Jump to: Weather Forecast I Snow/Freezing Level I Precipitation I Free Winds 5k I Free Winds 9k I Extended Weather
Weather Synopsis for Sunday night through Thursday
The weather pattern is unusually quiet this week for December. On Sunday afternoon, the Pacific Northwest sits near the western edge of a broad trough with a weak and narrow ridge approximately 500 miles offshore. The cool air mass in place is continuing to spawn isolated snow showers under weakly stable atmosphere conditions. As the low pressure system currently over Idaho moves farther away from the forecast area, atmospheric stability will return, cutting off the snow showers and decreasing cloud cover during the overnight hours on Sunday. Weak low-level offshore flow will also begin to develop.
The broad upper level low pressure will gradually move east on Monday and Monday night and with northerly flow in place, temperatures will remain dry and cool and low level easterly flow will gradually increase.
Monday and Monday night, a low cuts off fully from the northern branch of the jetstream and drops southward toward California, with a high pressure system remaining to the north. This high over low configuration blocks incoming weather to our region and will leave us dry.
Tuesday will remain dry as the high pressure offshore will edge into our region, bringing warmer temperatures west of the Cascade Crest, while cold air will remain east of the Cascade Crest, driving light to moderate easterly flow through the passes.
Weather Forecast
Hurricane Ridge
| Sunday Night | Mostly clear with light winds. |
| Monday | Mostly sunny with light winds. |
Mt. Baker
| Sunday Night | Mostly clear with light winds. |
| Monday | Sunny skies and light winds. |
Stevens and Snoqualmie Pass
| Sunday Night | Partly cloudy with a chance of an isolated snow flurry early; becoming isolated cloud-cover with light easterly flow developing after midnight. |
| Monday | Low-level clouds east of the Cascade Crest. |
Mt. Rainier and Crystal
| Sunday Night | Partly cloudy with a chance of an isolated snow flurry early; becoming isolated cloud-cover with light easterly flow developing after midnight. |
| Monday | Low-level clouds east of the Cascade Crest. Light easterly flow. |
Washington Pass and Leavenworth
| Sunday Night | Chance of an isolated snow flurry early in the south. Becoming mostly clear with light winds. Light easterly flow developing after midnight. |
| Monday | Low-level clouds. Light easterly flow. |
Mt. Hood
| Sunday Night | Partly cloudy with snow flurries early; isolated cloud-cover after midnight and light easterly flow increasing. |
| Monday | Mostly sunny with isolated low clouds and light easterly flow. |
Issued: 2:38 PM PST Sunday, December 2, 2018
Snow/Freezing Level (ft)
| Hurricane Ridge | Mt. Baker | Washington Pass | Leavenworth | Stevens Pass | Snoqualmie Pass | Mt. Rainier, Crystal & White Pass | Mt. Hood | ||
|---|---|---|---|---|---|---|---|---|---|
| Sunday Evening | Snow Level | 1500' | 1000' | 0' | 500' | 500' | 500' | 1000' | 1000' |
| Sunday Night | Freezing Level * | 2000' | 2000' | 0' | 1000' | 0' | 1000' | 1000' | 1000' |
| Monday Morning | Freezing Level * | 2500' | 2500' | 1500' | 1700' | 1500' | 2500' | 3000' | 2500' |
| Monday Afternoon | Freezing Level * | 3500' | 3500' | 2500' | 2500' | 2500' | 2500' | 3500' | 3500' |
| Monday Evening | Freezing Level * | 2500' | 2500' | 1000' | 1500' | 2000' | 2000' | 2500' | 2500' |
| Monday Night | Freezing Level * | 2000' | 2500' | 1000' | 1000' | 1000' | 1500' | 1000' | 2500' |
| Tuesday Morning | Freezing Level * | 4500' | 3000' | 2000' | 1500' | 1500' | 2000' | 3000' | 2000' |
| Tuesday Afternoon | Freezing Level * | 6000' | 4000' | 3500' | 2500' | 2500' | 3500' | 4000' | 3500' |
| Hurricane Ridge | Elevation |
|---|---|
| Sunday Evening |
Snow Level 1500' |
| Sunday Night |
Freezing Level 2000' (Easterly Flow *) |
| Monday Morning |
Freezing Level 2500' (Easterly Flow *) |
| Monday Afternoon |
Freezing Level 3500' (Easterly Flow *) |
| Monday Evening |
Freezing Level 2500' (Easterly Flow *) |
| Monday Night |
Freezing Level 2000' (Easterly Flow *) |
| Tuesday Morning |
Freezing Level 4500' (Easterly Flow *) |
| Tuesday Afternoon |
Freezing Level 6000' (Easterly Flow *) |
| Mt. Baker | Elevation |
|---|---|
| Sunday Evening |
Snow Level 1000' |
| Sunday Night |
Freezing Level 2000' (Easterly Flow *) |
| Monday Morning |
Freezing Level 2500' (Easterly Flow *) |
| Monday Afternoon |
Freezing Level 3500' (Easterly Flow *) |
| Monday Evening |
Freezing Level 2500' (Easterly Flow *) |
| Monday Night |
Freezing Level 2500' (Easterly Flow *) |
| Tuesday Morning |
Freezing Level 3000' (Easterly Flow *) |
| Tuesday Afternoon |
Freezing Level 4000' (Easterly Flow *) |
| Washington Pass | Elevation |
|---|---|
| Sunday Evening |
Snow Level 0' |
| Sunday Night |
Freezing Level 0' (Easterly Flow *) |
| Monday Morning |
Freezing Level 1500' (Easterly Flow *) |
| Monday Afternoon |
Freezing Level 2500' (Easterly Flow *) |
| Monday Evening |
Freezing Level 1000' (Easterly Flow *) |
| Monday Night |
Freezing Level 1000' (Easterly Flow *) |
| Tuesday Morning |
Freezing Level 2000' (Easterly Flow *) |
| Tuesday Afternoon |
Freezing Level 3500' (Easterly Flow *) |
| Leavenworth | Elevation |
|---|---|
| Sunday Evening |
Snow Level 500' |
| Sunday Night |
Freezing Level 1000' (Easterly Flow *) |
| Monday Morning |
Freezing Level 1700' (Easterly Flow *) |
| Monday Afternoon |
Freezing Level 2500' (Easterly Flow *) |
| Monday Evening |
Freezing Level 1500' (Easterly Flow *) |
| Monday Night |
Freezing Level 1000' (Easterly Flow *) |
| Tuesday Morning |
Freezing Level 1500' (Easterly Flow *) |
| Tuesday Afternoon |
Freezing Level 2500' (Easterly Flow *) |
| Stevens Pass | Elevation |
|---|---|
| Sunday Evening |
Snow Level 500' |
| Sunday Night |
Freezing Level 0' (Easterly Flow *) |
| Monday Morning |
Freezing Level 1500' (Easterly Flow *) |
| Monday Afternoon |
Freezing Level 2500' (Easterly Flow *) |
| Monday Evening |
Freezing Level 2000' (Easterly Flow *) |
| Monday Night |
Freezing Level 1000' (Easterly Flow *) |
| Tuesday Morning |
Freezing Level 1500' (Easterly Flow *) |
| Tuesday Afternoon |
Freezing Level 2500' (Easterly Flow *) |
| Snoqualmie Pass | Elevation |
|---|---|
| Sunday Evening |
Snow Level 500' |
| Sunday Night |
Freezing Level 1000' (Easterly Flow *) |
| Monday Morning |
Freezing Level 2500' (Easterly Flow *) |
| Monday Afternoon |
Freezing Level 2500' (Easterly Flow *) |
| Monday Evening |
Freezing Level 2000' (Easterly Flow *) |
| Monday Night |
Freezing Level 1500' (Easterly Flow *) |
| Tuesday Morning |
Freezing Level 2000' (Easterly Flow *) |
| Tuesday Afternoon |
Freezing Level 3500' (Easterly Flow *) |
| Mt. Rainier & Crystal | Elevation |
|---|---|
| Sunday Evening |
Snow Level 1000' |
| Sunday Night |
Freezing Level 1000' (Easterly Flow *) |
| Monday Morning |
Freezing Level 3000' (Easterly Flow *) |
| Monday Afternoon |
Freezing Level 3500' (Easterly Flow *) |
| Monday Evening |
Freezing Level 2500' (Easterly Flow *) |
| Monday Night |
Freezing Level 1000' (Easterly Flow *) |
| Tuesday Morning |
Freezing Level 3000' (Easterly Flow *) |
| Tuesday Afternoon |
Freezing Level 4000' (Easterly Flow *) |
| Mt. Hood | Elevation |
|---|---|
| Sunday Evening |
Snow Level 1000' |
| Sunday Night |
Freezing Level 1000' (Easterly Flow *) |
| Monday Morning |
Freezing Level 2500' (Easterly Flow *) |
| Monday Afternoon |
Freezing Level 3500' (Easterly Flow *) |
| Monday Evening |
Freezing Level 2500' (Easterly Flow *) |
| Monday Night |
Freezing Level 2500' (Easterly Flow *) |
| Tuesday Morning |
Freezing Level 2000' (Easterly Flow *) |
| Tuesday Afternoon |
Freezing Level 3500' (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
| Sunday Night | Thursday | Thursday Night | Thursday | |
|---|---|---|---|---|
| 4 pm - 4 am | 4 am - 4 pm | 4 pm - 4 am | 4 am - 4 pm | |
| Hurricane Ridge | 0 | 0 | 0 | 0 |
| Mt Baker Ski Area | 0 | 0 | 0 | 0 |
| Washington Pass | 0 | 0 | 0 | 0 |
| Stevens Pass | 0 | 0 | 0 | 0 |
| Snoqualmie Pass | 0 | 0 | 0 | 0 |
| Leavenworth | 0 | 0 | 0 | 0 |
| Mission Ridge | 0 | 0 | 0 | 0 |
| Crystal Mt | LT 0.10 | 0 | 0 | 0 |
| Paradise | 0 | 0 | 0 | 0 |
| White Pass | 0 | 0 | 0 | 0 |
| Mt Hood Meadows | LT 0.10 | 0 | 0 | 0 |
| Timberline | LT 0.10 | 0 | 0 | 0 |
| Hurricane Ridge | Precipitation Forecast |
|---|---|
| Sunday Night | 0 |
| Thursday | 0 |
| Thursday Night | 0 |
| Thursday | 0 |
| Mt Baker Ski Area | Precipitation Forecast |
|---|---|
| Sunday Night | 0 |
| Thursday | 0 |
| Thursday Night | 0 |
| Thursday | 0 |
| Washington Pass | Precipitation Forecast |
|---|---|
| Sunday Night | 0 |
| Thursday | 0 |
| Thursday Night | 0 |
| Thursday | 0 |
| Stevens Pass | Precipitation Forecast |
|---|---|
| Sunday Night | 0 |
| Thursday | 0 |
| Thursday Night | 0 |
| Thursday | 0 |
| Snoqualmie Pass | Precipitation Forecast |
|---|---|
| Sunday Night | 0 |
| Thursday | 0 |
| Thursday Night | 0 |
| Thursday | 0 |
| Leavenworth | Precipitation Forecast |
|---|---|
| Sunday Night | 0 |
| Thursday | 0 |
| Thursday Night | 0 |
| Thursday | 0 |
| Mission Ridge | Precipitation Forecast |
|---|---|
| Sunday Night | 0 |
| Thursday | 0 |
| Thursday Night | 0 |
| Thursday | 0 |
| Crystal Mt | Precipitation Forecast |
|---|---|
| Sunday Night | LT 0.10 |
| Thursday | 0 |
| Thursday Night | 0 |
| Thursday | 0 |
| Paradise | Precipitation Forecast |
|---|---|
| Sunday Night | 0 |
| Thursday | 0 |
| Thursday Night | 0 |
| Thursday | 0 |
| White Pass | Precipitation Forecast |
|---|---|
| Sunday Night | 0 |
| Thursday | 0 |
| Thursday Night | 0 |
| Thursday | 0 |
| Mt Hood Meadows | Precipitation Forecast |
|---|---|
| Sunday Night | LT 0.10 |
| Thursday | 0 |
| Thursday Night | 0 |
| Thursday | 0 |
| Timberline | Precipitation Forecast |
|---|---|
| Sunday Night | LT 0.10 |
| Thursday | 0 |
| Thursday Night | 0 |
| Thursday | 0 |
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 Sunday, December 2, 2018
Free Winds at 5000' (mph)
| Hurricane Ridge | Mt. Baker | Stevens to Snoqualmie Pass | Mt. Rainier | Mt. Hood | |
|---|---|---|---|---|---|
| Sunday Evening | E 0 - 10 | NE 0 - 10 | VAR 0 - 10 | VAR 0 - 10 | S 0 - 10 |
| Sunday Night | E 0 - 10 | ENE 0 - 10 | VAR 0 - 10 | SE 0 - 10 | SE 5 - 15 |
| Monday Morning | ENE 5 - 15 | ENE 5 - 15 | ESE 5 - 15 | ESE 5 - 15 | ESE 5 - 15 |
| Monday Afternoon | E 5 - 15 | ENE 5 - 15 | E 5 - 15 | E 5 - 15 | ESE 10 - 20 |
| Hurricane Ridge | Elevation |
|---|---|
| Sunday Evening | E 0 - 10 |
| Sunday Night | E 0 - 10 |
| Monday Morning | ENE 5 - 15 |
| Monday Afternoon | E 5 - 15 |
| Mt. Baker | Elevation |
|---|---|
| Sunday Evening | NE 0 - 10 |
| Sunday Night | ENE 0 - 10 |
| Monday Morning | ENE 5 - 15 |
| Monday Afternoon | ENE 5 - 15 |
| Stevens and Snoqualmie Pass | Elevation |
|---|---|
| Sunday Evening | VAR 0 - 10 |
| Sunday Night | VAR 0 - 10 |
| Monday Morning | ESE 5 - 15 |
| Monday Afternoon | E 5 - 15 |
| Mt. Rainier | Elevation |
|---|---|
| Sunday Evening | VAR 0 - 10 |
| Sunday Night | SE 0 - 10 |
| Monday Morning | ESE 5 - 15 |
| Monday Afternoon | E 5 - 15 |
| Mt. Hood | Elevation |
|---|---|
| Sunday Evening | S 0 - 10 |
| Sunday Night | SE 5 - 15 |
| Monday Morning | ESE 5 - 15 |
| Monday Afternoon | ESE 10 - 20 |
| Hurricane Ridge | Direction - Speed |
|---|---|
| Sunday Evening | E 0 - 10 |
| Sunday Night | E 0 - 10 |
| Monday Morning | ENE 5 - 15 |
| Monday Afternoon | E 5 - 15 |
| Mt. Baker | Direction - Speed |
|---|---|
| Sunday Evening | NE 0 - 10 |
| Sunday Night | ENE 0 - 10 |
| Monday Morning | ENE 5 - 15 |
| Monday Afternoon | ENE 5 - 15 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Sunday Evening | VAR 0 - 10 |
| Sunday Night | VAR 0 - 10 |
| Monday Morning | ESE 5 - 15 |
| Monday Afternoon | E 5 - 15 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Sunday Evening | VAR 0 - 10 |
| Sunday Night | SE 0 - 10 |
| Monday Morning | ESE 5 - 15 |
| Monday Afternoon | E 5 - 15 |
| Mt. Hood | Direction - Speed |
|---|---|
| Sunday Evening | S 0 - 10 |
| Sunday Night | SE 5 - 15 |
| Monday Morning | ESE 5 - 15 |
| Monday Afternoon | ESE 10 - 20 |
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 | |
|---|---|---|---|---|---|
| Sunday Evening | NW 5 - 15 | NNW 5 - 15 | NNW 5 - 15 | NW 0 - 10 | W 0 - 10 |
| Sunday Night | WNW 0 - 10 | NW 5 - 15 | NW 5 - 15 | W 0 - 10 | W 0 - 10 |
| Monday Morning | NNW 5 - 15 | NW 5 - 15 | NW 5 - 15 | NNW 5 - 15 | VAR 0 - 10 |
| Monday Afternoon | NE 0 - 10 | NNW 0 - 10 | WNW 5 - 15 | VAR 0 - 10 | S 0 - 10 |
| Mt. Baker | Direction - Speed |
|---|---|
| Sunday Evening | NW 5 - 15 |
| Sunday Night | WNW 0 - 10 |
| Monday Morning | NNW 5 - 15 |
| Monday Afternoon | NE 0 - 10 |
| Washington Pass | Direction - Speed |
|---|---|
| Sunday Evening | NNW 5 - 15 |
| Sunday Night | NW 5 - 15 |
| Monday Morning | NW 5 - 15 |
| Monday Afternoon | NNW 0 - 10 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Sunday Evening | NNW 5 - 15 |
| Sunday Night | NW 5 - 15 |
| Monday Morning | NW 5 - 15 |
| Monday Afternoon | WNW 5 - 15 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Sunday Evening | NW 0 - 10 |
| Sunday Night | W 0 - 10 |
| Monday Morning | NNW 5 - 15 |
| Monday Afternoon | VAR 0 - 10 |
| Mt. Hood | Direction - Speed |
|---|---|
| Sunday Evening | W 0 - 10 |
| Sunday Night | W 0 - 10 |
| Monday Morning | VAR 0 - 10 |
| Monday Afternoon | S 0 - 10 |
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 Sunday, December 2, 2018
Extended Weather Synopsis for Thursday night through Thursday
Tuesday night through Thursday we are locked in quiescent pattern with fair weather under a SW-NE tilted high pressure edging into our region with a low pressure spinning to our south over California and the northern branch of the jetstream far to the north.
The weather pattern will continue to increase the pressure difference across the Cascades, increasing the moderate easterly flow during this time period.
Expect sunny days and cold, clear nights with warmer weather west of the Cascade crest and colder inversion conditions with low elevation fog east of the Cascade crest.
Extended Snow/Freezing Levels
| Mt. Baker | Snoqualmie Pass | Mt. Hood | Easterly Flow * | ||
|---|---|---|---|---|---|
| Tuesday Night | Freezing Level | 4000' - 5000' | 3000' - 4000' | 5000' - 6000' | * |
| Wednesday | Freezing Level | 4000' - 5000' | 3000' - 4000' | 2000' - 4000' | * |
| Wednesday Night | Freezing Level | 4000' - 5000' | 3000' - 4000' | 2000' - 4000' | * |
| Thursday | Freezing Level | 4500' - 5500' | 3000' - 4000' | 5000' - 7000' | * |
| Mt. Baker | Elevation |
|---|---|
| Tuesday Night |
Freezing Level 4000' - 5000' (Easterly Flow *) |
| Wednesday |
Freezing Level 4000' - 5000' (Easterly Flow *) |
| Wednesday Night |
Freezing Level 4000' - 5000' (Easterly Flow *) |
| Thursday |
Freezing Level 4500' - 5500' (Easterly Flow *) |
| Snoqualmie Pass | Elevation |
|---|---|
| Tuesday Night |
Freezing Level 3000' - 4000' (Easterly Flow *) |
| Wednesday |
Freezing Level 3000' - 4000' (Easterly Flow *) |
| Wednesday Night |
Freezing Level 3000' - 4000' (Easterly Flow *) |
| Thursday |
Freezing Level 3000' - 4000' (Easterly Flow *) |
| Mt. Hood | Elevation |
|---|---|
| Tuesday Night |
Freezing Level 5000' - 6000' (Easterly Flow *) |
| Wednesday |
Freezing Level 2000' - 4000' (Easterly Flow *) |
| Wednesday Night |
Freezing Level 2000' - 4000' (Easterly Flow *) |
| Thursday |
Freezing Level 5000' - 7000' (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.
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 1, 2018
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