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 & Friday
After a relatively cool start this morning with most mountain sites in the mid to upper 20s, freezing levels will peak into the 7500-9000 ft range over the Olympics and Cascades this afternoon. As of 1 PM, many NWAC stations are in the 40s with a few pushing into the 50s as a high amplitude upper level ridge moves over the West Coast. As has been the case with dry weather forecasts as of late, there are a few caveats. The next approaching frontal system should start to spread some high cloud over the area from the SW in the late afternoon/early evening. Also, offshore gradients will increase though the Passes creating locally breezy conditions this afternoon and tonight. Crest level E-SE winds particularly in the southeast/central-east Washington Cascades and the Mt. Hood area will increase overnight as the next Pacific frontal system approaches.
Mid and high level clouds will increase Friday night in advance of the front, but precipitation should hold off until Saturday morning. Rain and snow will lift northeast over the area during the day on Saturday, followed by post-frontal showers late Saturday afternoon/evening. Showers should taper off Saturday night.
Weather Forecast
Olympics
| Friday |
Mostly sunny. Warmer. Increasing high clouds late in the afternoon. |
| Friday Night |
Becoming partly to mostly cloudy. |
| Saturday |
Light to occasionally moderate rain and snow developing mid-morning and becoming light rain and snow showers in the afternoon. |
| Saturday Night |
Mostly cloudy with light rain and snow showers tapering down overnight. |
Washington Cascades near and west of the crest including Stevens, Snoqualmie, and White Passes
| Friday |
Mostly sunny. Warmer. Locally breezy E-SE winds. Increasing high clouds late in the afternoon. |
| Friday Night |
Becoming partly to mostly cloudy. Locally breezy E-SE winds. |
| Saturday |
Light rain and snow developing late morning and becoming light to occasionally moderate in the afternoon. A few sunbreaks possible in the southwest Cascades in the afternoon. |
| Saturday Night |
Mostly cloudy with light rain and snow showers tapering down overnight, except occasionally moderate Mt. Baker area. |
East slopes of the Washington Cascades
| Friday |
Mostly sunny. Warmer. |
| Friday Night |
Becoming partly cloudy with increasing high clouds. |
| Saturday - Saturday Evening |
Cloudy with light rain and snow developing late morning, then becoming mostly cloudy with scattered light rain and snow showers in the late afternoon and evening.
|
| Saturday Night |
Partly to mostly cloudy with isolated light rain and snow showers ending in the evening. |
Mt. Hood Area
| Friday |
Mostly sunny. Warmer. Locally breezy E-SE winds. Increasing high clouds late in the afternoon. |
| Friday Night |
Becoming partly to mostly cloudy. Locally breezy E-SE winds. |
| Saturday |
Very light rain and snow developing in the morning and becoming mostly cloudy with scattered light rain and snow showers in the afternoon. |
| Saturday Night |
Mostly cloudy with isolated light rain and snow showers in the evening ending overnight and becoming partly cloudy. |
Issued: 2:40 PM PDT Friday, April 21, 2017
Snow/Freezing Level (ft)
| Hurricane Ridge | Mt. Baker | Washington Pass | Leavenworth | Stevens Pass | Snoqualmie Pass | Mt. Rainier, Crystal & White Pass | Mt. Hood | ||
|---|---|---|---|---|---|---|---|---|---|
| Friday Afternoon - Friday Night | Freezing Level * | 7500' | 7500' | 7000' | ' | ' | 7500' | ' | 8500' |
| Saturday | Snow Level | 5500' | 5500' | 5500' | ' | ' | 5500' | ' | 6000' |
| Saturday Night | Snow Level | 4000' | 4000' | 4000' | ' | ' | 4000' | ' | 4500' |
| Hurricane Ridge | Elevation |
|---|---|
| Friday Afternoon - Friday Night |
Freezing Level 7500' (Easterly Flow *) |
| Saturday |
Snow Level 5500' |
| Saturday Night |
Snow Level 4000' |
| Mt. Baker | Elevation |
|---|---|
| Friday Afternoon - Friday Night |
Freezing Level 7500' (Easterly Flow *) |
| Saturday |
Snow Level 5500' |
| Saturday Night |
Snow Level 4000' |
| Washington Pass | Elevation |
|---|---|
| Friday Afternoon - Friday Night |
Freezing Level 7000' (Easterly Flow *) |
| Saturday |
Snow Level 5500' |
| Saturday Night |
Snow Level 4000' |
| Leavenworth | Elevation |
|---|---|
| Friday Afternoon - Friday Night |
Freezing Level ' (Easterly Flow *) |
| Saturday |
Snow Level ' |
| Saturday Night |
Snow Level ' |
| Stevens Pass | Elevation |
|---|---|
| Friday Afternoon - Friday Night |
Freezing Level ' (Easterly Flow *) |
| Saturday |
Snow Level ' |
| Saturday Night |
Snow Level ' |
| Snoqualmie Pass | Elevation |
|---|---|
| Friday Afternoon - Friday Night |
Freezing Level 7500' (Easterly Flow *) |
| Saturday |
Snow Level 5500' |
| Saturday Night |
Snow Level 4000' |
| Mt. Rainier & Crystal | Elevation |
|---|---|
| Friday Afternoon - Friday Night |
Freezing Level ' (Easterly Flow *) |
| Saturday |
Snow Level ' |
| Saturday Night |
Snow Level ' |
| Mt. Hood | Elevation |
|---|---|
| Friday Afternoon - Friday Night |
Freezing Level 8500' (Easterly Flow *) |
| Saturday |
Snow Level 6000' |
| Saturday Night |
Snow Level 4500' |
* 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
| Friday | Friday | |
|---|---|---|
| Hurricane Ridge | LT 0.10 | LT 0.25 |
| Mt Baker Ski Area | LT 0.10 | 0 - 0.50 |
| Washington Pass | LT 0.10 | LT 0.25 |
| Stevens Pass | LT 0.10 | LT 0.25 |
| Snoqualmie Pass | LT 0.10 | LT 0.25 |
| Mission Ridge | LT 0.10 | LT 0.10 |
| Crystal Mt | LT 0.10 | LT 0.25 |
| Paradise | LT 0.10 | LT 0.25 |
| White Pass | LT 0.10 | LT 0.25 |
| Mt Hood Meadows | LT 0.10 | LT 0.10 |
| Timberline | LT 0.10 | LT 0.25 |
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: 2:40 PM PDT Friday, April 21, 2017
Free Winds at 5000' (mph)
| Hurricane Ridge | Mt. Baker | Stevens to Snoqualmie Pass | Mt. Rainier | Mt. Hood | |
|---|---|---|---|---|---|
| Friday Afternoon | SE 10 - 20 | E 5 - 15 | ESE 15 - 25 | --- - | E 15 - 25 |
| Friday Night - Saturday Morning | SE 10 - 20 | E 5 - 15 | ESE 20 - 35 | --- - | ESE 15 - 30 |
| Saturday Afternoon | SSW 15 - 25 | S 15 - 25 | SW 10 - 20 | --- - | WSW 10 - 20 |
| Saturday Night | SW 0 - 10 | S 5 - 15 | SW 0 - 10 | --- - | WSW 5 - 15 |
| Hurricane Ridge | Elevation |
|---|---|
| Friday Afternoon | SE 10 - 20 |
| Friday Night - Saturday Morning | SE 10 - 20 |
| Saturday Afternoon | SSW 15 - 25 |
| Saturday Night | SW 0 - 10 |
| Mt. Baker | Elevation |
|---|---|
| Friday Afternoon | E 5 - 15 |
| Friday Night - Saturday Morning | E 5 - 15 |
| Saturday Afternoon | S 15 - 25 |
| Saturday Night | S 5 - 15 |
| Stevens and Snoqualmie Pass | Elevation |
|---|---|
| Friday Afternoon | ESE 15 - 25 |
| Friday Night - Saturday Morning | ESE 20 - 35 |
| Saturday Afternoon | SW 10 - 20 |
| Saturday Night | SW 0 - 10 |
| Mt. Rainier | Elevation |
|---|---|
| Friday Afternoon | --- - |
| Friday Night - Saturday Morning | --- - |
| Saturday Afternoon | --- - |
| Saturday Night | --- - |
| Mt. Hood | Elevation |
|---|---|
| Friday Afternoon | E 15 - 25 |
| Friday Night - Saturday Morning | ESE 15 - 30 |
| Saturday Afternoon | WSW 10 - 20 |
| Saturday Night | WSW 5 - 15 |
| Hurricane Ridge | Direction - Speed |
|---|---|
| Friday Afternoon | SE 10 - 20 |
| Friday Night - Saturday Morning | SE 10 - 20 |
| Saturday Afternoon | SSW 15 - 25 |
| Saturday Night | SW 0 - 10 |
| Mt. Baker | Direction - Speed |
|---|---|
| Friday Afternoon | E 5 - 15 |
| Friday Night - Saturday Morning | E 5 - 15 |
| Saturday Afternoon | S 15 - 25 |
| Saturday Night | S 5 - 15 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Friday Afternoon | ESE 15 - 25 |
| Friday Night - Saturday Morning | ESE 20 - 35 |
| Saturday Afternoon | SW 10 - 20 |
| Saturday Night | SW 0 - 10 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Friday Afternoon | --- - |
| Friday Night - Saturday Morning | --- - |
| Saturday Afternoon | --- - |
| Saturday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| Friday Afternoon | E 15 - 25 |
| Friday Night - Saturday Morning | ESE 15 - 30 |
| Saturday Afternoon | WSW 10 - 20 |
| Saturday Night | WSW 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 | SE 5 - 15 | SE 5 - 15 | SE 20 - 30 | --- - | S 10 - 20 |
| Friday Night - Saturday Morning | S 10 - 20 | S 15 - 25 | S 20 - 30 | --- - | S 15 - 25 |
| Saturday Afternoon | SW 25 - 35 | SW 15 - 25 | SW 20 - 30 | --- - | SW 25 - 35 |
| Saturday Night | SW 5 - 15 | WSW 5 - 15 | WSW 10 - 20 | --- - | SW 15 - 25 |
| Mt. Baker | Direction - Speed |
|---|---|
| Friday Afternoon | SE 5 - 15 |
| Friday Night - Saturday Morning | S 10 - 20 |
| Saturday Afternoon | SW 25 - 35 |
| Saturday Night | SW 5 - 15 |
| Washington Pass | Direction - Speed |
|---|---|
| Friday Afternoon | SE 5 - 15 |
| Friday Night - Saturday Morning | S 15 - 25 |
| Saturday Afternoon | SW 15 - 25 |
| Saturday Night | WSW 5 - 15 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Friday Afternoon | SE 20 - 30 |
| Friday Night - Saturday Morning | S 20 - 30 |
| Saturday Afternoon | SW 20 - 30 |
| Saturday Night | WSW 10 - 20 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Friday Afternoon | --- - |
| Friday Night - Saturday Morning | --- - |
| Saturday Afternoon | --- - |
| Saturday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| Friday Afternoon | S 10 - 20 |
| Friday Night - Saturday Morning | S 15 - 25 |
| Saturday Afternoon | SW 25 - 35 |
| Saturday Night | SW 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.
Issued: 2:40 PM PDT Friday, April 21, 2017
Extended Weather Synopsis for Friday night through Friday
The trailing upper level trough will open up and position itself off of Vancouver Island Sunday. An upper level shortwave rotating from the upper low should help increase shower activity and cloudiness on Sunday afternoon, especially along the west slopes of Cascades, Olympics and Mt. Hood. From there a winter-like westerly jet aimed into southern Oregon/northern California will direct a series of weather systems into the area through much of next week. The heaviest precipitation looks to be centered on the southern Washington Cascades and Mt. Hood through Tuesday, but there will be periods of moderate precipitation for all areas as the quasi-stationary upper low off of Vancouver Island ejects inland. Summing up the whole work week, it looks like a good week for accumulating snowfall in the alpine and a poor week for sunglasses.
Extended Weather
Olympics, Washington Cascades and Mt. Hood
Mostly cloudy with scattered light rain and snow showers in the morning. Becoming cloudy with light to occasionally moderate rain and snow showers in the afternoon.
Mostly cloudy with scattered light rain and snow showers.
Light to moderate rain and snow over the Olympics spreading inland to Mt. Hood, and the south and central Washington Cascades. Light rain and snow north Cascades.
Light to moderate rain and snow, stormy at times.
Extended Snow/Freezing Levels
| Mt. Baker | Snoqualmie Pass | Mt. Hood | Easterly Flow * | ||
|---|---|---|---|---|---|
| Sunday | Snow Level | 4500' - 5500' | 4500' - 5500' | 4500' - 5500' | |
| Sunday Night | Snow Level | 3500' - 4500' | 3500' - 4500' | 3500' - 4500' | |
| Monday | Snow Level | 4500' - 5500' | 4500' - 5500' | 4500' - 5500' | |
| Monday Night | Snow Level | 4000' - 5000' | 4000' - 5000' | 4000' - 5000' | |
| Tuesday | Snow Level | 5000' - 6000' | 5000' - 6000' | 5000' - 6000' |
| Mt. Baker | Elevation |
|---|---|
| Sunday |
Snow Level 4500' - 5500' |
| Sunday Night |
Snow Level 3500' - 4500' |
| Monday |
Snow Level 4500' - 5500' |
| Monday Night |
Snow Level 4000' - 5000' |
| Tuesday |
Snow Level 5000' - 6000' |
| Snoqualmie Pass | Elevation |
|---|---|
| Sunday |
Snow Level 4500' - 5500' |
| Sunday Night |
Snow Level 3500' - 4500' |
| Monday |
Snow Level 4500' - 5500' |
| Monday Night |
Snow Level 4000' - 5000' |
| Tuesday |
Snow Level 5000' - 6000' |
| Mt. Hood | Elevation |
|---|---|
| Sunday |
Snow Level 4500' - 5500' |
| Sunday Night |
Snow Level 3500' - 4500' |
| Monday |
Snow Level 4500' - 5500' |
| Monday Night |
Snow Level 4000' - 5000' |
| Tuesday |
Snow Level 5000' - 6000' |
* 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 21, 2017
The NWAC program is administered by the USDA-Forest Service and operates from the National Weather Service Forecast Office in Seattle. NWAC services are made possible by important collaboration and support from a wide variety of federal, state and private cooperators.