Jump to: Weather Forecast I Snow/Freezing Level I Precipitation I Free Winds 5k I Free Winds 9k I Extended Weather
Weather Synopsis for Tuesday night through Friday
Updated 2:30 PM: Synopsis corrected for errant date of convergence activity
We're entering the final stages of a massive storm cycle. A digging trough offshore is pushing into the Pacific Northwest coastal waters. Multiple disturbances have developed on Tuesday and are riding north along a frontal boundary ahead of the trough. These features should move onshore during the late afternoon and evening hours, pushing rain and snow back throughout the entire region after many areas dried somewhat from the late morning through the afternoon. The surface front should cross the Cascades during the evening hours with SSW winds switching SW and then gradually westerly after midnight in association with a secondary frontal feature that may bring another shot of precipitation and stronger cooling. At this time it appears that winds will be strongest in the south Cascades and Mt. Hood areas where alpine areas may see more extreme winds. Rain and snow should start at higher elevations (4000-5000 ft) and gradually drop throughout the night, with stronger cooling associated with a secondary cold front moving through overnight. Snow levels should reach Snoqualmie Pass levels by Wednesday morning.
A trough sits over the region Wednesday. Models indicate post-frontal convergence in the Stevens Pass and potentially Mt. Baker vicinities during the overnight hours. We don't normally talk about a Vancouver Island Convergence zone, but they do exist. The Puget Sound convergence likely shifts southward toward Snoqualmie Pass by Wednesday morning, but should weaken as general shower activity becomes light on Wednesday. Temperatures should be much colder on Wednesday with snow (not rain) in most mountain locations.
Snow shower activity further tapers Wednesday night as an offshore low drop south toward southern Oregon, reducing the WNW flow.
WNW flow should increase once again on Thursday with a ridge offshore and the trough sliding eastward and some weak shower or convergence activity is possible. Cold temperatures remain in place with snow levels approaching sea level northern Washington State.
Weather Forecast
Hurricane Ridge
| Tuesday Night | Decreasing light rain and snow becoming showery from late evening onward. Strong cooling. |
| Wednesday | Mostly cloudy with a chance of snow showers. Colder. |
Mt. Baker
| Tuesday Night | Heavy rain and snow with strong alpine winds in the evening, decreasing slightly overnight. Gradual cooling trend. |
| Wednesday | Vancouver Island convergence zone may develop near or just south of the Mt. Baker area in the morning. Otherwise, expect decreasing light snow showers and much colder temperatures. |
Washington Pass and Leavenworth
| Tuesday Night | Light to moderate rain and snow decreasing after midnight. Cooling temperatures. Strong alpine winds in the evening, decreasing. |
| Wednesday | Rapid cooling with very light snow showers near the Cascade Crest tapering through the day. |
Stevens and Snoqualmie Pass
| Tuesday Night | Moderate to heavy rain and snow. Convergence developing after midnight, most likely in Stevens Viscinity. Strong alpine winds decreasing after midnight. Cooling temperatures. Light W wind becoming moderate by late evening. |
| Wednesday | Light to moderate snow showers, heaviest in convergence likely shifting southward slightly and may affect Stevens or Snoqualmie. Further cooling early in the day. Moderate W winds through he Passes. |
Mt. Rainier, Crystal and White Pass
| Tuesday Night | Heavy rain and snow at Paradise, moderate at White Pass and light to moderate at Crystal, decreasing in all locations after midnight. Cooling temperatures. Strong to extreme alpine winds, decreasing after midnight. |
| Wednesday | Decreasing light snow showers. Colder temperatures. |
Mt. Hood
| Tuesday Night | Increasing precipitation becoming heavy from mid-evening onwards. Cooling temperatures throughout the night. Strong to extreme winds in the evening, decreasing through the night. Cooling temperatures. |
| Wednesday | Decreasing moderate snow showers becoming light in the afternoon. Further cooling temperatures. Strong to extreme alpine winds. |
Issued: 2:32 PM PST Tuesday, January 7, 2020
Snow/Freezing Level (ft)
| Hurricane Ridge | Mt. Baker | Washington Pass | Leavenworth | Stevens Pass | Snoqualmie Pass | Mt. Rainier, Crystal & White Pass | Mt. Hood | ||
|---|---|---|---|---|---|---|---|---|---|
| Tuesday Evening | Snow Level | 4000' | 4000' | 4000' | 4000' | 4000' | 4000' | 4000' | 4000' |
| Tuesday Night | Snow Level | 2500' | 3000' | 3500' | 3500' | 3500' | 3000' | 3000' | 3500' |
| Wednesday Morning | Snow Level | 1000' | 1000' | 1500' | 2000' | 2000' | 1500' | 1500' | 2500' |
| Wednesday Afternoon | Snow Level | 1500' | 1000' | 1000' | 2000' | 1500' | 1000' | 1500' | 2000' |
| Wednesday Evening | Snow Level | 1000' | 500' | 500' | 1000' | 1000' | 1000' | 1000' | 1500' |
| Wednesday Night | Snow Level | 500' | 0' | 0' | 0' | 0' | 500' | 0' | 1500' |
| Thursday Morning | Snow Level | 500' | 0' | 0' | 0' | 0' | 500' | 0' | 1000' |
| Thursday Afternoon | Snow Level | 1500' | 0' | 500' | 1500' | 1000' | 1000' | 1000' | 1500' |
| Hurricane Ridge | Elevation |
|---|---|
| Tuesday Evening |
Snow Level 4000' |
| Tuesday Night |
Snow Level 2500' |
| Wednesday Morning |
Snow Level 1000' |
| Wednesday Afternoon |
Snow Level 1500' |
| Wednesday Evening |
Snow Level 1000' |
| Wednesday Night |
Snow Level 500' |
| Thursday Morning |
Snow Level 500' |
| Thursday Afternoon |
Snow Level 1500' |
| Mt. Baker | Elevation |
|---|---|
| Tuesday Evening |
Snow Level 4000' |
| Tuesday Night |
Snow Level 3000' |
| Wednesday Morning |
Snow Level 1000' |
| Wednesday Afternoon |
Snow Level 1000' |
| Wednesday Evening |
Snow Level 500' |
| Wednesday Night |
Snow Level 0' |
| Thursday Morning |
Snow Level 0' |
| Thursday Afternoon |
Snow Level 0' |
| Washington Pass | Elevation |
|---|---|
| Tuesday Evening |
Snow Level 4000' |
| Tuesday Night |
Snow Level 3500' |
| Wednesday Morning |
Snow Level 1500' |
| Wednesday Afternoon |
Snow Level 1000' |
| Wednesday Evening |
Snow Level 500' |
| Wednesday Night |
Snow Level 0' |
| Thursday Morning |
Snow Level 0' |
| Thursday Afternoon |
Snow Level 500' |
| Leavenworth | Elevation |
|---|---|
| Tuesday Evening |
Snow Level 4000' |
| Tuesday Night |
Snow Level 3500' |
| Wednesday Morning |
Snow Level 2000' |
| Wednesday Afternoon |
Snow Level 2000' |
| Wednesday Evening |
Snow Level 1000' |
| Wednesday Night |
Snow Level 0' |
| Thursday Morning |
Snow Level 0' |
| Thursday Afternoon |
Snow Level 1500' |
| Stevens Pass | Elevation |
|---|---|
| Tuesday Evening |
Snow Level 4000' |
| Tuesday Night |
Snow Level 3500' |
| Wednesday Morning |
Snow Level 2000' |
| Wednesday Afternoon |
Snow Level 1500' |
| Wednesday Evening |
Snow Level 1000' |
| Wednesday Night |
Snow Level 0' |
| Thursday Morning |
Snow Level 0' |
| Thursday Afternoon |
Snow Level 1000' |
| Snoqualmie Pass | Elevation |
|---|---|
| Tuesday Evening |
Snow Level 4000' |
| Tuesday Night |
Snow Level 3000' |
| Wednesday Morning |
Snow Level 1500' |
| Wednesday Afternoon |
Snow Level 1000' |
| Wednesday Evening |
Snow Level 1000' |
| Wednesday Night |
Snow Level 500' |
| Thursday Morning |
Snow Level 500' |
| Thursday Afternoon |
Snow Level 1000' |
| Mt. Rainier & Crystal | Elevation |
|---|---|
| Tuesday Evening |
Snow Level 4000' |
| Tuesday Night |
Snow Level 3000' |
| Wednesday Morning |
Snow Level 1500' |
| Wednesday Afternoon |
Snow Level 1500' |
| Wednesday Evening |
Snow Level 1000' |
| Wednesday Night |
Snow Level 0' |
| Thursday Morning |
Snow Level 0' |
| Thursday Afternoon |
Snow Level 1000' |
| Mt. Hood | Elevation |
|---|---|
| Tuesday Evening |
Snow Level 4000' |
| Tuesday Night |
Snow Level 3500' |
| Wednesday Morning |
Snow Level 2500' |
| Wednesday Afternoon |
Snow Level 2000' |
| Wednesday Evening |
Snow Level 1500' |
| Wednesday Night |
Snow Level 1500' |
| Thursday Morning |
Snow Level 1000' |
| Thursday Afternoon |
Snow Level 1500' |
* 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
| Tuesday Night | Friday | Friday Night | Friday | |
|---|---|---|---|---|
| 4 pm - 4 am | 4 am - 4 pm | 4 pm - 4 am | 4 am - 4 pm | |
| Hurricane Ridge | LT 0.25 | LT 0.10 | LT 0.10 | LT 0.10 |
| Mt Baker Ski Area | 1.00 | LT 0.10 | LT 0.10 | LT 0.10 |
| Washington Pass | 0.25 - 0.50 | 0 | LT 0.10 | LT 0.10 |
| Leavenworth | LT 0.10 | 0 | 0 | 0 |
| Stevens Pass | 0.50 - 0.75 | LT 0.25 | LT 0.25 | LT 0.25 |
| Snoqualmie Pass | 0.75 | 0.25 - 0.50 | 0.25 | LT 0.25 |
| Mission Ridge | LT 0.25 | LT 0.10 | 0 | 0 |
| Crystal Mt | 0.25 - 0.50 | LT 0.10 | LT 0.10 | LT 0.10 |
| Paradise | 1.00 | LT 0.25 | LT 0.25 | LT 0.10 |
| White Pass | 0.50 | 0.25 | LT 0.25 | LT 0.10 |
| Mt Hood Meadows | 1.00 | 0.50 | 0.25 | LT 0.25 |
| Timberline | 1.00 | 0.50 - 0.75 | 0.25 | 0.25 |
| Hurricane Ridge | Precipitation Forecast |
|---|---|
| Tuesday Night | LT 0.25 |
| Friday | LT 0.10 |
| Friday Night | LT 0.10 |
| Friday | LT 0.10 |
| Mt Baker Ski Area | Precipitation Forecast |
|---|---|
| Tuesday Night | 1.00 |
| Friday | LT 0.10 |
| Friday Night | LT 0.10 |
| Friday | LT 0.10 |
| Washington Pass | Precipitation Forecast |
|---|---|
| Tuesday Night | 0.25 - 0.50 |
| Friday | 0 |
| Friday Night | LT 0.10 |
| Friday | LT 0.10 |
| Leavenworth | Precipitation Forecast |
|---|---|
| Tuesday Night | LT 0.10 |
| Friday | 0 |
| Friday Night | 0 |
| Friday | 0 |
| Stevens Pass | Precipitation Forecast |
|---|---|
| Tuesday Night | 0.50 - 0.75 |
| Friday | LT 0.25 |
| Friday Night | LT 0.25 |
| Friday | LT 0.25 |
| Snoqualmie Pass | Precipitation Forecast |
|---|---|
| Tuesday Night | 0.75 |
| Friday | 0.25 - 0.50 |
| Friday Night | 0.25 |
| Friday | LT 0.25 |
| Mission Ridge | Precipitation Forecast |
|---|---|
| Tuesday Night | LT 0.25 |
| Friday | LT 0.10 |
| Friday Night | 0 |
| Friday | 0 |
| Crystal Mt | Precipitation Forecast |
|---|---|
| Tuesday Night | 0.25 - 0.50 |
| Friday | LT 0.10 |
| Friday Night | LT 0.10 |
| Friday | LT 0.10 |
| Paradise | Precipitation Forecast |
|---|---|
| Tuesday Night | 1.00 |
| Friday | LT 0.25 |
| Friday Night | LT 0.25 |
| Friday | LT 0.10 |
| White Pass | Precipitation Forecast |
|---|---|
| Tuesday Night | 0.50 |
| Friday | 0.25 |
| Friday Night | LT 0.25 |
| Friday | LT 0.10 |
| Mt Hood Meadows | Precipitation Forecast |
|---|---|
| Tuesday Night | 1.00 |
| Friday | 0.50 |
| Friday Night | 0.25 |
| Friday | LT 0.25 |
| Timberline | Precipitation Forecast |
|---|---|
| Tuesday Night | 1.00 |
| Friday | 0.50 - 0.75 |
| Friday Night | 0.25 |
| Friday | 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: 2:32 PM PST Tuesday, January 7, 2020
Free Winds at 5000' (mph)
| Hurricane Ridge | Mt. Baker | Stevens to Snoqualmie Pass | Mt. Rainier | Mt. Hood | |
|---|---|---|---|---|---|
| Tuesday Evening | WSW 10 - 20 | WSW 15 - 25 | WSW 20 - 30 | WSW 10 - 20 | WSW 20 - 30 |
| Tuesday Night | WSW 15 - 25 | WSW 15 - 25 | WSW 20 - 30 | WSW 15 - 25 | W 30 - 40 |
| Wednesday Morning | WSW 20 - 30 | WSW 15 - 25 | WSW 20 - 30 | W 20 - 30 | W 30 - 40 |
| Wednesday Afternoon | WSW 15 - 25 | W 15 - 25 | W 15 - 25 | W 15 - 25 | W 25 - 35 |
| Hurricane Ridge | Elevation |
|---|---|
| Tuesday Evening | WSW 10 - 20 |
| Tuesday Night | WSW 15 - 25 |
| Wednesday Morning | WSW 20 - 30 |
| Wednesday Afternoon | WSW 15 - 25 |
| Mt. Baker | Elevation |
|---|---|
| Tuesday Evening | WSW 15 - 25 |
| Tuesday Night | WSW 15 - 25 |
| Wednesday Morning | WSW 15 - 25 |
| Wednesday Afternoon | W 15 - 25 |
| Stevens and Snoqualmie Pass | Elevation |
|---|---|
| Tuesday Evening | WSW 20 - 30 |
| Tuesday Night | WSW 20 - 30 |
| Wednesday Morning | WSW 20 - 30 |
| Wednesday Afternoon | W 15 - 25 |
| Mt. Rainier | Elevation |
|---|---|
| Tuesday Evening | WSW 10 - 20 |
| Tuesday Night | WSW 15 - 25 |
| Wednesday Morning | W 20 - 30 |
| Wednesday Afternoon | W 15 - 25 |
| Mt. Hood | Elevation |
|---|---|
| Tuesday Evening | WSW 20 - 30 |
| Tuesday Night | W 30 - 40 |
| Wednesday Morning | W 30 - 40 |
| Wednesday Afternoon | W 25 - 35 |
| Hurricane Ridge | Direction - Speed |
|---|---|
| Tuesday Evening | WSW 10 - 20 |
| Tuesday Night | WSW 15 - 25 |
| Wednesday Morning | WSW 20 - 30 |
| Wednesday Afternoon | WSW 15 - 25 |
| Mt. Baker | Direction - Speed |
|---|---|
| Tuesday Evening | WSW 15 - 25 |
| Tuesday Night | WSW 15 - 25 |
| Wednesday Morning | WSW 15 - 25 |
| Wednesday Afternoon | W 15 - 25 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Tuesday Evening | WSW 20 - 30 |
| Tuesday Night | WSW 20 - 30 |
| Wednesday Morning | WSW 20 - 30 |
| Wednesday Afternoon | W 15 - 25 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Tuesday Evening | WSW 10 - 20 |
| Tuesday Night | WSW 15 - 25 |
| Wednesday Morning | W 20 - 30 |
| Wednesday Afternoon | W 15 - 25 |
| Mt. Hood | Direction - Speed |
|---|---|
| Tuesday Evening | WSW 20 - 30 |
| Tuesday Night | W 30 - 40 |
| Wednesday Morning | W 30 - 40 |
| Wednesday Afternoon | W 25 - 35 |
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 | |
|---|---|---|---|---|---|
| Tuesday Evening | WSW 25 - 35 | WSW 25 - 35 | WSW 35 - 45 | W 30 - 40 | W 35 - 45 |
| Tuesday Night | WSW 35 - 45 | W 35 - 45 | W 35 - 45 | W 35 - 45 | W 40 - 55 |
| Wednesday Morning | WSW 20 - 30 | W 30 - 40 | W 35 - 45 | W 35 - 45 | W 45 - 60 |
| Wednesday Afternoon | W 15 - 25 | W 20 - 30 | WSW 30 - 40 | W 35 - 45 | W 40 - 50 |
| Mt. Baker | Direction - Speed |
|---|---|
| Tuesday Evening | WSW 25 - 35 |
| Tuesday Night | WSW 35 - 45 |
| Wednesday Morning | WSW 20 - 30 |
| Wednesday Afternoon | W 15 - 25 |
| Washington Pass | Direction - Speed |
|---|---|
| Tuesday Evening | WSW 25 - 35 |
| Tuesday Night | W 35 - 45 |
| Wednesday Morning | W 30 - 40 |
| Wednesday Afternoon | W 20 - 30 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Tuesday Evening | WSW 35 - 45 |
| Tuesday Night | W 35 - 45 |
| Wednesday Morning | W 35 - 45 |
| Wednesday Afternoon | WSW 30 - 40 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Tuesday Evening | W 30 - 40 |
| Tuesday Night | W 35 - 45 |
| Wednesday Morning | W 35 - 45 |
| Wednesday Afternoon | W 35 - 45 |
| Mt. Hood | Direction - Speed |
|---|---|
| Tuesday Evening | W 35 - 45 |
| Tuesday Night | W 40 - 55 |
| Wednesday Morning | W 45 - 60 |
| Wednesday Afternoon | W 40 - 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: 2:32 PM PST Tuesday, January 7, 2020
Extended Weather Synopsis for Friday night through Friday
Thursday night, a low approaches on NW flow with SSW winds increasing ahead of it overnight as light snow begins after midnight. On Friday, the snow intensifies throughout the day, with snow levels beginning to rise up to 1500-2500 ft by the end of the day as the surface cold front reaches the coastline. Friday night, the cold front passes with heavy snow in the evening and moderate snow shower activity behind it. Snow levels should peak below Cascade Pass level with E flow switching westerly. A secondary low should enhance snowfall which may be heavy with a cold trough in place.
Extended Snow/Freezing Levels
| Mt. Baker | Snoqualmie Pass | Mt. Hood | Easterly Flow * | ||
|---|---|---|---|---|---|
| Thursday Night | Snow Level | 0' - 0' | 0' - 1000' | 500' - 1500' | |
| Friday | Snow Level | 0' - 1000' | 500' - 1500' | 500' - 2500' | * |
| Friday Night | Snow Level | 1000' - 2000' | 1500' - 2500' | 2000' - 3000' | |
| Saturday | Snow Level | 1500' - 2500' | 1500' - 2500' | 2000' - 3000' |
| Mt. Baker | Elevation |
|---|---|
| Thursday Night |
Snow Level 0' - 0' |
| Friday |
Snow Level 0' - 1000' (Easterly Flow *) |
| Friday Night |
Snow Level 1000' - 2000' |
| Saturday |
Snow Level 1500' - 2500' |
| Snoqualmie Pass | Elevation |
|---|---|
| Thursday Night |
Snow Level 0' - 1000' |
| Friday |
Snow Level 500' - 1500' (Easterly Flow *) |
| Friday Night |
Snow Level 1500' - 2500' |
| Saturday |
Snow Level 1500' - 2500' |
| Mt. Hood | Elevation |
|---|---|
| Thursday Night |
Snow Level 500' - 1500' |
| Friday |
Snow Level 500' - 2500' (Easterly Flow *) |
| Friday Night |
Snow Level 2000' - 3000' |
| Saturday |
Snow 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 Jan 7, 2020
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