A trough passing over the Pacific Northwest should maintain scattered snow showers in the mountains overnight and into Saturday. While accumulations appear light, some trailheads could receive a few inches of snow, especially near a weak Puget Sound Convergence Zone focused between the Mountain Loop and Hwy 2 areas. Look for ridgetop winds to begin to increase throughout the short-term forecast as the trough exists and the jet stream passes over the region. On Saturday expect partly to mostly cloudy skies, brief sun breaks, and occasional snow showers for most of our mountain areas.
The weather really begins to change Saturday night into Sunday as warming temperatures, moderate to heavy precipitation, and very strong winds impact the entire forecast area. An atmospheric river event tied to a strong jet stream will take aim at the British Columbia coast late Saturday. As it does, you may notice the snowline slowly creeping up the mountainside overnight. A large pulse of warmer air appears to quickly swing into the area Sunday morning with a rapid rise in temperatures and brings rain above pass levels. Temperatures should continue to warm with snow levels peaking sometime Sunday night or Monday. As the jet stream begins to sag south, precipitation in the Olympics and Cascades will dramatically increase. Expect periods of heavy rain and snow in most mountain locations accompanied by strong ridgetop winds. The atmospheric river takes aim at Washington as we head into the extended forecast period.
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
Friday
Night
Mostly cloudy with isolated snow showers.
Saturday
Partly to mostly cloudy. Isolated flurries possible.
Friday
Night
Cloudy with scattered snow showers. W winds increasing.
Saturday
Mostly cloudy with isolated snow showers. W winds increasing in the afternoon.
Friday
Night
Cloudy with scattered showers. Weak convergence zone possible near Hwy 2. W winds increasing.
Saturday
Mostly cloudy with isolated snow showers.
Friday
Night
Mostly cloudy to cloudy. Isolated snowers. W winds increasing.
Saturday
Partly to mostly cloudy. Isolated snow showers. W winds becoming strong
Friday
Night
Cloudy with a weak convergence zone possible. W winds increasing.
Saturday
Mostly cloudy with some sun breaks. Scattered showers. W winds becoming strong.
Friday
Night
Mostly cloudy with scattered showers. W winds becoming strong.
Saturday
Mostly cloudy with a few sun breaks possible. Scattered showers. Strong W winds.
Friday
Night
Mostly cloudy with isolated showers.
Saturday
Partly to mostly cloudy with isolated showers. WNW winds increasing.
Friday
Night
Partly to mostly cloudy. Isolated showers near the crest. W winds becoming strong.
Saturday
Partly to mostly cloudy. Isolated showers near the crest. Strong W winds.
Friday
Night
Partly to mostly cloudy. Isolated showers near the crest. W winds increasing.
Saturday
Partly to mostly cloudy. Isolated showers near the crest. Moderate to strong W winds.
Friday
Night
Mostly cloudy with scattered snow showers.
Saturday
Mostly cloudy with sun breaks possible. Scattered shower. W winds becoming strong.
Issued: 1:59 PM PST Friday, February 19, 2021
Precipitation (in)
Friday Night
Saturday
Saturday Night
Sunday
4 pm - 4 am
4 am - 4 pm
4 pm - 4 am
4 am - 4 pm
Hurricane Ridge
LT 0.10
0
LT 0.25
0.25 - 0.50
Mt Baker Ski Area
0.25
LT 0.25
0.25 - 0.50
1.00
Mt. Loop - Barlow Pass
0.25 - 0.50
0.25
0.50 - 0.75
1.00
Stevens Pass
0.25
0.25
0.25 - 0.50
0.75
Snoqualmie Pass
0.25
0.25
0.50
0.75
Crystal Mt
LT 0.10
LT 0.10
LT 0.25
0.25
Paradise
0.25
LT 0.25
0.50 - 0.75
0.75 -1.00
White Pass
LT 0.25
LT 0.25
0.25 - 0.50
0.50 - 0.75
Washington Pass
LT 0.10
LT 0.10
LT 0.25
0.25 - 0.50
Mission Ridge
0
0
LT 0.10
0.25
Salmon la Sac - Gallagher Head
LT 0.25
LT 0.25
0.25 - 0.50
0.50
Tieton River - Darland Mt.
LT 0.10
LT 0.10
LT 0.25
0.25 - 0.50
Mt Hood Meadows
0.25
0.25
0.25 - 0.50
0.50 - 0.75
Timberline
0.25
0.25
0.50
0.75
Hurricane Ridge
Precipitation (in)
Friday Night
LT 0.10
Saturday
0
Saturday Night
LT 0.25
Sunday
0.25 - 0.50
Mt Baker Ski Area
Precipitation (in)
Friday Night
0.25
Saturday
LT 0.25
Saturday Night
0.25 - 0.50
Sunday
1.00
Mt. Loop - Barlow Pass
Precipitation (in)
Friday Night
0.25 - 0.50
Saturday
0.25
Saturday Night
0.50 - 0.75
Sunday
1.00
Stevens Pass
Precipitation (in)
Friday Night
0.25
Saturday
0.25
Saturday Night
0.25 - 0.50
Sunday
0.75
Snoqualmie Pass
Precipitation (in)
Friday Night
0.25
Saturday
0.25
Saturday Night
0.50
Sunday
0.75
Crystal Mt
Precipitation (in)
Friday Night
LT 0.10
Saturday
LT 0.10
Saturday Night
LT 0.25
Sunday
0.25
Paradise
Precipitation (in)
Friday Night
0.25
Saturday
LT 0.25
Saturday Night
0.50 - 0.75
Sunday
0.75 -1.00
White Pass
Precipitation (in)
Friday Night
LT 0.25
Saturday
LT 0.25
Saturday Night
0.25 - 0.50
Sunday
0.50 - 0.75
Washington Pass
Precipitation (in)
Friday Night
LT 0.10
Saturday
LT 0.10
Saturday Night
LT 0.25
Sunday
0.25 - 0.50
Mission Ridge
Precipitation (in)
Friday Night
0
Saturday
0
Saturday Night
LT 0.10
Sunday
0.25
Salmon la Sac - Gallagher Head
Precipitation (in)
Friday Night
LT 0.25
Saturday
LT 0.25
Saturday Night
0.25 - 0.50
Sunday
0.50
Tieton River - Darland Mt.
Precipitation (in)
Friday Night
LT 0.10
Saturday
LT 0.10
Saturday Night
LT 0.25
Sunday
0.25 - 0.50
Mt Hood Meadows
Precipitation (in)
Friday Night
0.25
Saturday
0.25
Saturday Night
0.25 - 0.50
Sunday
0.50 - 0.75
Timberline
Precipitation (in)
Friday Night
0.25
Saturday
0.25
Saturday Night
0.50
Sunday
0.75
Issued: 1:59 PM PST Friday, February 19, 2021
Snow Level (ft)
Friday
Evening
Friday
Night
Saturday
Morning
Saturday
Afternoon
Saturday
Evening
Saturday
Night
Sunday
Morning
Sunday
Afternoon
Olympics
2500'
2000'
2000'
2500'
2000'
3000'
4500'
5000'
West North
1500'
1500'
1500'
2000'
1500'
2000'
3000'
4000'
West Central
2000'
2000'
2000'
2500'
2000'
2500'
3500'
4500'
West South
2500'
2000'
2000'
2500'
2000'
3000'
4000'
5000'
Stevens Pass
2000'
2000'
1500'
2500'
2000'
2500'
3500'
4500'
Snoqualmie Pass
2500'
2000'
2000'
2500'
2000'
2500'
4000'
5000'
East North
1000'
1000'
1000'
2000'
1000'
1500'
2500'
3500'
East Central
1500'
1000'
1500'
2500'
1500'
2000'
3000'
4500'
East South
2000'
1000'
1500'
2500'
2000'
2000'
3500'
4500'
Mt. Hood
2500'
2000'
2000'
2500'
2500'
2500'
3500'
5000'
Olympics
Elevation
Friday
Evening
2500'
Friday
Night
2000'
Saturday
Morning
2000'
Saturday
Afternoon
2500'
Saturday
Evening
2000'
Saturday
Night
3000'
Sunday
Morning
4500'
Sunday
Afternoon
5000'
West North
Elevation
Friday
Evening
1500'
Friday
Night
1500'
Saturday
Morning
1500'
Saturday
Afternoon
2000'
Saturday
Evening
1500'
Saturday
Night
2000'
Sunday
Morning
3000'
Sunday
Afternoon
4000'
West Central
Elevation
Friday
Evening
2000'
Friday
Night
2000'
Saturday
Morning
2000'
Saturday
Afternoon
2500'
Saturday
Evening
2000'
Saturday
Night
2500'
Sunday
Morning
3500'
Sunday
Afternoon
4500'
West South
Elevation
Friday
Evening
2500'
Friday
Night
2000'
Saturday
Morning
2000'
Saturday
Afternoon
2500'
Saturday
Evening
2000'
Saturday
Night
3000'
Sunday
Morning
4000'
Sunday
Afternoon
5000'
Stevens Pass
Elevation
Friday
Evening
2000'
Friday
Night
2000'
Saturday
Morning
1500'
Saturday
Afternoon
2500'
Saturday
Evening
2000'
Saturday
Night
2500'
Sunday
Morning
3500'
Sunday
Afternoon
4500'
Snoqualmie Pass
Elevation
Friday
Evening
2500'
Friday
Night
2000'
Saturday
Morning
2000'
Saturday
Afternoon
2500'
Saturday
Evening
2000'
Saturday
Night
2500'
Sunday
Morning
4000'
Sunday
Afternoon
5000'
East North
Elevation
Friday
Evening
1000'
Friday
Night
1000'
Saturday
Morning
1000'
Saturday
Afternoon
2000'
Saturday
Evening
1000'
Saturday
Night
1500'
Sunday
Morning
2500'
Sunday
Afternoon
3500'
East Central
Elevation
Friday
Evening
1500'
Friday
Night
1000'
Saturday
Morning
1500'
Saturday
Afternoon
2500'
Saturday
Evening
1500'
Saturday
Night
2000'
Sunday
Morning
3000'
Sunday
Afternoon
4500'
East South
Elevation
Friday
Evening
2000'
Friday
Night
1000'
Saturday
Morning
1500'
Saturday
Afternoon
2500'
Saturday
Evening
2000'
Saturday
Night
2000'
Sunday
Morning
3500'
Sunday
Afternoon
4500'
Mt. Hood
Elevation
Friday
Evening
2500'
Friday
Night
2000'
Saturday
Morning
2000'
Saturday
Afternoon
2500'
Saturday
Evening
2500'
Saturday
Night
2500'
Sunday
Morning
3500'
Sunday
Afternoon
5000'
Issued: 1:59 PM PST Friday, February 19, 2021
5000' Temperatures (°F)
Friday
Night
Saturday
Max / Min
Max / Min
Olympics
22 / 16
24 / 17
West North
21 / 17
22 / 17
West Central
22 / 19
22 / 19
West South
24 / 19
25 / 18
Stevens Pass
22 / 20
23 / 20
Snoqualmie Pass
22 / 20
23 / 19
East North
20 / 16
25 / 16
East Central
22 / 18
24 / 18
East South
23 / 18
26 / 17
Mt. Hood
25 / 19
25 / 20
Olympics
5000' Temperature Forecast (Max / Min)
Friday
Night
22 / 16
Saturday
24 / 17
West North
5000' Temperature Forecast (Max / Min)
Friday
Night
21 / 17
Saturday
22 / 17
West Central
5000' Temperature Forecast (Max / Min)
Friday
Night
22 / 19
Saturday
22 / 19
West South
5000' Temperature Forecast (Max / Min)
Friday
Night
24 / 19
Saturday
25 / 18
Stevens Pass
5000' Temperature Forecast (Max / Min)
Friday
Night
22 / 20
Saturday
23 / 20
Snoqualmie Pass
5000' Temperature Forecast (Max / Min)
Friday
Night
22 / 20
Saturday
23 / 19
East North
5000' Temperature Forecast (Max / Min)
Friday
Night
20 / 16
Saturday
25 / 16
East Central
5000' Temperature Forecast (Max / Min)
Friday
Night
22 / 18
Saturday
24 / 18
East South
5000' Temperature Forecast (Max / Min)
Friday
Night
23 / 18
Saturday
26 / 17
Mt. Hood
5000' Temperature Forecast (Max / Min)
Friday
Night
25 / 19
Saturday
25 / 20
Issued: 1:59 PM PST Friday, February 19, 2021
Ridgeline Winds (mph)
Friday
Evening
Friday
Night
Saturday
Morning
Saturday
Afternoon
Olympics
WSW 5-15
WNW 15-25
WNW 15-25
W 10-20
West North
SW 10-20
W 15-25
W 10-20
W 15-25
West Central
WSW 10-20
W 15-25
WNW 15-25
WNW 15-25
West South
W 10-20
W 15-25
WNW 15-25
WNW 20-30
Stevens Pass
W 10-20
WNW 15-25
WNW 15-25
W 20-30
Snoqualmie Pass
W 10-20
W 20-30
WNW 20-30
W 20-30
East North
SW 5-15
W 10-20
W 15-25
W 15-25
East Central
WSW 15-25
W 20-30
WNW 25-35
WNW 25-35
East South
W 10-20
WNW 15-25
WNW 20-30
WNW 20-30
Mt. Hood
W 15-25
WNW 15-25
WNW 20-30
WNW 25-35
Olympics
Ridgeline Winds (mph)
Friday
Evening
WSW
5-15
Friday
Night
WNW
15-25
Saturday
Morning
WNW
15-25
Saturday
Afternoon
W
10-20
West North
Ridgeline Winds (mph)
Friday
Evening
SW
10-20
Friday
Night
W
15-25
Saturday
Morning
W
10-20
Saturday
Afternoon
W
15-25
West Central
Ridgeline Winds (mph)
Friday
Evening
WSW
10-20
Friday
Night
W
15-25
Saturday
Morning
WNW
15-25
Saturday
Afternoon
WNW
15-25
West South
Ridgeline Winds (mph)
Friday
Evening
W
10-20
Friday
Night
W
15-25
Saturday
Morning
WNW
15-25
Saturday
Afternoon
WNW
20-30
Stevens Pass
Ridgeline Winds (mph)
Friday
Evening
W
10-20
Friday
Night
WNW
15-25
Saturday
Morning
WNW
15-25
Saturday
Afternoon
W
20-30
Snoqualmie Pass
Ridgeline Winds (mph)
Friday
Evening
W
10-20
Friday
Night
W
20-30
Saturday
Morning
WNW
20-30
Saturday
Afternoon
W
20-30
East North
Ridgeline Winds (mph)
Friday
Evening
SW
5-15
Friday
Night
W
10-20
Saturday
Morning
W
15-25
Saturday
Afternoon
W
15-25
East Central
Ridgeline Winds (mph)
Friday
Evening
WSW
15-25
Friday
Night
W
20-30
Saturday
Morning
WNW
25-35
Saturday
Afternoon
WNW
25-35
East South
Ridgeline Winds (mph)
Friday
Evening
W
10-20
Friday
Night
WNW
15-25
Saturday
Morning
WNW
20-30
Saturday
Afternoon
WNW
20-30
Mt. Hood
Ridgeline Winds (mph)
Friday
Evening
W
15-25
Friday
Night
WNW
15-25
Saturday
Morning
WNW
20-30
Saturday
Afternoon
WNW
25-35
Issued: 1:59 PM PST Friday, February 19, 2021
Extended Weather Synopsis
The brunt of this atmospheric river event appears to occur Sunday night into Monday morning as a strong jet stream and deep sub-tropical moisture tap bare down on the Pacific Northwest. Snow levels should peak early Monday between 4500 and 6000ft. Many of our mountain locations could receive several inches of total precipitation before this event winds down. A building high-pressure ridge in the eastern Pacific eventually breaks the flow of moisture into the atmospheric river Monday night and turns our prevailing winds northwesterly. This should quickly usher in much colder air, drop snow levels, and returning snow to all trailhead locations.
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).