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 & Sunday
An upper level ridge over central British Columbia and Alberta will keep weather systems out of the PNW for at least another day as a splitting frontal system out near 135 W will make little eastward progress. However, a weak upper level low over Washington state should allow for afternoon clouds and showers to develop with a slight chance of a thunderstorm over the mountains.
The real story will be a frontal system that approaches Friday and passes through the Cascades Friday night. This system should be driven by a modest 100 kt jet located near the WA/OR border. Behind the front, a period of orographic westerly flow will ensue as seasonally cool snow levels settle in for the weekend.
Weather Forecast
Olympics
| Thursday Afternoon - Thursday Evening |
Partly sunny with scattered light rain and snow showers. Slight chance of thunderstorms. |
| Thursday Night - Friday Morning |
Increasing high clouds. |
| Friday Afternoon |
Cloudy with light rain and snow. |
| Friday Night |
Windy with light to moderate rain and snow becoming showers Friday night. Cooling trend. |
Washington Cascades near and west of the crest including Stevens, Snoqualmie, and White Passes and Mt. Hood area
| Thursday Morning |
Mostly clear. |
| Thursday Afternoon - Thursday Evening |
Partly sunny with scattered light rain and snow showers. Slight chance of thunderstorms. |
| Thursday Night - Friday Morning |
Mostly clear with increasing high clouds north Cascades early Friday morning. |
| Friday Afternoon |
Becoming cloudy with light rain and snow developing north Cascades in the afternoon. |
| Friday Night |
Becoming windy with light to moderate rain and snow becoming showers late Friday night. Rain and snow occasionally heavy Mt. Baker area Friday night. Cooling trend. |
East slopes of the Washington Cascades
| Thursday Afternoon - Thursday Evening |
Partly sunny with scattered light rain and snow showers. Slight chance of thunderstorms. |
| Thursday Night - Friday Morning |
Mostly clear with increasing high clouds northeast Cascades early Friday morning. |
| Friday Afternoon |
Becoming cloudy with light rain and snow developing northeast Cascades late in the afternoon. |
| Friday Night |
Becoming windy with light to occasionally moderate rain and snow near the crest Friday night. Cooling trend. |
Issued: 1:49 PM PDT Thursday, April 9, 2015
Snow/Freezing Level (ft)
| Hurricane Ridge | Mt. Baker | Washington Pass | Leavenworth | Stevens Pass | Snoqualmie Pass | Mt. Rainier, Crystal & White Pass | Mt. Hood | ||
|---|---|---|---|---|---|---|---|---|---|
| Thursday Afternoon - Friday Morning | Freezing Level | 6000' | 6500' | 6500' | ' | ' | 6500' | ' | 7000' |
| Friday Afternoon | Snow Level | 4000' | 4500' | 5000' | ' | ' | 5000' | ' | 5500' |
| Friday Evening | Snow Level | 3500' | 4000' | 4500' | ' | ' | 4500' | ' | 4500' |
| Friday Night | Snow Level | 2000' | 2000' | 2000' | ' | ' | 2500' | ' | 3500' |
| Hurricane Ridge | Elevation |
|---|---|
| Thursday Afternoon - Friday Morning |
Freezing Level 6000' |
| Friday Afternoon |
Snow Level 4000' |
| Friday Evening |
Snow Level 3500' |
| Friday Night |
Snow Level 2000' |
| Mt. Baker | Elevation |
|---|---|
| Thursday Afternoon - Friday Morning |
Freezing Level 6500' |
| Friday Afternoon |
Snow Level 4500' |
| Friday Evening |
Snow Level 4000' |
| Friday Night |
Snow Level 2000' |
| Washington Pass | Elevation |
|---|---|
| Thursday Afternoon - Friday Morning |
Freezing Level 6500' |
| Friday Afternoon |
Snow Level 5000' |
| Friday Evening |
Snow Level 4500' |
| Friday Night |
Snow Level 2000' |
| Leavenworth | Elevation |
|---|---|
| Thursday Afternoon - Friday Morning |
Freezing Level ' |
| Friday Afternoon |
Snow Level ' |
| Friday Evening |
Snow Level ' |
| Friday Night |
Snow Level ' |
| Stevens Pass | Elevation |
|---|---|
| Thursday Afternoon - Friday Morning |
Freezing Level ' |
| Friday Afternoon |
Snow Level ' |
| Friday Evening |
Snow Level ' |
| Friday Night |
Snow Level ' |
| Snoqualmie Pass | Elevation |
|---|---|
| Thursday Afternoon - Friday Morning |
Freezing Level 6500' |
| Friday Afternoon |
Snow Level 5000' |
| Friday Evening |
Snow Level 4500' |
| Friday Night |
Snow Level 2500' |
| Mt. Rainier & Crystal | Elevation |
|---|---|
| Thursday Afternoon - Friday Morning |
Freezing Level ' |
| Friday Afternoon |
Snow Level ' |
| Friday Evening |
Snow Level ' |
| Friday Night |
Snow Level ' |
| Mt. Hood | Elevation |
|---|---|
| Thursday Afternoon - Friday Morning |
Freezing Level 7000' |
| Friday Afternoon |
Snow Level 5500' |
| Friday Evening |
Snow Level 4500' |
| Friday Night |
Snow Level 3500' |
* 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
| Sunday | Sunday | |
|---|---|---|
| Hurricane Ridge | LT 0.10 | 0 - 0.50 |
| Mt Baker Ski Area | LT 0.10 | 1.00 - 1.50 |
| Washington Pass | LT 0.10 | 0 - 0.50 |
| Stevens Pass | LT 0.10 | 0 - 0.50 |
| Snoqualmie Pass | LT 0.10 | 0 - 0.75 |
| Mission Ridge | LT 0.25 | LT 0.10 |
| Crystal Mt | LT 0.10 | 0 - 0.50 |
| Paradise | LT 0.10 | 0.75 - 1.00 |
| White Pass | LT 0.10 | 0.50 - 0.75 |
| Mt Hood Meadows | LT 0.10 | 0.50 - 0.75 |
| Timberline | LT 0.10 | 0 - 0.75 |
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: 1:49 PM PDT Thursday, April 9, 2015
Free Winds at 5000' (mph)
| Hurricane Ridge | Mt. Baker | Stevens to Snoqualmie Pass | Mt. Rainier | Mt. Hood | |
|---|---|---|---|---|---|
| Thursday | VAR 0 - 10 | VAR 0 - 10 | VAR 0 - 10 | --- - | VAR 0 - 10 |
| Thursday Night - Friday Morning | SSW 5 - 15 | SSW 5 - 15 | SW 5 - 15 | --- - | SW 5 - 15 |
| Friday Afternoon | SW 20 - 30 | S 25 - 35 | SW 15 - 30 | --- - | SW 20 - 30 |
| Friday Night | WSW 20 - 30 | SW 25 - 35 | SW 30 - 40 | --- - | SW 35 - 45 |
| Hurricane Ridge | Elevation |
|---|---|
| Thursday | VAR 0 - 10 |
| Thursday Night - Friday Morning | SSW 5 - 15 |
| Friday Afternoon | SW 20 - 30 |
| Friday Night | WSW 20 - 30 |
| Mt. Baker | Elevation |
|---|---|
| Thursday | VAR 0 - 10 |
| Thursday Night - Friday Morning | SSW 5 - 15 |
| Friday Afternoon | S 25 - 35 |
| Friday Night | SW 25 - 35 |
| Stevens and Snoqualmie Pass | Elevation |
|---|---|
| Thursday | VAR 0 - 10 |
| Thursday Night - Friday Morning | SW 5 - 15 |
| Friday Afternoon | SW 15 - 30 |
| Friday Night | SW 30 - 40 |
| Mt. Rainier | Elevation |
|---|---|
| Thursday | --- - |
| Thursday Night - Friday Morning | --- - |
| Friday Afternoon | --- - |
| Friday Night | --- - |
| Mt. Hood | Elevation |
|---|---|
| Thursday | VAR 0 - 10 |
| Thursday Night - Friday Morning | SW 5 - 15 |
| Friday Afternoon | SW 20 - 30 |
| Friday Night | SW 35 - 45 |
| Hurricane Ridge | Direction - Speed |
|---|---|
| Thursday | VAR 0 - 10 |
| Thursday Night - Friday Morning | SSW 5 - 15 |
| Friday Afternoon | SW 20 - 30 |
| Friday Night | WSW 20 - 30 |
| Mt. Baker | Direction - Speed |
|---|---|
| Thursday | VAR 0 - 10 |
| Thursday Night - Friday Morning | SSW 5 - 15 |
| Friday Afternoon | S 25 - 35 |
| Friday Night | SW 25 - 35 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Thursday | VAR 0 - 10 |
| Thursday Night - Friday Morning | SW 5 - 15 |
| Friday Afternoon | SW 15 - 30 |
| Friday Night | SW 30 - 40 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Thursday | --- - |
| Thursday Night - Friday Morning | --- - |
| Friday Afternoon | --- - |
| Friday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| Thursday | VAR 0 - 10 |
| Thursday Night - Friday Morning | SW 5 - 15 |
| Friday Afternoon | SW 20 - 30 |
| Friday Night | SW 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 | |
|---|---|---|---|---|---|
| Thursday | S 5 - 15 | S 0 - 10 | S 0 - 10 | --- - | SW 5 - 15 |
| Thursday Night - Friday Morning | SW 15 - 25 | SW 10 - 20 | SW 15 - 25 | --- - | SW 15 - 25 |
| Friday Afternoon | SW 35 - 45 | SW 20 - 30 | SW 25 - 35 | --- - | SW 35 - 45 |
| Friday Night | WSW 30 - 40 | WSW 35 - 45 | W 35 - 45 | --- - | WSW 40 - 50 |
| Mt. Baker | Direction - Speed |
|---|---|
| Thursday | S 5 - 15 |
| Thursday Night - Friday Morning | SW 15 - 25 |
| Friday Afternoon | SW 35 - 45 |
| Friday Night | WSW 30 - 40 |
| Washington Pass | Direction - Speed |
|---|---|
| Thursday | S 0 - 10 |
| Thursday Night - Friday Morning | SW 10 - 20 |
| Friday Afternoon | SW 20 - 30 |
| Friday Night | WSW 35 - 45 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Thursday | S 0 - 10 |
| Thursday Night - Friday Morning | SW 15 - 25 |
| Friday Afternoon | SW 25 - 35 |
| Friday Night | W 35 - 45 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Thursday | --- - |
| Thursday Night - Friday Morning | --- - |
| Friday Afternoon | --- - |
| Friday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| Thursday | SW 5 - 15 |
| Thursday Night - Friday Morning | SW 15 - 25 |
| Friday Afternoon | SW 35 - 45 |
| Friday Night | WSW 40 - 50 |
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: 1:49 PM PDT Thursday, April 9, 2015
Extended Weather Synopsis for Sunday night through Sunday
Cool westerly flow Saturday should maintain a breezy and showery day, with modest additional accumulations possible along the west slopes especially near a potential area of convergence in the central Cascades between Stevens and Snoqualmie Passes. Showers should continue through the evening and ease off either Saturday night or early Sunday morning.
Another low pressure system and the associated frontal band will approach Sunday with periods of light rain and snow glancing the Olympics and north Cascades and maintaining cloudy skies over much of the area. The timing is uncertain, but the latest model runs have a relatively cool frontal system passing through the area Monday... bringing another opportunity for modest mid-April snowfall.
Extended Weather
Olympics, Washington Cascades near and west of the crest including Stevens, Snoqualmie, and White Passes and Mt. Hood area
Mostly cloudy with light to moderate orographic rain and snow showers. Potential higher accumulations near a Puget Sound convergence zone between Stevens and Snoqualmie Passes Saturday afternoon and evening. Cooler and breezy.
Mostly cloudy with light rain and snow showers.
Cloudy Olympics and north Cascades with periods of light rain and snow. Mostly cloudy central and south part. Slight warming trend.
Light to moderate rain and snow.
East slopes of the Washington Cascades
Mostly cloudy with light to occasionally moderate rain and snow showers. Cooler and breezy.
Partly to mostly cloudy with isolated light rain and snow showers.
Cloudy northeast Cascades with periods of very light rain and snow. Mostly cloudy central and south part. Slight warming trend.
Light rain and snow.
Extended Snow/Freezing Levels
| Mt. Baker | Snoqualmie Pass | Mt. Hood | Easterly Flow * | ||
|---|---|---|---|---|---|
| Saturday - Sunday Morning | Snow Level | 2000' - 3000' | 2000' - 3000' | 3000' - 4000' | |
| Sunday Afternoon - Monday Morning | Snow Level | 2500' - 3500' | 3000' - 4000' | 4500' - 5500' | |
| Monday Afternoon | Snow Level | 3000' - 4000' | 3500' - 4500' | 4000' - 5000' |
| Mt. Baker | Elevation |
|---|---|
| Saturday - Sunday Morning |
Snow Level 2000' - 3000' |
| Sunday Afternoon - Monday Morning |
Snow Level 2500' - 3500' |
| Monday Afternoon |
Snow Level 3000' - 4000' |
| Snoqualmie Pass | Elevation |
|---|---|
| Saturday - Sunday Morning |
Snow Level 2000' - 3000' |
| Sunday Afternoon - Monday Morning |
Snow Level 3000' - 4000' |
| Monday Afternoon |
Snow Level 3500' - 4500' |
| Mt. Hood | Elevation |
|---|---|
| Saturday - Sunday Morning |
Snow Level 3000' - 4000' |
| Sunday Afternoon - Monday Morning |
Snow Level 4500' - 5500' |
| Monday Afternoon |
Snow Level 4000' - 5000' |
* 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 9, 2015
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