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 & Saturday
A weak shortwave that passed through in NW flow aloft produced a few inches (up to 7 inches at Stevens Pass) of snow overnight and early Wednesday morning along the west slopes of the Cascades. Scattered showers will continue mainly along the west slopes, Mt. Hood and the north slopes of the Olympics through mid-day with sunnier skies along the east slopes.
The next incoming Pacific frontal system will be more powerful. Mid and high clouds will spread over the PNW tonight with moderate snow developing for Mt. Hood Thursday morning. The heaviest precipitation should be for the south Washington Cascades and Mt. Hood area during the day Thursday. Warm air will work it's way into the Mt. Hood area and the Olympics, causing a switch to rain at lower and mid-elevations by Thursday afternoon.
The frontal boundary should temporarily stall late Thursday afternoon. As a secondary wave develops along the frontal boundary, the developing surface low pressure system should track NE across western Washington and push the front through the Cascades Thursday night, helping spread heavier precipitation further north. Snow levels in the Crystal/Paradise area should briefly rise to around 4500-5000 feet Thursday night, but areas further north and east should remain cooler.
Weather Forecast
Olympics, Washington Cascades near and west of the crest including Stevens, Snoqualmie, and White Passes
| Wednesday Morning |
Mostly cloudy with scattered light showers along the west slopes of the Cascades and the north slopes of the Olympics. |
| Wednesday Afternoon - Wednesday Night |
Partly cloudy with isolated showers. Increasing high clouds overnight with light snow developing late overnight Olympics and south Washington Cascades. |
| Thursday |
Light snow in the north Cascades and Olympics and moderate rain and snow in the central and south Washington Cascades. Warming trend Olympics and far south Washington Cascades. |
| Thursday Night |
Moderate to occasionally heavy rain and snow becoming showers late overnight. Slight warming trend south and central Washington Cascades away from the Passes. |
East slopes of the Washington Cascades
| Wednesday Morning |
Partly cloudy with scattered light showers near the Cascade crest. |
| Wednesday Afternoon - Wednesday Night |
Mostly clear. |
| Thursday |
Light snow in the northeast Cascades and light to moderate snow in the central and southeast Washington Cascades. |
| Thursday Night |
Moderate rain and snow becoming showers late overnight. |
Mt. Hood Area
| Wednesday |
Mostly cloudy with scattered light showers in the morning. Partly cloudy with isolated showers in the afternoon. |
| Wednesday Afternoon - Wednesday Night |
Increasing high clouds Wednesday evening with moderate rain and snow developing overnight. |
| Thursday - Thursday Night |
Stormy with moderate to heavy rain and snow. Strong warming trend through the day. Increasing winds in the afternoon. |
Issued: 2:48 PM PST Wednesday, December 16, 2015
Snow/Freezing Level (ft)
| Hurricane Ridge | Mt. Baker | Washington Pass | Leavenworth | Stevens Pass | Snoqualmie Pass | Mt. Rainier, Crystal & White Pass | Mt. Hood | ||
|---|---|---|---|---|---|---|---|---|---|
| Wednesday - Wednesday Night | Snow Level | 2500' | 1000' | 0' | ' | ' | 2000' | ' | 3000' |
| Thursday Morning | Snow Level * | 3000' | 1500' | 500' | ' | ' | 1000' | ' | 3000' |
| Thursday Mid-day | Snow Level * | 4000' | 1500' | 1000' | ' | ' | 1500' | ' | 4500' |
| Thursday Afternoon - Thursday Evening | Snow Level * | 6000' | 2500' | 1000' | ' | ' | 2000' | ' | 7000' |
| Thursday Night | Snow Level * | 5500' | 3000' | 1500' | ' | ' | 3500' | ' | 6500' |
| Hurricane Ridge | Elevation |
|---|---|
| Wednesday - Wednesday Night |
Snow Level 2500' |
| Thursday Morning |
Snow Level 3000' (Easterly Flow *) |
| Thursday Mid-day |
Snow Level 4000' (Easterly Flow *) |
| Thursday Afternoon - Thursday Evening |
Snow Level 6000' (Easterly Flow *) |
| Thursday Night |
Snow Level 5500' (Easterly Flow *) |
| Mt. Baker | Elevation |
|---|---|
| Wednesday - Wednesday Night |
Snow Level 1000' |
| Thursday Morning |
Snow Level 1500' (Easterly Flow *) |
| Thursday Mid-day |
Snow Level 1500' (Easterly Flow *) |
| Thursday Afternoon - Thursday Evening |
Snow Level 2500' (Easterly Flow *) |
| Thursday Night |
Snow Level 3000' (Easterly Flow *) |
| Washington Pass | Elevation |
|---|---|
| Wednesday - Wednesday Night |
Snow Level 0' |
| Thursday Morning |
Snow Level 500' (Easterly Flow *) |
| Thursday Mid-day |
Snow Level 1000' (Easterly Flow *) |
| Thursday Afternoon - Thursday Evening |
Snow Level 1000' (Easterly Flow *) |
| Thursday Night |
Snow Level 1500' (Easterly Flow *) |
| Leavenworth | Elevation |
|---|---|
| Wednesday - Wednesday Night |
Snow Level ' |
| Thursday Morning |
Snow Level ' (Easterly Flow *) |
| Thursday Mid-day |
Snow Level ' (Easterly Flow *) |
| Thursday Afternoon - Thursday Evening |
Snow Level ' (Easterly Flow *) |
| Thursday Night |
Snow Level ' (Easterly Flow *) |
| Stevens Pass | Elevation |
|---|---|
| Wednesday - Wednesday Night |
Snow Level ' |
| Thursday Morning |
Snow Level ' (Easterly Flow *) |
| Thursday Mid-day |
Snow Level ' (Easterly Flow *) |
| Thursday Afternoon - Thursday Evening |
Snow Level ' (Easterly Flow *) |
| Thursday Night |
Snow Level ' (Easterly Flow *) |
| Snoqualmie Pass | Elevation |
|---|---|
| Wednesday - Wednesday Night |
Snow Level 2000' |
| Thursday Morning |
Snow Level 1000' (Easterly Flow *) |
| Thursday Mid-day |
Snow Level 1500' (Easterly Flow *) |
| Thursday Afternoon - Thursday Evening |
Snow Level 2000' (Easterly Flow *) |
| Thursday Night |
Snow Level 3500' (Easterly Flow *) |
| Mt. Rainier & Crystal | Elevation |
|---|---|
| Wednesday - Wednesday Night |
Snow Level ' |
| Thursday Morning |
Snow Level ' (Easterly Flow *) |
| Thursday Mid-day |
Snow Level ' (Easterly Flow *) |
| Thursday Afternoon - Thursday Evening |
Snow Level ' (Easterly Flow *) |
| Thursday Night |
Snow Level ' (Easterly Flow *) |
| Mt. Hood | Elevation |
|---|---|
| Wednesday - Wednesday Night |
Snow Level 3000' |
| Thursday Morning |
Snow Level 3000' (Easterly Flow *) |
| Thursday Mid-day |
Snow Level 4500' (Easterly Flow *) |
| Thursday Afternoon - Thursday Evening |
Snow Level 7000' (Easterly Flow *) |
| Thursday Night |
Snow Level 6500' (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
| Saturday | Saturday | |
|---|---|---|
| Hurricane Ridge | LT 0.25 | 0 - 0.75 |
| Mt Baker Ski Area | LT 0.10 | 1.00 - 1.50 |
| Washington Pass | LT 0.10 | 0.75 - 1.00 |
| Stevens Pass | LT 0.10 | 0 - 1.50 |
| Snoqualmie Pass | LT 0.25 | 0 - 2.00 |
| Mission Ridge | LT 0.10 | 0 - 1.00 |
| Crystal Mt | LT 0.25 | 0 - 2.00 |
| Paradise | LT 0.25 | 2.50 - 3.50 |
| White Pass | LT 0.25 | 0 - 1.50 |
| Mt Hood Meadows | 0 - 0.75 | 3.00 - 4.00 |
| Timberline | 0 - 1.00 | 3.50 - 4.50 |
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: 2:48 PM PST Wednesday, December 16, 2015
Free Winds at 5000' (mph)
| Hurricane Ridge | Mt. Baker | Stevens to Snoqualmie Pass | Mt. Rainier | Mt. Hood | |
|---|---|---|---|---|---|
| Wednesday Afternoon | SE 5 - 15 | E 0 - 10 | E 0 - 10 | --- - | W 0 - 10 |
| Wednesday Night - Thursday Morning | SE 10 - 20 | ESE 5 - 15 | SE 10 - 20 | --- - | SE 10 - 20 |
| Thursday Afternoon | S 5 - 15 | ESE 5 - 15 | SE 10 - 20 | --- - | SW 30 - 40 |
| Thursday Night | S 10 - 20 | SE 10 - 20 | SE 15 - 25 | --- - | SW 45 - 55 |
| Hurricane Ridge | Elevation |
|---|---|
| Wednesday Afternoon | SE 5 - 15 |
| Wednesday Night - Thursday Morning | SE 10 - 20 |
| Thursday Afternoon | S 5 - 15 |
| Thursday Night | S 10 - 20 |
| Mt. Baker | Elevation |
|---|---|
| Wednesday Afternoon | E 0 - 10 |
| Wednesday Night - Thursday Morning | ESE 5 - 15 |
| Thursday Afternoon | ESE 5 - 15 |
| Thursday Night | SE 10 - 20 |
| Stevens and Snoqualmie Pass | Elevation |
|---|---|
| Wednesday Afternoon | E 0 - 10 |
| Wednesday Night - Thursday Morning | SE 10 - 20 |
| Thursday Afternoon | SE 10 - 20 |
| Thursday Night | SE 15 - 25 |
| Mt. Rainier | Elevation |
|---|---|
| Wednesday Afternoon | --- - |
| Wednesday Night - Thursday Morning | --- - |
| Thursday Afternoon | --- - |
| Thursday Night | --- - |
| Mt. Hood | Elevation |
|---|---|
| Wednesday Afternoon | W 0 - 10 |
| Wednesday Night - Thursday Morning | SE 10 - 20 |
| Thursday Afternoon | SW 30 - 40 |
| Thursday Night | SW 45 - 55 |
| Hurricane Ridge | Direction - Speed |
|---|---|
| Wednesday Afternoon | SE 5 - 15 |
| Wednesday Night - Thursday Morning | SE 10 - 20 |
| Thursday Afternoon | S 5 - 15 |
| Thursday Night | S 10 - 20 |
| Mt. Baker | Direction - Speed |
|---|---|
| Wednesday Afternoon | E 0 - 10 |
| Wednesday Night - Thursday Morning | ESE 5 - 15 |
| Thursday Afternoon | ESE 5 - 15 |
| Thursday Night | SE 10 - 20 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Wednesday Afternoon | E 0 - 10 |
| Wednesday Night - Thursday Morning | SE 10 - 20 |
| Thursday Afternoon | SE 10 - 20 |
| Thursday Night | SE 15 - 25 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Wednesday Afternoon | --- - |
| Wednesday Night - Thursday Morning | --- - |
| Thursday Afternoon | --- - |
| Thursday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| Wednesday Afternoon | W 0 - 10 |
| Wednesday Night - Thursday Morning | SE 10 - 20 |
| Thursday Afternoon | SW 30 - 40 |
| Thursday Night | SW 45 - 55 |
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 Afternoon | NE 10 - 20 | N 10 - 20 | NNE 10 - 20 | --- - | NW 15 - 25 |
| Wednesday Night - Thursday Morning | S 10 - 20 | S 10 - 20 | SW 15 - 25 | --- - | WSW 40 - 50 |
| Thursday Afternoon | SW 15 - 25 | SW 10 - 20 | SW 30 - 40 | --- - | WSW 40 - 50 |
| Thursday Night | SW 35 - 45 | SSW 25 - 35 | SW 40 - 50 | --- - | WSW 60 - 80 |
| Mt. Baker | Direction - Speed |
|---|---|
| Wednesday Afternoon | NE 10 - 20 |
| Wednesday Night - Thursday Morning | S 10 - 20 |
| Thursday Afternoon | SW 15 - 25 |
| Thursday Night | SW 35 - 45 |
| Washington Pass | Direction - Speed |
|---|---|
| Wednesday Afternoon | N 10 - 20 |
| Wednesday Night - Thursday Morning | S 10 - 20 |
| Thursday Afternoon | SW 10 - 20 |
| Thursday Night | SSW 25 - 35 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Wednesday Afternoon | NNE 10 - 20 |
| Wednesday Night - Thursday Morning | SW 15 - 25 |
| Thursday Afternoon | SW 30 - 40 |
| Thursday Night | SW 40 - 50 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Wednesday Afternoon | --- - |
| Wednesday Night - Thursday Morning | --- - |
| Thursday Afternoon | --- - |
| Thursday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| Wednesday Afternoon | NW 15 - 25 |
| Wednesday Night - Thursday Morning | WSW 40 - 50 |
| Thursday Afternoon | WSW 40 - 50 |
| Thursday Night | WSW 60 - 80 |
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: 2:48 PM PST Wednesday, December 16, 2015
Extended Weather Synopsis for Saturday night through Saturday
A switch to westerly flow Friday morning should briefly bump up snow levels to around 4000 feet in the Cascade Passes. A cooler more homogeneous air mass will settle in over the area Friday afternoon with post-frontal showers mainly along the west slopes.
Light showers and cool snow levels will continue through Saturday as the longwave trough axis passes through. The next frontal system should arrive Saturday night and stay relatively cool throughout the event. Steady precipitation should transition to showers during the day Sunday. It looks like the snowy pattern with systems crossing the area in cool NW flow aloft will continue well into next week.
Extended Weather
Olympics, Washington Cascades and Mt. Hood Area
Light to moderate rain and snow showers, heaviest west slopes of the Cascades. Brief warming trend Cascade Passes with a switch to west winds.
Mostly cloudy with light rain and snow showers.
Partly to mostly cloudy with scattered light snow showers. Steady snow developing Olympics Saturday afternoon.
Moderate snow, except occasionally heavy west slopes of the Washington Cascades.
Mostly cloudy with light to moderate showers.
Extended Snow/Freezing Levels
| Mt. Baker | Snoqualmie Pass | Mt. Hood | Easterly Flow * | ||
|---|---|---|---|---|---|
| Friday Morning | Snow Level | 2500' - 3500' | 3500' - 4500' | 4500' - 5500' | |
| Friday Afternoon | Snow Level | 2000' - 3000' | 2000' - 3000' | 2500' - 3500' | * |
| Friday Night - Saturday | Snow Level | 1500' - 2500' | 1500' - 2500' | 1500' - 2500' | * |
| Saturday Night - Sunday | Snow Level | 2000' - 3000' | 2000' - 3000' | 2000' - 3000' |
| Mt. Baker | Elevation |
|---|---|
| Friday Morning |
Snow Level 2500' - 3500' |
| Friday Afternoon |
Snow Level 2000' - 3000' (Easterly Flow *) |
| Friday Night - Saturday |
Snow Level 1500' - 2500' (Easterly Flow *) |
| Saturday Night - Sunday |
Snow Level 2000' - 3000' |
| Snoqualmie Pass | Elevation |
|---|---|
| Friday Morning |
Snow Level 3500' - 4500' |
| Friday Afternoon |
Snow Level 2000' - 3000' (Easterly Flow *) |
| Friday Night - Saturday |
Snow Level 1500' - 2500' (Easterly Flow *) |
| Saturday Night - Sunday |
Snow Level 2000' - 3000' |
| Mt. Hood | Elevation |
|---|---|
| Friday Morning |
Snow Level 4500' - 5500' |
| Friday Afternoon |
Snow Level 2500' - 3500' (Easterly Flow *) |
| Friday Night - Saturday |
Snow Level 1500' - 2500' (Easterly Flow *) |
| Saturday Night - Sunday |
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 Dec 16, 2015
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