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
A brief, strong SW flow will carry a moderately deepening surface low across Cape Flattery, by around 4PM. A strong cold front will accompany the surface low and will cross the Northwest during the early evening hours. Generally increasingly strong S or SE winds ahead of the front will shift to W-SW behind the front and become stronger. Temperatures will drop sharply in all areas behind the front as most areas turn back to snow overnight Friday.
On Saturday, a moderate ridge and drier airmass begins moving over the US coastal waters.
Weather Forecast
Olympics
| Friday | Increasing light to moderate rain and snow. Strong crest-level wind. |
| Friday Night | Decreasing light rain and snow showers with strong W-SW winds and rapidly dropping temperatures. |
| Saturday | Light snow showers ending in the morning, with clouds in the afternoon. Decreasing westerly winds. |
| Saturday Night | Becoming mostly clear. |
Washington Cascades near and west of the Crest including Stevens, Snoqualmie and White Passes
| Friday | Increasing moderate to heavy rain and snow accompanied by strong crest-level wind. |
| Friday Night | Decreasing moderate rain and snow showers in the evening, becoming light to moderate snow showers after midnight, heaviest in the mountain loop area. Strong W-SW winds. |
| Saturday | Decreasing light to moderate snow showers in the morning becoming isolated, light snow showers in the afternoon. |
| Saturday Night | Decreasing clouds. |
East Slopes of the Washington Cascades
| Friday | Increasing moderate to heavy rain and snow accompanied by strong crest-level wind. |
| Friday Night | Decreasing moderate rain and snow showers in the evening, becoming light to moderate snow showers after midnight, heaviest at higher elevations. Strong W-SW winds. |
| Saturday | Decreasing light to moderate snow showers at higher elevations in the morning becoming isolated, light snow showers at higher elevations in the afternoon. |
| Saturday Night | Becoming clear. |
Mt. Hood
| Friday | Decreasing light rain and high elevation snow in the morning. Increasing moderate to heavy rain and high elevation snow in the afternoon. Very strong crest-level winds. |
| Friday Night | Heavy rain and high elevation snow in the evening trending to light rain and snow showers after midnight. Strong W-SW crest level winds. |
| Saturday | Decreasing light snow showers in the morning. |
| Saturday Night | Decreasing clouds in the afternoon. |
Issued: 1:51 PM PST Friday, December 29, 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 | Snow Level * | 7000' | 5000' | 3000' | ' | ' | 6500' | ' | 7500' |
| Friday Night | Snow Level | 2500' | 2500' | 4000' | ' | ' | 3000' | ' | 4500' |
| Saturday Morning | Snow Level | 2000' | 1000' | 1000' | ' | ' | 2000' | ' | 2500' |
| Saturday Afternoon | Snow Level | 2000' | 1000' | 1000' | ' | ' | 2000' | ' | 3000' |
| Saturday Night | Snow Level * | 3000' | 2000' | 2500' | ' | ' | 3000' | ' | 4500' |
| Hurricane Ridge | Elevation |
|---|---|
| Friday Afternoon |
Snow Level 7000' (Easterly Flow *) |
| Friday Night |
Snow Level 2500' |
| Saturday Morning |
Snow Level 2000' |
| Saturday Afternoon |
Snow Level 2000' |
| Saturday Night |
Snow Level 3000' (Easterly Flow *) |
| Mt. Baker | Elevation |
|---|---|
| Friday Afternoon |
Snow Level 5000' (Easterly Flow *) |
| Friday Night |
Snow Level 2500' |
| Saturday Morning |
Snow Level 1000' |
| Saturday Afternoon |
Snow Level 1000' |
| Saturday Night |
Snow Level 2000' (Easterly Flow *) |
| Washington Pass | Elevation |
|---|---|
| Friday Afternoon |
Snow Level 3000' (Easterly Flow *) |
| Friday Night |
Snow Level 4000' |
| Saturday Morning |
Snow Level 1000' |
| Saturday Afternoon |
Snow Level 1000' |
| Saturday Night |
Snow Level 2500' (Easterly Flow *) |
| Leavenworth | Elevation |
|---|---|
| Friday Afternoon |
Snow Level ' (Easterly Flow *) |
| Friday Night |
Snow Level ' |
| Saturday Morning |
Snow Level ' |
| Saturday Afternoon |
Snow Level ' |
| Saturday Night |
Snow Level ' (Easterly Flow *) |
| Stevens Pass | Elevation |
|---|---|
| Friday Afternoon |
Snow Level ' (Easterly Flow *) |
| Friday Night |
Snow Level ' |
| Saturday Morning |
Snow Level ' |
| Saturday Afternoon |
Snow Level ' |
| Saturday Night |
Snow Level ' (Easterly Flow *) |
| Snoqualmie Pass | Elevation |
|---|---|
| Friday Afternoon |
Snow Level 6500' (Easterly Flow *) |
| Friday Night |
Snow Level 3000' |
| Saturday Morning |
Snow Level 2000' |
| Saturday Afternoon |
Snow Level 2000' |
| Saturday Night |
Snow Level 3000' (Easterly Flow *) |
| Mt. Rainier & Crystal | Elevation |
|---|---|
| Friday Afternoon |
Snow Level ' (Easterly Flow *) |
| Friday Night |
Snow Level ' |
| Saturday Morning |
Snow Level ' |
| Saturday Afternoon |
Snow Level ' |
| Saturday Night |
Snow Level ' (Easterly Flow *) |
| Mt. Hood | Elevation |
|---|---|
| Friday Afternoon |
Snow Level 7500' (Easterly Flow *) |
| Friday Night |
Snow Level 4500' |
| Saturday Morning |
Snow Level 2500' |
| Saturday Afternoon |
Snow Level 3000' |
| Saturday Night |
Snow Level 4500' (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.
Precipitation Forecast
| Thursday | Thursday | |
|---|---|---|
| Hurricane Ridge | 1.00 - 1.50 | LT 0.10 |
| Mt Baker Ski Area | 0 - 1.50 | 0.25 - 0.50 |
| Washington Pass | 0 - 1.50 | LT 0.25 |
| Stevens Pass | 1.50 - 2.00 | 0.25 - 0.50 |
| Snoqualmie Pass | 2.00 - 2.50 | 0.25 - 0.50 |
| Mission Ridge | 0 - 1.00 | LT 0.25 |
| Crystal Mt | 1.50 - 2.00 | LT 0.25 |
| Paradise | 3.00 - 4.00 | 0.25 - 0.50 |
| White Pass | 1.50 - 2.00 | LT 0.25 |
| Mt Hood Meadows | 0 - 1.00 | LT 0.10 |
| Timberline | 1.00 - 1.50 | 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: 1:51 PM PST Friday, December 29, 2017
Free Winds at 5000' (mph)
| Hurricane Ridge | Mt. Baker | Stevens to Snoqualmie Pass | Mt. Rainier | Mt. Hood | |
|---|---|---|---|---|---|
| Friday Afternoon | S 25 - 35 | ESE 20 - 30 | SSE 25 - 35 | --- - | SSW 45 - 65 |
| Friday Night | WSW 30 - 40 | SW 25 - 35 | SW 40 - 60 | --- - | WSW 40 - 60 |
| Saturday Morning | W 20 - 30 | W 20 - 30 | W 20 - 30 | --- - | WSW 20 - 30 |
| Saturday Afternoon | W 10 - 20 | W 5 - 15 | W 10 - 20 | --- - | W 10 - 20 |
| Saturday Night | VAR 0 - 10 | VAR 0 - 10 | VAR 0 - 10 | --- - | E 0 - 10 |
| Hurricane Ridge | Elevation |
|---|---|
| Friday Afternoon | S 25 - 35 |
| Friday Night | WSW 30 - 40 |
| Saturday Morning | W 20 - 30 |
| Saturday Afternoon | W 10 - 20 |
| Saturday Night | VAR 0 - 10 |
| Mt. Baker | Elevation |
|---|---|
| Friday Afternoon | ESE 20 - 30 |
| Friday Night | SW 25 - 35 |
| Saturday Morning | W 20 - 30 |
| Saturday Afternoon | W 5 - 15 |
| Saturday Night | VAR 0 - 10 |
| Stevens and Snoqualmie Pass | Elevation |
|---|---|
| Friday Afternoon | SSE 25 - 35 |
| Friday Night | SW 40 - 60 |
| Saturday Morning | W 20 - 30 |
| Saturday Afternoon | W 10 - 20 |
| Saturday Night | VAR 0 - 10 |
| Mt. Rainier | Elevation |
|---|---|
| Friday Afternoon | --- - |
| Friday Night | --- - |
| Saturday Morning | --- - |
| Saturday Afternoon | --- - |
| Saturday Night | --- - |
| Mt. Hood | Elevation |
|---|---|
| Friday Afternoon | SSW 45 - 65 |
| Friday Night | WSW 40 - 60 |
| Saturday Morning | WSW 20 - 30 |
| Saturday Afternoon | W 10 - 20 |
| Saturday Night | E 0 - 10 |
| Hurricane Ridge | Direction - Speed |
|---|---|
| Friday Afternoon | S 25 - 35 |
| Friday Night | WSW 30 - 40 |
| Saturday Morning | W 20 - 30 |
| Saturday Afternoon | W 10 - 20 |
| Saturday Night | VAR 0 - 10 |
| Mt. Baker | Direction - Speed |
|---|---|
| Friday Afternoon | ESE 20 - 30 |
| Friday Night | SW 25 - 35 |
| Saturday Morning | W 20 - 30 |
| Saturday Afternoon | W 5 - 15 |
| Saturday Night | VAR 0 - 10 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Friday Afternoon | SSE 25 - 35 |
| Friday Night | SW 40 - 60 |
| Saturday Morning | W 20 - 30 |
| Saturday Afternoon | W 10 - 20 |
| Saturday Night | VAR 0 - 10 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Friday Afternoon | --- - |
| Friday Night | --- - |
| Saturday Morning | --- - |
| Saturday Afternoon | --- - |
| Saturday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| Friday Afternoon | SSW 45 - 65 |
| Friday Night | WSW 40 - 60 |
| Saturday Morning | WSW 20 - 30 |
| Saturday Afternoon | W 10 - 20 |
| Saturday Night | E 0 - 10 |
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 | SSW 45 - 65 | SW 40 - 60 | SW 55 - 75 | --- - | SW 60 - 80 |
| Friday Night | SW 45 - 65 | SW 50 - 70 | SW 50 - 70 | --- - | SW 50 - 70 |
| Saturday Morning | W 25 - 35 | W 35 - 50 | WNW 30 - 40 | --- - | W 30 - 40 |
| Saturday Afternoon | W 20 - 30 | W 20 - 30 | W 30 - 40 | --- - | WNW 25 - 35 |
| Saturday Night | NW 15 - 25 | W 10 - 20 | WNW 15 - 25 | --- - | WNW 10 - 20 |
| Mt. Baker | Direction - Speed |
|---|---|
| Friday Afternoon | SSW 45 - 65 |
| Friday Night | SW 45 - 65 |
| Saturday Morning | W 25 - 35 |
| Saturday Afternoon | W 20 - 30 |
| Saturday Night | NW 15 - 25 |
| Washington Pass | Direction - Speed |
|---|---|
| Friday Afternoon | SW 40 - 60 |
| Friday Night | SW 50 - 70 |
| Saturday Morning | W 35 - 50 |
| Saturday Afternoon | W 20 - 30 |
| Saturday Night | W 10 - 20 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Friday Afternoon | SW 55 - 75 |
| Friday Night | SW 50 - 70 |
| Saturday Morning | WNW 30 - 40 |
| Saturday Afternoon | W 30 - 40 |
| Saturday Night | WNW 15 - 25 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Friday Afternoon | --- - |
| Friday Night | --- - |
| Saturday Morning | --- - |
| Saturday Afternoon | --- - |
| Saturday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| Friday Afternoon | SW 60 - 80 |
| Friday Night | SW 50 - 70 |
| Saturday Morning | W 30 - 40 |
| Saturday Afternoon | WNW 25 - 35 |
| Saturday Night | WNW 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: 1:51 PM PST Friday, December 29, 2017
Extended Weather Synopsis for Thursday night through Thursday
Another upper ridge will linger off the U.S. west coast Sunday-Tuesday. This time-frame will also feature offshore surface flow.
Extended Weather
Olympics, Washington Cascades and Mt. Hood Area
Sunday Sunny. Monday Mostly fair with some mid and high clouds at times. Tuesday Mostly fair with some mid and high clouds at times.Extended Snow/Freezing Levels
| Mt. Baker | Snoqualmie Pass | Mt. Hood | Easterly Flow * | ||
|---|---|---|---|---|---|
| Sunday | Freezing Level | 4500' - 5500' | 3500' - 4500' | 10000' - 11000' | * |
| Sunday Night | Freezing Level | 7500' - 8500' | 4500' - 5500' | 9500' - 10500' | * |
| Monday | Freezing Level | 7500' - 8500' | 5000' - 6000' | 9500' - 10500' | * |
| Monday Night | Freezing Level | 6500' - 7500' | 6000' - 7000' | 9000' - 10000' | * |
| Tuesday | Freezing Level | 7000' - 9000' | 6000' - 8000' | 9000' - 11000' | * |
| Mt. Baker | Elevation |
|---|---|
| Sunday |
Freezing Level 4500' - 5500' (Easterly Flow *) |
| Sunday Night |
Freezing Level 7500' - 8500' (Easterly Flow *) |
| Monday |
Freezing Level 7500' - 8500' (Easterly Flow *) |
| Monday Night |
Freezing Level 6500' - 7500' (Easterly Flow *) |
| Tuesday |
Freezing Level 7000' - 9000' (Easterly Flow *) |
| Snoqualmie Pass | Elevation |
|---|---|
| Sunday |
Freezing Level 3500' - 4500' (Easterly Flow *) |
| Sunday Night |
Freezing Level 4500' - 5500' (Easterly Flow *) |
| Monday |
Freezing Level 5000' - 6000' (Easterly Flow *) |
| Monday Night |
Freezing Level 6000' - 7000' (Easterly Flow *) |
| Tuesday |
Freezing Level 6000' - 8000' (Easterly Flow *) |
| Mt. Hood | Elevation |
|---|---|
| Sunday |
Freezing Level 10000' - 11000' (Easterly Flow *) |
| Sunday Night |
Freezing Level 9500' - 10500' (Easterly Flow *) |
| Monday |
Freezing Level 9500' - 10500' (Easterly Flow *) |
| Monday Night |
Freezing Level 9000' - 10000' (Easterly Flow *) |
| Tuesday |
Freezing Level 9000' - 11000' (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 29, 2017
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