Jump to: Weather Forecast I Snow/Freezing Level I Precipitation I Free Winds 5k I Free Winds 9k I Extended Weather
Weather Synopsis for Monday & Thursday
A cold frontal rainband which is tapping into subtropical moisture is sagging slowly southeast across Washington State. The approaching front is bringing moderate to heavy rain and high elevation snow along with increasing moderate to strong crest-level SSW winds. The strongest winds will likely be along the west slopes of the Cascades in the south and central parts, particularly from 2-4 PM. Snow levels are lowering slightly as the front approaches with rain mixing with snow early Monday afternoon at Mt. Baker base and Paradise.
Later this afternoon, the cold front will begin to move more quickly on its SE trajectory, limiting the duration of the heavy precipitation over the central and south Cascades and Hood regions relative to the Olympics and north Cascades.
Washington Pass should see all snow at pass level, while Stevens and Snoqualmie passes will see all rain as the front approaches.
The front will pass the Olympics and NW Cascades around 2-3 PM and the rest of the Cascade crest around 4 PM. The frontal passage will be associated with rapid cooling and a switch to W-SW winds. The Olympics will cool first with a 4000 foot changeover to snow by around 4 PM, followed by the west slopes of the Cascades by around 7PM, and lastly the east slopes of the Cascades and Mt. Hood between 7 and 10 PM.
On Monday night through Tuesday night a shallow trough over our region will bring light to moderate mountain-enhanced snow showers on a moderately moist W-SW flow. Some convergence will be associated with moderate to heavy snow generally north of Stevens Pass at various times.
Weather Forecast
Olympics
| Monday | Moderate rain and high elevation snow. Moderate to strong ridgetop winds. Snow line lowing sharply at the end of the day. |
| Monday Night | Light to moderate snow showers. |
| Tuesday | Light to moderate snow showers. |
| Tuesday Night | Decreasing light to moderate snow showers. |
Washington Cascades near and west of the Crest including Stevens, Snoqualmie and White Passes
| Monday | Moderate to heavy rain and high elevation snow in the north spreading southward during the afternoon and becoming heavy in most locations by the end of the day. Moderate to strong S-SW winds. |
| Monday Night | Heavy rain and snow decreasing and becoming light to moderate snow showers by 10 PM. Heavier snow in convergence possible north of Stevens Pass. |
| Tuesday | Light to occasional moderate snow showers. Heavier snow in convergence possible north of Stevens Pass. |
| Tuesday Night | Light to occasional moderate snow showers. Heavier snow in convergence possible north of Stevens Pass. |
East Slopes of the Washington Cascades
| Monday | Moderate to heavy rain and mid-to-high elevation snow in the north spreading southward during the afternoon and becoming heavy in most locations by the end of the day. Moderate S and S-SE crest-level winds, possibly becoming strong by afternoon in the south. |
| Monday Night | Heavy rain and snow decreasing and becoming light snow showers by 10 PM. Heavier snow in convergence possible north of Stevens Pass. |
| Tuesday | Light snow showers. Heavier snow in convergence possible north of Stevens Pass. |
| Tuesday Night | Light snow showers. Heavier snow in convergence possible north of Stevens Pass. |
Mt. Hood
| Monday | Clouds thickening and lowering in the afternoon. Rain and snow arriving around 4 PM. Moderate SW winds becoming strong to very strong late in the day in the alpine. |
| Monday Night | Heavy rain and high elevation snow along with strong to very strong SW winds during the evening . Alpine winds becoming moderate to strong as precipitation decreases to light snow showers after midnight. |
| Tuesday | Light snow showers. |
| Tuesday Night | Light snow showers. |
Issued: 2:38 PM PST Monday, January 29, 2018
Snow/Freezing Level (ft)
| Hurricane Ridge | Mt. Baker | Washington Pass | Leavenworth | Stevens Pass | Snoqualmie Pass | Mt. Rainier, Crystal & White Pass | Mt. Hood | ||
|---|---|---|---|---|---|---|---|---|---|
| Monday Afternoon | Snow Level * | 3500' | 4500' | 4500' | ' | ' | 6000' | ' | 7000' |
| Monday Night | Snow Level | 2000' | 2000' | 2000' | ' | ' | 2000' | ' | 3500' |
| Tuesday Morning | Snow Level | 2000' | 2000' | 2000' | ' | ' | 2000' | ' | 2500' |
| Tuesday Afternoon | Snow Level | 1500' | 1500' | 1500' | ' | ' | 1500' | ' | 2500' |
| Tuesday Night | Snow Level | 1000' | 1000' | 0' | ' | ' | 1000' | ' | 2000' |
| Hurricane Ridge | Elevation |
|---|---|
| Monday Afternoon |
Snow Level 3500' (Easterly Flow *) |
| Monday Night |
Snow Level 2000' |
| Tuesday Morning |
Snow Level 2000' |
| Tuesday Afternoon |
Snow Level 1500' |
| Tuesday Night |
Snow Level 1000' |
| Mt. Baker | Elevation |
|---|---|
| Monday Afternoon |
Snow Level 4500' (Easterly Flow *) |
| Monday Night |
Snow Level 2000' |
| Tuesday Morning |
Snow Level 2000' |
| Tuesday Afternoon |
Snow Level 1500' |
| Tuesday Night |
Snow Level 1000' |
| Washington Pass | Elevation |
|---|---|
| Monday Afternoon |
Snow Level 4500' (Easterly Flow *) |
| Monday Night |
Snow Level 2000' |
| Tuesday Morning |
Snow Level 2000' |
| Tuesday Afternoon |
Snow Level 1500' |
| Tuesday Night |
Snow Level 0' |
| Leavenworth | Elevation |
|---|---|
| Monday Afternoon |
Snow Level ' (Easterly Flow *) |
| Monday Night |
Snow Level ' |
| Tuesday Morning |
Snow Level ' |
| Tuesday Afternoon |
Snow Level ' |
| Tuesday Night |
Snow Level ' |
| Stevens Pass | Elevation |
|---|---|
| Monday Afternoon |
Snow Level ' (Easterly Flow *) |
| Monday Night |
Snow Level ' |
| Tuesday Morning |
Snow Level ' |
| Tuesday Afternoon |
Snow Level ' |
| Tuesday Night |
Snow Level ' |
| Snoqualmie Pass | Elevation |
|---|---|
| Monday Afternoon |
Snow Level 6000' (Easterly Flow *) |
| Monday Night |
Snow Level 2000' |
| Tuesday Morning |
Snow Level 2000' |
| Tuesday Afternoon |
Snow Level 1500' |
| Tuesday Night |
Snow Level 1000' |
| Mt. Rainier & Crystal | Elevation |
|---|---|
| Monday Afternoon |
Snow Level ' (Easterly Flow *) |
| Monday Night |
Snow Level ' |
| Tuesday Morning |
Snow Level ' |
| Tuesday Afternoon |
Snow Level ' |
| Tuesday Night |
Snow Level ' |
| Mt. Hood | Elevation |
|---|---|
| Monday Afternoon |
Snow Level 7000' (Easterly Flow *) |
| Monday Night |
Snow Level 3500' |
| Tuesday Morning |
Snow Level 2500' |
| Tuesday Afternoon |
Snow Level 2500' |
| Tuesday Night |
Snow Level 2000' |
* 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 | 0 - 0.50 |
| Mt Baker Ski Area | 2.50 - 3.00 | 0 - 0.75 |
| Washington Pass | 1.00 - 1.50 | 0.25 - 0.50 |
| Stevens Pass | 0.75 - 1.00 | 0 - 0.75 |
| Snoqualmie Pass | 0 - 1.00 | 0.75 - 1.00 |
| Mission Ridge | LT 0.25 | LT 0.25 |
| Crystal Mt | 0.75 - 1.00 | 0.25 - 0.50 |
| Paradise | 1.00 - 1.50 | 0 - 1.00 |
| White Pass | 0 - 1.00 | 0.75 - 1.00 |
| Mt Hood Meadows | 0 - 0.75 | 0.25 - 0.50 |
| Timberline | 0.75 - 1.00 | 0 - 0.50 |
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 Monday, January 29, 2018
Free Winds at 5000' (mph)
| Hurricane Ridge | Mt. Baker | Stevens to Snoqualmie Pass | Mt. Rainier | Mt. Hood | |
|---|---|---|---|---|---|
| Monday Afternoon | SW 15 - 25 | SW 20 - 30 | SW 30 - 40 | --- - | SW 40 - 60 |
| Monday Night | WSW 20 - 30 | WSW 20 - 30 | WSW 20 - 30 | --- - | WSW 30 - 40 |
| Tuesday Morning | WSW 20 - 30 | SW 20 - 30 | WSW 20 - 30 | --- - | WSW 30 - 40 |
| Tuesday Afternoon | WSW 20 - 30 | WSW 15 - 25 | WSW 20 - 30 | --- - | WSW 25 - 35 |
| Tuesday Night | W 10 - 20 | W 10 - 20 | W 15 - 25 | --- - | W 20 - 30 |
| Hurricane Ridge | Elevation |
|---|---|
| Monday Afternoon | SW 15 - 25 |
| Monday Night | WSW 20 - 30 |
| Tuesday Morning | WSW 20 - 30 |
| Tuesday Afternoon | WSW 20 - 30 |
| Tuesday Night | W 10 - 20 |
| Mt. Baker | Elevation |
|---|---|
| Monday Afternoon | SW 20 - 30 |
| Monday Night | WSW 20 - 30 |
| Tuesday Morning | SW 20 - 30 |
| Tuesday Afternoon | WSW 15 - 25 |
| Tuesday Night | W 10 - 20 |
| Stevens and Snoqualmie Pass | Elevation |
|---|---|
| Monday Afternoon | SW 30 - 40 |
| Monday Night | WSW 20 - 30 |
| Tuesday Morning | WSW 20 - 30 |
| Tuesday Afternoon | WSW 20 - 30 |
| Tuesday Night | W 15 - 25 |
| Mt. Rainier | Elevation |
|---|---|
| Monday Afternoon | --- - |
| Monday Night | --- - |
| Tuesday Morning | --- - |
| Tuesday Afternoon | --- - |
| Tuesday Night | --- - |
| Mt. Hood | Elevation |
|---|---|
| Monday Afternoon | SW 40 - 60 |
| Monday Night | WSW 30 - 40 |
| Tuesday Morning | WSW 30 - 40 |
| Tuesday Afternoon | WSW 25 - 35 |
| Tuesday Night | W 20 - 30 |
| Hurricane Ridge | Direction - Speed |
|---|---|
| Monday Afternoon | SW 15 - 25 |
| Monday Night | WSW 20 - 30 |
| Tuesday Morning | WSW 20 - 30 |
| Tuesday Afternoon | WSW 20 - 30 |
| Tuesday Night | W 10 - 20 |
| Mt. Baker | Direction - Speed |
|---|---|
| Monday Afternoon | SW 20 - 30 |
| Monday Night | WSW 20 - 30 |
| Tuesday Morning | SW 20 - 30 |
| Tuesday Afternoon | WSW 15 - 25 |
| Tuesday Night | W 10 - 20 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Monday Afternoon | SW 30 - 40 |
| Monday Night | WSW 20 - 30 |
| Tuesday Morning | WSW 20 - 30 |
| Tuesday Afternoon | WSW 20 - 30 |
| Tuesday Night | W 15 - 25 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Monday Afternoon | --- - |
| Monday Night | --- - |
| Tuesday Morning | --- - |
| Tuesday Afternoon | --- - |
| Tuesday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| Monday Afternoon | SW 40 - 60 |
| Monday Night | WSW 30 - 40 |
| Tuesday Morning | WSW 30 - 40 |
| Tuesday Afternoon | WSW 25 - 35 |
| Tuesday Night | W 20 - 30 |
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 | |
|---|---|---|---|---|---|
| Monday Morning | SW 50 - 70 | SW 50 - 70 | SW 60 - 80 | --- - | SW 50 - 70 |
| Monday Afternoon | SW 55 - 75 | SW 55 - 75 | SW 60 - 80 | --- - | SW 65 - 85 |
| Monday Night | WSW 40 - 60 | WSW 45 - 65 | WSW 45 - 65 | --- - | WSW 70 - 90 |
| Tuesday Morning | SW 30 - 40 | SW 35 - 50 | SW 40 - 60 | --- - | WSW 35 - 50 |
| Tuesday Afternoon | SW 30 - 40 | SW 35 - 50 | SW 40 - 60 | --- - | SW 35 - 50 |
| Tuesday Night | WSW 25 - 35 | WSW 30 - 40 | W 30 - 40 | --- - | W 40 - 60 |
| Mt. Baker | Direction - Speed |
|---|---|
| Monday Morning | SW 50 - 70 |
| Monday Afternoon | SW 55 - 75 |
| Monday Night | WSW 40 - 60 |
| Tuesday Morning | SW 30 - 40 |
| Tuesday Afternoon | SW 30 - 40 |
| Tuesday Night | WSW 25 - 35 |
| Washington Pass | Direction - Speed |
|---|---|
| Monday Morning | SW 50 - 70 |
| Monday Afternoon | SW 55 - 75 |
| Monday Night | WSW 45 - 65 |
| Tuesday Morning | SW 35 - 50 |
| Tuesday Afternoon | SW 35 - 50 |
| Tuesday Night | WSW 30 - 40 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Monday Morning | SW 60 - 80 |
| Monday Afternoon | SW 60 - 80 |
| Monday Night | WSW 45 - 65 |
| Tuesday Morning | SW 40 - 60 |
| Tuesday Afternoon | SW 40 - 60 |
| Tuesday Night | W 30 - 40 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Monday Morning | --- - |
| Monday Afternoon | --- - |
| Monday Night | --- - |
| Tuesday Morning | --- - |
| Tuesday Afternoon | --- - |
| Tuesday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| Monday Morning | SW 50 - 70 |
| Monday Afternoon | SW 65 - 85 |
| Monday Night | WSW 70 - 90 |
| Tuesday Morning | WSW 35 - 50 |
| Tuesday Afternoon | SW 35 - 50 |
| Tuesday Night | W 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.
Issued: 2:38 PM PST Monday, January 29, 2018
Extended Weather Synopsis for Thursday night through Thursday
On Wednesday, a strong jet will lift north, allowing a broad high pressure ridge aloft to begin working into from the coastal waters. Some moisture will continue to ride over the ridge. through Wednesday night.
A series of weak shortwave systems move pver the shallow, broad ridge and across the region Thursday through Friday with uncertain timing and strength as they impact our region. However, models generally agree that significant warming will occur Thursday or Thursday night and will remain for the duration of the remainder of the forecast outlook. The series of compact systems will bring moderate to occasionally strong westerly winds , which should be strongest in the Cascade passes.
Extended Weather
Olympics, Washington Cascades and Mt. Hood Area
Extended Snow/Freezing Levels
| Mt. Baker | Snoqualmie Pass | Mt. Hood | Easterly Flow * | ||
|---|---|---|---|---|---|
| Wednesday | Snow Level | 1000' - 2000' | 1000' - 2000' | 2000' - 3000' | |
| Wednesday Night | Snow Level | 1000' - 2000' | 1500' - 2500' | 2500' - 3500' | |
| Thursday | Snow Level | 2000' - 3000' | 2500' - 3500' | 4500' - 6500' | |
| Thursday Night | Snow Level | 3500' - 5500' | 5000' - 7000' | 7500' - 8500' | |
| Friday | Snow Level | 3500' - 4500' | 4500' - 5500' | 7000' - 8000' |
| Mt. Baker | Elevation |
|---|---|
| Wednesday |
Snow Level 1000' - 2000' |
| Wednesday Night |
Snow Level 1000' - 2000' |
| Thursday |
Snow Level 2000' - 3000' |
| Thursday Night |
Snow Level 3500' - 5500' |
| Friday |
Snow Level 3500' - 4500' |
| Snoqualmie Pass | Elevation |
|---|---|
| Wednesday |
Snow Level 1000' - 2000' |
| Wednesday Night |
Snow Level 1500' - 2500' |
| Thursday |
Snow Level 2500' - 3500' |
| Thursday Night |
Snow Level 5000' - 7000' |
| Friday |
Snow Level 4500' - 5500' |
| Mt. Hood | Elevation |
|---|---|
| Wednesday |
Snow Level 2000' - 3000' |
| Wednesday Night |
Snow Level 2500' - 3500' |
| Thursday |
Snow Level 4500' - 6500' |
| Thursday Night |
Snow Level 7500' - 8500' |
| Friday |
Snow Level 7000' - 8000' |
* 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 29, 2018
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