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 & Friday
A surface and upper low are spinning off the Queen Charlotte Islands while an attached frontal system moves over the Pacific Northwest. A warm front is lifting over the forecast area today bringing approximately 5 F of free air warming and a N-S oriented cold front will pass late tonight bringing about 8 F of free air cooling. Easterly flow has developed as the frontal system approaches, but the easterly flow is bringing not bringing in much cooler air, likely due to solar effects. The system will bring increasing S and SE crest-level winds which will be within the moderate to strong range most of the day Wednesday, further increasing during the evening hours. Increasing light snow this morning will become moderate by the afternoon, with heavier precipitation rates on the Cascade Volcanoes which are generally favored by southerly flow.
Following the cold frontal passage Wednesday night, winds will decrease significant and snow will becoming light and sporadic. There will not be much of a post-frontal wind shift as the upper low stays offshore.
On Thursday, the cold upper low slides south and will spin 300 miles off the Washington coast by Thursday afternoon, bringing bands of light snow over the forecast area. Partly cloudy conditions are expected and the sun is beginning to gain strength, so in spite of the cool temperatures, expect some surface warming.
Thursday night, the cold upper low slides SE into the Oregon coastal waters, bringing further cooling, particularly in the Mt. Hood area.
Weather Forecast
Olympics
| Wednesday | Increasing light snow. Modest warming. Increasing moderate to strong winds. |
| Wednesday Night | Stormy during the evening hours with strong winds and light to moderate snow. Snow and wind will decrease after midnight. |
| Thursday | A chance of light snow with partly cloudy conditions otherwise. |
| Thursday Night | Periods of light snow with skies clearing at times. |
Washington Cascades near and west of the Crest including Stevens, Snoqualmie and White Passes
| Wednesday | Increasing light to moderate snow in the Cascade passes with increasing moderate to heavy snow over Cascade volcanoes. Increasing moderate to strong crest-level winds with light to moderate easterly flow in the passes. |
| Wednesday Night | Moderate snow with moderate to strong southerly winds, heaviest Cascade volcanoes, particularly Mt. Baker, and lightest Cascade passes. Light showers lingering after midnight. Moderate east flow through the passes during the evening hours. |
| Thursday | A chance of light snow with partly cloudy conditions otherwise. |
| Thursday Night | A chance of light snow with partly clear conditions otherwise. |
East Slopes of the Washington Cascades
| Wednesday | Increasing light to occasionally moderate snow with increasing moderate to strong crest-level winds. |
| Wednesday Night | Light to moderate snow with strong southerly winds. Light snow showers lingering after midnight with rapidly decreasing winds. |
| Thursday | A chance of light snow with partly cloudy conditions otherwise. |
| Thursday Night | A chance of light snow with partly clear conditions otherwise. |
Mt. Hood
| Wednesday | Increasing light to moderate snow during the morning hours becoming moderate to occasionally heavy in the afternoon with increasing moderate to strong winds. |
| Wednesday Night | Moderate to heavy snow with strong ridge-top winds during the evening hours. Rapidly decreasing winds after midnight with snow showers becoming generally light. |
| Thursday | Light to occasionally moderate bands of snow with sun breaks in between. |
| Thursday Night | Light bands of snow with clearing in between. |
Issued: 2:32 PM PST Wednesday, February 28, 2018
Snow/Freezing Level (ft)
| Hurricane Ridge | Mt. Baker | Washington Pass | Leavenworth | Stevens Pass | Snoqualmie Pass | Mt. Rainier, Crystal & White Pass | Mt. Hood | ||
|---|---|---|---|---|---|---|---|---|---|
| Wednesday Afternoon | Snow Level * | 2500' | 2000' | 1500' | ' | ' | 3000' | ' | 3000' |
| Wednesday Night | Snow Level * | 2500' | 2500' | 2000' | ' | ' | 2500' | ' | 1500' |
| Thursday Morning | Snow Level * | 2000' | 1500' | 2000' | ' | ' | 2000' | ' | 2000' |
| Thursday Afternoon | Snow Level * | 2500' | 3000' | 2500' | ' | ' | 2500' | ' | 3500' |
| Thursday Night | Snow Level * | 2000' | 2500' | 2000' | ' | ' | 2000' | ' | 1000' |
| Hurricane Ridge | Elevation |
|---|---|
| Wednesday Afternoon |
Snow Level 2500' (Easterly Flow *) |
| Wednesday Night |
Snow Level 2500' (Easterly Flow *) |
| Thursday Morning |
Snow Level 2000' (Easterly Flow *) |
| Thursday Afternoon |
Snow Level 2500' (Easterly Flow *) |
| Thursday Night |
Snow Level 2000' (Easterly Flow *) |
| Mt. Baker | Elevation |
|---|---|
| Wednesday Afternoon |
Snow Level 2000' (Easterly Flow *) |
| Wednesday Night |
Snow Level 2500' (Easterly Flow *) |
| Thursday Morning |
Snow Level 1500' (Easterly Flow *) |
| Thursday Afternoon |
Snow Level 3000' (Easterly Flow *) |
| Thursday Night |
Snow Level 2500' (Easterly Flow *) |
| Washington Pass | Elevation |
|---|---|
| Wednesday Afternoon |
Snow Level 1500' (Easterly Flow *) |
| Wednesday Night |
Snow Level 2000' (Easterly Flow *) |
| Thursday Morning |
Snow Level 2000' (Easterly Flow *) |
| Thursday Afternoon |
Snow Level 2500' (Easterly Flow *) |
| Thursday Night |
Snow Level 2000' (Easterly Flow *) |
| Leavenworth | Elevation |
|---|---|
| Wednesday Afternoon |
Snow Level ' (Easterly Flow *) |
| Wednesday Night |
Snow Level ' (Easterly Flow *) |
| Thursday Morning |
Snow Level ' (Easterly Flow *) |
| Thursday Afternoon |
Snow Level ' (Easterly Flow *) |
| Thursday Night |
Snow Level ' (Easterly Flow *) |
| Stevens Pass | Elevation |
|---|---|
| Wednesday Afternoon |
Snow Level ' (Easterly Flow *) |
| Wednesday Night |
Snow Level ' (Easterly Flow *) |
| Thursday Morning |
Snow Level ' (Easterly Flow *) |
| Thursday Afternoon |
Snow Level ' (Easterly Flow *) |
| Thursday Night |
Snow Level ' (Easterly Flow *) |
| Snoqualmie Pass | Elevation |
|---|---|
| Wednesday Afternoon |
Snow Level 3000' (Easterly Flow *) |
| Wednesday Night |
Snow Level 2500' (Easterly Flow *) |
| Thursday Morning |
Snow Level 2000' (Easterly Flow *) |
| Thursday Afternoon |
Snow Level 2500' (Easterly Flow *) |
| Thursday Night |
Snow Level 2000' (Easterly Flow *) |
| Mt. Rainier & Crystal | Elevation |
|---|---|
| Wednesday Afternoon |
Snow Level ' (Easterly Flow *) |
| Wednesday Night |
Snow Level ' (Easterly Flow *) |
| Thursday Morning |
Snow Level ' (Easterly Flow *) |
| Thursday Afternoon |
Snow Level ' (Easterly Flow *) |
| Thursday Night |
Snow Level ' (Easterly Flow *) |
| Mt. Hood | Elevation |
|---|---|
| Wednesday Afternoon |
Snow Level 3000' (Easterly Flow *) |
| Wednesday Night |
Snow Level 1500' (Easterly Flow *) |
| Thursday Morning |
Snow Level 2000' (Easterly Flow *) |
| Thursday Afternoon |
Snow Level 3500' (Easterly Flow *) |
| Thursday Night |
Snow Level 1000' (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
| Friday | Friday | |
|---|---|---|
| Hurricane Ridge | 0 - 0.50 | LT 0.25 |
| Mt Baker Ski Area | 0 - 1.50 | 0.25 - 0.50 |
| Washington Pass | 0.25 - 0.50 | LT 0.25 |
| Stevens Pass | 0.25 - 0.50 | LT 0.25 |
| Snoqualmie Pass | 0 - 0.50 | LT 0.25 |
| Mission Ridge | 0.50 - 0.75 | LT 0.25 |
| Crystal Mt | 0 - 1.00 | LT 0.25 |
| Paradise | 1.00 - 1.50 | 0.25 - 0.50 |
| White Pass | 0.25 - 0.50 | LT 0.25 |
| Mt Hood Meadows | 1.00 - 1.50 | 0.25 - 0.50 |
| Timberline | 1.00 - 1.50 | 0.25 - 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: 2:32 PM PST Wednesday, February 28, 2018
Free Winds at 5000' (mph)
| Hurricane Ridge | Mt. Baker | Stevens to Snoqualmie Pass | Mt. Rainier | Mt. Hood | |
|---|---|---|---|---|---|
| Wednesday Afternoon | S 30 - 40 | SE 30 - 40 | SE 25 - 35 | --- - | S 30 - 40 |
| Wednesday Night | SSE 20 - 30 | ESE 30 - 40 | ESE 30 - 40 | --- - | S 40 - 60 |
| Thursday Morning | VAR 0 - 10 | S 0 - 10 | SSE 0 - 10 | --- - | SW 10 - 20 |
| Thursday Afternoon | E 5 - 15 | VAR 0 - 10 | ESE 0 - 10 | --- - | ESE 5 - 15 |
| Thursday Night | E 5 - 15 | E 5 - 15 | VAR 0 - 10 | --- - | WSW 15 - 25 |
| Hurricane Ridge | Elevation |
|---|---|
| Wednesday Afternoon | S 30 - 40 |
| Wednesday Night | SSE 20 - 30 |
| Thursday Morning | VAR 0 - 10 |
| Thursday Afternoon | E 5 - 15 |
| Thursday Night | E 5 - 15 |
| Mt. Baker | Elevation |
|---|---|
| Wednesday Afternoon | SE 30 - 40 |
| Wednesday Night | ESE 30 - 40 |
| Thursday Morning | S 0 - 10 |
| Thursday Afternoon | VAR 0 - 10 |
| Thursday Night | E 5 - 15 |
| Stevens and Snoqualmie Pass | Elevation |
|---|---|
| Wednesday Afternoon | SE 25 - 35 |
| Wednesday Night | ESE 30 - 40 |
| Thursday Morning | SSE 0 - 10 |
| Thursday Afternoon | ESE 0 - 10 |
| Thursday Night | VAR 0 - 10 |
| Mt. Rainier | Elevation |
|---|---|
| Wednesday Afternoon | --- - |
| Wednesday Night | --- - |
| Thursday Morning | --- - |
| Thursday Afternoon | --- - |
| Thursday Night | --- - |
| Mt. Hood | Elevation |
|---|---|
| Wednesday Afternoon | S 30 - 40 |
| Wednesday Night | S 40 - 60 |
| Thursday Morning | SW 10 - 20 |
| Thursday Afternoon | ESE 5 - 15 |
| Thursday Night | WSW 15 - 25 |
| Hurricane Ridge | Direction - Speed |
|---|---|
| Wednesday Afternoon | S 30 - 40 |
| Wednesday Night | SSE 20 - 30 |
| Thursday Morning | VAR 0 - 10 |
| Thursday Afternoon | E 5 - 15 |
| Thursday Night | E 5 - 15 |
| Mt. Baker | Direction - Speed |
|---|---|
| Wednesday Afternoon | SE 30 - 40 |
| Wednesday Night | ESE 30 - 40 |
| Thursday Morning | S 0 - 10 |
| Thursday Afternoon | VAR 0 - 10 |
| Thursday Night | E 5 - 15 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Wednesday Afternoon | SE 25 - 35 |
| Wednesday Night | ESE 30 - 40 |
| Thursday Morning | SSE 0 - 10 |
| Thursday Afternoon | ESE 0 - 10 |
| Thursday Night | VAR 0 - 10 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Wednesday Afternoon | --- - |
| Wednesday Night | --- - |
| Thursday Morning | --- - |
| Thursday Afternoon | --- - |
| Thursday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| Wednesday Afternoon | S 30 - 40 |
| Wednesday Night | S 40 - 60 |
| Thursday Morning | SW 10 - 20 |
| Thursday Afternoon | ESE 5 - 15 |
| Thursday Night | WSW 15 - 25 |
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 Afternoon | SSW 40 - 60 | SW 25 - 35 | SW 35 - 50 | --- - | SW 35 - 50 |
| Wednesday Night | S 40 - 60 | S 35 - 50 | SSE 45 - 65 | --- - | SW 55 - 75 |
| Thursday Morning | S 30 - 40 | SSE 25 - 35 | S 30 - 40 | --- - | SSW 45 - 65 |
| Thursday Afternoon | SE 20 - 30 | SE 10 - 20 | SSE 10 - 20 | --- - | SSW 25 - 35 |
| Thursday Night | E 0 - 10 | ESE 0 - 10 | SSE 0 - 10 | --- - | WSW 20 - 30 |
| Mt. Baker | Direction - Speed |
|---|---|
| Wednesday Afternoon | SSW 40 - 60 |
| Wednesday Night | S 40 - 60 |
| Thursday Morning | S 30 - 40 |
| Thursday Afternoon | SE 20 - 30 |
| Thursday Night | E 0 - 10 |
| Washington Pass | Direction - Speed |
|---|---|
| Wednesday Afternoon | SW 25 - 35 |
| Wednesday Night | S 35 - 50 |
| Thursday Morning | SSE 25 - 35 |
| Thursday Afternoon | SE 10 - 20 |
| Thursday Night | ESE 0 - 10 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Wednesday Afternoon | SW 35 - 50 |
| Wednesday Night | SSE 45 - 65 |
| Thursday Morning | S 30 - 40 |
| Thursday Afternoon | SSE 10 - 20 |
| Thursday Night | SSE 0 - 10 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Wednesday Afternoon | --- - |
| Wednesday Night | --- - |
| Thursday Morning | --- - |
| Thursday Afternoon | --- - |
| Thursday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| Wednesday Afternoon | SW 35 - 50 |
| Wednesday Night | SW 55 - 75 |
| Thursday Morning | SSW 45 - 65 |
| Thursday Afternoon | SSW 25 - 35 |
| Thursday Night | WSW 20 - 30 |
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: 2:32 PM PST Wednesday, February 28, 2018
Extended Weather Synopsis for Friday night through Friday
On Friday, a broad upper low will sit off the coast along with several small-scale surface low features bringing a chance of showers on Friday as they rotates around the upper low. On Friday night, the primary upper low fills and the broad trough with sit over the NW United Sates through Saturday, sending most of the moisture south into California, but it will spin isolated bands of snow showers northward.
On Saturday, the cool air in place brings a chance of convective snow showers.
On Saturday night the trough moves eastward and shower activity on the back edge of the trough increases over our region.
A weak shortwave feature may develop and swing down the back side of the trough into the forecast area, bringing some light snow on Sunday.
Extended Weather
Olympics, Washington Cascades and Mt. Hood Area
Extended Snow/Freezing Levels
| Mt. Baker | Snoqualmie Pass | Mt. Hood | Easterly Flow * | ||
|---|---|---|---|---|---|
| Friday | Snow Level | 0' - 2000' | 0' - 2000' | 0' - 2000' | |
| Friday Night | Snow Level | 0' - 2000' | 0' - 2000' | 0' - 2000' | |
| Saturday | Snow Level | 1000' - 3000' | 1000' - 3000' | 1000' - 3000' | |
| Saturday Night | Snow Level | 0' - 1000' | 0' - 1000' | 0' - 1000' | |
| Sunday | Snow Level | 500' - 2500' | 1000' - 3000' | 1000' - 3000' |
| Mt. Baker | Elevation |
|---|---|
| Friday |
Snow Level 0' - 2000' |
| Friday Night |
Snow Level 0' - 2000' |
| Saturday |
Snow Level 1000' - 3000' |
| Saturday Night |
Snow Level 0' - 1000' |
| Sunday |
Snow Level 500' - 2500' |
| Snoqualmie Pass | Elevation |
|---|---|
| Friday |
Snow Level 0' - 2000' |
| Friday Night |
Snow Level 0' - 2000' |
| Saturday |
Snow Level 1000' - 3000' |
| Saturday Night |
Snow Level 0' - 1000' |
| Sunday |
Snow Level 1000' - 3000' |
| Mt. Hood | Elevation |
|---|---|
| Friday |
Snow Level 0' - 2000' |
| Friday Night |
Snow Level 0' - 2000' |
| Saturday |
Snow Level 1000' - 3000' |
| Saturday Night |
Snow Level 0' - 1000' |
| Sunday |
Snow Level 1000' - 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.
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 28, 2018
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