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 & Wednesday
The Northwest will experience a very active weather pattern Thursday and Friday with moist systems crossing the Pacific Northwest.
On Thursday, strong westerly flow over a flat ridge will carry an occluded front east and south across the NW during the daylight hours. This will bring increasing moderate crest-level winds, increasing moderate to heavy rain and snow, along with rising snow levels. Stevens Pass should remain snow during the daylight hours while Snoqualmie will continue to see see mixed precipitation or freezing rain at pass level.
The frontal zone will remain over the South Cascades and Hood zones tonight and snow levels should remain steady in most areas.
On Friday, another moist system arrives on a SW flow. This surface low will be developing arrives along with a cold front on Friday evening, tracking across NW Washington State. Crest level winds ahead of the low will be moderate to strong in the central Cascades, with strong winds in the S. Cascades and Mt. Hood areas.
A strong W-SW flow will be ushered in behind the front Friday night along with lowering snow levels and a changeover to snow at pass levels around midnight.
Weather Forecast
Olympics
| Thursday | Increasing light rain and snow. Rising snow levels. |
| Thursday Night | Occasional light rain and snow. |
| Friday | Increasing light to moderate rain and snow. |
| Friday Night | Light rain changing to snow showers. |
Washington Cascades near and west of the Crest including Stevens, Snoqualmie and White Passes
| Thursday | Increasing light to moderate rain/snow in the morning becoming moderate rain/snow in the afternoon. Freezing rain or rain at Snoqualmie. |
| Thursday Night | Light rain and snow in the north, with moderate to heavy rain/snow central and south. |
| Friday | Light to moderate rain/snow north with renewed moderate to heavy rain/snow central and south. |
| Friday Night | Decreasing light to moderate rain and snow showers. Lowering snow levels. |
East Slopes of the Washington Cascades
| Thursday | Increasing light rain/snow in the morning becoming increasing light to moderate rain/snow in the afternoon. |
| Thursday Night | Light rain/snow north, with light to moderate rain/snow central and south. |
| Friday | Light to moderate rain/snow north, with renewed moderate to heavy rain/snow central and south. |
| Friday Night | Decreasing light to moderate rain/snow showers, heaviest higher elevations. |
Mt. Hood
| Thursday | Cloudy in the morning with increasing light rain/snow in the afternoon. |
| Thursday Night | Heavy rain and snow. |
| Friday | Decreasing moderate to heavy rain/snow in the morning, with renewed heavy rain/snow in the afternoon. |
| Friday Night | Moderate to heavy rain/snow in the evening, becoming decreasing light to moderate rain/snow showers after midnight. |
Issued: 2:10 PM PST Thursday, December 28, 2017
Snow/Freezing Level (ft)
| Hurricane Ridge | Mt. Baker | Washington Pass | Leavenworth | Stevens Pass | Snoqualmie Pass | Mt. Rainier, Crystal & White Pass | Mt. Hood | ||
|---|---|---|---|---|---|---|---|---|---|
| Thursday Afternoon | Snow Level * | 4500' | 3000' | 3000' | ' | ' | 4000' | ' | 5000' |
| Thursday Night | Snow Level * | 5500' | 3500' | 3500' | ' | ' | 6500' | ' | 8000' |
| Friday Morning | Snow Level * | 5000' | 4000' | 3500' | ' | ' | 5500' | ' | 7000' |
| Friday Afternoon | Snow Level * | 6000' | 4000' | 3000' | ' | ' | 6500' | ' | 7000' |
| Friday Night | Snow Level | 2500' | 2000' | 3500' | ' | ' | 3500' | ' | 5000' |
| Hurricane Ridge | Elevation |
|---|---|
| Thursday Afternoon |
Snow Level 4500' (Easterly Flow *) |
| Thursday Night |
Snow Level 5500' (Easterly Flow *) |
| Friday Morning |
Snow Level 5000' (Easterly Flow *) |
| Friday Afternoon |
Snow Level 6000' (Easterly Flow *) |
| Friday Night |
Snow Level 2500' |
| Mt. Baker | Elevation |
|---|---|
| Thursday Afternoon |
Snow Level 3000' (Easterly Flow *) |
| Thursday Night |
Snow Level 3500' (Easterly Flow *) |
| Friday Morning |
Snow Level 4000' (Easterly Flow *) |
| Friday Afternoon |
Snow Level 4000' (Easterly Flow *) |
| Friday Night |
Snow Level 2000' |
| Washington Pass | Elevation |
|---|---|
| Thursday Afternoon |
Snow Level 3000' (Easterly Flow *) |
| Thursday Night |
Snow Level 3500' (Easterly Flow *) |
| Friday Morning |
Snow Level 3500' (Easterly Flow *) |
| Friday Afternoon |
Snow Level 3000' (Easterly Flow *) |
| Friday Night |
Snow Level 3500' |
| Leavenworth | Elevation |
|---|---|
| Thursday Afternoon |
Snow Level ' (Easterly Flow *) |
| Thursday Night |
Snow Level ' (Easterly Flow *) |
| Friday Morning |
Snow Level ' (Easterly Flow *) |
| Friday Afternoon |
Snow Level ' (Easterly Flow *) |
| Friday Night |
Snow Level ' |
| Stevens Pass | Elevation |
|---|---|
| Thursday Afternoon |
Snow Level ' (Easterly Flow *) |
| Thursday Night |
Snow Level ' (Easterly Flow *) |
| Friday Morning |
Snow Level ' (Easterly Flow *) |
| Friday Afternoon |
Snow Level ' (Easterly Flow *) |
| Friday Night |
Snow Level ' |
| Snoqualmie Pass | Elevation |
|---|---|
| Thursday Afternoon |
Snow Level 4000' (Easterly Flow *) |
| Thursday Night |
Snow Level 6500' (Easterly Flow *) |
| Friday Morning |
Snow Level 5500' (Easterly Flow *) |
| Friday Afternoon |
Snow Level 6500' (Easterly Flow *) |
| Friday Night |
Snow Level 3500' |
| Mt. Rainier & Crystal | Elevation |
|---|---|
| Thursday Afternoon |
Snow Level ' (Easterly Flow *) |
| Thursday Night |
Snow Level ' (Easterly Flow *) |
| Friday Morning |
Snow Level ' (Easterly Flow *) |
| Friday Afternoon |
Snow Level ' (Easterly Flow *) |
| Friday Night |
Snow Level ' |
| Mt. Hood | Elevation |
|---|---|
| Thursday Afternoon |
Snow Level 5000' (Easterly Flow *) |
| Thursday Night |
Snow Level 8000' (Easterly Flow *) |
| Friday Morning |
Snow Level 7000' (Easterly Flow *) |
| Friday Afternoon |
Snow Level 7000' (Easterly Flow *) |
| Friday Night |
Snow Level 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.
Precipitation Forecast
| Wednesday | Wednesday | |
|---|---|---|
| Hurricane Ridge | 0.20 - 0.50 | 0 - 1.00 |
| Mt Baker Ski Area | 0.75 - 1.00 | 1.50 - 2.00 |
| Washington Pass | 0 - 0.50 | 1.00 - 1.50 |
| Stevens Pass | 0 - 1.00 | 1.50 - 2.00 |
| Snoqualmie Pass | 0 - 1.50 | 0 - 2.00 |
| Mission Ridge | LT 0.25 | 0 - 1.00 |
| Crystal Mt | 0 - 1.00 | 0 - 1.50 |
| Paradise | 0 - 3.00 | 0 - 3.00 |
| White Pass | 1.50 - 2.00 | 0 - 2.00 |
| Mt Hood Meadows | 2.00 - 3.00 | 1.00 - 1.50 |
| Timberline | 0 - 3.00 | 0 - 1.50 |
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: 2:10 PM PST Thursday, December 28, 2017
Free Winds at 5000' (mph)
| Hurricane Ridge | Mt. Baker | Stevens to Snoqualmie Pass | Mt. Rainier | Mt. Hood | |
|---|---|---|---|---|---|
| Thursday Afternoon | SW 20 - 30 | S 20 - 30 | SSW 20 - 30 | --- - | SW 30 - 40 |
| Thursday Night | SW 5 - 15 | N 0 - 10 | SW 15 - 25 | --- - | SW 40 - 60 |
| Friday Morning | SE 15 - 25 | ESE 5 - 15 | S 20 - 30 | --- - | SW 40 - 60 |
| Friday Afternoon | SSW 15 - 25 | ESE 15 - 25 | S 25 - 35 | --- - | SW 40 - 60 |
| Friday Night | WSW 25 - 35 | WSW 20 - 30 | SSW 30 - 40 | --- - | WSW 40 - 60 |
| Hurricane Ridge | Elevation |
|---|---|
| Thursday Afternoon | SW 20 - 30 |
| Thursday Night | SW 5 - 15 |
| Friday Morning | SE 15 - 25 |
| Friday Afternoon | SSW 15 - 25 |
| Friday Night | WSW 25 - 35 |
| Mt. Baker | Elevation |
|---|---|
| Thursday Afternoon | S 20 - 30 |
| Thursday Night | N 0 - 10 |
| Friday Morning | ESE 5 - 15 |
| Friday Afternoon | ESE 15 - 25 |
| Friday Night | WSW 20 - 30 |
| Stevens and Snoqualmie Pass | Elevation |
|---|---|
| Thursday Afternoon | SSW 20 - 30 |
| Thursday Night | SW 15 - 25 |
| Friday Morning | S 20 - 30 |
| Friday Afternoon | S 25 - 35 |
| Friday Night | SSW 30 - 40 |
| Mt. Rainier | Elevation |
|---|---|
| Thursday Afternoon | --- - |
| Thursday Night | --- - |
| Friday Morning | --- - |
| Friday Afternoon | --- - |
| Friday Night | --- - |
| Mt. Hood | Elevation |
|---|---|
| Thursday Afternoon | SW 30 - 40 |
| Thursday Night | SW 40 - 60 |
| Friday Morning | SW 40 - 60 |
| Friday Afternoon | SW 40 - 60 |
| Friday Night | WSW 40 - 60 |
| Hurricane Ridge | Direction - Speed |
|---|---|
| Thursday Afternoon | SW 20 - 30 |
| Thursday Night | SW 5 - 15 |
| Friday Morning | SE 15 - 25 |
| Friday Afternoon | SSW 15 - 25 |
| Friday Night | WSW 25 - 35 |
| Mt. Baker | Direction - Speed |
|---|---|
| Thursday Afternoon | S 20 - 30 |
| Thursday Night | N 0 - 10 |
| Friday Morning | ESE 5 - 15 |
| Friday Afternoon | ESE 15 - 25 |
| Friday Night | WSW 20 - 30 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Thursday Afternoon | SSW 20 - 30 |
| Thursday Night | SW 15 - 25 |
| Friday Morning | S 20 - 30 |
| Friday Afternoon | S 25 - 35 |
| Friday Night | SSW 30 - 40 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Thursday Afternoon | --- - |
| Thursday Night | --- - |
| Friday Morning | --- - |
| Friday Afternoon | --- - |
| Friday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| Thursday Afternoon | SW 30 - 40 |
| Thursday Night | SW 40 - 60 |
| Friday Morning | SW 40 - 60 |
| Friday Afternoon | SW 40 - 60 |
| Friday Night | WSW 40 - 60 |
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 Morning | WSW 30 - 40 | WSW 30 - 40 | WSW 30 - 40 | --- - | WSW 45 - 65 |
| Thursday Afternoon | SW 35 - 50 | SW 35 - 50 | SW 40 - 60 | --- - | WSW 70 - 90 |
| Thursday Night | WSW 25 - 35 | WSW 30 - 40 | WSW 30 - 50 | --- - | WSW 50 - 80 |
| Friday Morning | S 15 - 25 | SSW 15 - 25 | SW 40 - 60 | --- - | SW 55 - 75 |
| Friday Afternoon | SW 35 - 50 | SW 30 - 40 | SW 55 - 75 | --- - | WSW 55 - 75 |
| Friday Night | WSW 40 - 60 | WSW 50 - 70 | WSW 45 - 65 | --- - | WSW 50 - 70 |
| Mt. Baker | Direction - Speed |
|---|---|
| Thursday Morning | WSW 30 - 40 |
| Thursday Afternoon | SW 35 - 50 |
| Thursday Night | WSW 25 - 35 |
| Friday Morning | S 15 - 25 |
| Friday Afternoon | SW 35 - 50 |
| Friday Night | WSW 40 - 60 |
| Washington Pass | Direction - Speed |
|---|---|
| Thursday Morning | WSW 30 - 40 |
| Thursday Afternoon | SW 35 - 50 |
| Thursday Night | WSW 30 - 40 |
| Friday Morning | SSW 15 - 25 |
| Friday Afternoon | SW 30 - 40 |
| Friday Night | WSW 50 - 70 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Thursday Morning | WSW 30 - 40 |
| Thursday Afternoon | SW 40 - 60 |
| Thursday Night | WSW 30 - 50 |
| Friday Morning | SW 40 - 60 |
| Friday Afternoon | SW 55 - 75 |
| Friday Night | WSW 45 - 65 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Thursday Morning | --- - |
| Thursday Afternoon | --- - |
| Thursday Night | --- - |
| Friday Morning | --- - |
| Friday Afternoon | --- - |
| Friday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| Thursday Morning | WSW 45 - 65 |
| Thursday Afternoon | WSW 70 - 90 |
| Thursday Night | WSW 50 - 80 |
| Friday Morning | SW 55 - 75 |
| Friday Afternoon | WSW 55 - 75 |
| Friday Night | WSW 50 - 70 |
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: 2:10 PM PST Thursday, December 28, 2017
Extended Weather Synopsis for Wednesday night through Wednesday
Quite a change will be seen in the Saturday through Monday time period with an upper ridge lingering over the Northwest coastal waters.
Extended Weather
Olympics, Washington Cascades and Mt. Hood Area
Extended Snow/Freezing Levels
| Mt. Baker | Snoqualmie Pass | Mt. Hood | Easterly Flow * | ||
|---|---|---|---|---|---|
| Saturday | Snow Level | 1000' - 2000' | 1500' - 2500' | 2500' - 3500' | |
| Saturday Night | Freezing Level | 1000' - 2000' | 500' - 1500' | 2500' - 3500' | |
| Sunday | Freezing Level | 3000' - 4000' | 3000' - 4000' | 6000' - 7000' | * |
| Sunday Night | Freezing Level | 0' - 2000' | 0' - 2000' | 1500' - 3500' | * |
| Monday | Freezing Level | 3000' - 5000' | 3000' - 5000' | 3000' - 5000' | * |
| Mt. Baker | Elevation |
|---|---|
| Saturday |
Snow Level 1000' - 2000' |
| Saturday Night |
Freezing Level 1000' - 2000' |
| Sunday |
Freezing Level 3000' - 4000' (Easterly Flow *) |
| Sunday Night |
Freezing Level 0' - 2000' (Easterly Flow *) |
| Monday |
Freezing Level 3000' - 5000' (Easterly Flow *) |
| Snoqualmie Pass | Elevation |
|---|---|
| Saturday |
Snow Level 1500' - 2500' |
| Saturday Night |
Freezing Level 500' - 1500' |
| Sunday |
Freezing Level 3000' - 4000' (Easterly Flow *) |
| Sunday Night |
Freezing Level 0' - 2000' (Easterly Flow *) |
| Monday |
Freezing Level 3000' - 5000' (Easterly Flow *) |
| Mt. Hood | Elevation |
|---|---|
| Saturday |
Snow Level 2500' - 3500' |
| Saturday Night |
Freezing Level 2500' - 3500' |
| Sunday |
Freezing Level 6000' - 7000' (Easterly Flow *) |
| Sunday Night |
Freezing Level 1500' - 3500' (Easterly Flow *) |
| Monday |
Freezing Level 3000' - 5000' (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 28, 2017
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