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 & Sunday
A cold upper level low positioned along the west coast of British Columbia will rotate two troughs through the region over the next 24 hours. The first one will lift through this afternoon, somewhat invigorating showers in the afternoon. The second one will pass through tonight with light additional snowfall continuing, especially along the west slopes of the Cascades and Mt. Hood. Some of the coldest air seen in some time will keep snow levels low throughout the short term.
The flow aloft will become zonal (westerly) on Friday as orographic showers take over and continue to favor the west slopes of the Cascades. Crest-level westerlies will stay moderate from this afternoon through Friday night. A fast moving low pressure system will approach the Pacific Northwest Friday night, with showers seamlessly transitioning to steady snow and becoming moderate for Mt. Hood and the south and central Cascades after midnight.
Weather Forecast
Olympics
| Thursday | Cloudy with light snow showers becoming scattered in the afternoon. |
| Thursday Night | Light snow showers. |
| Friday | Light snow showers. |
| Friday Night | Light snow showers becoming light to moderate snow after midnight. |
Washington Cascades near and west of the Crest including Stevens, Snoqualmie and White Passes
| Thursday | Increasing clouds during the day. Isolated snow showers in the morning becoming widespread light snow showers in the afternoon. |
| Thursday Night | Light to occasionally moderate snow showers. Moderate crest level winds mainly central and south Cascades. |
| Friday | Light to occasionally moderate snow showers. Moderate crest level winds mainly central and south Cascades. |
| Friday Night | Light snow showers becoming light snow after midnight, except moderate Snoqualmie Pass and south. Moderate crest level winds. |
East Slopes of the Washington Cascades
| Thursday | Partly cloudy in the morning becoming mostly cloudy in the afternoon. Isolated snow showers in the morning becoming scattered light snow showers in the afternoon. |
| Thursday Night | Light snow showers with decreasing clouds and shower activity further east of the crest. Moderate crest level winds. |
| Friday | Light snow showers with decreasing clouds and shower activity further east of the crest. Moderate crest level winds. |
| Friday Night | Light snow showers becoming light snow after midnight central-east and southeast Cascades. Moderate crest level winds. |
Mt. Hood
| Thursday | Cloudy with scattered light snow showers in the morning increasing in the afternoon. |
| Thursday Night | Light to moderate snow showers. Moderate alpine winds. |
| Friday | Light to moderate snow showers. Moderate alpine winds. |
| Friday Night | Light to moderate snow showers becoming moderate snow after midnight. Moderate alpine winds increasing after midnight. |
Issued: 2:38 PM PST Thursday, January 25, 2018
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 | 1500' | 1000' | 1000' | ' | ' | 1500' | ' | 2000' |
| Thursday Night | Snow Level | 500' | 500' | 0' | ' | ' | 500' | ' | 1500' |
| Friday Morning | Snow Level | 500' | 500' | 0' | ' | ' | 500' | ' | 1500' |
| Friday Afternoon | Snow Level | 1500' | 1000' | 1000' | ' | ' | 1500' | ' | 2500' |
| Friday Night | Snow Level * | 3000' | 1500' | 1000' | ' | ' | 1500' | ' | 2500' |
| Hurricane Ridge | Elevation |
|---|---|
| Thursday Afternoon |
Snow Level 1500' |
| Thursday Night |
Snow Level 500' |
| Friday Morning |
Snow Level 500' |
| Friday Afternoon |
Snow Level 1500' |
| Friday Night |
Snow Level 3000' (Easterly Flow *) |
| Mt. Baker | Elevation |
|---|---|
| Thursday Afternoon |
Snow Level 1000' |
| Thursday Night |
Snow Level 500' |
| Friday Morning |
Snow Level 500' |
| Friday Afternoon |
Snow Level 1000' |
| Friday Night |
Snow Level 1500' (Easterly Flow *) |
| Washington Pass | Elevation |
|---|---|
| Thursday Afternoon |
Snow Level 1000' |
| Thursday Night |
Snow Level 0' |
| Friday Morning |
Snow Level 0' |
| Friday Afternoon |
Snow Level 1000' |
| Friday Night |
Snow Level 1000' (Easterly Flow *) |
| Leavenworth | Elevation |
|---|---|
| Thursday Afternoon |
Snow Level ' |
| Thursday Night |
Snow Level ' |
| Friday Morning |
Snow Level ' |
| Friday Afternoon |
Snow Level ' |
| Friday Night |
Snow Level ' (Easterly Flow *) |
| Stevens Pass | Elevation |
|---|---|
| Thursday Afternoon |
Snow Level ' |
| Thursday Night |
Snow Level ' |
| Friday Morning |
Snow Level ' |
| Friday Afternoon |
Snow Level ' |
| Friday Night |
Snow Level ' (Easterly Flow *) |
| Snoqualmie Pass | Elevation |
|---|---|
| Thursday Afternoon |
Snow Level 1500' |
| Thursday Night |
Snow Level 500' |
| Friday Morning |
Snow Level 500' |
| Friday Afternoon |
Snow Level 1500' |
| Friday Night |
Snow Level 1500' (Easterly Flow *) |
| Mt. Rainier & Crystal | Elevation |
|---|---|
| Thursday Afternoon |
Snow Level ' |
| Thursday Night |
Snow Level ' |
| Friday Morning |
Snow Level ' |
| Friday Afternoon |
Snow Level ' |
| Friday Night |
Snow Level ' (Easterly Flow *) |
| Mt. Hood | Elevation |
|---|---|
| Thursday Afternoon |
Snow Level 2000' |
| Thursday Night |
Snow Level 1500' |
| Friday Morning |
Snow Level 1500' |
| Friday Afternoon |
Snow Level 2500' |
| Friday Night |
Snow Level 2500' (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
| Sunday | Sunday | |
|---|---|---|
| Hurricane Ridge | 0.25 - 0.50 | 0 - 0.50 |
| Mt Baker Ski Area | 0.50 - 0.75 | 0 - 0.50 |
| Washington Pass | LT 0.25 | LT 0.25 |
| Stevens Pass | LT 0.25 | 0.50 - 0.75 |
| Snoqualmie Pass | 0 - 0.50 | 0 - 1.00 |
| Mission Ridge | LT 0.10 | 0.25 - 0.50 |
| Crystal Mt | LT 0.25 | 0.75 - 1.00 |
| Paradise | 0.50 - 0.75 | 0 - 1.50 |
| White Pass | 0.25 - 0.50 | 0.75 - 1.00 |
| Mt Hood Meadows | 0 - 1.00 | 1.00 - 1.50 |
| Timberline | 1.00 - 1.50 | 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: 2:38 PM PST Thursday, January 25, 2018
Free Winds at 5000' (mph)
| Hurricane Ridge | Mt. Baker | Stevens to Snoqualmie Pass | Mt. Rainier | Mt. Hood | |
|---|---|---|---|---|---|
| Thursday Afternoon | SW 10 - 20 | S 5 - 15 | SW 15 - 25 | --- - | SW 15 - 25 |
| Thursday Night | SW 10 - 20 | S 5 - 15 | SW 15 - 25 | --- - | SW 15 - 25 |
| Friday Morning | SW 15 - 25 | SW 10 - 20 | SW 15 - 30 | --- - | SW 20 - 30 |
| Friday Afternoon | SW 10 - 20 | SW 5 - 15 | SW 15 - 30 | --- - | SW 15 - 25 |
| Friday Night | SE 15 - 25 | SE 5 - 15 | SE 10 - 20 | --- - | SW 15 - 25 |
| Hurricane Ridge | Elevation |
|---|---|
| Thursday Afternoon | SW 10 - 20 |
| Thursday Night | SW 10 - 20 |
| Friday Morning | SW 15 - 25 |
| Friday Afternoon | SW 10 - 20 |
| Friday Night | SE 15 - 25 |
| Mt. Baker | Elevation |
|---|---|
| Thursday Afternoon | S 5 - 15 |
| Thursday Night | S 5 - 15 |
| Friday Morning | SW 10 - 20 |
| Friday Afternoon | SW 5 - 15 |
| Friday Night | SE 5 - 15 |
| Stevens and Snoqualmie Pass | Elevation |
|---|---|
| Thursday Afternoon | SW 15 - 25 |
| Thursday Night | SW 15 - 25 |
| Friday Morning | SW 15 - 30 |
| Friday Afternoon | SW 15 - 30 |
| Friday Night | SE 10 - 20 |
| Mt. Rainier | Elevation |
|---|---|
| Thursday Afternoon | --- - |
| Thursday Night | --- - |
| Friday Morning | --- - |
| Friday Afternoon | --- - |
| Friday Night | --- - |
| Mt. Hood | Elevation |
|---|---|
| Thursday Afternoon | SW 15 - 25 |
| Thursday Night | SW 15 - 25 |
| Friday Morning | SW 20 - 30 |
| Friday Afternoon | SW 15 - 25 |
| Friday Night | SW 15 - 25 |
| Hurricane Ridge | Direction - Speed |
|---|---|
| Thursday Afternoon | SW 10 - 20 |
| Thursday Night | SW 10 - 20 |
| Friday Morning | SW 15 - 25 |
| Friday Afternoon | SW 10 - 20 |
| Friday Night | SE 15 - 25 |
| Mt. Baker | Direction - Speed |
|---|---|
| Thursday Afternoon | S 5 - 15 |
| Thursday Night | S 5 - 15 |
| Friday Morning | SW 10 - 20 |
| Friday Afternoon | SW 5 - 15 |
| Friday Night | SE 5 - 15 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Thursday Afternoon | SW 15 - 25 |
| Thursday Night | SW 15 - 25 |
| Friday Morning | SW 15 - 30 |
| Friday Afternoon | SW 15 - 30 |
| Friday Night | SE 10 - 20 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Thursday Afternoon | --- - |
| Thursday Night | --- - |
| Friday Morning | --- - |
| Friday Afternoon | --- - |
| Friday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| Thursday Afternoon | SW 15 - 25 |
| Thursday Night | SW 15 - 25 |
| Friday Morning | SW 20 - 30 |
| Friday Afternoon | SW 15 - 25 |
| Friday 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.
Free Winds at 9000' (mph)
| Mt. Baker | Washington Pass | Stevens to Snoqualmie Pass | Mt. Rainier | Mt. Hood | |
|---|---|---|---|---|---|
| Thursday Afternoon | SW 15 - 25 | SW 10 - 20 | WSW 30 - 40 | --- - | SW 30 - 40 |
| Thursday Night | SW 15 - 25 | WSW 15 - 25 | WSW 30 - 40 | --- - | WSW 35 - 45 |
| Friday Morning | SW 20 - 30 | SW 25 - 35 | WSW 30 - 40 | --- - | WSW 35 - 45 |
| Friday Afternoon | SW 20 - 30 | WSW 25 - 35 | WSW 30 - 40 | --- - | SW 30 - 40 |
| Friday Night | SW 25 - 35 | S 15 - 25 | SW 30 - 40 | --- - | SW 35 - 50 |
| Mt. Baker | Direction - Speed |
|---|---|
| Thursday Afternoon | SW 15 - 25 |
| Thursday Night | SW 15 - 25 |
| Friday Morning | SW 20 - 30 |
| Friday Afternoon | SW 20 - 30 |
| Friday Night | SW 25 - 35 |
| Washington Pass | Direction - Speed |
|---|---|
| Thursday Afternoon | SW 10 - 20 |
| Thursday Night | WSW 15 - 25 |
| Friday Morning | SW 25 - 35 |
| Friday Afternoon | WSW 25 - 35 |
| Friday Night | S 15 - 25 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Thursday Afternoon | WSW 30 - 40 |
| Thursday Night | WSW 30 - 40 |
| Friday Morning | WSW 30 - 40 |
| Friday Afternoon | WSW 30 - 40 |
| Friday Night | SW 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 | WSW 35 - 45 |
| Friday Morning | WSW 35 - 45 |
| Friday Afternoon | SW 30 - 40 |
| Friday Night | SW 35 - 50 |
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: 2:38 PM PST Thursday, January 25, 2018
Extended Weather Synopsis for Sunday night through Sunday
An occluded front will rapidly pass through the Cascades late Saturday morning. A burst of moderate snow, heaviest from Snoqualmie Pass and south in the morning will transition to rain and snow showers with gusty post-frontal westerly winds in the afternoon. After a cold start to the storm, a sharp warming trend should occur after the frontal passage with a switch from east to west winds in the Passes.
Warm frontal moisture from a developing atmospheric river with a subtropical moisture tap should renew moderate precipitation Saturday night, as the warm front lifts from northern Oregon and into Washington overnight. The axis of heaviest precipitation will lift into southern British Columbia during the day on Sunday with a clearing trend in the south Washington Cascades and Mt. Hood possible later in the day. Snow levels will rise rapidly on Sunday as the boundary pushes north into the 6000-7000 ft range.
The atmospheric river looks to hang up over southern B.C. Sunday night before the frontal boundary begins to slowly sag south during the day on Monday with another potential shot of moderate to heavy precipitation and a slow cooling trend.
Extended Weather
Olympics, Washington Cascades and Mt. Hood Area
Extended Snow/Freezing Levels
| Mt. Baker | Snoqualmie Pass | Mt. Hood | Easterly Flow * | ||
|---|---|---|---|---|---|
| Saturday Morning | Snow Level | 1000' - 2000' | 1500' - 2500' | 4000' - 5000' | * |
| Saturday Night | Snow Level | 3000' - 4000' | 4000' - 5000' | 6500' - 7500' | |
| Sunday | Snow Level | 5500' - 6500' | 5500' - 6500' | 7000' - 8000' | |
| Sunday Night | Snow Level | 5500' - 6500' | 5500' - 6500' | 7000' - 8000' | |
| Monday | Snow Level | 4000' - 5000' | 4000' - 5000' | 5500' - 6500' | |
| Saturday Afternoon | Snow Level | 3000' - 4000' | 3500' - 4500' | 5500' - 6500' |
| Mt. Baker | Elevation |
|---|---|
| Saturday Morning |
Snow Level 1000' - 2000' (Easterly Flow *) |
| Saturday Night |
Snow Level 3000' - 4000' |
| Sunday |
Snow Level 5500' - 6500' |
| Sunday Night |
Snow Level 5500' - 6500' |
| Monday |
Snow Level 4000' - 5000' |
| Saturday Afternoon |
Snow Level 3000' - 4000' |
| Snoqualmie Pass | Elevation |
|---|---|
| Saturday Morning |
Snow Level 1500' - 2500' (Easterly Flow *) |
| Saturday Night |
Snow Level 4000' - 5000' |
| Sunday |
Snow Level 5500' - 6500' |
| Sunday Night |
Snow Level 5500' - 6500' |
| Monday |
Snow Level 4000' - 5000' |
| Saturday Afternoon |
Snow Level 3500' - 4500' |
| Mt. Hood | Elevation |
|---|---|
| Saturday Morning |
Snow Level 4000' - 5000' (Easterly Flow *) |
| Saturday Night |
Snow Level 6500' - 7500' |
| Sunday |
Snow Level 7000' - 8000' |
| Sunday Night |
Snow Level 7000' - 8000' |
| Monday |
Snow Level 5500' - 6500' |
| Saturday Afternoon |
Snow Level 5500' - 6500' |
* 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 Jan 25, 2018
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