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 & Thursday
Weak warm frontal moisture will slip under the ridge located offshore at 130W, bringing some light rain and snow to the area today with moderate NW flow aloft. The PNW is centered between a warmer air mass to our south and a much colder air mass to the north and as a result, there is a tight N-S gradient for snow levels across the area with much warmer air over Mt. Hood and snow levels near sea level for much of the Washington Cascades
A developing low offshore will renew warm frontal precipitation over the Olympics and north Cascades Thursday morning with precipitation spreading south during the daylight hours. An occluded front will pass through Thursday evening with a transition to showers overnight. Snow levels will gradually rise during the day on Thursday and also Thursday night. Easterly flow through the Passes should keep the precipitation type as mainly as snow during the day with a likely switch to rain for Snoqualmie in the evening and for Stevens after midnight. Mt. Hood looks mild with potentially heavy rain below 7000 feet Thursday night.
Weather Forecast
Olympics
| Wednesday | Cloudy with periods of light snow. |
| Wednesday Night | Cloudy with periods of light rain and snow. Warming trend. |
| Thursday | Light to occasionally moderate rain and snow. Slow warming trend. |
| Thursday Night | Light rain and snow becoming lighter showers overnight. |
Washington Cascades near and west of the Crest including Stevens, Snoqualmie and White Passes
| Wednesday | Cloudy with periods of light snow. |
| Wednesday Night | Cloudy with periods of light snow increasing after midnight. Slight warming trend. |
| Thursday | Light to moderate rain and snow, heaviest Mt. Rainier area. Slow warming trend mainly west of the Cascade Passes. Any mixed precipitation or rain at Snoqualmie Pass Thursday morning quickly changing back to snow. |
| Thursday Night | Moderate rain and snow in the evening becoming lighter showers after midnight. Warming trend. |
East Slopes of the Washington Cascades
| Wednesday | Cloudy with periods of light snow. |
| Wednesday Night | Cloudy with periods of light snow. |
| Thursday | Light rain and snow. Slow warming trend. |
| Thursday Night | Light to occasionally moderate rain and snow in the evening becoming lighter showers overnight. Warming trend. |
Mt. Hood
| Wednesday | Cloudy with periods of light rain and snow increasing in the afternoon. |
| Wednesday Night | Light rain and snow decreasing after midnight. |
| Thursday | Cloudy with periods of light rain and snow increasing in the afternoon. Warming trend. Increasing winds. |
| Thursday Night | Moderate to heavy rain and snow becoming showers late. Windy. Warmer. |
Issued: 3:32 PM PST Wednesday, December 27, 2017
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 * | 3000' | 1500' | 1500' | ' | ' | 2500' | ' | 5000' |
| Wednesday Night | Snow Level * | 4000' | 2500' | 1500' | ' | ' | 3000' | ' | 5000' |
| Thursday Morning | Snow Level * | 4500' | 3000' | 2500' | ' | ' | 3000' | ' | 5500' |
| Thursday Afternoon | Snow Level * | 5000' | 3500' | 3000' | ' | ' | 3500' | ' | 7000' |
| Thursday Night | Snow Level | 6000' | 4500' | 4000' | ' | ' | 5000' | ' | 7500' |
| Hurricane Ridge | Elevation |
|---|---|
| Wednesday Afternoon |
Snow Level 3000' (Easterly Flow *) |
| Wednesday Night |
Snow Level 4000' (Easterly Flow *) |
| Thursday Morning |
Snow Level 4500' (Easterly Flow *) |
| Thursday Afternoon |
Snow Level 5000' (Easterly Flow *) |
| Thursday Night |
Snow Level 6000' |
| Mt. Baker | Elevation |
|---|---|
| Wednesday Afternoon |
Snow Level 1500' (Easterly Flow *) |
| Wednesday Night |
Snow Level 2500' (Easterly Flow *) |
| Thursday Morning |
Snow Level 3000' (Easterly Flow *) |
| Thursday Afternoon |
Snow Level 3500' (Easterly Flow *) |
| Thursday Night |
Snow Level 4500' |
| Washington Pass | Elevation |
|---|---|
| Wednesday Afternoon |
Snow Level 1500' (Easterly Flow *) |
| Wednesday Night |
Snow Level 1500' (Easterly Flow *) |
| Thursday Morning |
Snow Level 2500' (Easterly Flow *) |
| Thursday Afternoon |
Snow Level 3000' (Easterly Flow *) |
| Thursday Night |
Snow Level 4000' |
| 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 ' |
| 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 ' |
| Snoqualmie Pass | Elevation |
|---|---|
| Wednesday Afternoon |
Snow Level 2500' (Easterly Flow *) |
| Wednesday Night |
Snow Level 3000' (Easterly Flow *) |
| Thursday Morning |
Snow Level 3000' (Easterly Flow *) |
| Thursday Afternoon |
Snow Level 3500' (Easterly Flow *) |
| Thursday Night |
Snow Level 5000' |
| 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 ' |
| Mt. Hood | Elevation |
|---|---|
| Wednesday Afternoon |
Snow Level 5000' (Easterly Flow *) |
| Wednesday Night |
Snow Level 5000' (Easterly Flow *) |
| Thursday Morning |
Snow Level 5500' (Easterly Flow *) |
| Thursday Afternoon |
Snow Level 7000' (Easterly Flow *) |
| Thursday Night |
Snow Level 7500' |
* 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 | 0.25 - 0.50 |
| Mt Baker Ski Area | 0 - 0.50 | 0.75 - 1.00 |
| Washington Pass | LT 0.25 | 0 - 0.50 |
| Stevens Pass | 0.25 - 0.50 | 1.00 - 1.50 |
| Snoqualmie Pass | 0 - 0.50 | 0 - 1.50 |
| Mission Ridge | LT 0.10 | LT 0.25 |
| Crystal Mt | LT 0.10 | 0 - 0.50 |
| Paradise | 0.25 - 0.50 | 0 - 1.50 |
| White Pass | LT 0.25 | 0.50 - 1.00 |
| Mt Hood Meadows | LT 0.25 | 1.50 - 2.00 |
| Timberline | 0.25 - 0.50 | 2.00 - 2.50 |
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: 3:32 PM PST Wednesday, December 27, 2017
Free Winds at 5000' (mph)
| Hurricane Ridge | Mt. Baker | Stevens to Snoqualmie Pass | Mt. Rainier | Mt. Hood | |
|---|---|---|---|---|---|
| Wednesday Afternoon | WSW 5 - 15 | WSW 0 - 10 | WSW 10 - 20 | --- - | WSW 20 - 30 |
| Wednesday Night | SW 5 - 15 | WSW 0 - 10 | SW 5 - 15 | --- - | WSW 10 - 20 |
| Thursday Morning | SW 10 - 20 | S 5 - 15 | SW 10 - 20 | --- - | SW 5 - 15 |
| Thursday Afternoon | S 15 - 25 | S 10 - 20 | S 5 - 15 | --- - | SW 15 - 25 |
| Thursday Night | SW 15 - 25 | S 10 - 20 | SW 25 - 35 | --- - | WSW 35 - 45 |
| Hurricane Ridge | Elevation |
|---|---|
| Wednesday Afternoon | WSW 5 - 15 |
| Wednesday Night | SW 5 - 15 |
| Thursday Morning | SW 10 - 20 |
| Thursday Afternoon | S 15 - 25 |
| Thursday Night | SW 15 - 25 |
| Mt. Baker | Elevation |
|---|---|
| Wednesday Afternoon | WSW 0 - 10 |
| Wednesday Night | WSW 0 - 10 |
| Thursday Morning | S 5 - 15 |
| Thursday Afternoon | S 10 - 20 |
| Thursday Night | S 10 - 20 |
| Stevens and Snoqualmie Pass | Elevation |
|---|---|
| Wednesday Afternoon | WSW 10 - 20 |
| Wednesday Night | SW 5 - 15 |
| Thursday Morning | SW 10 - 20 |
| Thursday Afternoon | S 5 - 15 |
| Thursday Night | SW 25 - 35 |
| Mt. Rainier | Elevation |
|---|---|
| Wednesday Afternoon | --- - |
| Wednesday Night | --- - |
| Thursday Morning | --- - |
| Thursday Afternoon | --- - |
| Thursday Night | --- - |
| Mt. Hood | Elevation |
|---|---|
| Wednesday Afternoon | WSW 20 - 30 |
| Wednesday Night | WSW 10 - 20 |
| Thursday Morning | SW 5 - 15 |
| Thursday Afternoon | SW 15 - 25 |
| Thursday Night | WSW 35 - 45 |
| Hurricane Ridge | Direction - Speed |
|---|---|
| Wednesday Afternoon | WSW 5 - 15 |
| Wednesday Night | SW 5 - 15 |
| Thursday Morning | SW 10 - 20 |
| Thursday Afternoon | S 15 - 25 |
| Thursday Night | SW 15 - 25 |
| Mt. Baker | Direction - Speed |
|---|---|
| Wednesday Afternoon | WSW 0 - 10 |
| Wednesday Night | WSW 0 - 10 |
| Thursday Morning | S 5 - 15 |
| Thursday Afternoon | S 10 - 20 |
| Thursday Night | S 10 - 20 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Wednesday Afternoon | WSW 10 - 20 |
| Wednesday Night | SW 5 - 15 |
| Thursday Morning | SW 10 - 20 |
| Thursday Afternoon | S 5 - 15 |
| Thursday Night | SW 25 - 35 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Wednesday Afternoon | --- - |
| Wednesday Night | --- - |
| Thursday Morning | --- - |
| Thursday Afternoon | --- - |
| Thursday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| Wednesday Afternoon | WSW 20 - 30 |
| Wednesday Night | WSW 10 - 20 |
| Thursday Morning | SW 5 - 15 |
| Thursday Afternoon | SW 15 - 25 |
| Thursday Night | WSW 35 - 45 |
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 | W 30 - 40 | W 30 - 40 | W 30 - 40 | --- - | W 30 - 40 |
| Wednesday Night | W 20 - 30 | W 20 - 30 | WSW 25 - 35 | --- - | WSW 30 - 40 |
| Thursday Morning | SW 15 - 25 | SW 20 - 30 | SW 30 - 40 | --- - | SW 40 - 50 |
| Thursday Afternoon | SW 15 - 25 | SW 15 - 25 | SW 35 - 45 | --- - | WSW 50 - 60 |
| Thursday Night | SW 20 - 30 | SW 20 - 30 | WSW 35 - 45 | --- - | WSW 45 - 55 |
| Mt. Baker | Direction - Speed |
|---|---|
| Wednesday Afternoon | W 30 - 40 |
| Wednesday Night | W 20 - 30 |
| Thursday Morning | SW 15 - 25 |
| Thursday Afternoon | SW 15 - 25 |
| Thursday Night | SW 20 - 30 |
| Washington Pass | Direction - Speed |
|---|---|
| Wednesday Afternoon | W 30 - 40 |
| Wednesday Night | W 20 - 30 |
| Thursday Morning | SW 20 - 30 |
| Thursday Afternoon | SW 15 - 25 |
| Thursday Night | SW 20 - 30 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Wednesday Afternoon | W 30 - 40 |
| Wednesday Night | WSW 25 - 35 |
| Thursday Morning | SW 30 - 40 |
| Thursday Afternoon | SW 35 - 45 |
| Thursday Night | WSW 35 - 45 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Wednesday Afternoon | --- - |
| Wednesday Night | --- - |
| Thursday Morning | --- - |
| Thursday Afternoon | --- - |
| Thursday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| Wednesday Afternoon | W 30 - 40 |
| Wednesday Night | WSW 30 - 40 |
| Thursday Morning | SW 40 - 50 |
| Thursday Afternoon | WSW 50 - 60 |
| Thursday Night | WSW 45 - 55 |
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: 3:32 PM PST Wednesday, December 27, 2017
Extended Weather Synopsis for Thursday night through Thursday
Yet another developing Pacific low pressure system will quickly approach the area on Friday with increasing precipitation in the afternoon for the Washington Cascades. Mt. Hood likely won't see much of a break in the action as the moderate to occasionally heavy precipitation at mild snow levels continue from Thursday night.
Lighter precipitation Friday morning with weak easterly flow may allow for mixed precipitation in the Cascade Passes before changing back to wet snow. The surface low is forecast to track south of the Olympics and across the Puget Sound on Friday, and should bring a more significant shot of precipitation for the east slopes through Friday night.
A fast moving shortwave in NW flow aloft should keep mainly light showers going at much cooler snow levels on Saturday. Strong upper level ridging will build offshore Saturday night and Sunday bringing drier conditions. Moderate offshore winds should develop on Sunday through the Passes and perhaps up to crest level.
Extended Weather
Olympics, Washington Cascades and Mt. Hood Area
Extended Snow/Freezing Levels
| Mt. Baker | Snoqualmie Pass | Mt. Hood | Easterly Flow * | ||
|---|---|---|---|---|---|
| Friday Morning | Snow Level | 4000' - 5000' | 3500' - 4500' | 6500' - 7500' | |
| Friday Night | Snow Level | 1000' - 2000' | 2000' - 3000' | 2500' - 3500' | |
| Saturday | Snow Level | 1500' - 2500' | 2000' - 3000' | 2500' - 3500' | |
| Saturday Night | Freezing Level | 0' - 1000' | 500' - 1500' | 2000' - 3000' | |
| Sunday | Freezing Level | 3000' - 4000' | 2000' - 3000' | 3500' - 4500' | * |
| Friday Afternoon | Snow Level | 3000' - 4000' | 4000' - 5000' | 6500' - 7500' | * |
| Mt. Baker | Elevation |
|---|---|
| Friday Morning |
Snow Level 4000' - 5000' |
| Friday Night |
Snow Level 1000' - 2000' |
| Saturday |
Snow Level 1500' - 2500' |
| Saturday Night |
Freezing Level 0' - 1000' |
| Sunday |
Freezing Level 3000' - 4000' (Easterly Flow *) |
| Friday Afternoon |
Snow Level 3000' - 4000' (Easterly Flow *) |
| Snoqualmie Pass | Elevation |
|---|---|
| Friday Morning |
Snow Level 3500' - 4500' |
| Friday Night |
Snow Level 2000' - 3000' |
| Saturday |
Snow Level 2000' - 3000' |
| Saturday Night |
Freezing Level 500' - 1500' |
| Sunday |
Freezing Level 2000' - 3000' (Easterly Flow *) |
| Friday Afternoon |
Snow Level 4000' - 5000' (Easterly Flow *) |
| Mt. Hood | Elevation |
|---|---|
| Friday Morning |
Snow Level 6500' - 7500' |
| Friday Night |
Snow Level 2500' - 3500' |
| Saturday |
Snow Level 2500' - 3500' |
| Saturday Night |
Freezing Level 2000' - 3000' |
| Sunday |
Freezing Level 3500' - 4500' (Easterly Flow *) |
| Friday Afternoon |
Snow Level 6500' - 7500' (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 Dec 27, 2017
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