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 night through Thursday
The split flow pattern in place since Monday will continue Thursday night and Friday with a ridge of high pressure pushing from the Pacific Northwest northward into British Columbia while a slow-moving low pressure gradually shifts eastward across southern California. The lack of atmospheric forcing leads to clear skies west of the Cascade Crest with gradual warming aloft; meanwhile, to the east, the light to moderate easterly low-level flow keeps a deep layer of cold air banked against the mountains, producing low elevation clouds and freezing fog in place.
A weak front will move into the near-shore waters by Friday afternoon but is unlikely to decrease cloud cover significantly on Friday. It will bring an end to the split flow pattern late Friday night along with a band of generally light rain and snow as it passes. The approaching front will bring warmer air to accompany the S-SW flow aloft, producing rain at lower elevation locations west of the Cascade Crest, but most Cascade passes and locations east will remain snow through Saturday as the weak front fizzles and exits leaving a shortwave ridge ahead of a second slightly stronger front offshore.
Weather Forecast
Hurricane Ridge
| Thursday Night | Mostly clear, light winds with areas of low clouds or fog in the lower elevations and valleys. |
| Friday | Mostly sunny with mild daytime temperatures. |
Mt. Baker
| Thursday Night | Mostly clear with light winds. |
| Friday | Mostly sunny and mild. Light winds. |
Stevens and Snoqualmie Pass
| Thursday Night | Mostly clear and cold. Areas of low clouds or fog lower elevations and eastern approaches to the passes. Moderate and gusty easterly winds. |
| Friday | Becoming mostly sunny except for areas of low clouds or fog, lower elevations, and valleys. Light to moderate easterly winds. |
Mt. Rainier and Crystal
| Thursday Night | Mostly clear with light to moderate easterly winds. |
| Friday | Mostly sunny and mild. Light to moderate easterly winds. |
Washington Pass and Leavenworth
| Thursday Night | Cold. Areas of low clouds or fog lower elevations and valleys, otherwise, mostly clear mid and upper elevations. |
| Friday | Mostly sunny. Continued cold lower elevations with warming upper elevations. Patchy low clouds or fog lower elevations and valleys. |
Mt. Hood
| Thursday Night | Mostly clear with light winds. Warm aloft with inversion and low clouds. |
| Friday | Mostly clear with light winds. Warm aloft with inversion and low clouds. |
Issued: 4:14 PM PST Thursday, December 6, 2018
Snow/Freezing Level (ft)
| Hurricane Ridge | Mt. Baker | Washington Pass | Leavenworth | Stevens Pass | Snoqualmie Pass | Mt. Rainier, Crystal & White Pass | Mt. Hood | ||
|---|---|---|---|---|---|---|---|---|---|
| Thursday Evening | Freezing Level * | 5500' | 3000' | 1500' | 500' | 500' | 1500' | 2000' | 6000' |
| Thursday Night | Freezing Level * | 6000' | 3000' | 1500' | 500' | 500' | 2000' | 2500' | 6000' |
| Friday Morning | Freezing Level * | 6000' | 3500' | 1500' | 500' | 1000' | 2500' | 3000' | 6000' |
| Friday Afternoon | Freezing Level * | 5500' | 4500' | 2500' | 2000' | 2500' | 3500' | 4000' | 6000' |
| Friday Evening | Snow Level * | 4500' | 3500' | 1500' | 1000' | 1500' | 2500' | 3000' | 4500' |
| Friday Night | Snow Level * | 4500' | 3500' | 2000' | 1000' | 2000' | 2500' | 3500' | 4500' |
| Saturday Morning | Snow Level * | 4500' | 3500' | 2000' | 3500' | 2000' | 3000' | 3500' | 4500' |
| Saturday Afternoon | Snow Level * | 5000' | 3500' | 2500' | 2000' | 2500' | 3500' | 5000' | 6500' |
| Hurricane Ridge | Elevation |
|---|---|
| Thursday Evening |
Freezing Level 5500' (Easterly Flow *) |
| Thursday Night |
Freezing Level 6000' (Easterly Flow *) |
| Friday Morning |
Freezing Level 6000' (Easterly Flow *) |
| Friday Afternoon |
Freezing Level 5500' (Easterly Flow *) |
| Friday Evening |
Snow Level 4500' (Easterly Flow *) |
| Friday Night |
Snow Level 4500' (Easterly Flow *) |
| Saturday Morning |
Snow Level 4500' (Easterly Flow *) |
| Saturday Afternoon |
Snow Level 5000' (Easterly Flow *) |
| Mt. Baker | Elevation |
|---|---|
| Thursday Evening |
Freezing Level 3000' (Easterly Flow *) |
| Thursday Night |
Freezing Level 3000' (Easterly Flow *) |
| Friday Morning |
Freezing Level 3500' (Easterly Flow *) |
| Friday Afternoon |
Freezing Level 4500' (Easterly Flow *) |
| Friday Evening |
Snow Level 3500' (Easterly Flow *) |
| Friday Night |
Snow Level 3500' (Easterly Flow *) |
| Saturday Morning |
Snow Level 3500' (Easterly Flow *) |
| Saturday Afternoon |
Snow Level 3500' (Easterly Flow *) |
| Washington Pass | Elevation |
|---|---|
| Thursday Evening |
Freezing Level 1500' (Easterly Flow *) |
| Thursday Night |
Freezing Level 1500' (Easterly Flow *) |
| Friday Morning |
Freezing Level 1500' (Easterly Flow *) |
| Friday Afternoon |
Freezing Level 2500' (Easterly Flow *) |
| Friday Evening |
Snow Level 1500' (Easterly Flow *) |
| Friday Night |
Snow Level 2000' (Easterly Flow *) |
| Saturday Morning |
Snow Level 2000' (Easterly Flow *) |
| Saturday Afternoon |
Snow Level 2500' (Easterly Flow *) |
| Leavenworth | Elevation |
|---|---|
| Thursday Evening |
Freezing Level 500' (Easterly Flow *) |
| Thursday Night |
Freezing Level 500' (Easterly Flow *) |
| Friday Morning |
Freezing Level 500' (Easterly Flow *) |
| Friday Afternoon |
Freezing Level 2000' (Easterly Flow *) |
| Friday Evening |
Snow Level 1000' (Easterly Flow *) |
| Friday Night |
Snow Level 1000' (Easterly Flow *) |
| Saturday Morning |
Snow Level 3500' (Easterly Flow *) |
| Saturday Afternoon |
Snow Level 2000' (Easterly Flow *) |
| Stevens Pass | Elevation |
|---|---|
| Thursday Evening |
Freezing Level 500' (Easterly Flow *) |
| Thursday Night |
Freezing Level 500' (Easterly Flow *) |
| Friday Morning |
Freezing Level 1000' (Easterly Flow *) |
| Friday Afternoon |
Freezing Level 2500' (Easterly Flow *) |
| Friday Evening |
Snow Level 1500' (Easterly Flow *) |
| Friday Night |
Snow Level 2000' (Easterly Flow *) |
| Saturday Morning |
Snow Level 2000' (Easterly Flow *) |
| Saturday Afternoon |
Snow Level 2500' (Easterly Flow *) |
| Snoqualmie Pass | Elevation |
|---|---|
| Thursday Evening |
Freezing Level 1500' (Easterly Flow *) |
| Thursday Night |
Freezing Level 2000' (Easterly Flow *) |
| Friday Morning |
Freezing Level 2500' (Easterly Flow *) |
| Friday Afternoon |
Freezing Level 3500' (Easterly Flow *) |
| Friday Evening |
Snow Level 2500' (Easterly Flow *) |
| Friday Night |
Snow Level 2500' (Easterly Flow *) |
| Saturday Morning |
Snow Level 3000' (Easterly Flow *) |
| Saturday Afternoon |
Snow Level 3500' (Easterly Flow *) |
| Mt. Rainier & Crystal | Elevation |
|---|---|
| Thursday Evening |
Freezing Level 2000' (Easterly Flow *) |
| Thursday Night |
Freezing Level 2500' (Easterly Flow *) |
| Friday Morning |
Freezing Level 3000' (Easterly Flow *) |
| Friday Afternoon |
Freezing Level 4000' (Easterly Flow *) |
| Friday Evening |
Snow Level 3000' (Easterly Flow *) |
| Friday Night |
Snow Level 3500' (Easterly Flow *) |
| Saturday Morning |
Snow Level 3500' (Easterly Flow *) |
| Saturday Afternoon |
Snow Level 5000' (Easterly Flow *) |
| Mt. Hood | Elevation |
|---|---|
| Thursday Evening |
Freezing Level 6000' (Easterly Flow *) |
| Thursday Night |
Freezing Level 6000' (Easterly Flow *) |
| Friday Morning |
Freezing Level 6000' (Easterly Flow *) |
| Friday Afternoon |
Freezing Level 6000' (Easterly Flow *) |
| Friday Evening |
Snow Level 4500' (Easterly Flow *) |
| Friday Night |
Snow Level 4500' (Easterly Flow *) |
| Saturday Morning |
Snow Level 4500' (Easterly Flow *) |
| Saturday Afternoon |
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
| Thursday 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 | LT 0.10 | 0 |
| Mt Baker Ski Area | 0 | 0 | LT 0.10 | LT 0.25 |
| Washington Pass | 0 | 0 | 0 | LT 0.10 |
| Stevens Pass | 0 | 0 | 0 | LT 0.10 |
| Snoqualmie Pass | 0 | 0 | LT 0.10 | LT 0.10 |
| Leavenworth | 0 | 0 | 0 | 0 |
| Mission Ridge | 0 | 0 | 0 | 0 |
| Crystal Mt | 0 | 0 | LT 0.10 | LT 0.10 |
| Paradise | 0 | 0 | LT 0.25 | LT 0.25 |
| White Pass | 0 | 0 | LT 0.10 | LT 0.10 |
| Mt Hood Meadows | 0 | 0 | 0.25 | LT 0.10 |
| Timberline | 0 | 0 | 0.25 | LT 0.10 |
| Hurricane Ridge | Precipitation Forecast |
|---|---|
| Thursday Night | 0 |
| Thursday | 0 |
| Thursday Night | LT 0.10 |
| Thursday | 0 |
| Mt Baker Ski Area | Precipitation Forecast |
|---|---|
| Thursday Night | 0 |
| Thursday | 0 |
| Thursday Night | LT 0.10 |
| Thursday | LT 0.25 |
| Washington Pass | Precipitation Forecast |
|---|---|
| Thursday Night | 0 |
| Thursday | 0 |
| Thursday Night | 0 |
| Thursday | LT 0.10 |
| Stevens Pass | Precipitation Forecast |
|---|---|
| Thursday Night | 0 |
| Thursday | 0 |
| Thursday Night | 0 |
| Thursday | LT 0.10 |
| Snoqualmie Pass | Precipitation Forecast |
|---|---|
| Thursday Night | 0 |
| Thursday | 0 |
| Thursday Night | LT 0.10 |
| Thursday | LT 0.10 |
| Leavenworth | Precipitation Forecast |
|---|---|
| Thursday Night | 0 |
| Thursday | 0 |
| Thursday Night | 0 |
| Thursday | 0 |
| Mission Ridge | Precipitation Forecast |
|---|---|
| Thursday Night | 0 |
| Thursday | 0 |
| Thursday Night | 0 |
| Thursday | 0 |
| Crystal Mt | Precipitation Forecast |
|---|---|
| Thursday Night | 0 |
| Thursday | 0 |
| Thursday Night | LT 0.10 |
| Thursday | LT 0.10 |
| Paradise | Precipitation Forecast |
|---|---|
| Thursday Night | 0 |
| Thursday | 0 |
| Thursday Night | LT 0.25 |
| Thursday | LT 0.25 |
| White Pass | Precipitation Forecast |
|---|---|
| Thursday Night | 0 |
| Thursday | 0 |
| Thursday Night | LT 0.10 |
| Thursday | LT 0.10 |
| Mt Hood Meadows | Precipitation Forecast |
|---|---|
| Thursday Night | 0 |
| Thursday | 0 |
| Thursday Night | 0.25 |
| Thursday | LT 0.10 |
| Timberline | Precipitation Forecast |
|---|---|
| Thursday Night | 0 |
| Thursday | 0 |
| Thursday Night | 0.25 |
| Thursday | LT 0.10 |
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: 4:14 PM PST Thursday, December 6, 2018
Free Winds at 5000' (mph)
| Hurricane Ridge | Mt. Baker | Stevens to Snoqualmie Pass | Mt. Rainier | Mt. Hood | |
|---|---|---|---|---|---|
| Thursday Evening | SE 0 - 10 | E 0 - 10 | E 10 - 20 | E 5 - 15 | E 10 - 20 |
| Thursday Night | SE 5 - 15 | E 0 - 10 | E 10 - 20 | ESE 5 - 15 | ESE 5 - 15 |
| Friday Morning | SSE 10 - 20 | SE 5 - 15 | SE 10 - 20 | ESE 5 - 15 | ESE 5 - 15 |
| Friday Afternoon | SSE 15 - 25 | SSE 10 - 20 | ESE 10 - 20 | ESE 10 - 20 | SSE 10 - 20 |
| Hurricane Ridge | Elevation |
|---|---|
| Thursday Evening | SE 0 - 10 |
| Thursday Night | SE 5 - 15 |
| Friday Morning | SSE 10 - 20 |
| Friday Afternoon | SSE 15 - 25 |
| Mt. Baker | Elevation |
|---|---|
| Thursday Evening | E 0 - 10 |
| Thursday Night | E 0 - 10 |
| Friday Morning | SE 5 - 15 |
| Friday Afternoon | SSE 10 - 20 |
| Stevens and Snoqualmie Pass | Elevation |
|---|---|
| Thursday Evening | E 10 - 20 |
| Thursday Night | E 10 - 20 |
| Friday Morning | SE 10 - 20 |
| Friday Afternoon | ESE 10 - 20 |
| Mt. Rainier | Elevation |
|---|---|
| Thursday Evening | E 5 - 15 |
| Thursday Night | ESE 5 - 15 |
| Friday Morning | ESE 5 - 15 |
| Friday Afternoon | ESE 10 - 20 |
| Mt. Hood | Elevation |
|---|---|
| Thursday Evening | E 10 - 20 |
| Thursday Night | ESE 5 - 15 |
| Friday Morning | ESE 5 - 15 |
| Friday Afternoon | SSE 10 - 20 |
| Hurricane Ridge | Direction - Speed |
|---|---|
| Thursday Evening | SE 0 - 10 |
| Thursday Night | SE 5 - 15 |
| Friday Morning | SSE 10 - 20 |
| Friday Afternoon | SSE 15 - 25 |
| Mt. Baker | Direction - Speed |
|---|---|
| Thursday Evening | E 0 - 10 |
| Thursday Night | E 0 - 10 |
| Friday Morning | SE 5 - 15 |
| Friday Afternoon | SSE 10 - 20 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Thursday Evening | E 10 - 20 |
| Thursday Night | E 10 - 20 |
| Friday Morning | SE 10 - 20 |
| Friday Afternoon | ESE 10 - 20 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Thursday Evening | E 5 - 15 |
| Thursday Night | ESE 5 - 15 |
| Friday Morning | ESE 5 - 15 |
| Friday Afternoon | ESE 10 - 20 |
| Mt. Hood | Direction - Speed |
|---|---|
| Thursday Evening | E 10 - 20 |
| Thursday Night | ESE 5 - 15 |
| Friday Morning | ESE 5 - 15 |
| Friday Afternoon | SSE 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 | |
|---|---|---|---|---|---|
| Thursday Evening | S 0 - 10 | VAR 0 - 10 | W 0 - 10 | W 0 - 10 | W 5 - 15 |
| Thursday Night | SW 5 - 15 | SW 5 - 15 | WSW 5 - 15 | WSW 5 - 15 | WSW 10 - 20 |
| Friday Morning | SSW 5 - 15 | WSW 5 - 15 | WSW 10 - 20 | W 10 - 20 | WSW 10 - 20 |
| Friday Afternoon | SSW 15 - 25 | WSW 10 - 20 | WSW 15 - 25 | WSW 15 - 25 | WSW 15 - 25 |
| Mt. Baker | Direction - Speed |
|---|---|
| Thursday Evening | S 0 - 10 |
| Thursday Night | SW 5 - 15 |
| Friday Morning | SSW 5 - 15 |
| Friday Afternoon | SSW 15 - 25 |
| Washington Pass | Direction - Speed |
|---|---|
| Thursday Evening | VAR 0 - 10 |
| Thursday Night | SW 5 - 15 |
| Friday Morning | WSW 5 - 15 |
| Friday Afternoon | WSW 10 - 20 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Thursday Evening | W 0 - 10 |
| Thursday Night | WSW 5 - 15 |
| Friday Morning | WSW 10 - 20 |
| Friday Afternoon | WSW 15 - 25 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Thursday Evening | W 0 - 10 |
| Thursday Night | WSW 5 - 15 |
| Friday Morning | W 10 - 20 |
| Friday Afternoon | WSW 15 - 25 |
| Mt. Hood | Direction - Speed |
|---|---|
| Thursday Evening | W 5 - 15 |
| Thursday Night | WSW 10 - 20 |
| Friday Morning | WSW 10 - 20 |
| Friday Afternoon | WSW 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.
Issued: 4:14 PM PST Thursday, December 6, 2018
Extended Weather Synopsis for Thursday night through Thursday
Saturday night the shortwave ridge will break down as a frontal system approaches and then arrives on Sunday bringing light to moderate precipitation to the region with Mt. Baker and the windward slopes of the Olympic Mountains favored by the S-SW flow. The warmer air in place west of the Cascade Crest will gradually be replaced by a cooler air mass and showery conditions Sunday night with a cool, weakly unstable trough over the region on Monday.
Monday night will feature a break between storm systems as a stronger frontal system arrives on a Northwest flow Tuesday afternoon with initially elevated snow levels lowering rapidly.
Extended Snow/Freezing Levels
| Mt. Baker | Snoqualmie Pass | Mt. Hood | Easterly Flow * | ||
|---|---|---|---|---|---|
| Saturday Night | Snow Level | 4500' - 5500' | 3000' - 4000' | 6500' - 7500' | * |
| Sunday | Snow Level | 4000' - 5000' | 3000' - 4000' | 4000' - 6000' | * |
| Sunday Night | Snow Level | 2500' - 3500' | 3000' - 4000' | 3500' - 4500' | |
| Monday | Snow Level | 2500' - 3500' | 2500' - 3500' | 3000' - 4000' |
| Mt. Baker | Elevation |
|---|---|
| Saturday Night |
Snow Level 4500' - 5500' (Easterly Flow *) |
| Sunday |
Snow Level 4000' - 5000' (Easterly Flow *) |
| Sunday Night |
Snow Level 2500' - 3500' |
| Monday |
Snow Level 2500' - 3500' |
| Snoqualmie Pass | Elevation |
|---|---|
| Saturday Night |
Snow Level 3000' - 4000' (Easterly Flow *) |
| Sunday |
Snow Level 3000' - 4000' (Easterly Flow *) |
| Sunday Night |
Snow Level 3000' - 4000' |
| Monday |
Snow Level 2500' - 3500' |
| Mt. Hood | Elevation |
|---|---|
| Saturday Night |
Snow Level 6500' - 7500' (Easterly Flow *) |
| Sunday |
Snow Level 4000' - 6000' (Easterly Flow *) |
| Sunday Night |
Snow Level 3500' - 4500' |
| Monday |
Snow Level 3000' - 4000' |
* 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 2, 2018
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