Jump to: Weather Forecast I Snow/Freezing Level I Precipitation I Free Winds 5k I Free Winds 9k I Extended Weather
Weather Synopsis for Friday night through Tuesday
A significant atmospheric river event is well underway in the Pacific Northwest. A cold front is relatively stationary draped from SW Washington across the Puget sound on Friday afternoon. The location of the front should maintain in roughly the same area on Friday night, sucking some very slightly cooler air through the Passes and keeping snow levels slightly lower there. A warm front that passed through most of the region on Thursday night continues to stall near the US-Canadian border, keeping temperatures cooler in the north and we expect this to continue overnight as moisture continues to stream up from the SSW across the region. Adding more significant rain and snow to an already very significant rainfall event.
After midnight Friday night, a deep trough offshore should begin to make eastward progress, gradually starting to cool and dry the region out from the west and that trend will continue through Saturday with the majority of the precipitation shutting off over Washington State during the day with a changeover to snow down to Snoqualmie Pass level, less than 2" likely before it ends. Rain and snow will increase in the Mt. Hood area on Saturday as the precipitation shifts ESE and then tapers over Mt. Hood on Saturday night, while Washington stays mostly cloudy.
On Sunday, the trough sits over the region and some very light precipitation may skirt the Mt. Hood and SE Washington areas. Temperatures will be seasonably cold with snow where it does fall.
Weather Forecast
Hurricane Ridge
| Friday Night | Decreasing moderate rain and snow becoming light after midnight. Snow level dropping. |
| Saturday | Mostly cloudy with a slight chance of snow showers in the morning. |
Mt. Baker
| Friday Night | Heavy rain and snow. |
| Saturday | Light to moderate rain and snow decreasing or ending in the morning hours. Gradually lowering snow levels. |
Washington Pass and Leavenworth
| Friday Night | Heavy snow at Washington Pass. Moderate rain at Leavenworth. A mix of rain and snow in the Methow valley. |
| Saturday | Decreasing light to moderate rain and snow. Gradually lowering snow levels. |
Stevens and Snoqualmie Pass
| Friday Night | Heavy rain and snow. Rain at Snoqualmie and mostly Snow at Stevens Pass. Light to moderate E winds at the Passes, decreasing. |
| Saturday | Decreasing moderate rain and snow. Snow levels dropping to Snoqualmie Pass level sometime during the afternoon. Light W winds through the Passes. |
Mt. Rainier, Crystal and White Pass
| Friday Night | Heavy rain and snow. |
| Saturday | Heavy rain and snow. Gradually lowering snow levels. |
Mt. Hood
| Friday Night | Cloudy and mild with some very light rain or snow. |
| Saturday | Moderate to heavy rain and snow. Rapidly cooling temperatures. |
Issued: 2:43 PM PST Friday, December 20, 2019
Snow/Freezing Level (ft)
| Hurricane Ridge | Mt. Baker | Washington Pass | Leavenworth | Stevens Pass | Snoqualmie Pass | Mt. Rainier, Crystal & White Pass | Mt. Hood | ||
|---|---|---|---|---|---|---|---|---|---|
| Friday Evening | Snow Level * | 3500' | 3500' | 3500' | 4500' | 4000' | 4000' | 5000' | 6000' |
| Friday Night | Snow Level * | 3000' | 4000' | 3500' | 4500' | 3500' | 4000' | 4500' | 6500' |
| Saturday Morning | Snow Level | 2500' | 2500' | 3500' | 4000' | 3500' | 3500' | 4000' | 4500' |
| Saturday Afternoon | Snow Level | 3000' | 2500' | 3000' | 3500' | 3000' | 3000' | 3500' | 4000' |
| Saturday Evening | Snow Level | 2500' | 2500' | 2500' | 4000' | 2500' | 2500' | 3000' | 3000' |
| Saturday Night | Snow Level | 2500' | 2000' | 2000' | 3000' | 2500' | 2500' | 2500' | 2500' |
| Sunday Morning | Snow Level * | 3000' | 2500' | 2000' | 2000' | 2500' | 2500' | 2500' | 2500' |
| Sunday Afternoon | Snow Level | 3000' | 2500' | 2000' | 2000' | 2500' | 3000' | 3000' | 3000' |
| Hurricane Ridge | Elevation |
|---|---|
| Friday Evening |
Snow Level 3500' (Easterly Flow *) |
| Friday Night |
Snow Level 3000' (Easterly Flow *) |
| Saturday Morning |
Snow Level 2500' |
| Saturday Afternoon |
Snow Level 3000' |
| Saturday Evening |
Snow Level 2500' |
| Saturday Night |
Snow Level 2500' |
| Sunday Morning |
Snow Level 3000' (Easterly Flow *) |
| Sunday Afternoon |
Snow Level 3000' |
| Mt. Baker | Elevation |
|---|---|
| Friday Evening |
Snow Level 3500' (Easterly Flow *) |
| Friday Night |
Snow Level 4000' (Easterly Flow *) |
| Saturday Morning |
Snow Level 2500' |
| Saturday Afternoon |
Snow Level 2500' |
| Saturday Evening |
Snow Level 2500' |
| Saturday Night |
Snow Level 2000' |
| Sunday Morning |
Snow Level 2500' (Easterly Flow *) |
| Sunday Afternoon |
Snow Level 2500' |
| Washington Pass | Elevation |
|---|---|
| Friday Evening |
Snow Level 3500' (Easterly Flow *) |
| Friday Night |
Snow Level 3500' (Easterly Flow *) |
| Saturday Morning |
Snow Level 3500' |
| Saturday Afternoon |
Snow Level 3000' |
| Saturday Evening |
Snow Level 2500' |
| Saturday Night |
Snow Level 2000' |
| Sunday Morning |
Snow Level 2000' (Easterly Flow *) |
| Sunday Afternoon |
Snow Level 2000' |
| Leavenworth | Elevation |
|---|---|
| Friday Evening |
Snow Level 4500' (Easterly Flow *) |
| Friday Night |
Snow Level 4500' (Easterly Flow *) |
| Saturday Morning |
Snow Level 4000' |
| Saturday Afternoon |
Snow Level 3500' |
| Saturday Evening |
Snow Level 4000' |
| Saturday Night |
Snow Level 3000' |
| Sunday Morning |
Snow Level 2000' (Easterly Flow *) |
| Sunday Afternoon |
Snow Level 2000' |
| Stevens Pass | Elevation |
|---|---|
| Friday Evening |
Snow Level 4000' (Easterly Flow *) |
| Friday Night |
Snow Level 3500' (Easterly Flow *) |
| Saturday Morning |
Snow Level 3500' |
| Saturday Afternoon |
Snow Level 3000' |
| Saturday Evening |
Snow Level 2500' |
| Saturday Night |
Snow Level 2500' |
| Sunday Morning |
Snow Level 2500' (Easterly Flow *) |
| Sunday Afternoon |
Snow Level 2500' |
| Snoqualmie Pass | Elevation |
|---|---|
| Friday Evening |
Snow Level 4000' (Easterly Flow *) |
| Friday Night |
Snow Level 4000' (Easterly Flow *) |
| Saturday Morning |
Snow Level 3500' |
| Saturday Afternoon |
Snow Level 3000' |
| Saturday Evening |
Snow Level 2500' |
| Saturday Night |
Snow Level 2500' |
| Sunday Morning |
Snow Level 2500' (Easterly Flow *) |
| Sunday Afternoon |
Snow Level 3000' |
| Mt. Rainier & Crystal | Elevation |
|---|---|
| Friday Evening |
Snow Level 5000' (Easterly Flow *) |
| Friday Night |
Snow Level 4500' (Easterly Flow *) |
| Saturday Morning |
Snow Level 4000' |
| Saturday Afternoon |
Snow Level 3500' |
| Saturday Evening |
Snow Level 3000' |
| Saturday Night |
Snow Level 2500' |
| Sunday Morning |
Snow Level 2500' (Easterly Flow *) |
| Sunday Afternoon |
Snow Level 3000' |
| Mt. Hood | Elevation |
|---|---|
| Friday Evening |
Snow Level 6000' (Easterly Flow *) |
| Friday Night |
Snow Level 6500' (Easterly Flow *) |
| Saturday Morning |
Snow Level 4500' |
| Saturday Afternoon |
Snow Level 4000' |
| Saturday Evening |
Snow Level 3000' |
| Saturday Night |
Snow Level 2500' |
| Sunday Morning |
Snow Level 2500' (Easterly Flow *) |
| Sunday Afternoon |
Snow Level 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.
Precipitation Forecast
| Friday Night | Tuesday | Tuesday Night | Tuesday | |
|---|---|---|---|---|
| 4 pm - 4 am | 4 am - 4 pm | 4 pm - 4 am | 4 am - 4 pm | |
| Hurricane Ridge | 0.50 - 0.75 | LT 0.10 | LT 0.10 | 0 |
| Mt Baker Ski Area | 1.50 | 0.50 | 0 | 0 |
| Washington Pass | 0.75 | 0.25 - 0.50 | 0 | 0 |
| Leavenworth | 0.25 | LT 0.10 | 0 | 0 |
| Stevens Pass | 0.75 | 0.25 - 0.50 | LT 0.10 | 0 |
| Snoqualmie Pass | 0.75 -1.00 | 0.50 | LT 0.10 | 0 |
| Mission Ridge | 0.25 | LT 0.25 | 0 | 0 |
| Crystal Mt | 1.50 - 2.00 | 0.50 | LT 0.10 | 0 |
| Paradise | 1.50 - 2.00 | 0.75 -1.00 | LT 0.10 | LT 0.10 |
| White Pass | 0.75 -1.00 | 0.50 | LT 0.10 | LT 0.10 |
| Mt Hood Meadows | LT 0.10 | 0.75 | LT 0.10 | LT 0.10 |
| Timberline | LT 0.10 | 0.75 -1.00 | LT 0.10 | LT 0.10 |
| Hurricane Ridge | Precipitation Forecast |
|---|---|
| Friday Night | 0.50 - 0.75 |
| Tuesday | LT 0.10 |
| Tuesday Night | LT 0.10 |
| Tuesday | 0 |
| Mt Baker Ski Area | Precipitation Forecast |
|---|---|
| Friday Night | 1.50 |
| Tuesday | 0.50 |
| Tuesday Night | 0 |
| Tuesday | 0 |
| Washington Pass | Precipitation Forecast |
|---|---|
| Friday Night | 0.75 |
| Tuesday | 0.25 - 0.50 |
| Tuesday Night | 0 |
| Tuesday | 0 |
| Leavenworth | Precipitation Forecast |
|---|---|
| Friday Night | 0.25 |
| Tuesday | LT 0.10 |
| Tuesday Night | 0 |
| Tuesday | 0 |
| Stevens Pass | Precipitation Forecast |
|---|---|
| Friday Night | 0.75 |
| Tuesday | 0.25 - 0.50 |
| Tuesday Night | LT 0.10 |
| Tuesday | 0 |
| Snoqualmie Pass | Precipitation Forecast |
|---|---|
| Friday Night | 0.75 -1.00 |
| Tuesday | 0.50 |
| Tuesday Night | LT 0.10 |
| Tuesday | 0 |
| Mission Ridge | Precipitation Forecast |
|---|---|
| Friday Night | 0.25 |
| Tuesday | LT 0.25 |
| Tuesday Night | 0 |
| Tuesday | 0 |
| Crystal Mt | Precipitation Forecast |
|---|---|
| Friday Night | 1.50 - 2.00 |
| Tuesday | 0.50 |
| Tuesday Night | LT 0.10 |
| Tuesday | 0 |
| Paradise | Precipitation Forecast |
|---|---|
| Friday Night | 1.50 - 2.00 |
| Tuesday | 0.75 -1.00 |
| Tuesday Night | LT 0.10 |
| Tuesday | LT 0.10 |
| White Pass | Precipitation Forecast |
|---|---|
| Friday Night | 0.75 -1.00 |
| Tuesday | 0.50 |
| Tuesday Night | LT 0.10 |
| Tuesday | LT 0.10 |
| Mt Hood Meadows | Precipitation Forecast |
|---|---|
| Friday Night | LT 0.10 |
| Tuesday | 0.75 |
| Tuesday Night | LT 0.10 |
| Tuesday | LT 0.10 |
| Timberline | Precipitation Forecast |
|---|---|
| Friday Night | LT 0.10 |
| Tuesday | 0.75 -1.00 |
| Tuesday Night | LT 0.10 |
| Tuesday | 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: 2:43 PM PST Friday, December 20, 2019
Free Winds at 5000' (mph)
| Hurricane Ridge | Mt. Baker | Stevens to Snoqualmie Pass | Mt. Rainier | Mt. Hood | |
|---|---|---|---|---|---|
| Friday Evening | WSW 5 - 15 | S 15 - 25 | S 20 - 30 | SSW 20 - 30 | SSW 30 - 40 |
| Friday Night | W 5 - 15 | SW 5 - 15 | SSW 10 - 20 | SW 15 - 25 | SW 20 - 30 |
| Saturday Morning | W 5 - 15 | WSW 0 - 10 | W 5 - 15 | SSW 5 - 15 | WSW 20 - 30 |
| Saturday Afternoon | SW 5 - 15 | WSW 0 - 10 | W 5 - 15 | W 5 - 15 | W 10 - 20 |
| Hurricane Ridge | Elevation |
|---|---|
| Friday Evening | WSW 5 - 15 |
| Friday Night | W 5 - 15 |
| Saturday Morning | W 5 - 15 |
| Saturday Afternoon | SW 5 - 15 |
| Mt. Baker | Elevation |
|---|---|
| Friday Evening | S 15 - 25 |
| Friday Night | SW 5 - 15 |
| Saturday Morning | WSW 0 - 10 |
| Saturday Afternoon | WSW 0 - 10 |
| Stevens and Snoqualmie Pass | Elevation |
|---|---|
| Friday Evening | S 20 - 30 |
| Friday Night | SSW 10 - 20 |
| Saturday Morning | W 5 - 15 |
| Saturday Afternoon | W 5 - 15 |
| Mt. Rainier | Elevation |
|---|---|
| Friday Evening | SSW 20 - 30 |
| Friday Night | SW 15 - 25 |
| Saturday Morning | SSW 5 - 15 |
| Saturday Afternoon | W 5 - 15 |
| Mt. Hood | Elevation |
|---|---|
| Friday Evening | SSW 30 - 40 |
| Friday Night | SW 20 - 30 |
| Saturday Morning | WSW 20 - 30 |
| Saturday Afternoon | W 10 - 20 |
| Hurricane Ridge | Direction - Speed |
|---|---|
| Friday Evening | WSW 5 - 15 |
| Friday Night | W 5 - 15 |
| Saturday Morning | W 5 - 15 |
| Saturday Afternoon | SW 5 - 15 |
| Mt. Baker | Direction - Speed |
|---|---|
| Friday Evening | S 15 - 25 |
| Friday Night | SW 5 - 15 |
| Saturday Morning | WSW 0 - 10 |
| Saturday Afternoon | WSW 0 - 10 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Friday Evening | S 20 - 30 |
| Friday Night | SSW 10 - 20 |
| Saturday Morning | W 5 - 15 |
| Saturday Afternoon | W 5 - 15 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Friday Evening | SSW 20 - 30 |
| Friday Night | SW 15 - 25 |
| Saturday Morning | SSW 5 - 15 |
| Saturday Afternoon | W 5 - 15 |
| Mt. Hood | Direction - Speed |
|---|---|
| Friday Evening | SSW 30 - 40 |
| Friday Night | SW 20 - 30 |
| Saturday Morning | WSW 20 - 30 |
| Saturday Afternoon | W 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 | |
|---|---|---|---|---|---|
| Friday Evening | SSW 30 - 40 | SW 35 - 45 | SW 50 - 70 | SW 55 - 75 | SW 50 - 70 |
| Friday Night | SSW 20 - 30 | SSW 20 - 30 | SW 40 - 60 | SW 45 - 65 | SW 60 - 80 |
| Saturday Morning | SSW 15 - 25 | SSW 10 - 20 | SW 40 - 60 | SW 30 - 40 | SW 55 - 75 |
| Saturday Afternoon | W 10 - 20 | W 10 - 20 | W 20 - 30 | WSW 15 - 25 | SW 35 - 45 |
| Mt. Baker | Direction - Speed |
|---|---|
| Friday Evening | SSW 30 - 40 |
| Friday Night | SSW 20 - 30 |
| Saturday Morning | SSW 15 - 25 |
| Saturday Afternoon | W 10 - 20 |
| Washington Pass | Direction - Speed |
|---|---|
| Friday Evening | SW 35 - 45 |
| Friday Night | SSW 20 - 30 |
| Saturday Morning | SSW 10 - 20 |
| Saturday Afternoon | W 10 - 20 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Friday Evening | SW 50 - 70 |
| Friday Night | SW 40 - 60 |
| Saturday Morning | SW 40 - 60 |
| Saturday Afternoon | W 20 - 30 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Friday Evening | SW 55 - 75 |
| Friday Night | SW 45 - 65 |
| Saturday Morning | SW 30 - 40 |
| Saturday Afternoon | WSW 15 - 25 |
| Mt. Hood | Direction - Speed |
|---|---|
| Friday Evening | SW 50 - 70 |
| Friday Night | SW 60 - 80 |
| Saturday Morning | SW 55 - 75 |
| Saturday Afternoon | SW 35 - 45 |
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: 2:43 PM PST Friday, December 20, 2019
Extended Weather Synopsis for Tuesday night through Tuesday
The trough remains over the region Sunday night and Monday with cold temperatures and a slight chance of light snow showers. A weak ridge moves over the region Monday night with a weak system bringing clouds and light precipitation into our coastal waters on Tuesday.
Extended Snow/Freezing Levels
| Mt. Baker | Snoqualmie Pass | Mt. Hood | Easterly Flow * | ||
|---|---|---|---|---|---|
| Sunday Night | Snow Level | 1000' - 2000' | 1500' - 2500' | 2000' - 3000' | |
| Monday | Freezing Level | 1500' - 2500' | 2000' - 3000' | 2500' - 3500' | |
| Monday Night | Freezing Level | 1000' - 2000' | 1000' - 2000' | 1000' - 2000' | |
| Tuesday | Freezing Level | 500' - 1500' | 1000' - 2000' | 1500' - 2500' |
| Mt. Baker | Elevation |
|---|---|
| Sunday Night |
Snow Level 1000' - 2000' |
| Monday |
Freezing Level 1500' - 2500' |
| Monday Night |
Freezing Level 1000' - 2000' |
| Tuesday |
Freezing Level 500' - 1500' |
| Snoqualmie Pass | Elevation |
|---|---|
| Sunday Night |
Snow Level 1500' - 2500' |
| Monday |
Freezing Level 2000' - 3000' |
| Monday Night |
Freezing Level 1000' - 2000' |
| Tuesday |
Freezing Level 1000' - 2000' |
| Mt. Hood | Elevation |
|---|---|
| Sunday Night |
Snow Level 2000' - 3000' |
| Monday |
Freezing Level 2500' - 3500' |
| Monday Night |
Freezing Level 1000' - 2000' |
| Tuesday |
Freezing Level 1500' - 2500' |
* 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 20, 2019
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.