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 & Friday
An open trough and weakening surface low sit just W-SW of Cape Flattery on Thursday afternoon. The low will dissipate as it crosses the Olympics, but the associated upper trough will continue to bring moderate rain and snow to the mountains.
Moderate free air winds (and stronger gusts) will be out of the south today, switching to SW after 4PM when the occluded front associated with the dying low crosses the Cascades, then westerly as a secondary upper trough and stronger surface cold front swings through from the NW around 1 AM. Temperatures will drop sharply behind the cold front and most locations will change back to snow as precipitation intensities are decreasing.
Easterly flow is keeping the passes cool so far on Thursday afternoon. However, Snoqualmie should see a changeover to rain around 4PM with the passage of the occluded front with a changeover back to Snow between 1 and 4 AM on Friday. Stevens Pass may see a changeover to rain during the evening hours before changing back to snow after midnight. Mt. Baker base is now back to snow and should remain wet snow until the cold front cools things the atmosphere further.
On Thursday night, precipitation should decrease behind the cold front. In the early morning hours, a convergence zone is likely to develop in the Stevens Pass vicinity and could push as far south as Snoqualmie. Snow shower activity will be light Friday and will taper off. Temperatures will be cool.
On Friday night, skies will becoming mostly clear as high pressure builds over the region.
Weather Forecast
Olympics
| Thursday | Periods of light rain and snow. |
| Thursday Night | Light rain and snow changing to all snow after midnight. Moderate SW winds changing to westerly winds after midnight. |
| Friday | Cold in the morning with snow showers ending early; otherwise partly cloudy. |
| Friday Night | Mostly clear. |
Washington Cascades near and west of the Crest including Stevens, Snoqualmie and White Passes
| Thursday | Moderate rain and snow. Moderate easterly winds in the passes. Moderate (gusting to strong) southerly winds. |
| Thursday Night | Moderate rain and snow in the evening, changing to light to moderate snow showers after midnight, heaviest in convergence near Stevens Pass. Moderate SW winds switching to westerly after midnight. |
| Friday | Light snow showers, decreasing. Otherwise mostly cloudy skies. |
| Friday Night | Partly cloudy with ESE winds developing after midnight. |
East Slopes of the Washington Cascades
| Thursday | Light to moderate rain and snow. Moderate easterly winds in the passes. Moderate (gusting to strong) southerly winds. |
| Thursday Night | Light to moderate rain and snow in the evening, changing to light snow showers after midnight, heaviest in convergence near Stevens Pass. Moderate SW winds switching to westerly after midnight. |
| Friday | Light snow showers near the Cascade Crest, decreasing. Otherwise partly sunny skies. |
| Friday Night | Mostly clear. |
Mt. Hood
| Thursday | Moderate rain and snow. Strong S-SW winds. |
| Thursday Night | Moderate rain and snow along with strong SW winds becoming light snow showers in the early morning hours with moderate to strong W-SW winds. |
| Friday | Rapidly decreasing light snow showers in the morning and partly cloudy skies in the afternoon. Decreasing moderate westerly winds. |
| Friday Night | Clear skies with rising freezing levels and light winds. |
Issued: 2:58 PM PST Thursday, March 8, 2018
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 * | 4500' | 3500' | 3000' | ' | ' | 3500' | ' | 4500' |
| Thursday Night | Snow Level | 2000' | 2000' | 2500' | ' | ' | 3000' | ' | 3500' |
| Friday Morning | Snow Level | 2000' | 1500' | 1500' | ' | ' | 1500' | ' | 1500' |
| Friday Afternoon | Snow Level | 2500' | 2000' | 2000' | ' | ' | 3000' | ' | 3500' |
| Friday Night | Freezing Level | 2000' | 2000' | 1500' | ' | ' | 2000' | ' | 3000' |
| Hurricane Ridge | Elevation |
|---|---|
| Thursday Afternoon |
Snow Level 4500' (Easterly Flow *) |
| Thursday Night |
Snow Level 2000' |
| Friday Morning |
Snow Level 2000' |
| Friday Afternoon |
Snow Level 2500' |
| Friday Night |
Freezing Level 2000' |
| Mt. Baker | Elevation |
|---|---|
| Thursday Afternoon |
Snow Level 3500' (Easterly Flow *) |
| Thursday Night |
Snow Level 2000' |
| Friday Morning |
Snow Level 1500' |
| Friday Afternoon |
Snow Level 2000' |
| Friday Night |
Freezing Level 2000' |
| Washington Pass | Elevation |
|---|---|
| Thursday Afternoon |
Snow Level 3000' (Easterly Flow *) |
| Thursday Night |
Snow Level 2500' |
| Friday Morning |
Snow Level 1500' |
| Friday Afternoon |
Snow Level 2000' |
| Friday Night |
Freezing Level 1500' |
| Leavenworth | Elevation |
|---|---|
| Thursday Afternoon |
Snow Level ' (Easterly Flow *) |
| Thursday Night |
Snow Level ' |
| Friday Morning |
Snow Level ' |
| Friday Afternoon |
Snow Level ' |
| Friday Night |
Freezing Level ' |
| Stevens Pass | Elevation |
|---|---|
| Thursday Afternoon |
Snow Level ' (Easterly Flow *) |
| Thursday Night |
Snow Level ' |
| Friday Morning |
Snow Level ' |
| Friday Afternoon |
Snow Level ' |
| Friday Night |
Freezing Level ' |
| Snoqualmie Pass | Elevation |
|---|---|
| Thursday Afternoon |
Snow Level 3500' (Easterly Flow *) |
| Thursday Night |
Snow Level 3000' |
| Friday Morning |
Snow Level 1500' |
| Friday Afternoon |
Snow Level 3000' |
| Friday Night |
Freezing Level 2000' |
| Mt. Rainier & Crystal | Elevation |
|---|---|
| Thursday Afternoon |
Snow Level ' (Easterly Flow *) |
| Thursday Night |
Snow Level ' |
| Friday Morning |
Snow Level ' |
| Friday Afternoon |
Snow Level ' |
| Friday Night |
Freezing Level ' |
| Mt. Hood | Elevation |
|---|---|
| Thursday Afternoon |
Snow Level 4500' (Easterly Flow *) |
| Thursday Night |
Snow Level 3500' |
| Friday Morning |
Snow Level 1500' |
| Friday Afternoon |
Snow Level 3500' |
| Friday Night |
Freezing Level 3000' |
* 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
| Friday | Friday | |
|---|---|---|
| Hurricane Ridge | 0.50 - 0.75 | LT 0.10 |
| Mt Baker Ski Area | 1.50 - 2.00 | LT 0.10 |
| Washington Pass | 0 - 1.00 | LT 0.10 |
| Stevens Pass | 0 - 1.00 | LT 0.25 |
| Snoqualmie Pass | 0 - 1.50 | LT 0.25 |
| Mission Ridge | LT 0.25 | LT 0.10 |
| Crystal Mt | 0.75 - 1.00 | LT 0.10 |
| Paradise | 1.00 - 1.50 | LT 0.10 |
| White Pass | 0.75 - 1.00 | LT 0.10 |
| Mt Hood Meadows | 0.75 - 1.00 | LT 0.10 |
| Timberline | 0 - 0.75 | 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: 2:58 PM PST Thursday, March 8, 2018
Free Winds at 5000' (mph)
| Hurricane Ridge | Mt. Baker | Stevens to Snoqualmie Pass | Mt. Rainier | Mt. Hood | |
|---|---|---|---|---|---|
| Thursday Afternoon | WSW 20 - 30 | SSE 15 - 25 | S 30 - 40 | --- - | WSW 45 - 65 |
| Thursday Night | WSW 30 - 40 | SW 25 - 35 | W 30 - 40 | --- - | WSW 35 - 50 |
| Friday Morning | W 15 - 25 | WSW 10 - 20 | W 30 - 40 | --- - | WSW 35 - 50 |
| Friday Afternoon | W 5 - 15 | W 5 - 15 | W 10 - 20 | --- - | W 10 - 20 |
| Friday Night | VAR 0 - 10 | VAR 0 - 10 | VAR 0 - 10 | --- - | SW 0 - 10 |
| Hurricane Ridge | Elevation |
|---|---|
| Thursday Afternoon | WSW 20 - 30 |
| Thursday Night | WSW 30 - 40 |
| Friday Morning | W 15 - 25 |
| Friday Afternoon | W 5 - 15 |
| Friday Night | VAR 0 - 10 |
| Mt. Baker | Elevation |
|---|---|
| Thursday Afternoon | SSE 15 - 25 |
| Thursday Night | SW 25 - 35 |
| Friday Morning | WSW 10 - 20 |
| Friday Afternoon | W 5 - 15 |
| Friday Night | VAR 0 - 10 |
| Stevens and Snoqualmie Pass | Elevation |
|---|---|
| Thursday Afternoon | S 30 - 40 |
| Thursday Night | W 30 - 40 |
| Friday Morning | W 30 - 40 |
| Friday Afternoon | W 10 - 20 |
| Friday Night | VAR 0 - 10 |
| Mt. Rainier | Elevation |
|---|---|
| Thursday Afternoon | --- - |
| Thursday Night | --- - |
| Friday Morning | --- - |
| Friday Afternoon | --- - |
| Friday Night | --- - |
| Mt. Hood | Elevation |
|---|---|
| Thursday Afternoon | WSW 45 - 65 |
| Thursday Night | WSW 35 - 50 |
| Friday Morning | WSW 35 - 50 |
| Friday Afternoon | W 10 - 20 |
| Friday Night | SW 0 - 10 |
| Hurricane Ridge | Direction - Speed |
|---|---|
| Thursday Afternoon | WSW 20 - 30 |
| Thursday Night | WSW 30 - 40 |
| Friday Morning | W 15 - 25 |
| Friday Afternoon | W 5 - 15 |
| Friday Night | VAR 0 - 10 |
| Mt. Baker | Direction - Speed |
|---|---|
| Thursday Afternoon | SSE 15 - 25 |
| Thursday Night | SW 25 - 35 |
| Friday Morning | WSW 10 - 20 |
| Friday Afternoon | W 5 - 15 |
| Friday Night | VAR 0 - 10 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Thursday Afternoon | S 30 - 40 |
| Thursday Night | W 30 - 40 |
| Friday Morning | W 30 - 40 |
| Friday Afternoon | W 10 - 20 |
| Friday Night | VAR 0 - 10 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Thursday Afternoon | --- - |
| Thursday Night | --- - |
| Friday Morning | --- - |
| Friday Afternoon | --- - |
| Friday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| Thursday Afternoon | WSW 45 - 65 |
| Thursday Night | WSW 35 - 50 |
| Friday Morning | WSW 35 - 50 |
| Friday Afternoon | W 10 - 20 |
| Friday Night | SW 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 | |
|---|---|---|---|---|---|
| Thursday Afternoon | SSW 35 - 50 | SSW 45 - 65 | SW 55 - 75 | --- - | SW 65 - 85 |
| Thursday Night | WSW 30 - 40 | WSW 40 - 60 | WSW 50 - 70 | --- - | WSW 50 - 70 |
| Friday Morning | W 20 - 30 | W 25 - 35 | WNW 35 - 50 | --- - | W 30 - 40 |
| Friday Afternoon | W 10 - 20 | WNW 15 - 25 | WNW 25 - 35 | --- - | W 20 - 30 |
| Friday Night | WSW 5 - 15 | VAR 0 - 10 | W 5 - 15 | --- - | WSW 10 - 20 |
| Mt. Baker | Direction - Speed |
|---|---|
| Thursday Afternoon | SSW 35 - 50 |
| Thursday Night | WSW 30 - 40 |
| Friday Morning | W 20 - 30 |
| Friday Afternoon | W 10 - 20 |
| Friday Night | WSW 5 - 15 |
| Washington Pass | Direction - Speed |
|---|---|
| Thursday Afternoon | SSW 45 - 65 |
| Thursday Night | WSW 40 - 60 |
| Friday Morning | W 25 - 35 |
| Friday Afternoon | WNW 15 - 25 |
| Friday Night | VAR 0 - 10 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Thursday Afternoon | SW 55 - 75 |
| Thursday Night | WSW 50 - 70 |
| Friday Morning | WNW 35 - 50 |
| Friday Afternoon | WNW 25 - 35 |
| Friday Night | W 5 - 15 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Thursday Afternoon | --- - |
| Thursday Night | --- - |
| Friday Morning | --- - |
| Friday Afternoon | --- - |
| Friday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| Thursday Afternoon | SW 65 - 85 |
| Thursday Night | WSW 50 - 70 |
| Friday Morning | W 30 - 40 |
| Friday Afternoon | W 20 - 30 |
| Friday Night | 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: 2:58 PM PST Thursday, March 8, 2018
Extended Weather Synopsis for Friday night through Friday
On Saturday, the ridge builds rapidly over the Pacific NW with a ridge axis east of the Cascades. On Saturday night, there's a slight chance of showers as a very weak shortwave trough passes over the ridge. Easterly flow develops Saturday morning and continues through Monday.
On Sunday, the ridge broadens and increases in size to encompass the entire western US and most of western Canada.
On Sunday night through Monday, a deep trough and surface low starts pushing the ridge east with precipitation extending north into our near shore waters and a surface low likely off the coast of California.
Extended Weather
Olympics, Washington Cascades and Mt. Hood Area
Extended Snow/Freezing Levels
| Mt. Baker | Snoqualmie Pass | Mt. Hood | Easterly Flow * | ||
|---|---|---|---|---|---|
| Saturday | Freezing Level | 5500' - 6500' | 4000' - 6000' | 6000' - 7000' | * |
| Saturday Night | Freezing Level | 6000' - 7000' | 6000' - 7000' | 7000' - 8000' | * |
| Sunday | Freezing Level | 7000' - 8000' | 7000' - 8000' | 7500' - 8500' | * |
| Sunday Night | Freezing Level | 7500' - 8500' | 7000' - 8000' | 7500' - 8500' | * |
| Monday | Freezing Level | 7500' - 8500' | 8000' - 9000' | 8000' - 9000' | * |
| Mt. Baker | Elevation |
|---|---|
| Saturday |
Freezing Level 5500' - 6500' (Easterly Flow *) |
| Saturday Night |
Freezing Level 6000' - 7000' (Easterly Flow *) |
| Sunday |
Freezing Level 7000' - 8000' (Easterly Flow *) |
| Sunday Night |
Freezing Level 7500' - 8500' (Easterly Flow *) |
| Monday |
Freezing Level 7500' - 8500' (Easterly Flow *) |
| Snoqualmie Pass | Elevation |
|---|---|
| Saturday |
Freezing Level 4000' - 6000' (Easterly Flow *) |
| Saturday Night |
Freezing Level 6000' - 7000' (Easterly Flow *) |
| Sunday |
Freezing Level 7000' - 8000' (Easterly Flow *) |
| Sunday Night |
Freezing Level 7000' - 8000' (Easterly Flow *) |
| Monday |
Freezing Level 8000' - 9000' (Easterly Flow *) |
| Mt. Hood | Elevation |
|---|---|
| Saturday |
Freezing Level 6000' - 7000' (Easterly Flow *) |
| Saturday Night |
Freezing Level 7000' - 8000' (Easterly Flow *) |
| Sunday |
Freezing Level 7500' - 8500' (Easterly Flow *) |
| Sunday Night |
Freezing Level 7500' - 8500' (Easterly Flow *) |
| Monday |
Freezing Level 8000' - 9000' (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 Mar 8, 2018
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