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 & Thursday
Afternoon update: Friday's frontal system has slowed and will mostly impact the Olympics and North Cascades during the daylight hours. Day 2 precipitation amounts have been adjusted as well.
A relatively weak frontal system will push through the area today in westerly flow aloft. Generally light precipitation will accompany this frontal system along with moderate snow levels. Freezing levels at Forks and Spokane WA were 4900 and 4400 feet at 4 am this morning. Slight cooling, increasing precipitation and lowering cloud bases are expected during the day.
Flat upper level ridging in continued westerly flow aloft should build over eastern Washington Thursday night as another Pacific frontal system slowly sags south and approaches our area. Partial clearing for the south Washington Cascades down to Mt. Hood is likely while light precipitation should continue for the Olympics and Mt. Baker area overnight.
There are forecast model disagreements on timing, but the front should slowly sag south across the Washington Cascades on Friday. When it does move across the area, it should pack more of a punch than Thursday's system and at slightly cooler snow levels. More moderate precipitation will begin for the north Washington Cascades Friday afternoon but hold off for the south Washington Cascades until Friday evening. This system will largely miss Mt. Hood.
Weather Forecast
Olympics
| Thursday |
Light rain and snow becoming light showers in the afternoon. Lowering clouds. |
| Thursday Night |
Light rain and snow showers becoming scattered showers after midnight. |
| Friday |
Light rain and snow becoming light to occasionally moderate by late morning. |
| Friday Night |
Light to occasionally moderate rain and snow becoming light showers overnight. |
Washington Cascades near and west of the crest including Stevens, Snoqualmie, and White Passes
| Thursday |
Light rain and snow becoming light showers in the afternoon. Lowering clouds. |
| Thursday Night |
Light rain and snow showers becoming scattered showers after midnight. Partial clearing south and central Washington Cascades. |
| Friday Morning |
Light rain and snow north Cascades. Partly to mostly cloudy central and south Cascades. |
| Friday Night |
Light to moderate rain and snow becoming light showers overnight. |
| Friday Afternoon |
Light to occasionally moderate rain and snow north Cascades. Light rain and snow central Cascades. Mostly cloudy south Cascades. |
East slopes of the Washington Cascades
| Thursday |
Periods of light rain and snow becoming light scattered showers in the afternoon. Lowering clouds. |
| Thursday Night |
Partly to mostly cloudy with scattered rain and snow showers mainly near the Cascade crest. |
| Friday Morning |
Light rain and snow developing northeast Cascades. Partly cloudy central-east and southeast Cascades. |
| Friday Night |
Light rain and snow becoming mostly cloudy with mostly cloudy with scattered light showers overnight. |
| Friday Afternoon |
Light to occasionally moderate rain and snow northeast Cascades. Light rain and snow developing central-east Cascades. Partly to mostly cloudy southeast Cascades. |
Mt. Hood Area
| Thursday |
Light rain and snow developing in the morning and becoming light showers in the afternoon. Lowering clouds. |
| Thursday Night |
Light rain and snow showers becoming mostly cloudy with scattered showers after midnight. |
| Friday |
Partly to mostly cloudy. |
| Friday Night |
Mostly cloudy with a chance of light rain and snow showers after midnight. |
Issued: 2:49 PM PST Thursday, November 30, 2017
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 | 4000' | 3000' | 3000' | ' | ' | 3500' | ' | 4500' |
| Thursday Night | Snow Level | 3500' | 2500' | 2500' | ' | ' | 3000' | ' | 4500' |
| Friday Morning | Snow Level * | 3500' | 2500' | 2500' | ' | ' | 3000' | ' | 4000' |
| Friday Afternoon | Snow Level | 3500' | 2500' | 2500' | ' | ' | 3000' | ' | 4500' |
| Friday Night | Snow Level | 3000' | 2500' | 2500' | ' | ' | 3000' | ' | 4000' |
| Hurricane Ridge | Elevation |
|---|---|
| Thursday Afternoon |
Snow Level 4000' |
| Thursday Night |
Snow Level 3500' |
| Friday Morning |
Snow Level 3500' (Easterly Flow *) |
| Friday Afternoon |
Snow Level 3500' |
| Friday Night |
Snow Level 3000' |
| Mt. Baker | Elevation |
|---|---|
| Thursday Afternoon |
Snow Level 3000' |
| Thursday Night |
Snow Level 2500' |
| Friday Morning |
Snow Level 2500' (Easterly Flow *) |
| Friday Afternoon |
Snow Level 2500' |
| Friday Night |
Snow Level 2500' |
| Washington Pass | Elevation |
|---|---|
| Thursday Afternoon |
Snow Level 3000' |
| Thursday Night |
Snow Level 2500' |
| Friday Morning |
Snow Level 2500' (Easterly Flow *) |
| Friday Afternoon |
Snow Level 2500' |
| Friday Night |
Snow Level 2500' |
| Leavenworth | Elevation |
|---|---|
| Thursday Afternoon |
Snow Level ' |
| Thursday Night |
Snow Level ' |
| Friday Morning |
Snow Level ' (Easterly Flow *) |
| Friday Afternoon |
Snow Level ' |
| Friday Night |
Snow Level ' |
| Stevens Pass | Elevation |
|---|---|
| Thursday Afternoon |
Snow Level ' |
| Thursday Night |
Snow Level ' |
| Friday Morning |
Snow Level ' (Easterly Flow *) |
| Friday Afternoon |
Snow Level ' |
| Friday Night |
Snow Level ' |
| Snoqualmie Pass | Elevation |
|---|---|
| Thursday Afternoon |
Snow Level 3500' |
| Thursday Night |
Snow Level 3000' |
| Friday Morning |
Snow Level 3000' (Easterly Flow *) |
| Friday Afternoon |
Snow Level 3000' |
| Friday Night |
Snow Level 3000' |
| Mt. Rainier & Crystal | Elevation |
|---|---|
| Thursday Afternoon |
Snow Level ' |
| Thursday Night |
Snow Level ' |
| Friday Morning |
Snow Level ' (Easterly Flow *) |
| Friday Afternoon |
Snow Level ' |
| Friday Night |
Snow Level ' |
| Mt. Hood | Elevation |
|---|---|
| Thursday Afternoon |
Snow Level 4500' |
| Thursday Night |
Snow Level 4500' |
| Friday Morning |
Snow Level 4000' (Easterly Flow *) |
| Friday Afternoon |
Snow Level 4500' |
| Friday Night |
Snow Level 4000' |
* 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 | Thursday | |
|---|---|---|
| Hurricane Ridge | LT 0.25 | 0 - 0.75 |
| Mt Baker Ski Area | 0 - 0.50 | 0 - 1.00 |
| Washington Pass | LT 0.25 | 0 - 0.75 |
| Stevens Pass | LT 0.25 | 0 - 0.75 |
| Snoqualmie Pass | 0 - 0.50 | 0 - 0.75 |
| Mission Ridge | LT 0.10 | LT 0.10 |
| Crystal Mt | LT 0.25 | LT 0.25 |
| Paradise | 0 - 0.50 | 0 - 0.50 |
| White Pass | LT 0.25 | LT 0.25 |
| Mt Hood Meadows | 0.25 - 0.50 | LT 0.10 |
| Timberline | 0 - 0.50 | LT 0.10 |
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: 2:49 PM PST Thursday, November 30, 2017
Free Winds at 5000' (mph)
| Hurricane Ridge | Mt. Baker | Stevens to Snoqualmie Pass | Mt. Rainier | Mt. Hood | |
|---|---|---|---|---|---|
| Thursday Afternoon | SW 5 - 15 | SW 10 - 20 | SW 10 - 20 | --- - | SW 10 - 20 |
| Thursday Night | SW 5 - 15 | SSW 5 - 15 | SW 5 - 15 | --- - | WSW 10 - 20 |
| Friday Morning | SW 15 - 25 | S 10 - 20 | SW 10 - 20 | --- - | SW 0 - 10 |
| Friday Afternoon | SW 5 - 15 | S 5 - 15 | SW 15 - 25 | --- - | SW 0 - 10 |
| Friday Night | SW 5 - 15 | SSW 5 - 15 | SW 5 - 15 | --- - | SW 5 - 15 |
| Hurricane Ridge | Elevation |
|---|---|
| Thursday Afternoon | SW 5 - 15 |
| Thursday Night | SW 5 - 15 |
| Friday Morning | SW 15 - 25 |
| Friday Afternoon | SW 5 - 15 |
| Friday Night | SW 5 - 15 |
| Mt. Baker | Elevation |
|---|---|
| Thursday Afternoon | SW 10 - 20 |
| Thursday Night | SSW 5 - 15 |
| Friday Morning | S 10 - 20 |
| Friday Afternoon | S 5 - 15 |
| Friday Night | SSW 5 - 15 |
| Stevens and Snoqualmie Pass | Elevation |
|---|---|
| Thursday Afternoon | SW 10 - 20 |
| Thursday Night | SW 5 - 15 |
| Friday Morning | SW 10 - 20 |
| Friday Afternoon | SW 15 - 25 |
| Friday Night | SW 5 - 15 |
| Mt. Rainier | Elevation |
|---|---|
| Thursday Afternoon | --- - |
| Thursday Night | --- - |
| Friday Morning | --- - |
| Friday Afternoon | --- - |
| Friday Night | --- - |
| Mt. Hood | Elevation |
|---|---|
| Thursday Afternoon | SW 10 - 20 |
| Thursday Night | WSW 10 - 20 |
| Friday Morning | SW 0 - 10 |
| Friday Afternoon | SW 0 - 10 |
| Friday Night | SW 5 - 15 |
| Hurricane Ridge | Direction - Speed |
|---|---|
| Thursday Afternoon | SW 5 - 15 |
| Thursday Night | SW 5 - 15 |
| Friday Morning | SW 15 - 25 |
| Friday Afternoon | SW 5 - 15 |
| Friday Night | SW 5 - 15 |
| Mt. Baker | Direction - Speed |
|---|---|
| Thursday Afternoon | SW 10 - 20 |
| Thursday Night | SSW 5 - 15 |
| Friday Morning | S 10 - 20 |
| Friday Afternoon | S 5 - 15 |
| Friday Night | SSW 5 - 15 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Thursday Afternoon | SW 10 - 20 |
| Thursday Night | SW 5 - 15 |
| Friday Morning | SW 10 - 20 |
| Friday Afternoon | SW 15 - 25 |
| Friday Night | SW 5 - 15 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Thursday Afternoon | --- - |
| Thursday Night | --- - |
| Friday Morning | --- - |
| Friday Afternoon | --- - |
| Friday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| Thursday Afternoon | SW 10 - 20 |
| Thursday Night | WSW 10 - 20 |
| Friday Morning | SW 0 - 10 |
| Friday Afternoon | SW 0 - 10 |
| Friday Night | SW 5 - 15 |
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 | SW 10 - 20 | SW 20 - 30 | SW 25 - 35 | --- - | WSW 30 - 40 |
| Thursday Night | SW 20 - 30 | WSW 25 - 35 | W 25 - 35 | --- - | WSW 25 - 35 |
| Friday Morning | SW 25 - 35 | SW 30 - 40 | SW 30 - 40 | --- - | WSW 15 - 25 |
| Friday Afternoon | SW 20 - 30 | SW 30 - 40 | SW 30 - 40 | --- - | SW 20 - 30 |
| Friday Night | SW 15 - 25 | SW 30 - 40 | SW 25 - 35 | --- - | SW 20 - 30 |
| Mt. Baker | Direction - Speed |
|---|---|
| Thursday Afternoon | SW 10 - 20 |
| Thursday Night | SW 20 - 30 |
| Friday Morning | SW 25 - 35 |
| Friday Afternoon | SW 20 - 30 |
| Friday Night | SW 15 - 25 |
| Washington Pass | Direction - Speed |
|---|---|
| Thursday Afternoon | SW 20 - 30 |
| Thursday Night | WSW 25 - 35 |
| Friday Morning | SW 30 - 40 |
| Friday Afternoon | SW 30 - 40 |
| Friday Night | SW 30 - 40 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Thursday Afternoon | SW 25 - 35 |
| Thursday Night | W 25 - 35 |
| Friday Morning | SW 30 - 40 |
| Friday Afternoon | SW 30 - 40 |
| Friday Night | SW 25 - 35 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Thursday Afternoon | --- - |
| Thursday Night | --- - |
| Friday Morning | --- - |
| Friday Afternoon | --- - |
| Friday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| Thursday Afternoon | WSW 30 - 40 |
| Thursday Night | WSW 25 - 35 |
| Friday Morning | WSW 15 - 25 |
| Friday Afternoon | SW 20 - 30 |
| Friday Night | SW 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: 2:49 PM PST Thursday, November 30, 2017
Extended Weather Synopsis for Thursday night through Thursday
A cool upper level trough will dive south toward the Oregon Coast Saturday bringing with it cloudy and showery weather. An upper low may develop off the south-central Washington coast and help produce locally heavier snow showers for the southwest Cascades Saturday afternoon (Paradise, White Pass, Crystal) while the northwest Cascades begin to dry out in the afternoon.
Showers should taper off Saturday night into Sunday morning as the flow aloft turns more northerly.
A strong upper level ridge will begin to build offshore on Monday with dry and cool conditions expected. The upper level ridge looks likely to dominate our weather pattern for the next week.
Extended Weather
Olympics, Washington Cascades and Mt. Hood
Mostly cloudy with light to occasionally moderate rain and snow showers. Showers decreasing overnight.
Partly to mostly cloudy with a few scattered showers in the morning. Clearing in the afternoon. Mostly clear Sunday night.
Mostly clear and fair.
Extended Snow/Freezing Levels
| Mt. Baker | Snoqualmie Pass | Mt. Hood | Easterly Flow * | ||
|---|---|---|---|---|---|
| Saturday | Snow Level | 2000' - 3000' | 3000' - 4000' | 3000' - 4000' | |
| Saturday Night | Snow Level | 500' - 1500' | 1500' - 2500' | 2000' - 3000' | |
| Sunday | Freezing Level | 1000' - 2000' | 1500' - 2500' | 2500' - 3500' | |
| Sunday Night | Freezing Level | 0' - 500' | 0' - 500' | 1500' - 2500' | |
| Monday | Freezing Level | 1000' - 2000' | 1000' - 2000' | 2000' - 3000' |
| Mt. Baker | Elevation |
|---|---|
| Saturday |
Snow Level 2000' - 3000' |
| Saturday Night |
Snow Level 500' - 1500' |
| Sunday |
Freezing Level 1000' - 2000' |
| Sunday Night |
Freezing Level 0' - 500' |
| Monday |
Freezing Level 1000' - 2000' |
| Snoqualmie Pass | Elevation |
|---|---|
| Saturday |
Snow Level 3000' - 4000' |
| Saturday Night |
Snow Level 1500' - 2500' |
| Sunday |
Freezing Level 1500' - 2500' |
| Sunday Night |
Freezing Level 0' - 500' |
| Monday |
Freezing Level 1000' - 2000' |
| Mt. Hood | Elevation |
|---|---|
| Saturday |
Snow Level 3000' - 4000' |
| Saturday Night |
Snow Level 2000' - 3000' |
| Sunday |
Freezing Level 2500' - 3500' |
| Sunday Night |
Freezing Level 1500' - 2500' |
| Monday |
Freezing Level 2000' - 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 Nov 30, 2017
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