passes.
The moist, unstable flow will continue flow will continue across the region Friday as the trough slides SE and will be squarely over the Pacific Northwest by Friday afternoon. Light to moderate snow showers should continue in most mountain locations (possibly mixing with rain at the lower passes, like Snoqualmie). Winds should become light during the day.
Friday night, the trough moves east and a shortwave ridge builds over the coastal waters, bringing a cool night to the mountains and some clearing.
On Saturday, most locations will see fair weather as the ridge slides onshore with a very weak front on its heals keeping clouds and a chance of a rain or snow shower possible over the Olympics.
Weather Forecast
Hurricane Ridge
| Thursday Night | Light rain and snow decreasing during the evening hours and then rain and snow showers increasing after midnight. |
| Friday | Light to moderate snow showers. |
Mt. Baker
| Thursday Night | Moderate rain and snow becoming moderate showers after midnight. |
| Friday | Moderate snow becoming light in the afternoon. |
Stevens and Snoqualmie Pass
| Thursday Night | Light to moderate rain and snow decreasing before midnight and increasing after midnight. Rain mixing with snow at Snoqualmie Pass, but should stay all snow at Stevens Pass. |
| Friday | Moderate rain and snow. Expect significant accumulations at Stevens Pass with a rain/snow mix at Snoqualmie Pass. |
Mt. Rainier and Crystal
| Thursday Night | Moderate snow with a WSW flow. |
| Friday | Moderate snow with a WSW flow. |
Washington Pass and Leavenworth
| Thursday Night | Light to moderate snow becoming light after midnight. |
| Friday | Light snow with periods of moderate intensity. |
Mt. Hood
| Thursday Night | Moderate rain and snow with a WSW flow. |
| Friday | Moderate rain and snow with a WSW flow. |
Issued: 2:47 PM PST Thursday, November 22, 2018
Snow/Freezing Level (ft)
| Hurricane Ridge | Mt. Baker | Washington Pass | Leavenworth | Stevens Pass | Snoqualmie Pass | Mt. Rainier, Crystal & White Pass | Mt. Hood | ||
|---|---|---|---|---|---|---|---|---|---|
| Thursday Evening | Snow Level * | 3500' | 3500' | 3000' | 3500' | 3000' | 3500' | 3500' | 4000' |
| Thursday Night | Snow Level | 3000' | 3000' | 3000' | 3000' | 3000' | 3000' | 3500' | 4000' |
| Friday Morning | Snow Level | 2500' | 2500' | 3000' | 3000' | 3000' | 3000' | 3500' | 4000' |
| Friday Afternoon | Snow Level | 3000' | 2500' | 2500' | 3000' | 3000' | 3000' | 3000' | 4000' |
| Friday Evening | Snow Level | 2500' | 2000' | 2000' | 2500' | 2500' | 2500' | 2500' | 3000' |
| Friday Night | Snow Level | 2500' | 2500' | 2000' | 2000' | 2000' | 2000' | 2000' | 2500' |
| Saturday Morning | Snow Level | 3000' | 2000' | 1500' | 2500' | 2000' | 2500' | 2500' | 2500' |
| Saturday Afternoon | Freezing Level | 4500' | 3500' | 3500' | 4000' | 3500' | 4000' | 4000' | 4500' |
| Hurricane Ridge | Elevation |
|---|---|
| Thursday Evening |
Snow Level 3500' (Easterly Flow *) |
| Thursday Night |
Snow Level 3000' |
| Friday Morning |
Snow Level 2500' |
| Friday Afternoon |
Snow Level 3000' |
| Friday Evening |
Snow Level 2500' |
| Friday Night |
Snow Level 2500' |
| Saturday Morning |
Snow Level 3000' |
| Saturday Afternoon |
Freezing Level 4500' |
| Mt. Baker | Elevation |
|---|---|
| Thursday Evening |
Snow Level 3500' (Easterly Flow *) |
| Thursday Night |
Snow Level 3000' |
| Friday Morning |
Snow Level 2500' |
| Friday Afternoon |
Snow Level 2500' |
| Friday Evening |
Snow Level 2000' |
| Friday Night |
Snow Level 2500' |
| Saturday Morning |
Snow Level 2000' |
| Saturday Afternoon |
Freezing Level 3500' |
| Washington Pass | Elevation |
|---|---|
| Thursday Evening |
Snow Level 3000' (Easterly Flow *) |
| Thursday Night |
Snow Level 3000' |
| Friday Morning |
Snow Level 3000' |
| Friday Afternoon |
Snow Level 2500' |
| Friday Evening |
Snow Level 2000' |
| Friday Night |
Snow Level 2000' |
| Saturday Morning |
Snow Level 1500' |
| Saturday Afternoon |
Freezing Level 3500' |
| Leavenworth | Elevation |
|---|---|
| Thursday Evening |
Snow Level 3500' (Easterly Flow *) |
| Thursday Night |
Snow Level 3000' |
| Friday Morning |
Snow Level 3000' |
| Friday Afternoon |
Snow Level 3000' |
| Friday Evening |
Snow Level 2500' |
| Friday Night |
Snow Level 2000' |
| Saturday Morning |
Snow Level 2500' |
| Saturday Afternoon |
Freezing Level 4000' |
| Stevens Pass | Elevation |
|---|---|
| Thursday Evening |
Snow Level 3000' (Easterly Flow *) |
| Thursday Night |
Snow Level 3000' |
| Friday Morning |
Snow Level 3000' |
| Friday Afternoon |
Snow Level 3000' |
| Friday Evening |
Snow Level 2500' |
| Friday Night |
Snow Level 2000' |
| Saturday Morning |
Snow Level 2000' |
| Saturday Afternoon |
Freezing Level 3500' |
| Snoqualmie Pass | Elevation |
|---|---|
| Thursday Evening |
Snow Level 3500' (Easterly Flow *) |
| Thursday Night |
Snow Level 3000' |
| Friday Morning |
Snow Level 3000' |
| Friday Afternoon |
Snow Level 3000' |
| Friday Evening |
Snow Level 2500' |
| Friday Night |
Snow Level 2000' |
| Saturday Morning |
Snow Level 2500' |
| Saturday Afternoon |
Freezing Level 4000' |
| Mt. Rainier & Crystal | Elevation |
|---|---|
| Thursday Evening |
Snow Level 3500' (Easterly Flow *) |
| Thursday Night |
Snow Level 3500' |
| Friday Morning |
Snow Level 3500' |
| Friday Afternoon |
Snow Level 3000' |
| Friday Evening |
Snow Level 2500' |
| Friday Night |
Snow Level 2000' |
| Saturday Morning |
Snow Level 2500' |
| Saturday Afternoon |
Freezing Level 4000' |
| Mt. Hood | Elevation |
|---|---|
| Thursday Evening |
Snow Level 4000' (Easterly Flow *) |
| Thursday Night |
Snow Level 4000' |
| Friday Morning |
Snow Level 4000' |
| Friday Afternoon |
Snow Level 4000' |
| Friday Evening |
Snow Level 3000' |
| Friday Night |
Snow Level 2500' |
| Saturday Morning |
Snow Level 2500' |
| Saturday Afternoon |
Freezing Level 4500' |
* 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
| Thursday Night | Friday | Friday Night | Friday | |
|---|---|---|---|---|
| 4 pm - 4 am | 4 am - 4 pm | 4 pm - 4 am | 4 am - 4 pm | |
| Hurricane Ridge | LT 0.25 | 0.25 - 0.50 | LT 0.10 | 0 |
| Mt Baker Ski Area | 1.00 | 0.75 | LT 0.25 | 0 |
| Washington Pass | 0.25 - 0.50 | 0.25 | LT 0.25 | 0 |
| Stevens Pass | 0.50 - 0.75 | 0.50 - 0.75 | 0.25 - 0.50 | LT 0.10 |
| Snoqualmie Pass | 0.50 - 0.75 | 0.75 | 0.25 - 0.50 | 0 |
| Leavenworth | LT 0.25 | LT 0.25 | LT 0.25 | 0 |
| Mission Ridge | 0.25 - 0.50 | 0.25 | LT 0.10 | 0 |
| Crystal Mt | 0.25 - 0.50 | 0.25 - 0.50 | LT 0.25 | 0 |
| Paradise | 1.00 - 1.50 | 1.00 | 0.25 - 0.50 | LT 0.10 |
| White Pass | 0.50 - 0.75 | 0.75 | 0.25 | 0 |
| Mt Hood Meadows | 0.75 -1.00 | 0.75 -1.00 | 0.50 - 0.75 | 0 |
| Timberline | 0.75 -1.00 | 0.75 -1.00 | 0.75 | 0 |
| Hurricane Ridge | Precipitation Forecast |
|---|---|
| Thursday Night | LT 0.25 |
| Friday | 0.25 - 0.50 |
| Friday Night | LT 0.10 |
| Friday | 0 |
| Mt Baker Ski Area | Precipitation Forecast |
|---|---|
| Thursday Night | 1.00 |
| Friday | 0.75 |
| Friday Night | LT 0.25 |
| Friday | 0 |
| Washington Pass | Precipitation Forecast |
|---|---|
| Thursday Night | 0.25 - 0.50 |
| Friday | 0.25 |
| Friday Night | LT 0.25 |
| Friday | 0 |
| Stevens Pass | Precipitation Forecast |
|---|---|
| Thursday Night | 0.50 - 0.75 |
| Friday | 0.50 - 0.75 |
| Friday Night | 0.25 - 0.50 |
| Friday | LT 0.10 |
| Snoqualmie Pass | Precipitation Forecast |
|---|---|
| Thursday Night | 0.50 - 0.75 |
| Friday | 0.75 |
| Friday Night | 0.25 - 0.50 |
| Friday | 0 |
| Leavenworth | Precipitation Forecast |
|---|---|
| Thursday Night | LT 0.25 |
| Friday | LT 0.25 |
| Friday Night | LT 0.25 |
| Friday | 0 |
| Mission Ridge | Precipitation Forecast |
|---|---|
| Thursday Night | 0.25 - 0.50 |
| Friday | 0.25 |
| Friday Night | LT 0.10 |
| Friday | 0 |
| Crystal Mt | Precipitation Forecast |
|---|---|
| Thursday Night | 0.25 - 0.50 |
| Friday | 0.25 - 0.50 |
| Friday Night | LT 0.25 |
| Friday | 0 |
| Paradise | Precipitation Forecast |
|---|---|
| Thursday Night | 1.00 - 1.50 |
| Friday | 1.00 |
| Friday Night | 0.25 - 0.50 |
| Friday | LT 0.10 |
| White Pass | Precipitation Forecast |
|---|---|
| Thursday Night | 0.50 - 0.75 |
| Friday | 0.75 |
| Friday Night | 0.25 |
| Friday | 0 |
| Mt Hood Meadows | Precipitation Forecast |
|---|---|
| Thursday Night | 0.75 -1.00 |
| Friday | 0.75 -1.00 |
| Friday Night | 0.50 - 0.75 |
| Friday | 0 |
| Timberline | Precipitation Forecast |
|---|---|
| Thursday Night | 0.75 -1.00 |
| Friday | 0.75 -1.00 |
| Friday Night | 0.75 |
| Friday | 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: 2:47 PM PST Thursday, November 22, 2018
Free Winds at 5000' (mph)
| Hurricane Ridge | Mt. Baker | Stevens to Snoqualmie Pass | Mt. Rainier | Mt. Hood | |
|---|---|---|---|---|---|
| Thursday Evening | SW 25 - 35 | SW 20 - 30 | WSW 25 - 35 | WSW 25 - 35 | WSW 35 - 50 |
| Thursday Night | WSW 35 - 50 | SSW 25 - 35 | WSW 35 - 50 | SW 20 - 30 | WSW 35 - 50 |
| Friday Morning | W 20 - 30 | SSW 15 - 25 | SW 20 - 30 | WSW 15 - 25 | WSW 20 - 30 |
| Friday Afternoon | W 15 - 25 | WSW 5 - 15 | WSW 25 - 35 | W 20 - 30 | W 25 - 35 |
| Hurricane Ridge | Elevation |
|---|---|
| Thursday Evening | SW 25 - 35 |
| Thursday Night | WSW 35 - 50 |
| Friday Morning | W 20 - 30 |
| Friday Afternoon | W 15 - 25 |
| Mt. Baker | Elevation |
|---|---|
| Thursday Evening | SW 20 - 30 |
| Thursday Night | SSW 25 - 35 |
| Friday Morning | SSW 15 - 25 |
| Friday Afternoon | WSW 5 - 15 |
| Stevens and Snoqualmie Pass | Elevation |
|---|---|
| Thursday Evening | WSW 25 - 35 |
| Thursday Night | WSW 35 - 50 |
| Friday Morning | SW 20 - 30 |
| Friday Afternoon | WSW 25 - 35 |
| Mt. Rainier | Elevation |
|---|---|
| Thursday Evening | WSW 25 - 35 |
| Thursday Night | SW 20 - 30 |
| Friday Morning | WSW 15 - 25 |
| Friday Afternoon | W 20 - 30 |
| Mt. Hood | Elevation |
|---|---|
| Thursday Evening | WSW 35 - 50 |
| Thursday Night | WSW 35 - 50 |
| Friday Morning | WSW 20 - 30 |
| Friday Afternoon | W 25 - 35 |
| Hurricane Ridge | Direction - Speed |
|---|---|
| Thursday Evening | SW 25 - 35 |
| Thursday Night | WSW 35 - 50 |
| Friday Morning | W 20 - 30 |
| Friday Afternoon | W 15 - 25 |
| Mt. Baker | Direction - Speed |
|---|---|
| Thursday Evening | SW 20 - 30 |
| Thursday Night | SSW 25 - 35 |
| Friday Morning | SSW 15 - 25 |
| Friday Afternoon | WSW 5 - 15 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Thursday Evening | WSW 25 - 35 |
| Thursday Night | WSW 35 - 50 |
| Friday Morning | SW 20 - 30 |
| Friday Afternoon | WSW 25 - 35 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Thursday Evening | WSW 25 - 35 |
| Thursday Night | SW 20 - 30 |
| Friday Morning | WSW 15 - 25 |
| Friday Afternoon | W 20 - 30 |
| Mt. Hood | Direction - Speed |
|---|---|
| Thursday Evening | WSW 35 - 50 |
| Thursday Night | WSW 35 - 50 |
| Friday Morning | WSW 20 - 30 |
| Friday Afternoon | W 25 - 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 Evening | W 30 - 45 | S 40 - 60 | WSW 30 - 45 | W 35 - 50 | WSW 40 - 60 |
| Thursday Night | WSW 35 - 50 | WSW 35 - 50 | WSW 35 - 50 | WSW 40 - 60 | WSW 45 - 65 |
| Friday Morning | WSW 25 - 35 | SW 20 - 30 | WSW 35 - 50 | WSW 35 - 50 | WSW 35 - 50 |
| Friday Afternoon | WNW 20 - 30 | W 15 - 25 | WNW 25 - 35 | NW 30 - 45 | W 40 - 60 |
| Mt. Baker | Direction - Speed |
|---|---|
| Thursday Evening | W 30 - 45 |
| Thursday Night | WSW 35 - 50 |
| Friday Morning | WSW 25 - 35 |
| Friday Afternoon | WNW 20 - 30 |
| Washington Pass | Direction - Speed |
|---|---|
| Thursday Evening | S 40 - 60 |
| Thursday Night | WSW 35 - 50 |
| Friday Morning | SW 20 - 30 |
| Friday Afternoon | W 15 - 25 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Thursday Evening | WSW 30 - 45 |
| Thursday Night | WSW 35 - 50 |
| Friday Morning | WSW 35 - 50 |
| Friday Afternoon | WNW 25 - 35 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Thursday Evening | W 35 - 50 |
| Thursday Night | WSW 40 - 60 |
| Friday Morning | WSW 35 - 50 |
| Friday Afternoon | NW 30 - 45 |
| Mt. Hood | Direction - Speed |
|---|---|
| Thursday Evening | WSW 40 - 60 |
| Thursday Night | WSW 45 - 65 |
| Friday Morning | WSW 35 - 50 |
| Friday Afternoon | W 40 - 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.
Issued: 2:47 PM PST Thursday, November 22, 2018
Extended Weather Synopsis for Friday night through Friday
Saturday night and Sunday, the weak ridge generally holds over the forecast region and keeps the weak approaching frontal system offshore, bringing mostly fair weather to our region.
On Sunday into Sunday night, a pressure gradient across the Cascades drives an increasing easterly wind through the passes as a stronger system approaches the near shore waters and brings a warming trend.
On Monday, the frontal system arrives along the coast, spreading increasingly heavy precipitation, mostly rain with snow at the higher elevations.
Extended Snow/Freezing Levels
| Mt. Baker | Snoqualmie Pass | Mt. Hood | Easterly Flow * | ||
|---|---|---|---|---|---|
| Saturday Night | Snow Level | 2500' - 3500' | 3000' - 4000' | 3500' - 4500' | |
| Sunday | Snow Level | 3000' - 4000' | 3500' - 4500' | 6500' - 7500' | * |
| Sunday Night | Snow Level | 5500' - 6500' | 4000' - 5000' | 7000' - 8000' | * |
| Monday | Snow Level | 6500' - 7500' | 6500' - 7500' | 7500' - 8500' | * |
| Mt. Baker | Elevation |
|---|---|
| Saturday Night |
Snow Level 2500' - 3500' |
| Sunday |
Snow Level 3000' - 4000' (Easterly Flow *) |
| Sunday Night |
Snow Level 5500' - 6500' (Easterly Flow *) |
| Monday |
Snow Level 6500' - 7500' (Easterly Flow *) |
| Snoqualmie Pass | Elevation |
|---|---|
| Saturday Night |
Snow Level 3000' - 4000' |
| Sunday |
Snow Level 3500' - 4500' (Easterly Flow *) |
| Sunday Night |
Snow Level 4000' - 5000' (Easterly Flow *) |
| Monday |
Snow Level 6500' - 7500' (Easterly Flow *) |
| Mt. Hood | Elevation |
|---|---|
| Saturday Night |
Snow Level 3500' - 4500' |
| Sunday |
Snow Level 6500' - 7500' (Easterly Flow *) |
| Sunday Night |
Snow Level 7000' - 8000' (Easterly Flow *) |
| Monday |
Snow Level 7500' - 8500' (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 Apr 26, 2018
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