Jump to: Weather Forecast I Snow/Freezing Level I Precipitation I Free Winds 5k I Free Winds 9k I Extended Weather
Weather Synopsis for Friday & Thursday
High clouds are rapidly increasing over the area Friday afternoon as a Pacific frontal system advance towards our region. Light warm frontal precipitation should glance the area overnight as snow levels lower and crest level winds increase.
A burst of light to moderate precipitation with the frontal passage through the Cascades around 5 am should be followed by a cold and showery morning. The second half of Saturday should still be seasonally cool, but sunbreaks should begin to pop out by mid-day. Breezy winds in the morning should also slowly decrease in the afternoon. New snowfall accumulations above 3500 ft should locally be the highest in the Mt. Baker area and near and north of Stevens Pass where a Puget Sound Convergence Zone is expected to form in the morning. Mt. Hood will not pick up much new snow from this system.
Isolated showers should come to end Saturday night, but there may be a fair amount of high clouds overnight as an upper level trough approaches the area.
Weather Forecast
Olympics
| Friday Afternoon | Overcast with high clouds. Mild. |
| Friday Night | Cloudy with light to occasionally moderate rain and snow developing. Slow cooling trend. Increasing winds. |
| Saturday | Light rain and snow showers in the morning. Mostly cloudy with isolated light showers in the afternoon. Windy in the morning, decreasing in the afternoon. Cooler. |
| Saturday Night | Mostly cloudy with isolated showers decreasing in the evening and becoming partly cloudy with periods of high clouds. |
Washington Cascades near and west of the Crest including Stevens, Snoqualmie and White Passes
| Friday Afternoon | Overcast with high clouds. Mild. |
| Friday Night | Cloudy with light rain and snow developing after midnight, occasionally moderate Mt. Baker area. Slow cooling trend. Increasing alpine winds. |
| Saturday | Light to occasionally moderate rain and snow showers in the morning, heaviest Mt. Baker area and in the convergence zone near and north of Stevens Pass. Scattered light showers in the afternoon, mostly cloudy north Cascades and partly to mostly cloudy central and south Cascades. Windy in the morning, decreasing in the afternoon. Cooler. |
| Saturday Night | Mostly cloudy with isolated showers decreasing in the evening and becoming partly cloudy with periods of high clouds. |
East Slopes of the Washington Cascades
| Friday Afternoon | Mostly cloudy with increasing high clouds. Mild. |
| Friday Night | Cloudy with light rain and snow developing after midnight. Slow cooling trend. Increasing alpine winds. |
| Saturday | Light rain and snow showers in the morning, heaviest near the crest central and north Cascades. Partly cloudy with isolated light showers in the afternoon. Windy. Cooler. |
| Saturday Night | Partly cloudy with periods of high clouds. |
Mt. Hood
| Friday Afternoon | Mostly cloudy with increasing high clouds. Mild. |
| Friday Night | Cloudy with light rain and snow developing late tonight. Slow cooling trend. Increasing alpine winds. |
| Saturday | Light rain and snow showers in the morning, becoming partly to mostly cloudy with isolated light showers in the afternoon. Windy. Cooler. |
| Saturday Night | Partly cloudy with periods of high clouds. |
Issued: 2:02 PM PDT Friday, April 20, 2018
Snow/Freezing Level (ft)
| Hurricane Ridge | Mt. Baker | Washington Pass | Leavenworth | Stevens Pass | Snoqualmie Pass | Mt. Rainier, Crystal & White Pass | Mt. Hood | ||
|---|---|---|---|---|---|---|---|---|---|
| Friday Afternoon | Freezing Level | 6500' | 6500' | 7000' | ' | ' | 7500' | ' | 9000' |
| Friday Night | Snow Level | 4000' | 4000' | 4500' | ' | ' | 4500' | ' | 4500' |
| Saturday Morning | Snow Level | 3000' | 3000' | 3000' | ' | ' | 3000' | ' | 4000' |
| Saturday Afternoon | Snow Level | 3500' | 3500' | 4500' | ' | ' | 3500' | ' | 4500' |
| Saturday Night | Snow Level | 3000' | 3000' | 3000' | ' | ' | 3000' | ' | 4000' |
| Hurricane Ridge | Elevation |
|---|---|
| Friday Afternoon |
Freezing Level 6500' |
| Friday Night |
Snow Level 4000' |
| Saturday Morning |
Snow Level 3000' |
| Saturday Afternoon |
Snow Level 3500' |
| Saturday Night |
Snow Level 3000' |
| Mt. Baker | Elevation |
|---|---|
| Friday Afternoon |
Freezing Level 6500' |
| Friday Night |
Snow Level 4000' |
| Saturday Morning |
Snow Level 3000' |
| Saturday Afternoon |
Snow Level 3500' |
| Saturday Night |
Snow Level 3000' |
| Washington Pass | Elevation |
|---|---|
| Friday Afternoon |
Freezing Level 7000' |
| Friday Night |
Snow Level 4500' |
| Saturday Morning |
Snow Level 3000' |
| Saturday Afternoon |
Snow Level 4500' |
| Saturday Night |
Snow Level 3000' |
| Leavenworth | Elevation |
|---|---|
| Friday Afternoon |
Freezing Level ' |
| Friday Night |
Snow Level ' |
| Saturday Morning |
Snow Level ' |
| Saturday Afternoon |
Snow Level ' |
| Saturday Night |
Snow Level ' |
| Stevens Pass | Elevation |
|---|---|
| Friday Afternoon |
Freezing Level ' |
| Friday Night |
Snow Level ' |
| Saturday Morning |
Snow Level ' |
| Saturday Afternoon |
Snow Level ' |
| Saturday Night |
Snow Level ' |
| Snoqualmie Pass | Elevation |
|---|---|
| Friday Afternoon |
Freezing Level 7500' |
| Friday Night |
Snow Level 4500' |
| Saturday Morning |
Snow Level 3000' |
| Saturday Afternoon |
Snow Level 3500' |
| Saturday Night |
Snow Level 3000' |
| Mt. Rainier & Crystal | Elevation |
|---|---|
| Friday Afternoon |
Freezing Level ' |
| Friday Night |
Snow Level ' |
| Saturday Morning |
Snow Level ' |
| Saturday Afternoon |
Snow Level ' |
| Saturday Night |
Snow Level ' |
| Mt. Hood | Elevation |
|---|---|
| Friday Afternoon |
Freezing Level 9000' |
| Friday Night |
Snow Level 4500' |
| Saturday Morning |
Snow Level 4000' |
| Saturday Afternoon |
Snow Level 4500' |
| Saturday 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 | LT 0.25 |
| Mt Baker Ski Area | 0 - 0.50 | 0.25 - 0.50 |
| Washington Pass | LT 0.10 | LT 0.25 |
| Stevens Pass | LT 0.25 | LT 0.25 |
| Snoqualmie Pass | LT 0.25 | LT 0.25 |
| Mission Ridge | LT 0.10 | LT 0.10 |
| Crystal Mt | LT 0.10 | LT 0.25 |
| Paradise | LT 0.25 | LT 0.25 |
| White Pass | LT 0.25 | LT 0.10 |
| Mt Hood Meadows | LT 0.10 | LT 0.10 |
| Timberline | LT 0.10 | 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: 2:02 PM PDT Friday, April 20, 2018
Free Winds at 5000' (mph)
| Hurricane Ridge | Mt. Baker | Stevens to Snoqualmie Pass | Mt. Rainier | Mt. Hood | |
|---|---|---|---|---|---|
| Friday Afternoon | S 10 - 20 | SW 10 - 20 | WSW 5 - 15 | --- - | SW 10 - 20 |
| Friday Night | SW 20 - 30 | S 15 - 30 | SSW 10 - 20 | --- - | SW 15 - 25 |
| Saturday Morning | WSW 10 - 20 | SW 20 - 30 | SW 25 - 35 | --- - | WSW 25 - 35 |
| Saturday Afternoon | WSW 10 - 20 | SW 10 - 20 | W 15 - 25 | --- - | WNW 15 - 25 |
| Saturday Night | NW 0 - 10 | NW 0 - 10 | NW 5 - 15 | --- - | WNW 5 - 15 |
| Hurricane Ridge | Elevation |
|---|---|
| Friday Afternoon | S 10 - 20 |
| Friday Night | SW 20 - 30 |
| Saturday Morning | WSW 10 - 20 |
| Saturday Afternoon | WSW 10 - 20 |
| Saturday Night | NW 0 - 10 |
| Mt. Baker | Elevation |
|---|---|
| Friday Afternoon | SW 10 - 20 |
| Friday Night | S 15 - 30 |
| Saturday Morning | SW 20 - 30 |
| Saturday Afternoon | SW 10 - 20 |
| Saturday Night | NW 0 - 10 |
| Stevens and Snoqualmie Pass | Elevation |
|---|---|
| Friday Afternoon | WSW 5 - 15 |
| Friday Night | SSW 10 - 20 |
| Saturday Morning | SW 25 - 35 |
| Saturday Afternoon | W 15 - 25 |
| Saturday Night | NW 5 - 15 |
| Mt. Rainier | Elevation |
|---|---|
| Friday Afternoon | --- - |
| Friday Night | --- - |
| Saturday Morning | --- - |
| Saturday Afternoon | --- - |
| Saturday Night | --- - |
| Mt. Hood | Elevation |
|---|---|
| Friday Afternoon | SW 10 - 20 |
| Friday Night | SW 15 - 25 |
| Saturday Morning | WSW 25 - 35 |
| Saturday Afternoon | WNW 15 - 25 |
| Saturday Night | WNW 5 - 15 |
| Hurricane Ridge | Direction - Speed |
|---|---|
| Friday Afternoon | S 10 - 20 |
| Friday Night | SW 20 - 30 |
| Saturday Morning | WSW 10 - 20 |
| Saturday Afternoon | WSW 10 - 20 |
| Saturday Night | NW 0 - 10 |
| Mt. Baker | Direction - Speed |
|---|---|
| Friday Afternoon | SW 10 - 20 |
| Friday Night | S 15 - 30 |
| Saturday Morning | SW 20 - 30 |
| Saturday Afternoon | SW 10 - 20 |
| Saturday Night | NW 0 - 10 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Friday Afternoon | WSW 5 - 15 |
| Friday Night | SSW 10 - 20 |
| Saturday Morning | SW 25 - 35 |
| Saturday Afternoon | W 15 - 25 |
| Saturday Night | NW 5 - 15 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Friday Afternoon | --- - |
| Friday Night | --- - |
| Saturday Morning | --- - |
| Saturday Afternoon | --- - |
| Saturday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| Friday Afternoon | SW 10 - 20 |
| Friday Night | SW 15 - 25 |
| Saturday Morning | WSW 25 - 35 |
| Saturday Afternoon | WNW 15 - 25 |
| Saturday Night | WNW 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 | |
|---|---|---|---|---|---|
| Friday Afternoon | S 15 - 25 | SSW 10 - 20 | SSW 20 - 30 | --- - | SW 15 - 25 |
| Friday Night | SSW 30 - 40 | SW 30 - 40 | SW 35 - 45 | --- - | SW 40 - 50 |
| Saturday Morning | SW 30 - 40 | WSW 40 - 50 | WSW 35 - 45 | --- - | W 35 - 45 |
| Saturday Afternoon | W 20 - 30 | W 25 - 35 | W 30 - 40 | --- - | W 15 - 30 |
| Saturday Night | NW 5 - 15 | NW 5 - 15 | NW 10 - 20 | --- - | W 10 - 20 |
| Mt. Baker | Direction - Speed |
|---|---|
| Friday Afternoon | S 15 - 25 |
| Friday Night | SSW 30 - 40 |
| Saturday Morning | SW 30 - 40 |
| Saturday Afternoon | W 20 - 30 |
| Saturday Night | NW 5 - 15 |
| Washington Pass | Direction - Speed |
|---|---|
| Friday Afternoon | SSW 10 - 20 |
| Friday Night | SW 30 - 40 |
| Saturday Morning | WSW 40 - 50 |
| Saturday Afternoon | W 25 - 35 |
| Saturday Night | NW 5 - 15 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Friday Afternoon | SSW 20 - 30 |
| Friday Night | SW 35 - 45 |
| Saturday Morning | WSW 35 - 45 |
| Saturday Afternoon | W 30 - 40 |
| Saturday Night | NW 10 - 20 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Friday Afternoon | --- - |
| Friday Night | --- - |
| Saturday Morning | --- - |
| Saturday Afternoon | --- - |
| Saturday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| Friday Afternoon | SW 15 - 25 |
| Friday Night | SW 40 - 50 |
| Saturday Morning | W 35 - 45 |
| Saturday Afternoon | W 15 - 30 |
| Saturday Night | W 10 - 20 |
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: 2:02 PM PDT Friday, April 20, 2018
Extended Weather Synopsis for Thursday night through Thursday
A dry upper level trough will pass through the area mid-day. Expect a fair amount of afternoon cloudiness along the Olympics and west slopes of the Cascades Sunday afternoon due to afternoon heating and onshore flow, but otherwise dry and slightly warmer conditions are expected.
Monday and Tuesday will be quite warm as a strong upper level ridge builds over the area and slowly becomes centered over the inland PNW. Freezing levels will climb Monday and push well above 10K feet on Tuesday. There may be periods of moderate N-NE alpine winds from roughly Snoqualmie Pass to Mt. Hood as the flow becomes offshore.
Extended Weather
Olympics, Washington Cascades and Mt. Hood Area
Extended Snow/Freezing Levels
| Mt. Baker | Snoqualmie Pass | Mt. Hood | Easterly Flow * | ||
|---|---|---|---|---|---|
| Sunday | Freezing Level | 5000' - 6000' | 5000' - 6000' | 7000' - 8000' | |
| Sunday Night | Freezing Level | 5000' - 6000' | 5000' - 6000' | 7000' - 8000' | |
| Monday | Freezing Level | 8000' - 9000' | 7500' - 9000' | 8000' - 9000' | |
| Monday Night | Freezing Level | 10000' - 11000' | 10000' - 11000' | 11000' - 12000' | |
| Tuesday | Freezing Level | 10500' - 11500' | 11000' - 12000' | 11000' - 12000' |
| Mt. Baker | Elevation |
|---|---|
| Sunday |
Freezing Level 5000' - 6000' |
| Sunday Night |
Freezing Level 5000' - 6000' |
| Monday |
Freezing Level 8000' - 9000' |
| Monday Night |
Freezing Level 10000' - 11000' |
| Tuesday |
Freezing Level 10500' - 11500' |
| Snoqualmie Pass | Elevation |
|---|---|
| Sunday |
Freezing Level 5000' - 6000' |
| Sunday Night |
Freezing Level 5000' - 6000' |
| Monday |
Freezing Level 7500' - 9000' |
| Monday Night |
Freezing Level 10000' - 11000' |
| Tuesday |
Freezing Level 11000' - 12000' |
| Mt. Hood | Elevation |
|---|---|
| Sunday |
Freezing Level 7000' - 8000' |
| Sunday Night |
Freezing Level 7000' - 8000' |
| Monday |
Freezing Level 8000' - 9000' |
| Monday Night |
Freezing Level 11000' - 12000' |
| Tuesday |
Freezing Level 11000' - 12000' |
* 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 19, 2018
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