Jump to: Weather Forecast I Snow/Freezing Level I Precipitation I Free Winds 5k I Free Winds 9k I Extended Weather
Weather Synopsis for Tuesday & Tuesday
A front passed through the Cascades early Tuesday morning. Behind the front, snow levels have dropped rapidly and a broad area of low level convergence has setup over Snohomish and northern King counties. Westerly flow will continue the convergence zone at low snow levels today... with significant accumulations possible near Stevens Pass and Snoqualmie Passes above 4000 feet. Orographic showers and an unstable air mass will keep light to occasionally moderate showers going for the rest of the west slopes, Olympics, and Mt. Hood. Lighter showers and more sun-breaks are expected for the east slopes.
A longwave trough will be positioned over the PNW for the next two days, with cold air aloft creating a classic unstable spring setup. There will be a chance of thunderstorms in the afternoon and evening Tuesday and Wednesday. A shortwave trough swinging through Wednesday afternoon may enhance shower intensity and coverage in the afternoon and evening.
Weather Forecast
Olympics, Washington Cascades near and west of the crest including Stevens, Snoqualmie, and White Passes and Mt. Hood area
| Tuesday - Tuesday Evening |
Mostly cloudy with light to occasionally moderate rain and snow showers. Showers heaviest in a Puget Sound convergence zone near Stevens and Snoqualmie Passes. Cooler and breezy. Sunbreaks in the afternoon. Chance of thunderstorms afternoon and evening. |
| Tuesday Night - Wednesday Morning |
Mostly cloudy with scattered light rain and snow showers. |
| Wednesday Afternoon - Wednesday Evening |
Mostly cloudy with light to occasionally moderate rain and snow showers. Chance of thunderstorms afternoon and evening. |
| Wednesday Night |
Mostly cloudy with isolated light rain and snow showers. |
East slopes of the Washington Cascades
| Tuesday - Tuesday Evening |
Partly to mostly cloudy with scattered light rain and snow showers. Showers heaviest east slopes downwind of a Puget Sound convergence zone near Stevens and Snoqualmie Passes. Cooler and breezy. Chance of thunderstorms afternoon and evening near the Cascade crest. |
| Tuesday Night - Wednesday Morning |
Partly cloudy with isolated light rain and snow showers. |
| Wednesday Afternoon - Wednesday Evening |
Partly to mostly cloudy with scattered light rain and snow showers. Chance of thunderstorms afternoon and evening near the Cascade crest. |
| Wednesday Night |
Partly cloudy with isolated light rain and snow showers. |
Issued: 1:16 PM PDT Tuesday, March 31, 2015
Snow/Freezing Level (ft)
| Hurricane Ridge | Mt. Baker | Washington Pass | Leavenworth | Stevens Pass | Snoqualmie Pass | Mt. Rainier, Crystal & White Pass | Mt. Hood | ||
|---|---|---|---|---|---|---|---|---|---|
| Tuesday | Snow Level | 3500' | 3500' | 3500' | ' | ' | 3500' | ' | 3500' |
| Tuesday Night - Wednesday Morning | Snow Level | 2500' | 2000' | 2500' | ' | ' | 2500' | ' | 2500' |
| Wednesday Afternoon | Snow Level | 3500' | 3500' | 3500' | ' | ' | 3500' | ' | 3500' |
| Wednesday Night | Snow Level | 2500' | 2000' | 2500' | ' | ' | 2500' | ' | 2500' |
| Hurricane Ridge | Elevation |
|---|---|
| Tuesday |
Snow Level 3500' |
| Tuesday Night - Wednesday Morning |
Snow Level 2500' |
| Wednesday Afternoon |
Snow Level 3500' |
| Wednesday Night |
Snow Level 2500' |
| Mt. Baker | Elevation |
|---|---|
| Tuesday |
Snow Level 3500' |
| Tuesday Night - Wednesday Morning |
Snow Level 2000' |
| Wednesday Afternoon |
Snow Level 3500' |
| Wednesday Night |
Snow Level 2000' |
| Washington Pass | Elevation |
|---|---|
| Tuesday |
Snow Level 3500' |
| Tuesday Night - Wednesday Morning |
Snow Level 2500' |
| Wednesday Afternoon |
Snow Level 3500' |
| Wednesday Night |
Snow Level 2500' |
| Leavenworth | Elevation |
|---|---|
| Tuesday |
Snow Level ' |
| Tuesday Night - Wednesday Morning |
Snow Level ' |
| Wednesday Afternoon |
Snow Level ' |
| Wednesday Night |
Snow Level ' |
| Stevens Pass | Elevation |
|---|---|
| Tuesday |
Snow Level ' |
| Tuesday Night - Wednesday Morning |
Snow Level ' |
| Wednesday Afternoon |
Snow Level ' |
| Wednesday Night |
Snow Level ' |
| Snoqualmie Pass | Elevation |
|---|---|
| Tuesday |
Snow Level 3500' |
| Tuesday Night - Wednesday Morning |
Snow Level 2500' |
| Wednesday Afternoon |
Snow Level 3500' |
| Wednesday Night |
Snow Level 2500' |
| Mt. Rainier & Crystal | Elevation |
|---|---|
| Tuesday |
Snow Level ' |
| Tuesday Night - Wednesday Morning |
Snow Level ' |
| Wednesday Afternoon |
Snow Level ' |
| Wednesday Night |
Snow Level ' |
| Mt. Hood | Elevation |
|---|---|
| Tuesday |
Snow Level 3500' |
| Tuesday Night - Wednesday Morning |
Snow Level 2500' |
| Wednesday Afternoon |
Snow Level 3500' |
| Wednesday Night |
Snow Level 2500' |
* 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
| Tuesday | Tuesday | |
|---|---|---|
| Hurricane Ridge | LT 0.25 | LT 0.25 |
| Mt Baker Ski Area | 0.25 - 0.50 | LT 0.25 |
| Washington Pass | LT 0.25 | LT 0.10 |
| Stevens Pass | 0 - 1.00 | LT 0.25 |
| Snoqualmie Pass | 0.50 - 1.00 | LT 0.25 |
| Mission Ridge | LT 0.10 | LT 0.10 |
| Crystal Mt | LT 0.25 | LT 0.25 |
| Paradise | 0.50 - 0.75 | 0.25 - 0.50 |
| White Pass | 0 - 0.50 | LT 0.25 |
| Mt Hood Meadows | 0.50 - 0.75 | 0.25 - 0.50 |
| Timberline | 0.75 - 1.00 | 0 - 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: 1:16 PM PDT Tuesday, March 31, 2015
Free Winds at 5000' (mph)
| Hurricane Ridge | Mt. Baker | Stevens to Snoqualmie Pass | Mt. Rainier | Mt. Hood | |
|---|---|---|---|---|---|
| Tuesday Afternoon | W 10 - 20 | WSW 10 - 20 | WSW 15 - 25 | --- - | W 20 - 30 |
| Tuesday Night - Wednesday Morning | W 10 - 20 | SW 5 - 15 | W 10 - 20 | --- - | W 15 - 25 |
| Wednesday Afternoon - Wednesday Night | NW 5 - 15 | W 0 - 10 | WNW 5 - 15 | --- - | WNW 15 - 25 |
| Hurricane Ridge | Elevation |
|---|---|
| Tuesday Afternoon | W 10 - 20 |
| Tuesday Night - Wednesday Morning | W 10 - 20 |
| Wednesday Afternoon - Wednesday Night | NW 5 - 15 |
| Mt. Baker | Elevation |
|---|---|
| Tuesday Afternoon | WSW 10 - 20 |
| Tuesday Night - Wednesday Morning | SW 5 - 15 |
| Wednesday Afternoon - Wednesday Night | W 0 - 10 |
| Stevens and Snoqualmie Pass | Elevation |
|---|---|
| Tuesday Afternoon | WSW 15 - 25 |
| Tuesday Night - Wednesday Morning | W 10 - 20 |
| Wednesday Afternoon - Wednesday Night | WNW 5 - 15 |
| Mt. Rainier | Elevation |
|---|---|
| Tuesday Afternoon | --- - |
| Tuesday Night - Wednesday Morning | --- - |
| Wednesday Afternoon - Wednesday Night | --- - |
| Mt. Hood | Elevation |
|---|---|
| Tuesday Afternoon | W 20 - 30 |
| Tuesday Night - Wednesday Morning | W 15 - 25 |
| Wednesday Afternoon - Wednesday Night | WNW 15 - 25 |
| Hurricane Ridge | Direction - Speed |
|---|---|
| Tuesday Afternoon | W 10 - 20 |
| Tuesday Night - Wednesday Morning | W 10 - 20 |
| Wednesday Afternoon - Wednesday Night | NW 5 - 15 |
| Mt. Baker | Direction - Speed |
|---|---|
| Tuesday Afternoon | WSW 10 - 20 |
| Tuesday Night - Wednesday Morning | SW 5 - 15 |
| Wednesday Afternoon - Wednesday Night | W 0 - 10 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Tuesday Afternoon | WSW 15 - 25 |
| Tuesday Night - Wednesday Morning | W 10 - 20 |
| Wednesday Afternoon - Wednesday Night | WNW 5 - 15 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Tuesday Afternoon | --- - |
| Tuesday Night - Wednesday Morning | --- - |
| Wednesday Afternoon - Wednesday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| Tuesday Afternoon | W 20 - 30 |
| Tuesday Night - Wednesday Morning | W 15 - 25 |
| Wednesday Afternoon - Wednesday Night | WNW 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 | |
|---|---|---|---|---|---|
| Tuesday | WNW 20 - 30 | W 25 - 35 | WNW 25 - 35 | --- - | WNW 25 - 35 |
| Tuesday Night - Wednesday Morning | W 15 - 25 | WNW 15 - 25 | WNW 20 - 30 | --- - | WNW 25 - 35 |
| Wednesday Afternoon - Wednesday Night | NW 10 - 20 | NW 10 - 20 | NW 15 - 25 | --- - | NW 20 - 30 |
| Mt. Baker | Direction - Speed |
|---|---|
| Tuesday | WNW 20 - 30 |
| Tuesday Night - Wednesday Morning | W 15 - 25 |
| Wednesday Afternoon - Wednesday Night | NW 10 - 20 |
| Washington Pass | Direction - Speed |
|---|---|
| Tuesday | W 25 - 35 |
| Tuesday Night - Wednesday Morning | WNW 15 - 25 |
| Wednesday Afternoon - Wednesday Night | NW 10 - 20 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Tuesday | WNW 25 - 35 |
| Tuesday Night - Wednesday Morning | WNW 20 - 30 |
| Wednesday Afternoon - Wednesday Night | NW 15 - 25 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Tuesday | --- - |
| Tuesday Night - Wednesday Morning | --- - |
| Wednesday Afternoon - Wednesday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| Tuesday | WNW 25 - 35 |
| Tuesday Night - Wednesday Morning | WNW 25 - 35 |
| Wednesday Afternoon - Wednesday Night | NW 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: 1:16 PM PDT Tuesday, March 31, 2015
Extended Weather Synopsis for Tuesday night through Tuesday
Snow levels will remain cool through the entire forecast period, notable because extended cool periods have been sorely lacking this season. Thursday should be a lull between active weather as a transitory shortwave ridge shifts over the area. However, there should be enough low level moisture leftover to keep it mostly cloudy with a chance of showers along the west slopes. Forecast models now have the next frontal system sliding from the northwest and arriving a bit earlier...with high and mid clouds spreading over the Olympics and north Cascades later Thursday afternoon.
Light rain and snow should develop over the entire area by early Friday morning with a weak N-S oriented front passing through sometime in the afternoon or evening. A cold upper level low will meander south along the PNW coast over the weekend leading to low snow levels, a mix of sun and clouds and generally light showers.
Extended Weather
Olympics, Washington Cascades near and west of the crest including Stevens, Snoqualmie, and White Passes and Mt. Hood Area
Partly cloudy becoming mostly cloudy in the afternoon and evening. Chance of light rain and snow showers.
Light rain and snow developing Olympics and north Cascades and spreading south Friday morning.
Mostly cloudy with light to occasionally moderate rain and snow showers Olympics, west slopes of the Cascades and Mt. Hood area. Partly to mostly cloudy with scattered light rain and snow showers east slopes of the Cascades.
Extended Snow/Freezing Levels
| Mt. Baker | Snoqualmie Pass | Mt. Hood | Easterly Flow * | ||
|---|---|---|---|---|---|
| Thursday - Saturday | Snow Level | 2500' - 3500' | 2500' - 3500' | 3000' - 4000' |
| Mt. Baker | Elevation |
|---|---|
| Thursday - Saturday |
Snow Level 2500' - 3500' |
| Snoqualmie Pass | Elevation |
|---|---|
| Thursday - Saturday |
Snow Level 2500' - 3500' |
| Mt. Hood | Elevation |
|---|---|
| Thursday - Saturday |
Snow Level 3000' - 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.
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 31, 2015
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