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 & Tuesday
A frontal system currently off the Washington Coast is pushing light to moderate bands of precipitation inland Thursday afternoon. Snow levels should stay steady at moderate levels and with cool easterly flow in the Cascade passes...this should be a light to moderate snow event for most areas with the heaviest accumulations on the volcanoes.
A weak ridge should build on Friday with leftover showers for the mountains and light additional accumulations.
The jet stream over the eastern Pacific will become more consolidated and quite strong leading into the weekend...preparing a series of strong and wet weather systems for our area.
Note: Avalanche forecasts will begin on Friday, Dec 19th.
Weather Forecast
Olympics, Washington Cascades near and west of the crest including Stevens, Snoqualmie, and White Passes and Mt. Hood
| Thursday Afternoon - Thursday Night |
Light to moderate rain and snow, heaviest volcanoes. |
| Friday - Friday Evening |
Mostly cloudy with light to occasionally moderate rain and snow showers. |
| Friday Night |
Light to moderate rain and snow spreading into the Olympics...light rain and snow Cascades and Mt. Hood. |
Olympics, Washington Cascades near and west of the crest including Stevens, Snoqualmie, and White Passes and Mt. Hood
| Thursday Afternoon - Thursday Night |
Light rain and snow. |
| Friday - Friday Night |
Mostly cloudy with light rain and snow showers. |
Issued: 1:12 PM PST Thursday, December 18, 2014
Snow/Freezing Level (ft)
| Hurricane Ridge | Mt. Baker | Washington Pass | Leavenworth | Stevens Pass | Snoqualmie Pass | Mt. Rainier, Crystal & White Pass | Mt. Hood | ||
|---|---|---|---|---|---|---|---|---|---|
| Thursday Afternoon - Thursday Evening | Snow Level * | 5500' | 4500' | 3500' | ' | ' | 4000' | ' | 5500' |
| Thursday Night | Snow Level * | 4000' | 4000' | 3500' | ' | ' | 4000' | ' | 4500' |
| Friday | Snow Level | 3500' | 3000' | 3000' | ' | ' | 3500' | ' | 4000' |
| Friday Night | Snow Level * | 4000' | 3000' | 2500' | ' | ' | 3000' | ' | 4000' |
| Hurricane Ridge | Elevation |
|---|---|
| Thursday Afternoon - Thursday Evening |
Snow Level 5500' (Easterly Flow *) |
| Thursday Night |
Snow Level 4000' (Easterly Flow *) |
| Friday |
Snow Level 3500' |
| Friday Night |
Snow Level 4000' (Easterly Flow *) |
| Mt. Baker | Elevation |
|---|---|
| Thursday Afternoon - Thursday Evening |
Snow Level 4500' (Easterly Flow *) |
| Thursday Night |
Snow Level 4000' (Easterly Flow *) |
| Friday |
Snow Level 3000' |
| Friday Night |
Snow Level 3000' (Easterly Flow *) |
| Washington Pass | Elevation |
|---|---|
| Thursday Afternoon - Thursday Evening |
Snow Level 3500' (Easterly Flow *) |
| Thursday Night |
Snow Level 3500' (Easterly Flow *) |
| Friday |
Snow Level 3000' |
| Friday Night |
Snow Level 2500' (Easterly Flow *) |
| Leavenworth | Elevation |
|---|---|
| Thursday Afternoon - Thursday Evening |
Snow Level ' (Easterly Flow *) |
| Thursday Night |
Snow Level ' (Easterly Flow *) |
| Friday |
Snow Level ' |
| Friday Night |
Snow Level ' (Easterly Flow *) |
| Stevens Pass | Elevation |
|---|---|
| Thursday Afternoon - Thursday Evening |
Snow Level ' (Easterly Flow *) |
| Thursday Night |
Snow Level ' (Easterly Flow *) |
| Friday |
Snow Level ' |
| Friday Night |
Snow Level ' (Easterly Flow *) |
| Snoqualmie Pass | Elevation |
|---|---|
| Thursday Afternoon - Thursday Evening |
Snow Level 4000' (Easterly Flow *) |
| Thursday Night |
Snow Level 4000' (Easterly Flow *) |
| Friday |
Snow Level 3500' |
| Friday Night |
Snow Level 3000' (Easterly Flow *) |
| Mt. Rainier & Crystal | Elevation |
|---|---|
| Thursday Afternoon - Thursday Evening |
Snow Level ' (Easterly Flow *) |
| Thursday Night |
Snow Level ' (Easterly Flow *) |
| Friday |
Snow Level ' |
| Friday Night |
Snow Level ' (Easterly Flow *) |
| Mt. Hood | Elevation |
|---|---|
| Thursday Afternoon - Thursday Evening |
Snow Level 5500' (Easterly Flow *) |
| Thursday Night |
Snow Level 4500' (Easterly Flow *) |
| Friday |
Snow Level 4000' |
| Friday Night |
Snow Level 4000' (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
| Tuesday | Tuesday | |
|---|---|---|
| Hurricane Ridge | 0 - 0.50 | LT 0.25 |
| Mt Baker Ski Area | 0 - 1.50 | 0.50 - 0.75 |
| Washington Pass | 0.25 - 0.50 | LT 0.25 |
| Stevens Pass | 0 - 0.50 | LT 0.25 |
| Snoqualmie Pass | 0 - 0.75 | LT 0.25 |
| Mission Ridge | LT 0.25 | LT 0.10 |
| Crystal Mt | 0 - 0.75 | LT 0.25 |
| Paradise | 1.00 - 1.50 | 0 - 0.50 |
| White Pass | 0.25 - 0.50 | LT 0.25 |
| Mt Hood Meadows | 0 - 1.00 | 0.25 - 0.50 |
| Timberline | 1.00 - 1.50 | 0.50 - 0.75 |
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: 1:12 PM PST Thursday, December 18, 2014
Free Winds at 5000' (mph)
| Hurricane Ridge | Mt. Baker | Stevens to Snoqualmie Pass | Mt. Rainier | Mt. Hood | |
|---|---|---|---|---|---|
| Thursday Afternoon | SW 20 - 30 | S 10 - 20 | SW 10 - 20 | --- - | SW 10 - 20 |
| Thursday Night | SW 15 - 25 | SW 15 - 25 | SW 15 - 25 | --- - | WSW 15 - 25 |
| Friday | SW 15 - 25 | SW 10 - 20 | SW 10 - 20 | --- - | WSW 10 - 20 |
| Friday Night | S 20 - 30 | S 10 - 20 | SE 10 - 20 | --- - | SW 15 - 25 |
| Hurricane Ridge | Elevation |
|---|---|
| Thursday Afternoon | SW 20 - 30 |
| Thursday Night | SW 15 - 25 |
| Friday | SW 15 - 25 |
| Friday Night | S 20 - 30 |
| Mt. Baker | Elevation |
|---|---|
| Thursday Afternoon | S 10 - 20 |
| Thursday Night | SW 15 - 25 |
| Friday | SW 10 - 20 |
| Friday Night | S 10 - 20 |
| Stevens and Snoqualmie Pass | Elevation |
|---|---|
| Thursday Afternoon | SW 10 - 20 |
| Thursday Night | SW 15 - 25 |
| Friday | SW 10 - 20 |
| Friday Night | SE 10 - 20 |
| Mt. Rainier | Elevation |
|---|---|
| Thursday Afternoon | --- - |
| Thursday Night | --- - |
| Friday | --- - |
| Friday Night | --- - |
| Mt. Hood | Elevation |
|---|---|
| Thursday Afternoon | SW 10 - 20 |
| Thursday Night | WSW 15 - 25 |
| Friday | WSW 10 - 20 |
| Friday Night | SW 15 - 25 |
| Hurricane Ridge | Direction - Speed |
|---|---|
| Thursday Afternoon | SW 20 - 30 |
| Thursday Night | SW 15 - 25 |
| Friday | SW 15 - 25 |
| Friday Night | S 20 - 30 |
| Mt. Baker | Direction - Speed |
|---|---|
| Thursday Afternoon | S 10 - 20 |
| Thursday Night | SW 15 - 25 |
| Friday | SW 10 - 20 |
| Friday Night | S 10 - 20 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Thursday Afternoon | SW 10 - 20 |
| Thursday Night | SW 15 - 25 |
| Friday | SW 10 - 20 |
| Friday Night | SE 10 - 20 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Thursday Afternoon | --- - |
| Thursday Night | --- - |
| Friday | --- - |
| Friday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| Thursday Afternoon | SW 10 - 20 |
| Thursday Night | WSW 15 - 25 |
| Friday | WSW 10 - 20 |
| 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 25 - 35 | WSW 20 - 30 | SW 25 - 35 | --- - | SW 30 - 40 |
| Thursday Night | SW 25 - 35 | SW 15 - 25 | SW 25 - 35 | --- - | SW 25 - 35 |
| Friday | SW 15 - 25 | W 15 - 25 | WSW 20 - 30 | --- - | WSW 25 - 35 |
| Friday Night | SW 20 - 30 | SW 10 - 20 | SW 25 - 35 | --- - | SW 25 - 35 |
| Mt. Baker | Direction - Speed |
|---|---|
| Thursday Afternoon | SW 25 - 35 |
| Thursday Night | SW 25 - 35 |
| Friday | SW 15 - 25 |
| Friday Night | SW 20 - 30 |
| Washington Pass | Direction - Speed |
|---|---|
| Thursday Afternoon | WSW 20 - 30 |
| Thursday Night | SW 15 - 25 |
| Friday | W 15 - 25 |
| Friday Night | SW 10 - 20 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Thursday Afternoon | SW 25 - 35 |
| Thursday Night | SW 25 - 35 |
| Friday | WSW 20 - 30 |
| Friday Night | SW 25 - 35 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Thursday Afternoon | --- - |
| Thursday Night | --- - |
| Friday | --- - |
| Friday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| Thursday Afternoon | SW 30 - 40 |
| Thursday Night | SW 25 - 35 |
| Friday | WSW 25 - 35 |
| Friday Night | SW 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.
Issued: 1:12 PM PST Thursday, December 18, 2014
Extended Weather Synopsis for Tuesday night through Tuesday
Get ready for a wet and wild weekend...in terms of weather of course. The aforementioned very strong westerly jet stream will send at least 2 pulses of heavy precipitation into our area. The first will arrive on Saturday...with precipitation becoming heavy in the Cascades by mid-day. Initial easterly flow through the Cascade Passes should translate into snow even as warm air rides in aloft. A switch to rain in the Passes will likely happen mid-day or late Saturday afternoon.
The strongest warming should occur Saturday afternoon through Saturday night and settle at these moderately high levels through Sunday keeping rain in the low to moderate elevations and wet snow at higher elevations. Strong westerly flow aloft will translate into stormy conditions for the mountains, with the secondary pulse arriving sometime Sunday. Precipitation could be very heavy for the south Cascades and Mt. Hood area Sunday.
Precipitation may ease on Monday...there is poor forecast model agreement but in any case there does not seem to be much cooling as an upper level ridge off the southern CA coast strengthens and maintains warm air aloft over the region.
Extended Weather
Washington Cascades near and west of the crest including Stevens, Snoqualmie, and White Passes and Mt. Hood
Light to moderate rain and snow increasing through mid-day.
Stormy periods with moderate to heavy rain and snow. Warming trend. Precipitation could be very heavy south Washington Cascades and Mt. Hood area Sunday.
Light to moderate rain and snow. Mild.
Extended Snow/Freezing Levels
| Mt. Baker | Snoqualmie Pass | Mt. Hood | Easterly Flow * | ||
|---|---|---|---|---|---|
| Saturday Morning - Saturday Mid-day | Snow Level | 2500' - 3500' | 2500' - 3500' | 4000' - 5000' | * |
| Saturday Afternoon | Snow Level | 4000' - 5000' | 5000' - 6500' | 7000' - 8000' | |
| Saturday Night | Snow Level | 4500' - 5500' | 5500' - 6500' | 7500' - 8500' | |
| Sunday | Snow Level | 5000' - 6000' | 6000' - 7000' | 7500' - 8500' | |
| Monday | Snow Level | 3500' - 4500' | 3500' - 4500' | 5500' - 6500' |
| Mt. Baker | Elevation |
|---|---|
| Saturday Morning - Saturday Mid-day |
Snow Level 2500' - 3500' (Easterly Flow *) |
| Saturday Afternoon |
Snow Level 4000' - 5000' |
| Saturday Night |
Snow Level 4500' - 5500' |
| Sunday |
Snow Level 5000' - 6000' |
| Monday |
Snow Level 3500' - 4500' |
| Snoqualmie Pass | Elevation |
|---|---|
| Saturday Morning - Saturday Mid-day |
Snow Level 2500' - 3500' (Easterly Flow *) |
| Saturday Afternoon |
Snow Level 5000' - 6500' |
| Saturday Night |
Snow Level 5500' - 6500' |
| Sunday |
Snow Level 6000' - 7000' |
| Monday |
Snow Level 3500' - 4500' |
| Mt. Hood | Elevation |
|---|---|
| Saturday Morning - Saturday Mid-day |
Snow Level 4000' - 5000' (Easterly Flow *) |
| Saturday Afternoon |
Snow Level 7000' - 8000' |
| Saturday Night |
Snow Level 7500' - 8500' |
| Sunday |
Snow Level 7500' - 8500' |
| Monday |
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 Apr 26, 2014
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