It's a mild Sunday afternoon in the mountains with temperatures in the mid 30s to mid 40s from the Canadian border to Mt Hood under partly sunny skies. The upper level ridge responsible for the dry and mild weather on Sunday will migrate inland Sunday night. A low pressure system winding into the central/northern B.C. coast Sunday night will bring increasing clouds from NW to SE across the region on Monday along with light precipitation (mostly rain) to the Olympics and northwest Cascades by mid-day.
The frontal band is forecast to move through Monday evening with a widespread burst of light to moderate precipitation across the area. The trailing shortwave trough behind the frontal boundary will likely inject additional moisture into the area in the form of showers through much of Tuesday. Snow levels will fall rapidly with the upper trough on Tuesday morning with accumulating snow at 3000' or lower by daybreak. Winds will become brisk out of the WNW late Monday night through Tuesday and a Puget Sound Convergence Zone is likely to form in the central Cascades as well.
Weather Forecast
Olympics
West North
West Central
West South
Stevens Pass
Snoqualmie Pass
East North
East Central
East South
Mt. Hood
Use dropdown to select your zone
Sunday
Night
Partly cloudy to mostly clear with periods of high clouds.
Monday
Mostly cloudy in the morning. Becoming cloudy mid-day with light rain and snow developing. Moderate to strong winds developing.
Sunday
Night
Partly cloudy to mostly clear with periods of high clouds.
Monday
Mostly cloudy in the morning. Becoming cloudy mid-day with light rain and snow developing. Strong winds.
Sunday
Night
Partly cloudy to mostly clear with periods of high clouds.
Monday
Partly to mostly cloudy in the morning. Becoming cloudy in mid-day with light rain and snow developing in the afternoon.
Sunday
Night
Partly cloudy to mostly clear with periods of high clouds.
Monday
Mostly sunny in the morning then becoming mostly cloudy in the afternoon.
Sunday
Night
Partly cloudy to mostly clear with periods of high clouds. Light east winds at Pass level.
Monday
Partly to mostly cloudy in the morning then becoming cloudy in the afternoon. Light east winds at Pass level.
Sunday
Night
Partly cloudy to mostly clear with periods of high clouds. Light to moderate east winds at Pass level.
Monday
Partly sunny in the morning then becoming cloudy in the afternoon. Light east winds at Pass level.
Sunday
Night
Partly cloudy to mostly clear with periods of high clouds.
Monday
Partly sunny in the morning then becoming cloudy in the afternoon. Chance of light rain or snow late.
Sunday
Night
Partly cloudy to mostly clear with periods of high clouds.
Monday
Mostly sunny in the morning then becoming mostly cloudy in the afternoon.
Sunday
Night
Partly cloudy to mostly clear with periods of high clouds.
Monday
Mostly sunny in the morning then becoming partly cloudy in the afternoon.
Sunday
Night
Partly cloudy to mostly clear with periods of high clouds.
Monday
Mostly sunny in the morning then becoming partly cloudy in the afternoon.
Issued: 1:59 PM PST Sunday, November 21, 2021
Precipitation (in)
Sunday Night
Monday
Monday Night
Tuesday
4 pm - 4 am
4 am - 4 pm
4 pm - 4 am
4 am - 4 pm
Hurricane Ridge
0
LT 0.10
0.25
LT 0.10
Mt Baker Ski Area
0
LT 0.10
0.50 - 0.75
LT 0.25
Mt. Loop - Barlow Pass
0
LT 0.10
0.75
0.25
Stevens Pass
0
0
0.50
LT 0.25
Snoqualmie Pass
0
0
0.50
0.25 - 0.50
Crystal Mt
0
0
LT 0.25
0.25
Paradise
0
0
0.50
0.50
White Pass
0
0
0.25
LT 0.25
Washington Pass
0
0
0.25
LT 0.10
Mission Ridge
0
0
LT 0.10
LT 0.10
Salmon la Sac - Gallagher Head
0
0
0.25
0.25
Tieton River - Darland Mt.
0
0
LT 0.10
LT 0.10
Mt Hood Meadows
0
0
LT 0.25
0.25 - 0.50
Timberline
0
0
0.25
0.50
Hurricane Ridge
Precipitation (in)
Sunday Night
0
Monday
LT 0.10
Monday Night
0.25
Tuesday
LT 0.10
Mt Baker Ski Area
Precipitation (in)
Sunday Night
0
Monday
LT 0.10
Monday Night
0.50 - 0.75
Tuesday
LT 0.25
Mt. Loop - Barlow Pass
Precipitation (in)
Sunday Night
0
Monday
LT 0.10
Monday Night
0.75
Tuesday
0.25
Stevens Pass
Precipitation (in)
Sunday Night
0
Monday
0
Monday Night
0.50
Tuesday
LT 0.25
Snoqualmie Pass
Precipitation (in)
Sunday Night
0
Monday
0
Monday Night
0.50
Tuesday
0.25 - 0.50
Crystal Mt
Precipitation (in)
Sunday Night
0
Monday
0
Monday Night
LT 0.25
Tuesday
0.25
Paradise
Precipitation (in)
Sunday Night
0
Monday
0
Monday Night
0.50
Tuesday
0.50
White Pass
Precipitation (in)
Sunday Night
0
Monday
0
Monday Night
0.25
Tuesday
LT 0.25
Washington Pass
Precipitation (in)
Sunday Night
0
Monday
0
Monday Night
0.25
Tuesday
LT 0.10
Mission Ridge
Precipitation (in)
Sunday Night
0
Monday
0
Monday Night
LT 0.10
Tuesday
LT 0.10
Salmon la Sac - Gallagher Head
Precipitation (in)
Sunday Night
0
Monday
0
Monday Night
0.25
Tuesday
0.25
Tieton River - Darland Mt.
Precipitation (in)
Sunday Night
0
Monday
0
Monday Night
LT 0.10
Tuesday
LT 0.10
Mt Hood Meadows
Precipitation (in)
Sunday Night
0
Monday
0
Monday Night
LT 0.25
Tuesday
0.25 - 0.50
Timberline
Precipitation (in)
Sunday Night
0
Monday
0
Monday Night
0.25
Tuesday
0.50
Issued: 1:59 PM PST Sunday, November 21, 2021
Snow Level (ft)
Sunday
Evening
Sunday
Night
Monday
Morning
Monday
Afternoon
Monday
Evening
Monday
Night
Tuesday
Morning
Tuesday
Afternoon
Olympics
10000'
9000'
7500'
5000'
3500'
3000'
2500'
2500'
West North
7500'
7000'
6500'
5000'
3500'
3000'
2500'
2500'
West Central
8500'
8500'
7500'
6000'
3500'
3000'
2500'
2500'
West South
11000'
9000'
7500'
7000'
4000'
3000'
2500'
2500'
Stevens Pass
9000'
9000'
8000'
7000'
3500'
3000'
2500'
2500'
Snoqualmie Pass
10000'
9000'
8000'
7000'
3500'
3000'
2500'
2500'
East North
8000'
8000'
7500'
5000'
3000'
3000'
2500'
2000'
East Central
8500'
8000'
8000'
6000'
4000'
3000'
2500'
2500'
East South
10000'
9000'
9000'
8000'
4000'
3500'
3000'
2500'
Mt. Hood
12000'
11000'
10000'
9000'
4500'
3500'
3500'
3000'
Olympics
Elevation
Sunday
Evening
10000'
Sunday
Night
9000'
Monday
Morning
7500'
Monday
Afternoon
5000'
Monday
Evening
3500'
Monday
Night
3000'
Tuesday
Morning
2500'
Tuesday
Afternoon
2500'
West North
Elevation
Sunday
Evening
7500'
Sunday
Night
7000'
Monday
Morning
6500'
Monday
Afternoon
5000'
Monday
Evening
3500'
Monday
Night
3000'
Tuesday
Morning
2500'
Tuesday
Afternoon
2500'
West Central
Elevation
Sunday
Evening
8500'
Sunday
Night
8500'
Monday
Morning
7500'
Monday
Afternoon
6000'
Monday
Evening
3500'
Monday
Night
3000'
Tuesday
Morning
2500'
Tuesday
Afternoon
2500'
West South
Elevation
Sunday
Evening
11000'
Sunday
Night
9000'
Monday
Morning
7500'
Monday
Afternoon
7000'
Monday
Evening
4000'
Monday
Night
3000'
Tuesday
Morning
2500'
Tuesday
Afternoon
2500'
Stevens Pass
Elevation
Sunday
Evening
9000'
Sunday
Night
9000'
Monday
Morning
8000'
Monday
Afternoon
7000'
Monday
Evening
3500'
Monday
Night
3000'
Tuesday
Morning
2500'
Tuesday
Afternoon
2500'
Snoqualmie Pass
Elevation
Sunday
Evening
10000'
Sunday
Night
9000'
Monday
Morning
8000'
Monday
Afternoon
7000'
Monday
Evening
3500'
Monday
Night
3000'
Tuesday
Morning
2500'
Tuesday
Afternoon
2500'
East North
Elevation
Sunday
Evening
8000'
Sunday
Night
8000'
Monday
Morning
7500'
Monday
Afternoon
5000'
Monday
Evening
3000'
Monday
Night
3000'
Tuesday
Morning
2500'
Tuesday
Afternoon
2000'
East Central
Elevation
Sunday
Evening
8500'
Sunday
Night
8000'
Monday
Morning
8000'
Monday
Afternoon
6000'
Monday
Evening
4000'
Monday
Night
3000'
Tuesday
Morning
2500'
Tuesday
Afternoon
2500'
East South
Elevation
Sunday
Evening
10000'
Sunday
Night
9000'
Monday
Morning
9000'
Monday
Afternoon
8000'
Monday
Evening
4000'
Monday
Night
3500'
Tuesday
Morning
3000'
Tuesday
Afternoon
2500'
Mt. Hood
Elevation
Sunday
Evening
12000'
Sunday
Night
11000'
Monday
Morning
10000'
Monday
Afternoon
9000'
Monday
Evening
4500'
Monday
Night
3500'
Tuesday
Morning
3500'
Tuesday
Afternoon
3000'
Issued: 1:59 PM PST Sunday, November 21, 2021
5000' Temperatures (°F)
Sunday
Night
Monday
Max / Min
Max / Min
Olympics
40 / 34
34 / 32
West North
37 / 35
35 / 29
West Central
38 / 36
36 / 31
West South
40 / 38
41 / 35
Stevens Pass
38 / 36
38 / 33
Snoqualmie Pass
39 / 36
38 / 33
East North
36 / 33
37 / 31
East Central
40 / 36
39 / 34
East South
41 / 38
42 / 35
Mt. Hood
41 / 38
45 / 39
Olympics
5000' Temperature Forecast (Max / Min)
Sunday
Night
40 / 34
Monday
34 / 32
West North
5000' Temperature Forecast (Max / Min)
Sunday
Night
37 / 35
Monday
35 / 29
West Central
5000' Temperature Forecast (Max / Min)
Sunday
Night
38 / 36
Monday
36 / 31
West South
5000' Temperature Forecast (Max / Min)
Sunday
Night
40 / 38
Monday
41 / 35
Stevens Pass
5000' Temperature Forecast (Max / Min)
Sunday
Night
38 / 36
Monday
38 / 33
Snoqualmie Pass
5000' Temperature Forecast (Max / Min)
Sunday
Night
39 / 36
Monday
38 / 33
East North
5000' Temperature Forecast (Max / Min)
Sunday
Night
36 / 33
Monday
37 / 31
East Central
5000' Temperature Forecast (Max / Min)
Sunday
Night
40 / 36
Monday
39 / 34
East South
5000' Temperature Forecast (Max / Min)
Sunday
Night
41 / 38
Monday
42 / 35
Mt. Hood
5000' Temperature Forecast (Max / Min)
Sunday
Night
41 / 38
Monday
45 / 39
Issued: 1:59 PM PST Sunday, November 21, 2021
Ridgeline Winds (mph)
Sunday
Evening
Sunday
Night
Monday
Morning
Monday
Afternoon
Olympics
SW 5-15
SSW 15-25
S 20-30
SW 20-30
West North
SW 10-20
SSW 15-25
S 20-30
S 25-35
West Central
SW 5-15
SSW 5-15
SW 10-20
SW 15-25
West South
SSW 5-15
SW 5-15
SW 10-20
SW 15-25
Stevens Pass
SSW 5-15
S 5-15
SSW 5-15
SW 10-20
Snoqualmie Pass
SW 5-15
S 5-15
SSW 10-20
SW 15-25
East North
SW 15-25
SW 10-20
WSW 15-25
SW 20-30
East Central
WSW 10-20
WSW 5-15
WSW 10-20
WSW 15-25
East South
SW 10-20
WSW 5-15
WSW 10-20
WSW 15-25
Mt. Hood
SW 5-15
SW 10-20
SW 10-20
SW 15-25
Olympics
Ridgeline Winds (mph)
Sunday
Evening
SW
5-15
Sunday
Night
SSW
15-25
Monday
Morning
S
20-30
Monday
Afternoon
SW
20-30
West North
Ridgeline Winds (mph)
Sunday
Evening
SW
10-20
Sunday
Night
SSW
15-25
Monday
Morning
S
20-30
Monday
Afternoon
S
25-35
West Central
Ridgeline Winds (mph)
Sunday
Evening
SW
5-15
Sunday
Night
SSW
5-15
Monday
Morning
SW
10-20
Monday
Afternoon
SW
15-25
West South
Ridgeline Winds (mph)
Sunday
Evening
SSW
5-15
Sunday
Night
SW
5-15
Monday
Morning
SW
10-20
Monday
Afternoon
SW
15-25
Stevens Pass
Ridgeline Winds (mph)
Sunday
Evening
SSW
5-15
Sunday
Night
S
5-15
Monday
Morning
SSW
5-15
Monday
Afternoon
SW
10-20
Snoqualmie Pass
Ridgeline Winds (mph)
Sunday
Evening
SW
5-15
Sunday
Night
S
5-15
Monday
Morning
SSW
10-20
Monday
Afternoon
SW
15-25
East North
Ridgeline Winds (mph)
Sunday
Evening
SW
15-25
Sunday
Night
SW
10-20
Monday
Morning
WSW
15-25
Monday
Afternoon
SW
20-30
East Central
Ridgeline Winds (mph)
Sunday
Evening
WSW
10-20
Sunday
Night
WSW
5-15
Monday
Morning
WSW
10-20
Monday
Afternoon
WSW
15-25
East South
Ridgeline Winds (mph)
Sunday
Evening
SW
10-20
Sunday
Night
WSW
5-15
Monday
Morning
WSW
10-20
Monday
Afternoon
WSW
15-25
Mt. Hood
Ridgeline Winds (mph)
Sunday
Evening
SW
5-15
Sunday
Night
SW
10-20
Monday
Morning
SW
10-20
Monday
Afternoon
SW
15-25
Issued: 1:59 PM PST Sunday, November 21, 2021
Extended Weather Synopsis
We'll see shortwave ridging move Tuesday night and Wednesday, allowing dry conditions to take hold over the area. A stronger, wetter system will take aim at the Pacific Northwest Wednesday night first for the north Cascades and Olympics and shift south on Thanksgiving. The jet stream, the dividing line between warm and relatively colder air masses, looks like it will be aimed near the Canadian border for much of this event. Snow levels look fairly high in the central/south Washington Cascades and northern Oregon. We'll have to wait and see if there will be significant snow accumulations in the north Cascades (both sides of the crest) and just how high snow levels will push during this event.
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.
The 5000’ temperature forecast does not imply a trend over the 12 hr period and only represents the max and min temperatures within a 12 hr period in the zone. The 6-hr snow level forecast, the forecast discussion, and weather forecast sections may add detail regarding temperature trends.
The snow level forecast represents the general snow level over a 6 hr time period. Freezing levels are forecast when precipitation is not expected.
*Easterly or offshore flow is highlighted with an asterisk when we expect relatively cool east winds in the major Cascade Passes. Easterly flow will often lead to temperature inversions and is a key variable for forecasting precipitation type in the Cascade Passes. Strong easterly flow events can affect terrain on a more regional scale.
Ridgeline winds are the average wind speed and direction over a 6 hr time period.
The wind forecast represents an elevation range instead of a single elevation slice. The elevation range overlaps with the near and above treeline elevation bands in the avalanche forecast and differs per zone.
Wind direction indicates the direction the wind originates or comes from on the 16-point compass rose.
Water Equivalent (WE) is the liquid water equivalent of all precipitation types; rain, snow, ice pellets, etc., forecast to the hundredth of an inch at specific locations. To use WE as a proxy for snowfall amounts, start with a snow to water ratio of 10:1 (10 inches of snow = 1 inch WE). Temperatures at or near freezing will generally have a lower ratio (heavy wet snow) and very cold temperatures can have a much higher ratio (dry fluffy snow).