It's a beautiful and warm April afternoon with widespread 50s and 60s found throughout the mountains this afternoon. The warm and dry weather continues thanks to a quasi-stationary upper level ridge that's been parked over the west coast of North America much of the week. There will be a few subtle changes this week as the ridge becomes squeezed between two upper level features. The first is a shortwave trough passing south through the Canadian Rockies tonight. This will glance our area, dragging some slightly cooler air primarily into the Northeast Cascades, a few mid-level clouds, and help kick up ridgeline and alpine N-E winds tonight. The strongest winds will likely occur over the Wenatchee mountains tonight.
The second feature will be a very weak frontal system offshore that runs into the ridge tomorrow. This should spread increasing high and mid clouds over the Olympics and Mt Hood areas late Monday afternoon. This may increase the lower level RH enough to help some afternoon cumulus develop over the Cascades tomorrow afternoon. Lower and mid-mountain temperatures will remain warm with highs only a few degrees cooler than Sunday. The freezing level will drop noticeably at upper elevations and sit in the 7000-8000' range through mid-week.
The ridge will weaken but remain intact as the frontal system becomes an open low and slides SE into Oregon/California Monday night. Freezing levels will be steady but there's more uncertainty around the cloud forecast for Tuesday. The best guess is that mid-level moisture increases on Tuesday leading to an increase in afternoon cumulus buildup.
Spring Schedule: The 7 am Mountain Weather Forecast is finished for the 2020-2021 season. The 230 pm Mountain Weather Forecast will continue daily through Sunday, May 2nd. Thanks for a great La Nina season!
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
Mostly clear.
Monday
Mostly sunny in the morning becoming partly sunny late in the afternoon.
Sunday
Night
Mostly clear.
Monday
Mostly sunny with a few cumulus clouds in the afternoon.
Sunday
Night
Mostly clear. Moderate ridgeline winds decreasing after midnight.
Monday
Mostly sunny with a few cumulus clouds in the afternoon.
Sunday
Night
Mostly clear. Moderate ridgeline winds decreasing after midnight.
Monday
Mostly sunny with a few cumulus clouds in the afternoon.
Sunday
Night
Mostly clear becoming mostly to partly clear after midnight. Moderate ridgeline winds decreasing after midnight.
Monday
Mostly sunny with a few cumulus clouds in the afternoon.
Sunday
Night
Mostly clear becoming mostly to partly clear after midnight. Moderate ridgeline winds decreasing after midnight.
Monday
Mostly sunny with a few cumulus clouds in the afternoon.
Sunday
Night
Mostly clear becoming mostly to partly clear in the evening. Moderate to strong ridgeline winds decreasing after midnight.
Monday
Mostly sunny with a few cumulus clouds in the afternoon.
Sunday
Night
Mostly clear becoming mostly to partly clear after midnight. Moderate to strong ridgeline winds decreasing late.
Monday
Mostly sunny with a few cumulus clouds in the afternoon.
Sunday
Night
Mostly clear becoming mostly to partly clear after midnight. Moderate to strong ridgeline winds decreasing late.
Monday
Mostly sunny with a few cumulus clouds in the afternoon.
Sunday
Night
Mostly clear. Moderate to strong ridgeline winds. Moderate to strong ridgeline winds decreasing late.
Monday
Mostly sunny in the morning becoming partly sunny late in the afternoon.
Issued: 2:29 PM PDT Sunday, April 18, 2021
Precipitation (in)
Sunday Night
Monday
Monday Night
Tuesday
5 pm - 5 am
5 am - 5 pm
5 pm - 5 am
5 am - 5 pm
Hurricane Ridge
0
0
0
0
Mt Baker Ski Area
0
0
0
0
Mt. Loop - Barlow Pass
0
0
0
0
Stevens Pass
0
0
0
0
Snoqualmie Pass
0
0
0
0
Crystal Mt
0
0
0
0
Paradise
0
0
0
0
White Pass
0
0
0
0
Washington Pass
0
0
0
0
Mission Ridge
0
0
0
0
Salmon la Sac - Gallagher Head
0
0
0
0
Tieton River - Darland Mt.
0
0
0
0
Mt Hood Meadows
0
0
0
0
Timberline
0
0
0
0
Hurricane Ridge
Precipitation (in)
Sunday Night
0
Monday
0
Monday Night
0
Tuesday
0
Mt Baker Ski Area
Precipitation (in)
Sunday Night
0
Monday
0
Monday Night
0
Tuesday
0
Mt. Loop - Barlow Pass
Precipitation (in)
Sunday Night
0
Monday
0
Monday Night
0
Tuesday
0
Stevens Pass
Precipitation (in)
Sunday Night
0
Monday
0
Monday Night
0
Tuesday
0
Snoqualmie Pass
Precipitation (in)
Sunday Night
0
Monday
0
Monday Night
0
Tuesday
0
Crystal Mt
Precipitation (in)
Sunday Night
0
Monday
0
Monday Night
0
Tuesday
0
Paradise
Precipitation (in)
Sunday Night
0
Monday
0
Monday Night
0
Tuesday
0
White Pass
Precipitation (in)
Sunday Night
0
Monday
0
Monday Night
0
Tuesday
0
Washington Pass
Precipitation (in)
Sunday Night
0
Monday
0
Monday Night
0
Tuesday
0
Mission Ridge
Precipitation (in)
Sunday Night
0
Monday
0
Monday Night
0
Tuesday
0
Salmon la Sac - Gallagher Head
Precipitation (in)
Sunday Night
0
Monday
0
Monday Night
0
Tuesday
0
Tieton River - Darland Mt.
Precipitation (in)
Sunday Night
0
Monday
0
Monday Night
0
Tuesday
0
Mt Hood Meadows
Precipitation (in)
Sunday Night
0
Monday
0
Monday Night
0
Tuesday
0
Timberline
Precipitation (in)
Sunday Night
0
Monday
0
Monday Night
0
Tuesday
0
Issued: 2:29 PM PDT Sunday, April 18, 2021
Snow Level (ft)
Sunday
Evening
Sunday
Night
Monday
Morning
Monday
Afternoon
Monday
Evening
Monday
Night
Tuesday
Morning
Tuesday
Afternoon
Olympics
9000'
8000'
7500'
7500'
7500'
7000'
7500'
7500'
West North
8500'
7000'
7000'
7500'
7500'
7000'
7500'
7500'
West Central
8500'
7500'
6500'
7500'
7500'
7000'
7500'
7500'
West South
9000'
8000'
7500'
7500'
7500'
7000'
7500'
7500'
Stevens Pass
8500'
7000'
6000'
7500'
7500'
7000'
7500'
7500'
Snoqualmie Pass
8500'
7500'
6500'
7500'
7500'
7000'
7500'
7500'
East North
8000'
5500'
5500'
7500'
7500'
7000'
7500'
7500'
East Central
8500'
6000'
5000'
7500'
7500'
7000'
7500'
7500'
East South
9500'
7000'
5000'
7500'
7500'
7000'
7500'
7500'
Mt. Hood
12000'
9000'
5500'
7500'
7500'
7000'
7500'
7500'
Olympics
Elevation
Sunday
Evening
9000'
Sunday
Night
8000'
Monday
Morning
7500'
Monday
Afternoon
7500'
Monday
Evening
7500'
Monday
Night
7000'
Tuesday
Morning
7500'
Tuesday
Afternoon
7500'
West North
Elevation
Sunday
Evening
8500'
Sunday
Night
7000'
Monday
Morning
7000'
Monday
Afternoon
7500'
Monday
Evening
7500'
Monday
Night
7000'
Tuesday
Morning
7500'
Tuesday
Afternoon
7500'
West Central
Elevation
Sunday
Evening
8500'
Sunday
Night
7500'
Monday
Morning
6500'
Monday
Afternoon
7500'
Monday
Evening
7500'
Monday
Night
7000'
Tuesday
Morning
7500'
Tuesday
Afternoon
7500'
West South
Elevation
Sunday
Evening
9000'
Sunday
Night
8000'
Monday
Morning
7500'
Monday
Afternoon
7500'
Monday
Evening
7500'
Monday
Night
7000'
Tuesday
Morning
7500'
Tuesday
Afternoon
7500'
Stevens Pass
Elevation
Sunday
Evening
8500'
Sunday
Night
7000'
Monday
Morning
6000'
Monday
Afternoon
7500'
Monday
Evening
7500'
Monday
Night
7000'
Tuesday
Morning
7500'
Tuesday
Afternoon
7500'
Snoqualmie Pass
Elevation
Sunday
Evening
8500'
Sunday
Night
7500'
Monday
Morning
6500'
Monday
Afternoon
7500'
Monday
Evening
7500'
Monday
Night
7000'
Tuesday
Morning
7500'
Tuesday
Afternoon
7500'
East North
Elevation
Sunday
Evening
8000'
Sunday
Night
5500'
Monday
Morning
5500'
Monday
Afternoon
7500'
Monday
Evening
7500'
Monday
Night
7000'
Tuesday
Morning
7500'
Tuesday
Afternoon
7500'
East Central
Elevation
Sunday
Evening
8500'
Sunday
Night
6000'
Monday
Morning
5000'
Monday
Afternoon
7500'
Monday
Evening
7500'
Monday
Night
7000'
Tuesday
Morning
7500'
Tuesday
Afternoon
7500'
East South
Elevation
Sunday
Evening
9500'
Sunday
Night
7000'
Monday
Morning
5000'
Monday
Afternoon
7500'
Monday
Evening
7500'
Monday
Night
7000'
Tuesday
Morning
7500'
Tuesday
Afternoon
7500'
Mt. Hood
Elevation
Sunday
Evening
12000'
Sunday
Night
9000'
Monday
Morning
5500'
Monday
Afternoon
7500'
Monday
Evening
7500'
Monday
Night
7000'
Tuesday
Morning
7500'
Tuesday
Afternoon
7500'
Issued: 2:29 PM PDT Sunday, April 18, 2021
5000' Temperatures (°F)
Sunday
Night
Monday
Max / Min
Max / Min
Olympics
48 / 35
47 / 42
West North
42 / 34
49 / 39
West Central
44 / 34
49 / 39
West South
49 / 35
50 / 40
Stevens Pass
49 / 34
48 / 37
Snoqualmie Pass
47 / 34
47 / 38
East North
44 / 30
49 / 32
East Central
47 / 32
48 / 34
East South
48 / 32
48 / 35
Mt. Hood
49 / 35
44 / 39
Olympics
5000' Temperature Forecast (Max / Min)
Sunday
Night
48 / 35
Monday
47 / 42
West North
5000' Temperature Forecast (Max / Min)
Sunday
Night
42 / 34
Monday
49 / 39
West Central
5000' Temperature Forecast (Max / Min)
Sunday
Night
44 / 34
Monday
49 / 39
West South
5000' Temperature Forecast (Max / Min)
Sunday
Night
49 / 35
Monday
50 / 40
Stevens Pass
5000' Temperature Forecast (Max / Min)
Sunday
Night
49 / 34
Monday
48 / 37
Snoqualmie Pass
5000' Temperature Forecast (Max / Min)
Sunday
Night
47 / 34
Monday
47 / 38
East North
5000' Temperature Forecast (Max / Min)
Sunday
Night
44 / 30
Monday
49 / 32
East Central
5000' Temperature Forecast (Max / Min)
Sunday
Night
47 / 32
Monday
48 / 34
East South
5000' Temperature Forecast (Max / Min)
Sunday
Night
48 / 32
Monday
48 / 35
Mt. Hood
5000' Temperature Forecast (Max / Min)
Sunday
Night
49 / 35
Monday
44 / 39
Issued: 2:29 PM PDT Sunday, April 18, 2021
Ridgeline Winds (mph)
Sunday
Evening
Sunday
Night
Monday
Morning
Monday
Afternoon
Olympics
NW 0-10
VAR 0-10
VAR 0-10
VAR 0-10
West North
NW 5-15
NE 0-10
VAR 0-10
VAR 0-10
West Central
NW 10-20
NE 0-10
VAR 0-10
VAR 0-10
West South
NW 10-20
NE 0-10
E 5-15
VAR 0-10
Stevens Pass
NW 15-25
NE 15-25
E 5-15
VAR 0-10
Snoqualmie Pass
NW 15-25
NE 5-15
E 5-15
VAR 0-10
East North
NW 20-30
N 10-20
N 5-15
N 5-15
East Central
NW 20-30
N 10-20
NE 5-15
N 5-15
East South
WNW 15-25
N 5-15
NE 5-15
NE 5-15
Mt. Hood
NW 20-30
N 10-20
NE 10-20
ENE 5-15
Olympics
Ridgeline Winds (mph)
Sunday
Evening
NW
0-10
Sunday
Night
VAR
0-10
Monday
Morning
VAR
0-10
Monday
Afternoon
VAR
0-10
West North
Ridgeline Winds (mph)
Sunday
Evening
NW
5-15
Sunday
Night
NE
0-10
Monday
Morning
VAR
0-10
Monday
Afternoon
VAR
0-10
West Central
Ridgeline Winds (mph)
Sunday
Evening
NW
10-20
Sunday
Night
NE
0-10
Monday
Morning
VAR
0-10
Monday
Afternoon
VAR
0-10
West South
Ridgeline Winds (mph)
Sunday
Evening
NW
10-20
Sunday
Night
NE
0-10
Monday
Morning
E
5-15
Monday
Afternoon
VAR
0-10
Stevens Pass
Ridgeline Winds (mph)
Sunday
Evening
NW
15-25
Sunday
Night
NE
15-25
Monday
Morning
E
5-15
Monday
Afternoon
VAR
0-10
Snoqualmie Pass
Ridgeline Winds (mph)
Sunday
Evening
NW
15-25
Sunday
Night
NE
5-15
Monday
Morning
E
5-15
Monday
Afternoon
VAR
0-10
East North
Ridgeline Winds (mph)
Sunday
Evening
NW
20-30
Sunday
Night
N
10-20
Monday
Morning
N
5-15
Monday
Afternoon
N
5-15
East Central
Ridgeline Winds (mph)
Sunday
Evening
NW
20-30
Sunday
Night
N
10-20
Monday
Morning
NE
5-15
Monday
Afternoon
N
5-15
East South
Ridgeline Winds (mph)
Sunday
Evening
WNW
15-25
Sunday
Night
N
5-15
Monday
Morning
NE
5-15
Monday
Afternoon
NE
5-15
Mt. Hood
Ridgeline Winds (mph)
Sunday
Evening
NW
20-30
Sunday
Night
N
10-20
Monday
Morning
NE
10-20
Monday
Afternoon
ENE
5-15
Issued: 2:29 PM PDT Sunday, April 18, 2021
Extended Weather Synopsis
A very similar pattern will continue in the extended with the potential for a slow warming trend for the latter half of the workweek. The forecast will remain mostly dry with partly to mostly clear conditions. Unsettled weather may return next weekend.
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).