Jump to: Weather Forecast I Snow/Freezing Level I Precipitation I Free Winds 5k I Free Winds 9k I Extended Weather
Weather Synopsis for Wednesday night through Friday
A winter storm is on our doorstep early this afternoon. A Pacific frontal band will spread increasing precipitation over the area later this afternoon and tonight. The front will split and weaken as in moves inland; the parent low is in the Gulf of Alaska, while a consolidated westerly jet is aimed into northern California/southern Oregon. This will translate into heavier precipitation for the volcanoes versus the Cascade Passes tonight.
The front will pass through the Cascades in the wee morning hours. This will flip the Pass level flow from easterly to westerly, allowing an already marginal snow-maker for Snoqualmie Pass to turn to rain at Pass level (3000'). Post frontal showers in westerly flow will pile fresh accumulations along the west slopes of the Olympics and Cascades above 3500-4000 ft Thursday. A trailing shortwave should invigorate shower coverage and intensity Thursday afternoon.
Snow levels will drop below 3000' Thursday evening as showers continue in westerly flow. The westerly flow will be strong Thursday night, look for strong west winds near ridgetops along the east slopes of the Cascades. Weak ridging over the area on Friday will lead to a decrease in showers and alpine winds.
Through Friday morning, this pattern should drop about 1-3 feet of snow along the west slopes of the Cascades, Olympics and Mt. Hood and 6-18 inches along the east slopes of the Cascades.
Weather Forecast
Hurricane Ridge
| Wednesday Night | Light to occasionally moderate rain and snow. Windy. |
| Thursday | Light rain and snow showers. Cooler. |
Mt. Baker
| Wednesday Night | Moderate rain and snow. Windy. |
| Thursday | Light to moderate rain and snow showers, heavier in the afternoon. Cooler. |
Washington Pass and Leavenworth
| Wednesday Night | Light rain and snow, occasionally becoming moderate after midnight. Alpine winds increasing late tonight. |
| Thursday | Light to occasionally moderate rain and snow showers, heaviest near the crest. Cooler. |
Stevens and Snoqualmie Pass
| Wednesday Night | Light to occasionally moderate rain and snow. Light to moderate east winds in the Passes becoming west late tonight. Warming trend late tonight. |
| Thursday | Light to moderate rain and snow showers, heavier in the afternoon. Cooler. Windy along ridgetops. Light to moderate west winds in the Passes. |
Mt. Rainier, Crystal and White Pass
| Wednesday Night | Light to occasionally moderate rain and snow, heaviest Paradise area. Windy. |
| Thursday | Light to moderate rain and snow showers, heavier in the afternoon. Cooler. Windy. |
Mt. Hood
| Wednesday Night | Moderate rain and snow developing this evening. Windy. |
| Thursday | Light to moderate rain and snow showers, heavier in the afternoon. Cooler. Very windy. |
Issued: 1:34 PM PST Wednesday, December 11, 2019
Snow/Freezing Level (ft)
| Hurricane Ridge | Mt. Baker | Washington Pass | Leavenworth | Stevens Pass | Snoqualmie Pass | Mt. Rainier, Crystal & White Pass | Mt. Hood | ||
|---|---|---|---|---|---|---|---|---|---|
| Wednesday Evening | Snow Level * | 5000' | 3500' | 1000' | 1500' | 2000' | 3000' | 5000' | 6000' |
| Wednesday Night | Snow Level * | 4500' | 4000' | 2500' | 2500' | 2500' | 4000' | 5000' | 5000' |
| Thursday Morning | Snow Level | 3500' | 3500' | 3500' | 3500' | 3500' | 3500' | 4000' | 4500' |
| Thursday Afternoon | Snow Level | 3500' | 3500' | 3500' | 3500' | 3500' | 3500' | 4000' | 4500' |
| Thursday Evening | Snow Level | 3500' | 3000' | 3500' | 4000' | 3000' | 3000' | 3000' | 3500' |
| Thursday Night | Snow Level | 3000' | 3000' | 2000' | 3000' | 3000' | 3000' | 3000' | 3500' |
| Friday Morning | Snow Level | 2500' | 2500' | 2000' | 2000' | 2000' | 2500' | 2500' | 3500' |
| Friday Afternoon | Snow Level | 2500' | 2500' | 2000' | 2000' | 2000' | 2500' | 2500' | 3500' |
| Hurricane Ridge | Elevation |
|---|---|
| Wednesday Evening |
Snow Level 5000' (Easterly Flow *) |
| Wednesday Night |
Snow Level 4500' (Easterly Flow *) |
| Thursday Morning |
Snow Level 3500' |
| Thursday Afternoon |
Snow Level 3500' |
| Thursday Evening |
Snow Level 3500' |
| Thursday Night |
Snow Level 3000' |
| Friday Morning |
Snow Level 2500' |
| Friday Afternoon |
Snow Level 2500' |
| Mt. Baker | Elevation |
|---|---|
| Wednesday Evening |
Snow Level 3500' (Easterly Flow *) |
| Wednesday Night |
Snow Level 4000' (Easterly Flow *) |
| Thursday Morning |
Snow Level 3500' |
| Thursday Afternoon |
Snow Level 3500' |
| Thursday Evening |
Snow Level 3000' |
| Thursday Night |
Snow Level 3000' |
| Friday Morning |
Snow Level 2500' |
| Friday Afternoon |
Snow Level 2500' |
| Washington Pass | Elevation |
|---|---|
| Wednesday Evening |
Snow Level 1000' (Easterly Flow *) |
| Wednesday Night |
Snow Level 2500' (Easterly Flow *) |
| Thursday Morning |
Snow Level 3500' |
| Thursday Afternoon |
Snow Level 3500' |
| Thursday Evening |
Snow Level 3500' |
| Thursday Night |
Snow Level 2000' |
| Friday Morning |
Snow Level 2000' |
| Friday Afternoon |
Snow Level 2000' |
| Leavenworth | Elevation |
|---|---|
| Wednesday Evening |
Snow Level 1500' (Easterly Flow *) |
| Wednesday Night |
Snow Level 2500' (Easterly Flow *) |
| Thursday Morning |
Snow Level 3500' |
| Thursday Afternoon |
Snow Level 3500' |
| Thursday Evening |
Snow Level 4000' |
| Thursday Night |
Snow Level 3000' |
| Friday Morning |
Snow Level 2000' |
| Friday Afternoon |
Snow Level 2000' |
| Stevens Pass | Elevation |
|---|---|
| Wednesday Evening |
Snow Level 2000' (Easterly Flow *) |
| Wednesday Night |
Snow Level 2500' (Easterly Flow *) |
| Thursday Morning |
Snow Level 3500' |
| Thursday Afternoon |
Snow Level 3500' |
| Thursday Evening |
Snow Level 3000' |
| Thursday Night |
Snow Level 3000' |
| Friday Morning |
Snow Level 2000' |
| Friday Afternoon |
Snow Level 2000' |
| Snoqualmie Pass | Elevation |
|---|---|
| Wednesday Evening |
Snow Level 3000' (Easterly Flow *) |
| Wednesday Night |
Snow Level 4000' (Easterly Flow *) |
| Thursday Morning |
Snow Level 3500' |
| Thursday Afternoon |
Snow Level 3500' |
| Thursday Evening |
Snow Level 3000' |
| Thursday Night |
Snow Level 3000' |
| Friday Morning |
Snow Level 2500' |
| Friday Afternoon |
Snow Level 2500' |
| Mt. Rainier & Crystal | Elevation |
|---|---|
| Wednesday Evening |
Snow Level 5000' (Easterly Flow *) |
| Wednesday Night |
Snow Level 5000' (Easterly Flow *) |
| Thursday Morning |
Snow Level 4000' |
| Thursday Afternoon |
Snow Level 4000' |
| Thursday Evening |
Snow Level 3000' |
| Thursday Night |
Snow Level 3000' |
| Friday Morning |
Snow Level 2500' |
| Friday Afternoon |
Snow Level 2500' |
| Mt. Hood | Elevation |
|---|---|
| Wednesday Evening |
Snow Level 6000' (Easterly Flow *) |
| Wednesday Night |
Snow Level 5000' (Easterly Flow *) |
| Thursday Morning |
Snow Level 4500' |
| Thursday Afternoon |
Snow Level 4500' |
| Thursday Evening |
Snow Level 3500' |
| Thursday Night |
Snow Level 3500' |
| Friday Morning |
Snow Level 3500' |
| Friday Afternoon |
Snow Level 3500' |
* 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 Night | Friday | Friday Night | Friday | |
|---|---|---|---|---|
| 4 pm - 4 am | 4 am - 4 pm | 4 pm - 4 am | 4 am - 4 pm | |
| Hurricane Ridge | 0.50 | 0.25 - 0.50 | LT 0.25 | LT 0.10 |
| Mt Baker Ski Area | 1.00 - 1.50 | 0.50 - 0.75 | 0.25 - 0.50 | LT 0.25 |
| Washington Pass | 0.50 | 0.25 - 0.50 | LT 0.10 | LT 0.10 |
| Leavenworth | 0.25 | LT 0.25 | LT 0.10 | LT 0.10 |
| Stevens Pass | 0.50 | 0.50 - 0.75 | 0.50 | LT 0.25 |
| Snoqualmie Pass | 0.75 | 0.50 - 0.75 | 0.50 | LT 0.25 |
| Mission Ridge | 0.25 | LT 0.25 | LT 0.10 | LT 0.10 |
| Crystal Mt | 0.75 | 0.75 | 0.25 | LT 0.10 |
| Paradise | 1.00 | 1.00 - 1.50 | 0.75 | LT 0.25 |
| White Pass | 0.50 - 0.75 | 0.50 - 0.75 | 0.50 | LT 0.10 |
| Mt Hood Meadows | 0.75 -1.00 | 0.75 | 0.50 | LT 0.25 |
| Timberline | 1.00 | 0.75 -1.00 | 0.50 - 0.75 | LT 0.25 |
| Hurricane Ridge | Precipitation Forecast |
|---|---|
| Wednesday Night | 0.50 |
| Friday | 0.25 - 0.50 |
| Friday Night | LT 0.25 |
| Friday | LT 0.10 |
| Mt Baker Ski Area | Precipitation Forecast |
|---|---|
| Wednesday Night | 1.00 - 1.50 |
| Friday | 0.50 - 0.75 |
| Friday Night | 0.25 - 0.50 |
| Friday | LT 0.25 |
| Washington Pass | Precipitation Forecast |
|---|---|
| Wednesday Night | 0.50 |
| Friday | 0.25 - 0.50 |
| Friday Night | LT 0.10 |
| Friday | LT 0.10 |
| Leavenworth | Precipitation Forecast |
|---|---|
| Wednesday Night | 0.25 |
| Friday | LT 0.25 |
| Friday Night | LT 0.10 |
| Friday | LT 0.10 |
| Stevens Pass | Precipitation Forecast |
|---|---|
| Wednesday Night | 0.50 |
| Friday | 0.50 - 0.75 |
| Friday Night | 0.50 |
| Friday | LT 0.25 |
| Snoqualmie Pass | Precipitation Forecast |
|---|---|
| Wednesday Night | 0.75 |
| Friday | 0.50 - 0.75 |
| Friday Night | 0.50 |
| Friday | LT 0.25 |
| Mission Ridge | Precipitation Forecast |
|---|---|
| Wednesday Night | 0.25 |
| Friday | LT 0.25 |
| Friday Night | LT 0.10 |
| Friday | LT 0.10 |
| Crystal Mt | Precipitation Forecast |
|---|---|
| Wednesday Night | 0.75 |
| Friday | 0.75 |
| Friday Night | 0.25 |
| Friday | LT 0.10 |
| Paradise | Precipitation Forecast |
|---|---|
| Wednesday Night | 1.00 |
| Friday | 1.00 - 1.50 |
| Friday Night | 0.75 |
| Friday | LT 0.25 |
| White Pass | Precipitation Forecast |
|---|---|
| Wednesday Night | 0.50 - 0.75 |
| Friday | 0.50 - 0.75 |
| Friday Night | 0.50 |
| Friday | LT 0.10 |
| Mt Hood Meadows | Precipitation Forecast |
|---|---|
| Wednesday Night | 0.75 -1.00 |
| Friday | 0.75 |
| Friday Night | 0.50 |
| Friday | LT 0.25 |
| Timberline | Precipitation Forecast |
|---|---|
| Wednesday Night | 1.00 |
| Friday | 0.75 -1.00 |
| Friday Night | 0.50 - 0.75 |
| Friday | 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: 1:34 PM PST Wednesday, December 11, 2019
Free Winds at 5000' (mph)
| Hurricane Ridge | Mt. Baker | Stevens to Snoqualmie Pass | Mt. Rainier | Mt. Hood | |
|---|---|---|---|---|---|
| Wednesday Evening | SW 25 - 35 | SSW 20 - 30 | SE 15 - 25 | S 15 - 25 | SW 20 - 30 |
| Wednesday Night | SW 20 - 30 | SW 20 - 30 | WSW 20 - 30 | SW 20 - 30 | WSW 30 - 40 |
| Thursday Morning | SW 10 - 20 | SSW 10 - 20 | WSW 20 - 30 | SW 10 - 20 | SW 20 - 30 |
| Thursday Afternoon | WSW 15 - 25 | SW 15 - 25 | SW 15 - 25 | SW 20 - 30 | WSW 35 - 45 |
| Hurricane Ridge | Elevation |
|---|---|
| Wednesday Evening | SW 25 - 35 |
| Wednesday Night | SW 20 - 30 |
| Thursday Morning | SW 10 - 20 |
| Thursday Afternoon | WSW 15 - 25 |
| Mt. Baker | Elevation |
|---|---|
| Wednesday Evening | SSW 20 - 30 |
| Wednesday Night | SW 20 - 30 |
| Thursday Morning | SSW 10 - 20 |
| Thursday Afternoon | SW 15 - 25 |
| Stevens and Snoqualmie Pass | Elevation |
|---|---|
| Wednesday Evening | SE 15 - 25 |
| Wednesday Night | WSW 20 - 30 |
| Thursday Morning | WSW 20 - 30 |
| Thursday Afternoon | SW 15 - 25 |
| Mt. Rainier | Elevation |
|---|---|
| Wednesday Evening | S 15 - 25 |
| Wednesday Night | SW 20 - 30 |
| Thursday Morning | SW 10 - 20 |
| Thursday Afternoon | SW 20 - 30 |
| Mt. Hood | Elevation |
|---|---|
| Wednesday Evening | SW 20 - 30 |
| Wednesday Night | WSW 30 - 40 |
| Thursday Morning | SW 20 - 30 |
| Thursday Afternoon | WSW 35 - 45 |
| Hurricane Ridge | Direction - Speed |
|---|---|
| Wednesday Evening | SW 25 - 35 |
| Wednesday Night | SW 20 - 30 |
| Thursday Morning | SW 10 - 20 |
| Thursday Afternoon | WSW 15 - 25 |
| Mt. Baker | Direction - Speed |
|---|---|
| Wednesday Evening | SSW 20 - 30 |
| Wednesday Night | SW 20 - 30 |
| Thursday Morning | SSW 10 - 20 |
| Thursday Afternoon | SW 15 - 25 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Wednesday Evening | SE 15 - 25 |
| Wednesday Night | WSW 20 - 30 |
| Thursday Morning | WSW 20 - 30 |
| Thursday Afternoon | SW 15 - 25 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Wednesday Evening | S 15 - 25 |
| Wednesday Night | SW 20 - 30 |
| Thursday Morning | SW 10 - 20 |
| Thursday Afternoon | SW 20 - 30 |
| Mt. Hood | Direction - Speed |
|---|---|
| Wednesday Evening | SW 20 - 30 |
| Wednesday Night | WSW 30 - 40 |
| Thursday Morning | SW 20 - 30 |
| Thursday Afternoon | WSW 35 - 45 |
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 | |
|---|---|---|---|---|---|
| Wednesday Evening | SW 30 - 40 | SW 25 - 35 | SW 30 - 40 | SW 35 - 45 | SW 35 - 45 |
| Wednesday Night | SW 35 - 45 | WSW 30 - 40 | WSW 45 - 55 | WSW 40 - 50 | WSW 50 - 60 |
| Thursday Morning | WSW 30 - 40 | WSW 40 - 50 | W 40 - 50 | WSW 35 - 45 | W 40 - 50 |
| Thursday Afternoon | SW 20 - 30 | SW 15 - 25 | WSW 40 - 50 | WSW 40 - 50 | WSW 50 - 60 |
| Mt. Baker | Direction - Speed |
|---|---|
| Wednesday Evening | SW 30 - 40 |
| Wednesday Night | SW 35 - 45 |
| Thursday Morning | WSW 30 - 40 |
| Thursday Afternoon | SW 20 - 30 |
| Washington Pass | Direction - Speed |
|---|---|
| Wednesday Evening | SW 25 - 35 |
| Wednesday Night | WSW 30 - 40 |
| Thursday Morning | WSW 40 - 50 |
| Thursday Afternoon | SW 15 - 25 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Wednesday Evening | SW 30 - 40 |
| Wednesday Night | WSW 45 - 55 |
| Thursday Morning | W 40 - 50 |
| Thursday Afternoon | WSW 40 - 50 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Wednesday Evening | SW 35 - 45 |
| Wednesday Night | WSW 40 - 50 |
| Thursday Morning | WSW 35 - 45 |
| Thursday Afternoon | WSW 40 - 50 |
| Mt. Hood | Direction - Speed |
|---|---|
| Wednesday Evening | SW 35 - 45 |
| Wednesday Night | WSW 50 - 60 |
| Thursday Morning | W 40 - 50 |
| Thursday Afternoon | WSW 50 - 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: 1:34 PM PST Wednesday, December 11, 2019
Extended Weather Synopsis for Friday night through Friday
We'll be in a benign and cool weather pattern Saturday as a low-pressure system dives south off the Oregon coast. There should be a fair amount of cloud cover and low freezing levels, but no impactful weather. The majority of forecast models keep the precipitation to our south on Saturday, but there is a chance that the low-pressure system will glance the Mt. Hood area.
On Sunday, the GFS/Canadian models show we are dry with NW flow aloft and a frontal system offshore. The European model suggests warm frontal moisture will push through the area before lifting north on Monday. Stay tuned as weekend forecast shakes out.
Extended Snow/Freezing Levels
| Mt. Baker | Snoqualmie Pass | Mt. Hood | Easterly Flow * | ||
|---|---|---|---|---|---|
| Friday Night | Snow Level | 1000' - 2000' | 1000' - 2000' | 1000' - 2000' | |
| Saturday | Freezing Level | 1500' - 2500' | 1500' - 2500' | 2500' - 3500' | |
| Saturday Night | Freezing Level | 0' - 1000' | 500' - 1500' | 1500' - 2500' | |
| Sunday | Freezing Level | 0' - 1000' | 500' - 1500' | 2000' - 3000' |
| Mt. Baker | Elevation |
|---|---|
| Friday Night |
Snow Level 1000' - 2000' |
| Saturday |
Freezing Level 1500' - 2500' |
| Saturday Night |
Freezing Level 0' - 1000' |
| Sunday |
Freezing Level 0' - 1000' |
| Snoqualmie Pass | Elevation |
|---|---|
| Friday Night |
Snow Level 1000' - 2000' |
| Saturday |
Freezing Level 1500' - 2500' |
| Saturday Night |
Freezing Level 500' - 1500' |
| Sunday |
Freezing Level 500' - 1500' |
| Mt. Hood | Elevation |
|---|---|
| Friday Night |
Snow Level 1000' - 2000' |
| Saturday |
Freezing Level 2500' - 3500' |
| Saturday Night |
Freezing Level 1500' - 2500' |
| Sunday |
Freezing Level 2000' - 3000' |
* 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 10, 2019
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