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 Saturday
The Pacific Northwest sits between a deep trough over the western portion of the U.S. and a broad, flat ridge offshore. A significant moisture-laden warm frontal system is spilling over the top of the flat ridge. By late Thursday night, light snow will develop in the Olympic mountains. The Cascades will remain mostly clear and cold with high clouds arriving late.
On Friday, the warm front will be draped parallel to the British Colombia and Washington coastlines. Clouds will lower and thicken with light snow arriving in the Olympics in the morning and in the Cascades by early afternoon.
Friday night the warm front crosses the region bringing moderate to heavy snow to Western Washington and a changeover to rain as the snow line rises to near Cascade Crest level. Easterly winds through the passes friday evening will keep the passes cold until the frontal passage and associated wind shift around 10 PM. The warm sector of the storm will remain over the forecast area on Saturday. Winds will increase to moderate or strong during the day Saturday as moderate rain continues in most locations with snow levels staying above 4500 ft until the cold frontal passage on Saturday evening.
On Friday night and Saturday, Mt. Hood will experience significantly lighter rain and snow as the energy and moisture stay north.
Weather Forecast
Hurricane Ridge
| Thursday Night | Increasing light snow. Light winds. |
| Friday | Further increasing light snow. Light wind. |
Mt. Baker
| Thursday Night | Increasing high clouds lowering and thickening. Fog possible in the valleys. Variable wind. |
| Friday | Increasing light snow. Increasing light wind. |
Washington Pass and Leavenworth
| Thursday Night | High cloud cover. Light or variable wind. Fog possibly developing in the valleys. |
| Friday | Light snow developing from late morning onward and increasing. Light wind. |
Stevens and Snoqualmie Pass
| Thursday Night | Increasing high clouds lowering and thickening. Light wind. |
| Friday | Light snow increasing and becoming moderate by the end of the day. Gradual warming trend. Light wind increasing in the afternoon. |
Mt. Rainier, Crystal and White Pass
| Thursday Night | Increasing high clouds lowering and thickening. Light wind. |
| Friday | Light snow increasing and becoming moderate by the end of the day. Gradual warming trend. Light wind increasing in the afternoon. |
Mt. Hood
| Thursday Night | High clouds lowering and thickening. Light to moderate wind. |
| Friday | Light snow. Light to moderate wind. |
Issued: 2:31 PM PST Thursday, December 27, 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 | 3000' | 1500' | 1500' | 1500' | 1500' | 2000' | 2000' | 2500' |
| Thursday Night | Snow Level | 2500' | 500' | 0' | 500' | 500' | 500' | 500' | 1000' |
| Friday Morning | Snow Level | 3000' | 500' | 0' | 500' | 500' | 1000' | 1500' | 1500' |
| Friday Afternoon | Snow Level | 4000' | 1500' | 1500' | 1500' | 2500' | 2500' | 3000' | 2500' |
| Friday Evening | Snow Level * | 6500' | 2500' | 2500' | 1500' | 3000' | 3500' | 3500' | 3500' |
| Friday Night | Snow Level | 7000' | 4500' | 3000' | 3000' | 4500' | 5500' | 5000' | 5500' |
| Saturday Morning | Snow Level | 6500' | 5500' | 4500' | 5500' | 5500' | 6000' | 6500' | 6500' |
| Saturday Afternoon | Snow Level | 6000' | 5500' | 5000' | 5500' | 5000' | 5500' | 5500' | 6000' |
| Hurricane Ridge | Elevation |
|---|---|
| Thursday Evening |
Freezing Level 3000' |
| Thursday Night |
Snow Level 2500' |
| Friday Morning |
Snow Level 3000' |
| Friday Afternoon |
Snow Level 4000' |
| Friday Evening |
Snow Level 6500' (Easterly Flow *) |
| Friday Night |
Snow Level 7000' |
| Saturday Morning |
Snow Level 6500' |
| Saturday Afternoon |
Snow Level 6000' |
| Mt. Baker | Elevation |
|---|---|
| Thursday Evening |
Freezing Level 1500' |
| Thursday Night |
Snow Level 500' |
| Friday Morning |
Snow Level 500' |
| Friday Afternoon |
Snow Level 1500' |
| Friday Evening |
Snow Level 2500' (Easterly Flow *) |
| Friday Night |
Snow Level 4500' |
| Saturday Morning |
Snow Level 5500' |
| Saturday Afternoon |
Snow Level 5500' |
| Washington Pass | Elevation |
|---|---|
| Thursday Evening |
Freezing Level 1500' |
| Thursday Night |
Snow Level 0' |
| Friday Morning |
Snow Level 0' |
| Friday Afternoon |
Snow Level 1500' |
| Friday Evening |
Snow Level 2500' (Easterly Flow *) |
| Friday Night |
Snow Level 3000' |
| Saturday Morning |
Snow Level 4500' |
| Saturday Afternoon |
Snow Level 5000' |
| Leavenworth | Elevation |
|---|---|
| Thursday Evening |
Freezing Level 1500' |
| Thursday Night |
Snow Level 500' |
| Friday Morning |
Snow Level 500' |
| Friday Afternoon |
Snow Level 1500' |
| Friday Evening |
Snow Level 1500' (Easterly Flow *) |
| Friday Night |
Snow Level 3000' |
| Saturday Morning |
Snow Level 5500' |
| Saturday Afternoon |
Snow Level 5500' |
| Stevens Pass | Elevation |
|---|---|
| Thursday Evening |
Freezing Level 1500' |
| Thursday Night |
Snow Level 500' |
| Friday Morning |
Snow Level 500' |
| Friday Afternoon |
Snow Level 2500' |
| Friday Evening |
Snow Level 3000' (Easterly Flow *) |
| Friday Night |
Snow Level 4500' |
| Saturday Morning |
Snow Level 5500' |
| Saturday Afternoon |
Snow Level 5000' |
| Snoqualmie Pass | Elevation |
|---|---|
| Thursday Evening |
Freezing Level 2000' |
| Thursday Night |
Snow Level 500' |
| Friday Morning |
Snow Level 1000' |
| Friday Afternoon |
Snow Level 2500' |
| Friday Evening |
Snow Level 3500' (Easterly Flow *) |
| Friday Night |
Snow Level 5500' |
| Saturday Morning |
Snow Level 6000' |
| Saturday Afternoon |
Snow Level 5500' |
| Mt. Rainier & Crystal | Elevation |
|---|---|
| Thursday Evening |
Freezing Level 2000' |
| Thursday Night |
Snow Level 500' |
| Friday Morning |
Snow Level 1500' |
| Friday Afternoon |
Snow Level 3000' |
| Friday Evening |
Snow Level 3500' (Easterly Flow *) |
| Friday Night |
Snow Level 5000' |
| Saturday Morning |
Snow Level 6500' |
| Saturday Afternoon |
Snow Level 5500' |
| Mt. Hood | Elevation |
|---|---|
| Thursday Evening |
Freezing Level 2500' |
| Thursday Night |
Snow Level 1000' |
| Friday Morning |
Snow Level 1500' |
| Friday Afternoon |
Snow Level 2500' |
| Friday Evening |
Snow Level 3500' (Easterly Flow *) |
| Friday Night |
Snow Level 5500' |
| Saturday Morning |
Snow Level 6500' |
| Saturday Afternoon |
Snow Level 6000' |
* 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 | Saturday | Saturday Night | Saturday | |
|---|---|---|---|---|
| 4 pm - 4 am | 4 am - 4 pm | 4 pm - 4 am | 4 am - 4 pm | |
| Hurricane Ridge | LT 0.10 | 0.25 | 0.25 | 0.50 - 0.75 |
| Mt Baker Ski Area | 0 | 0.25 | 0.75 | 1.00 |
| Washington Pass | 0 | LT 0.10 | 0.25 | 0.25 - 0.50 |
| Leavenworth | 0 | LT 0.10 | LT 0.25 | LT 0.25 |
| Stevens Pass | 0 | LT 0.25 | 0.75 | 0.50 - 0.75 |
| Snoqualmie Pass | 0 | 0.25 | 1.00 - 1.50 | 0.75 |
| Mission Ridge | 0 | LT 0.10 | LT 0.10 | 0.25 |
| Crystal Mt | 0 | LT 0.25 | 0.25 | 0.25 |
| Paradise | 0 | 0.25 | 1.50 | 0.75 |
| White Pass | 0 | LT 0.10 | 0.25 | 0.25 |
| Mt Hood Meadows | 0 | LT 0.10 | 0.25 - 0.50 | LT 0.25 |
| Timberline | 0 | LT 0.10 | 0.25 - 0.50 | 0.25 |
| Hurricane Ridge | Precipitation Forecast |
|---|---|
| Thursday Night | LT 0.10 |
| Saturday | 0.25 |
| Saturday Night | 0.25 |
| Saturday | 0.50 - 0.75 |
| Mt Baker Ski Area | Precipitation Forecast |
|---|---|
| Thursday Night | 0 |
| Saturday | 0.25 |
| Saturday Night | 0.75 |
| Saturday | 1.00 |
| Washington Pass | Precipitation Forecast |
|---|---|
| Thursday Night | 0 |
| Saturday | LT 0.10 |
| Saturday Night | 0.25 |
| Saturday | 0.25 - 0.50 |
| Leavenworth | Precipitation Forecast |
|---|---|
| Thursday Night | 0 |
| Saturday | LT 0.10 |
| Saturday Night | LT 0.25 |
| Saturday | LT 0.25 |
| Stevens Pass | Precipitation Forecast |
|---|---|
| Thursday Night | 0 |
| Saturday | LT 0.25 |
| Saturday Night | 0.75 |
| Saturday | 0.50 - 0.75 |
| Snoqualmie Pass | Precipitation Forecast |
|---|---|
| Thursday Night | 0 |
| Saturday | 0.25 |
| Saturday Night | 1.00 - 1.50 |
| Saturday | 0.75 |
| Mission Ridge | Precipitation Forecast |
|---|---|
| Thursday Night | 0 |
| Saturday | LT 0.10 |
| Saturday Night | LT 0.10 |
| Saturday | 0.25 |
| Crystal Mt | Precipitation Forecast |
|---|---|
| Thursday Night | 0 |
| Saturday | LT 0.25 |
| Saturday Night | 0.25 |
| Saturday | 0.25 |
| Paradise | Precipitation Forecast |
|---|---|
| Thursday Night | 0 |
| Saturday | 0.25 |
| Saturday Night | 1.50 |
| Saturday | 0.75 |
| White Pass | Precipitation Forecast |
|---|---|
| Thursday Night | 0 |
| Saturday | LT 0.10 |
| Saturday Night | 0.25 |
| Saturday | 0.25 |
| Mt Hood Meadows | Precipitation Forecast |
|---|---|
| Thursday Night | 0 |
| Saturday | LT 0.10 |
| Saturday Night | 0.25 - 0.50 |
| Saturday | LT 0.25 |
| Timberline | Precipitation Forecast |
|---|---|
| Thursday Night | 0 |
| Saturday | LT 0.10 |
| Saturday Night | 0.25 - 0.50 |
| Saturday | 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: 2:31 PM PST Thursday, December 27, 2018
Free Winds at 5000' (mph)
| Hurricane Ridge | Mt. Baker | Stevens to Snoqualmie Pass | Mt. Rainier | Mt. Hood | |
|---|---|---|---|---|---|
| Thursday Evening | W 10 - 20 | VAR 0 - 10 | W 5 - 15 | W 5 - 15 | W 10 - 20 |
| Thursday Night | W 5 - 15 | VAR 0 - 10 | W 5 - 15 | W 5 - 15 | WNW 10 - 20 |
| Friday Morning | SW 5 - 15 | SW 0 - 10 | W 5 - 15 | W 5 - 15 | W 10 - 20 |
| Friday Afternoon | SSW 20 - 30 | SSW 10 - 20 | SW 10 - 20 | WSW 10 - 20 | WSW 10 - 20 |
| Hurricane Ridge | Elevation |
|---|---|
| Thursday Evening | W 10 - 20 |
| Thursday Night | W 5 - 15 |
| Friday Morning | SW 5 - 15 |
| Friday Afternoon | SSW 20 - 30 |
| Mt. Baker | Elevation |
|---|---|
| Thursday Evening | VAR 0 - 10 |
| Thursday Night | VAR 0 - 10 |
| Friday Morning | SW 0 - 10 |
| Friday Afternoon | SSW 10 - 20 |
| Stevens and Snoqualmie Pass | Elevation |
|---|---|
| Thursday Evening | W 5 - 15 |
| Thursday Night | W 5 - 15 |
| Friday Morning | W 5 - 15 |
| Friday Afternoon | SW 10 - 20 |
| Mt. Rainier | Elevation |
|---|---|
| Thursday Evening | W 5 - 15 |
| Thursday Night | W 5 - 15 |
| Friday Morning | W 5 - 15 |
| Friday Afternoon | WSW 10 - 20 |
| Mt. Hood | Elevation |
|---|---|
| Thursday Evening | W 10 - 20 |
| Thursday Night | WNW 10 - 20 |
| Friday Morning | W 10 - 20 |
| Friday Afternoon | WSW 10 - 20 |
| Hurricane Ridge | Direction - Speed |
|---|---|
| Thursday Evening | W 10 - 20 |
| Thursday Night | W 5 - 15 |
| Friday Morning | SW 5 - 15 |
| Friday Afternoon | SSW 20 - 30 |
| Mt. Baker | Direction - Speed |
|---|---|
| Thursday Evening | VAR 0 - 10 |
| Thursday Night | VAR 0 - 10 |
| Friday Morning | SW 0 - 10 |
| Friday Afternoon | SSW 10 - 20 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Thursday Evening | W 5 - 15 |
| Thursday Night | W 5 - 15 |
| Friday Morning | W 5 - 15 |
| Friday Afternoon | SW 10 - 20 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Thursday Evening | W 5 - 15 |
| Thursday Night | W 5 - 15 |
| Friday Morning | W 5 - 15 |
| Friday Afternoon | WSW 10 - 20 |
| Mt. Hood | Direction - Speed |
|---|---|
| Thursday Evening | W 10 - 20 |
| Thursday Night | WNW 10 - 20 |
| Friday Morning | W 10 - 20 |
| Friday Afternoon | WSW 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 | NW 10 - 20 | NW 10 - 20 | NNW 25 - 35 | NNW 30 - 45 | NNW 30 - 45 |
| Thursday Night | NW 15 - 25 | NW 15 - 25 | NNW 25 - 35 | NNW 30 - 45 | NNW 30 - 45 |
| Friday Morning | W 15 - 25 | NW 10 - 20 | NW 20 - 30 | NNW 20 - 30 | NNW 20 - 30 |
| Friday Afternoon | W 40 - 60 | WSW 25 - 35 | W 25 - 35 | W 30 - 45 | NW 25 - 35 |
| Mt. Baker | Direction - Speed |
|---|---|
| Thursday Evening | NW 10 - 20 |
| Thursday Night | NW 15 - 25 |
| Friday Morning | W 15 - 25 |
| Friday Afternoon | W 40 - 60 |
| Washington Pass | Direction - Speed |
|---|---|
| Thursday Evening | NW 10 - 20 |
| Thursday Night | NW 15 - 25 |
| Friday Morning | NW 10 - 20 |
| Friday Afternoon | WSW 25 - 35 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Thursday Evening | NNW 25 - 35 |
| Thursday Night | NNW 25 - 35 |
| Friday Morning | NW 20 - 30 |
| Friday Afternoon | W 25 - 35 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Thursday Evening | NNW 30 - 45 |
| Thursday Night | NNW 30 - 45 |
| Friday Morning | NNW 20 - 30 |
| Friday Afternoon | W 30 - 45 |
| Mt. Hood | Direction - Speed |
|---|---|
| Thursday Evening | NNW 30 - 45 |
| Thursday Night | NNW 30 - 45 |
| Friday Morning | NNW 20 - 30 |
| Friday Afternoon | NW 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: 2:31 PM PST Thursday, December 27, 2018
Extended Weather Synopsis for Saturday night through Saturday
A sharp cold front arrives from the NW on Saturday evening bringing a round of heavy rain, high elevation snow, and moderate to strong wind before decreasing winds shift to the NW and temperatures drop rapidly. Decreasing light snow showers will continue behind the front on a N-NW flow through Sunday as cold air continues to flow into the region.
A rebounding ridge offshore once again edges into the region, cutting off the moisture supply Sunday night and bringing clearing skies. High pressure will edge further over the region, bringing warming temperatures to the Olympics and sunny weather across the region.
Extended Snow/Freezing Levels
| Mt. Baker | Snoqualmie Pass | Mt. Hood | Easterly Flow * | ||
|---|---|---|---|---|---|
| Saturday Night | Snow Level | 2000' - 4000' | 2500' - 4500' | 3500' - 5500' | |
| Sunday | Snow Level | 500' - 1500' | 1000' - 2000' | 2000' - 3000' | |
| Sunday Night | Snow Level | 0' - 1000' | 500' - 1500' | 1500' - 2500' | |
| Monday | Snow Level | 0' - 1000' | 500' - 1500' | 1000' - 2000' |
| Mt. Baker | Elevation |
|---|---|
| Saturday Night |
Snow Level 2000' - 4000' |
| Sunday |
Snow Level 500' - 1500' |
| Sunday Night |
Snow Level 0' - 1000' |
| Monday |
Snow Level 0' - 1000' |
| Snoqualmie Pass | Elevation |
|---|---|
| Saturday Night |
Snow Level 2500' - 4500' |
| Sunday |
Snow Level 1000' - 2000' |
| Sunday Night |
Snow Level 500' - 1500' |
| Monday |
Snow Level 500' - 1500' |
| Mt. Hood | Elevation |
|---|---|
| Saturday Night |
Snow Level 3500' - 5500' |
| Sunday |
Snow Level 2000' - 3000' |
| Sunday Night |
Snow Level 1500' - 2500' |
| Monday |
Snow Level 1000' - 2000' |
* 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 27, 2018
The NWAC program is administered by the USDA-Forest Service and operates from the National Weather Service Forecast Office in Seattle. NWAC services are made possible by important collaboration and support from a wide variety of federal, state and private cooperators.