Jump to: Weather Forecast I Snow/Freezing Level I Precipitation I Free Winds 5k I Free Winds 9k I Extended Weather
Weather Synopsis for Monday night through Tuesday
On the heels of the previous system, a strong jet aimed at northern Oregon will bring a slow-moving major storm system into the Pacific Northwest, impacting all mountain regions with significant rain or snow and strong winds over the next 36 hours while the parent low temporarily stalls in the Gulf of Alaska.
Monday night, a warm front will pass through the region bringing heavy rain and high elevation snow along with increasing winds to many locations. Very stormy weather will continue during the day on Tuesday as the associated cold front slides E-SE during the late morning and mid-day hours. Snow levels will gradually lower as precipitation becomes post-frontal in character and winds shift from S-SW to W-SW, but remain moderate to strong. Tuesday night and Wednesday morning, cooler post-frontal rain and snow showers continue, but gradually decrease and end from south to north.
Weather Forecast
Hurricane Ridge
| Monday Night | Very stormy with moderate rain and high elevation snow, strong and potentially damaging winds, and rising snow levels. |
| Tuesday | Light rain and snow becoming showery in the afternoon. Moderate winds with strong gusts. Snow level gradually lowering. |
Mt. Baker
| Monday Night | Very stormy with rain and snow increasing during the early evening and becoming moderate to heavy. Strong winds. Rising snow levels. |
| Tuesday | Stormy with moderate to heavy rain and snow; moderate to strong winds; snow levels peaking in the late morning hours and then decreasing. |
Washington Pass and Leavenworth
| Monday Night | Stormy with moderate snow; moderate winds gusting strong; gradually rising snow levels. |
| Tuesday | Stormy with moderate snow decreasing in the afternoon, moderate winds gusting strong. Snow levels peaking between 4000 and 5000 ft in the middle of the day, then decreasing. |
Stevens and Snoqualmie Pass
| Monday Night | Stormy with moderate to occasionally heavy snow at Snoqualmie Pass; light to moderate snow at Stevens Pass.; moderate winds gusting strong; gradually rising snow levels. Light to moderate easterly flow likely to keep Snoqualmie precipitation frozen. |
| Tuesday | Stormy with light to moderate snow decreasing and becoming showery in the afternoon, moderate winds increasing during the afternoon and gusting strong. Snow levels peaking between 4000 and 5000 ft in the middle of the day, then decreasing. |
Mt. Rainier, Crystal and White Pass
| Monday Night | Very stormy with increasing rain and snow becoming heavy for Paradise, Crystal, and White Passes. Rising snow levels. Moderate winds becoming strong after midnight. |
| Tuesday | Stormy with heavy rain and snow, strong winds, with snow levels rising in the morning and lowering in the afternoon. Moderate rain and snow showers in the afternoon with Crystal experiencing lighter showers. |
Mt. Hood
| Monday Night | Very stormy with increasing moderate rain and high elevation snow; rising snow levels; strong winds. |
| Tuesday | Very stormy with moderate rain and high elevation snow becoming moderate rain and snow showers. Strong and potentially damaging winds. |
Issued: 2:50 PM PST Monday, December 17, 2018
Snow/Freezing Level (ft)
| Hurricane Ridge | Mt. Baker | Washington Pass | Leavenworth | Stevens Pass | Snoqualmie Pass | Mt. Rainier, Crystal & White Pass | Mt. Hood | ||
|---|---|---|---|---|---|---|---|---|---|
| Monday Evening | Snow Level * | 4500' | 3500' | 3500' | 3500' | 3500' | 3500' | 4000' | 4500' |
| Monday Night | Snow Level * | 5500' | 3500' | 3000' | 3000' | 3500' | 4000' | 4500' | 6500' |
| Tuesday Morning | Snow Level | 5000' | 4000' | 3500' | 4500' | 4000' | 5000' | 5500' | 7000' |
| Tuesday Afternoon | Snow Level | 4000' | 4000' | 4000' | 4500' | 4000' | 4500' | 4500' | 5000' |
| Tuesday Evening | Snow Level | 3500' | 3500' | 4000' | 4000' | 3500' | 4000' | 4000' | 4500' |
| Tuesday Night | Snow Level | 3500' | 3000' | 3000' | 3500' | 3000' | 3000' | 3500' | 4000' |
| Wednesday Morning | Snow Level | 3500' | 3000' | 3000' | 3500' | 3000' | 3000' | 3000' | 3500' |
| Wednesday Afternoon | Snow Level | 3500' | 3500' | 3500' | 3500' | 3500' | 3500' | 3500' | 4000' |
| Hurricane Ridge | Elevation |
|---|---|
| Monday Evening |
Snow Level 4500' (Easterly Flow *) |
| Monday Night |
Snow Level 5500' (Easterly Flow *) |
| Tuesday Morning |
Snow Level 5000' |
| Tuesday Afternoon |
Snow Level 4000' |
| Tuesday Evening |
Snow Level 3500' |
| Tuesday Night |
Snow Level 3500' |
| Wednesday Morning |
Snow Level 3500' |
| Wednesday Afternoon |
Snow Level 3500' |
| Mt. Baker | Elevation |
|---|---|
| Monday Evening |
Snow Level 3500' (Easterly Flow *) |
| Monday Night |
Snow Level 3500' (Easterly Flow *) |
| Tuesday Morning |
Snow Level 4000' |
| Tuesday Afternoon |
Snow Level 4000' |
| Tuesday Evening |
Snow Level 3500' |
| Tuesday Night |
Snow Level 3000' |
| Wednesday Morning |
Snow Level 3000' |
| Wednesday Afternoon |
Snow Level 3500' |
| Washington Pass | Elevation |
|---|---|
| Monday Evening |
Snow Level 3500' (Easterly Flow *) |
| Monday Night |
Snow Level 3000' (Easterly Flow *) |
| Tuesday Morning |
Snow Level 3500' |
| Tuesday Afternoon |
Snow Level 4000' |
| Tuesday Evening |
Snow Level 4000' |
| Tuesday Night |
Snow Level 3000' |
| Wednesday Morning |
Snow Level 3000' |
| Wednesday Afternoon |
Snow Level 3500' |
| Leavenworth | Elevation |
|---|---|
| Monday Evening |
Snow Level 3500' (Easterly Flow *) |
| Monday Night |
Snow Level 3000' (Easterly Flow *) |
| Tuesday Morning |
Snow Level 4500' |
| Tuesday Afternoon |
Snow Level 4500' |
| Tuesday Evening |
Snow Level 4000' |
| Tuesday Night |
Snow Level 3500' |
| Wednesday Morning |
Snow Level 3500' |
| Wednesday Afternoon |
Snow Level 3500' |
| Stevens Pass | Elevation |
|---|---|
| Monday Evening |
Snow Level 3500' (Easterly Flow *) |
| Monday Night |
Snow Level 3500' (Easterly Flow *) |
| Tuesday Morning |
Snow Level 4000' |
| Tuesday Afternoon |
Snow Level 4000' |
| Tuesday Evening |
Snow Level 3500' |
| Tuesday Night |
Snow Level 3000' |
| Wednesday Morning |
Snow Level 3000' |
| Wednesday Afternoon |
Snow Level 3500' |
| Snoqualmie Pass | Elevation |
|---|---|
| Monday Evening |
Snow Level 3500' (Easterly Flow *) |
| Monday Night |
Snow Level 4000' (Easterly Flow *) |
| Tuesday Morning |
Snow Level 5000' |
| Tuesday Afternoon |
Snow Level 4500' |
| Tuesday Evening |
Snow Level 4000' |
| Tuesday Night |
Snow Level 3000' |
| Wednesday Morning |
Snow Level 3000' |
| Wednesday Afternoon |
Snow Level 3500' |
| Mt. Rainier & Crystal | Elevation |
|---|---|
| Monday Evening |
Snow Level 4000' (Easterly Flow *) |
| Monday Night |
Snow Level 4500' (Easterly Flow *) |
| Tuesday Morning |
Snow Level 5500' |
| Tuesday Afternoon |
Snow Level 4500' |
| Tuesday Evening |
Snow Level 4000' |
| Tuesday Night |
Snow Level 3500' |
| Wednesday Morning |
Snow Level 3000' |
| Wednesday Afternoon |
Snow Level 3500' |
| Mt. Hood | Elevation |
|---|---|
| Monday Evening |
Snow Level 4500' (Easterly Flow *) |
| Monday Night |
Snow Level 6500' (Easterly Flow *) |
| Tuesday Morning |
Snow Level 7000' |
| Tuesday Afternoon |
Snow Level 5000' |
| Tuesday Evening |
Snow Level 4500' |
| Tuesday Night |
Snow Level 4000' |
| Wednesday Morning |
Snow Level 3500' |
| Wednesday Afternoon |
Snow Level 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.
Precipitation Forecast
| Monday 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 0.25 | 0.25 | LT 0.10 |
| Mt Baker Ski Area | 2.00 | 0.75 -1.00 | 0.50 | 0.25 |
| Washington Pass | 1.00 | 0.75 -1.00 | 0.50 - 0.75 | 0.25 |
| Leavenworth | 0.50 | 0.25 - 0.50 | 0.25 | LT 0.10 |
| Stevens Pass | 0.50 | 0.50 - 0.75 | 0.50 | 0.25 |
| Snoqualmie Pass | 1.00 - 1.50 | 1.00 | 0.75 | 0.25 |
| Mission Ridge | 1.00 - 1.50 | 0.50 | LT 0.25 | 0 |
| Crystal Mt | 1.50 - 2.00 | 0.75 | 0.25 | LT 0.10 |
| Paradise | 2.00 | 1.50 | 1.00 | LT 0.25 |
| White Pass | 1.00 | 1.00 | 0.75 | LT 0.10 |
| Mt Hood Meadows | 1.00 | 1.00 - 1.50 | 0.75 | 0 |
| Timberline | 1.00 | 1.50 | 0.75 | 0 |
| Hurricane Ridge | Precipitation Forecast |
|---|---|
| Monday Night | 0.50 - 0.75 |
| Tuesday | LT 0.25 |
| Tuesday Night | 0.25 |
| Tuesday | LT 0.10 |
| Mt Baker Ski Area | Precipitation Forecast |
|---|---|
| Monday Night | 2.00 |
| Tuesday | 0.75 -1.00 |
| Tuesday Night | 0.50 |
| Tuesday | 0.25 |
| Washington Pass | Precipitation Forecast |
|---|---|
| Monday Night | 1.00 |
| Tuesday | 0.75 -1.00 |
| Tuesday Night | 0.50 - 0.75 |
| Tuesday | 0.25 |
| Leavenworth | Precipitation Forecast |
|---|---|
| Monday Night | 0.50 |
| Tuesday | 0.25 - 0.50 |
| Tuesday Night | 0.25 |
| Tuesday | LT 0.10 |
| Stevens Pass | Precipitation Forecast |
|---|---|
| Monday Night | 0.50 |
| Tuesday | 0.50 - 0.75 |
| Tuesday Night | 0.50 |
| Tuesday | 0.25 |
| Snoqualmie Pass | Precipitation Forecast |
|---|---|
| Monday Night | 1.00 - 1.50 |
| Tuesday | 1.00 |
| Tuesday Night | 0.75 |
| Tuesday | 0.25 |
| Mission Ridge | Precipitation Forecast |
|---|---|
| Monday Night | 1.00 - 1.50 |
| Tuesday | 0.50 |
| Tuesday Night | LT 0.25 |
| Tuesday | 0 |
| Crystal Mt | Precipitation Forecast |
|---|---|
| Monday Night | 1.50 - 2.00 |
| Tuesday | 0.75 |
| Tuesday Night | 0.25 |
| Tuesday | LT 0.10 |
| Paradise | Precipitation Forecast |
|---|---|
| Monday Night | 2.00 |
| Tuesday | 1.50 |
| Tuesday Night | 1.00 |
| Tuesday | LT 0.25 |
| White Pass | Precipitation Forecast |
|---|---|
| Monday Night | 1.00 |
| Tuesday | 1.00 |
| Tuesday Night | 0.75 |
| Tuesday | LT 0.10 |
| Mt Hood Meadows | Precipitation Forecast |
|---|---|
| Monday Night | 1.00 |
| Tuesday | 1.00 - 1.50 |
| Tuesday Night | 0.75 |
| Tuesday | 0 |
| Timberline | Precipitation Forecast |
|---|---|
| Monday Night | 1.00 |
| Tuesday | 1.50 |
| Tuesday Night | 0.75 |
| Tuesday | 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: 2:50 PM PST Monday, December 17, 2018
Free Winds at 5000' (mph)
| Hurricane Ridge | Mt. Baker | Stevens to Snoqualmie Pass | Mt. Rainier | Mt. Hood | |
|---|---|---|---|---|---|
| Monday Evening | S 45 - 65 | SE 35 - 50 | SE 30 - 45 | SSE 30 - 45 | S 40 - 60 |
| Monday Night | SE 25 - 35 | SSW 25 - 35 | SSW 35 - 50 | SSW 35 - 50 | SSW 45 - 65 |
| Tuesday Morning | SW 25 - 35 | SSE 15 - 25 | S 20 - 30 | SSW 20 - 30 | SW 40 - 60 |
| Tuesday Afternoon | SW 25 - 35 | SW 20 - 30 | WSW 30 - 45 | WSW 30 - 45 | WSW 40 - 60 |
| Hurricane Ridge | Elevation |
|---|---|
| Monday Evening | S 45 - 65 |
| Monday Night | SE 25 - 35 |
| Tuesday Morning | SW 25 - 35 |
| Tuesday Afternoon | SW 25 - 35 |
| Mt. Baker | Elevation |
|---|---|
| Monday Evening | SE 35 - 50 |
| Monday Night | SSW 25 - 35 |
| Tuesday Morning | SSE 15 - 25 |
| Tuesday Afternoon | SW 20 - 30 |
| Stevens and Snoqualmie Pass | Elevation |
|---|---|
| Monday Evening | SE 30 - 45 |
| Monday Night | SSW 35 - 50 |
| Tuesday Morning | S 20 - 30 |
| Tuesday Afternoon | WSW 30 - 45 |
| Mt. Rainier | Elevation |
|---|---|
| Monday Evening | SSE 30 - 45 |
| Monday Night | SSW 35 - 50 |
| Tuesday Morning | SSW 20 - 30 |
| Tuesday Afternoon | WSW 30 - 45 |
| Mt. Hood | Elevation |
|---|---|
| Monday Evening | S 40 - 60 |
| Monday Night | SSW 45 - 65 |
| Tuesday Morning | SW 40 - 60 |
| Tuesday Afternoon | WSW 40 - 60 |
| Hurricane Ridge | Direction - Speed |
|---|---|
| Monday Evening | S 45 - 65 |
| Monday Night | SE 25 - 35 |
| Tuesday Morning | SW 25 - 35 |
| Tuesday Afternoon | SW 25 - 35 |
| Mt. Baker | Direction - Speed |
|---|---|
| Monday Evening | SE 35 - 50 |
| Monday Night | SSW 25 - 35 |
| Tuesday Morning | SSE 15 - 25 |
| Tuesday Afternoon | SW 20 - 30 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Monday Evening | SE 30 - 45 |
| Monday Night | SSW 35 - 50 |
| Tuesday Morning | S 20 - 30 |
| Tuesday Afternoon | WSW 30 - 45 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Monday Evening | SSE 30 - 45 |
| Monday Night | SSW 35 - 50 |
| Tuesday Morning | SSW 20 - 30 |
| Tuesday Afternoon | WSW 30 - 45 |
| Mt. Hood | Direction - Speed |
|---|---|
| Monday Evening | S 40 - 60 |
| Monday Night | SSW 45 - 65 |
| Tuesday Morning | SW 40 - 60 |
| Tuesday Afternoon | WSW 40 - 60 |
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 | |
|---|---|---|---|---|---|
| Monday Evening | S 50 - 70 | SSW 35 - 50 | SW 45 - 65 | SW 50 - 70 | WSW 55 - 75 |
| Monday Night | SW 45 - 65 | SW 40 - 60 | SW 55 - 75 | SW 55 - 75 | SW 65 - 85 |
| Tuesday Morning | SW 25 - 35 | SW 35 - 50 | WSW 50 - 70 | SW 60 - 80 | SW 80 - 100 |
| Tuesday Afternoon | SW 40 - 60 | WSW 35 - 50 | WSW 55 - 75 | WSW 50 - 70 | WSW 65 - 85 |
| Mt. Baker | Direction - Speed |
|---|---|
| Monday Evening | S 50 - 70 |
| Monday Night | SW 45 - 65 |
| Tuesday Morning | SW 25 - 35 |
| Tuesday Afternoon | SW 40 - 60 |
| Washington Pass | Direction - Speed |
|---|---|
| Monday Evening | SSW 35 - 50 |
| Monday Night | SW 40 - 60 |
| Tuesday Morning | SW 35 - 50 |
| Tuesday Afternoon | WSW 35 - 50 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Monday Evening | SW 45 - 65 |
| Monday Night | SW 55 - 75 |
| Tuesday Morning | WSW 50 - 70 |
| Tuesday Afternoon | WSW 55 - 75 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Monday Evening | SW 50 - 70 |
| Monday Night | SW 55 - 75 |
| Tuesday Morning | SW 60 - 80 |
| Tuesday Afternoon | WSW 50 - 70 |
| Mt. Hood | Direction - Speed |
|---|---|
| Monday Evening | WSW 55 - 75 |
| Monday Night | SW 65 - 85 |
| Tuesday Morning | SW 80 - 100 |
| Tuesday Afternoon | WSW 65 - 85 |
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: 2:50 PM PST Monday, December 17, 2018
Extended Weather Synopsis for Tuesday night through Tuesday
Wednesday night, a compact and deeping low offshore will lift a warm front across the region, bringing rain and snow, heaviest over NW Washington.
The is currently forecast to make landfall near the northern tip of Vancouver Island on Thursday morning and may bring another round of strong winds, particularly to NW Washington on Thursday morning. The associated cold front will spread light to moderate rain and snow to all areas during the day on Thursday, with the heaviest rain and snow again over NW Washington.
This strong storm will bring rapid cooling behind the front with light snow showers and windy conditions following the front Thursday night.
Snow showers decrease and end Friday morning as weak ridging tries to gain a hold, with another frontal system poised offshore.
Extended Snow/Freezing Levels
| Mt. Baker | Snoqualmie Pass | Mt. Hood | Easterly Flow * | ||
|---|---|---|---|---|---|
| Wednesday Night | Snow Level | 2500' - 3500' | 3500' - 5500' | 6500' - 7500' | * |
| Thursday | Snow Level | 4000' - 5000' | 5000' - 6000' | 6000' - 7500' | |
| Thursday Night | Snow Level | 2000' - 3500' | 2500' - 4000' | 3000' - 4500' | |
| Friday | Snow Level | 0' - 2000' | 0' - 2000' | 500' - 2500' |
| Mt. Baker | Elevation |
|---|---|
| Wednesday Night |
Snow Level 2500' - 3500' (Easterly Flow *) |
| Thursday |
Snow Level 4000' - 5000' |
| Thursday Night |
Snow Level 2000' - 3500' |
| Friday |
Snow Level 0' - 2000' |
| Snoqualmie Pass | Elevation |
|---|---|
| Wednesday Night |
Snow Level 3500' - 5500' (Easterly Flow *) |
| Thursday |
Snow Level 5000' - 6000' |
| Thursday Night |
Snow Level 2500' - 4000' |
| Friday |
Snow Level 0' - 2000' |
| Mt. Hood | Elevation |
|---|---|
| Wednesday Night |
Snow Level 6500' - 7500' (Easterly Flow *) |
| Thursday |
Snow Level 6000' - 7500' |
| Thursday Night |
Snow Level 3000' - 4500' |
| Friday |
Snow Level 500' - 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 17, 2018
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