The closed low impacting the region with some light snow on Wednesday afternoon moves onshore around the Columbia River mouth Wednesday evening. Light snow becomes increasingly patchy and decreases overnight from a northern extent around highway 2, southward.
The region mostly dries out late Wednesday night and early Thursday morning before a shortwave trough moving down from British Columbia taps into just enough coastal moisture for some light snow showers and weak convergence activity focused towards the central Washington Cascades.
Wednesday night through Thursday, our mountains should expect 1-3" of snow accumulation with up to 6" in the Mt. Hood area.
Snow shower activity tapers to flurries Thursday night as a weak ridge centered off the coast edges into the area. The ridge should bring fair weather on Friday with filtered sunshine in the morning and thickening high clouds in the afternoon.
Temperatures remain cold and relatively steady throughout the forecast period, with highs in the 20s and lows dropping into the 10s in many locations.
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
Wednesday
Night
Snow flurries possible during the evening hours, then partial clearing overnight.
Thursday
A chance of light snow showers in the morning. Then, decreasing clouds and partly sunny conditions in the afternoon.
Wednesday
Night
Mostly cloudy in the evening with light snow possible overnight. Cold.
Thursday
Light snow showers.
Wednesday
Night
Mostly cloudy in the evening with light snow possible overnight. Cold.
Thursday
Light snow showers.
Wednesday
Night
Cloudy. Cold. Strong ridgeline winds the Crystal area becoming moderate and decreasing.
Thursday
Cloudy with light snow showers developing in the afternoon.
Wednesday
Night
Light snow is possible at times. Light to moderate E winds become light at the Pass.
Thursday
Increasing light snow showers. Light E wind shifting W early and increasing.
Wednesday
Night
Light snow at times. Moderate E winds become light at the Pass.
Thursday
Increasing light snow showers. Light E wind shifting W early and increasing.
Wednesday
Night
Mostly cloudy.
Thursday
Mostly cloudy with a chance of snow flurries.
Wednesday
Night
Light snow tapering during the evening, then becoming cloudy with flurries.
Thursday
Mostly cloudy with an increasing chance of light snow showers in the afternoon.
Wednesday
Night
Light snow tapering during the evening, then becoming cloudy with flurries.
Thursday
Partly cloudy with an increasing chance of light snow showers near the Cascade Crest in the afternoon.
Wednesday
Night
Light to occasionally moderate snow.
Thursday
Light snow showers.
Issued: 2:05 PM PST Wednesday, December 15, 2021
Precipitation (in)
Wednesday Night
Thursday
Thursday Night
Friday
4 pm - 4 am
4 am - 4 pm
4 pm - 4 am
4 am - 4 pm
Hurricane Ridge
0
LT 0.10
0
0
Mt Baker Ski Area
0
LT 0.10
0
0
Mt. Loop - Barlow Pass
0
LT 0.25
0
0
Stevens Pass
LT 0.10
LT 0.25
0
0
Snoqualmie Pass
LT 0.10
LT 0.25
LT 0.10
0
Crystal Mt
LT 0.10
LT 0.10
LT 0.10
0
Paradise
LT 0.25
LT 0.10
LT 0.10
0
White Pass
LT 0.10
LT 0.10
LT 0.10
0
Washington Pass
0
LT 0.10
0
0
Mission Ridge
LT 0.10
0
0
0
Salmon la Sac - Gallagher Head
LT 0.10
LT 0.10
0
0
Tieton River - Darland Mt.
LT 0.10
0
0
0
Mt Hood Meadows
0.25
LT 0.10
LT 0.10
0
Timberline
0.25
LT 0.10
LT 0.10
0
Hurricane Ridge
Precipitation (in)
Wednesday Night
0
Thursday
LT 0.10
Thursday Night
0
Friday
0
Mt Baker Ski Area
Precipitation (in)
Wednesday Night
0
Thursday
LT 0.10
Thursday Night
0
Friday
0
Mt. Loop - Barlow Pass
Precipitation (in)
Wednesday Night
0
Thursday
LT 0.25
Thursday Night
0
Friday
0
Stevens Pass
Precipitation (in)
Wednesday Night
LT 0.10
Thursday
LT 0.25
Thursday Night
0
Friday
0
Snoqualmie Pass
Precipitation (in)
Wednesday Night
LT 0.10
Thursday
LT 0.25
Thursday Night
LT 0.10
Friday
0
Crystal Mt
Precipitation (in)
Wednesday Night
LT 0.10
Thursday
LT 0.10
Thursday Night
LT 0.10
Friday
0
Paradise
Precipitation (in)
Wednesday Night
LT 0.25
Thursday
LT 0.10
Thursday Night
LT 0.10
Friday
0
White Pass
Precipitation (in)
Wednesday Night
LT 0.10
Thursday
LT 0.10
Thursday Night
LT 0.10
Friday
0
Washington Pass
Precipitation (in)
Wednesday Night
0
Thursday
LT 0.10
Thursday Night
0
Friday
0
Mission Ridge
Precipitation (in)
Wednesday Night
LT 0.10
Thursday
0
Thursday Night
0
Friday
0
Salmon la Sac - Gallagher Head
Precipitation (in)
Wednesday Night
LT 0.10
Thursday
LT 0.10
Thursday Night
0
Friday
0
Tieton River - Darland Mt.
Precipitation (in)
Wednesday Night
LT 0.10
Thursday
0
Thursday Night
0
Friday
0
Mt Hood Meadows
Precipitation (in)
Wednesday Night
0.25
Thursday
LT 0.10
Thursday Night
LT 0.10
Friday
0
Timberline
Precipitation (in)
Wednesday Night
0.25
Thursday
LT 0.10
Thursday Night
LT 0.10
Friday
0
Issued: 2:05 PM PST Wednesday, December 15, 2021
Snow Level (ft)
Wednesday
Evening*
Wednesday
Night*
Thursday
Morning
Thursday
Afternoon
Thursday
Evening*
Thursday
Night*
Friday
Morning*
Friday
Afternoon*
Olympics
2500'
1500'
500'
2000'
2000'
1500'
500'
2500'
West North
1500'
1000'
500'
1000'
1000'
1000'
1000'
2000'
West Central
1500'
500'
500'
1500'
1000'
1000'
1000'
2500'
West South
500'
500'
500'
2000'
1500'
500'
1000'
3000'
Stevens Pass
0
0
0
1500'
1000'
500'
0
2500'
Snoqualmie Pass
0
0
0
1500'
1000'
500'
500'
2500'
East North
500'
0
0
1000'
1000'
500'
0
1500'
East Central
0
0
0
1500'
1000'
1000'
500'
2500'
East South
500'
0
500'
2000'
1500'
1000'
1500'
3000'
Mt. Hood
1500'
1000'
1500'
2500'
2000'
1500'
2000'
3500'
Olympics
Elevation
Wednesday
Evening*
2500'
Wednesday
Night*
1500'
Thursday
Morning
500'
Thursday
Afternoon
2000'
Thursday
Evening*
2000'
Thursday
Night*
1500'
Friday
Morning*
500'
Friday
Afternoon*
2500'
West North
Elevation
Wednesday
Evening*
1500'
Wednesday
Night*
1000'
Thursday
Morning
500'
Thursday
Afternoon
1000'
Thursday
Evening*
1000'
Thursday
Night*
1000'
Friday
Morning*
1000'
Friday
Afternoon*
2000'
West Central
Elevation
Wednesday
Evening*
1500'
Wednesday
Night*
500'
Thursday
Morning
500'
Thursday
Afternoon
1500'
Thursday
Evening*
1000'
Thursday
Night*
1000'
Friday
Morning*
1000'
Friday
Afternoon*
2500'
West South
Elevation
Wednesday
Evening*
500'
Wednesday
Night*
500'
Thursday
Morning
500'
Thursday
Afternoon
2000'
Thursday
Evening*
1500'
Thursday
Night*
500'
Friday
Morning*
1000'
Friday
Afternoon*
3000'
Stevens Pass
Elevation
Wednesday
Evening*
0'
Wednesday
Night*
0'
Thursday
Morning
0'
Thursday
Afternoon
1500'
Thursday
Evening*
1000'
Thursday
Night*
500'
Friday
Morning*
0'
Friday
Afternoon*
2500'
Snoqualmie Pass
Elevation
Wednesday
Evening*
0'
Wednesday
Night*
0'
Thursday
Morning
0'
Thursday
Afternoon
1500'
Thursday
Evening*
1000'
Thursday
Night*
500'
Friday
Morning*
500'
Friday
Afternoon*
2500'
East North
Elevation
Wednesday
Evening*
500'
Wednesday
Night*
0'
Thursday
Morning
0'
Thursday
Afternoon
1000'
Thursday
Evening*
1000'
Thursday
Night*
500'
Friday
Morning*
0'
Friday
Afternoon*
1500'
East Central
Elevation
Wednesday
Evening*
0'
Wednesday
Night*
0'
Thursday
Morning
0'
Thursday
Afternoon
1500'
Thursday
Evening*
1000'
Thursday
Night*
1000'
Friday
Morning*
500'
Friday
Afternoon*
2500'
East South
Elevation
Wednesday
Evening*
500'
Wednesday
Night*
0'
Thursday
Morning
500'
Thursday
Afternoon
2000'
Thursday
Evening*
1500'
Thursday
Night*
1000'
Friday
Morning*
1500'
Friday
Afternoon*
3000'
Mt. Hood
Elevation
Wednesday
Evening*
1500'
Wednesday
Night*
1000'
Thursday
Morning
1500'
Thursday
Afternoon
2500'
Thursday
Evening*
2000'
Thursday
Night*
1500'
Friday
Morning*
2000'
Friday
Afternoon*
3500'
Issued: 2:05 PM PST Wednesday, December 15, 2021
5000' Temperatures (°F)
Wednesday
Night
Thursday
Max / Min
Max / Min
Olympics
24 / 19
24 / 18
West North
22 / 18
22 / 17
West Central
19 / 17
23 / 18
West South
21 / 18
24 / 19
Stevens Pass
18 / 13
23 / 18
Snoqualmie Pass
20 / 17
23 / 20
East North
15 / 13
22 / 12
East Central
18 / 13
25 / 15
East South
18 / 14
25 / 17
Mt. Hood
26 / 24
26 / 22
Olympics
5000' Temperature Forecast (Max / Min)
Wednesday
Night
24 / 19
Thursday
24 / 18
West North
5000' Temperature Forecast (Max / Min)
Wednesday
Night
22 / 18
Thursday
22 / 17
West Central
5000' Temperature Forecast (Max / Min)
Wednesday
Night
19 / 17
Thursday
23 / 18
West South
5000' Temperature Forecast (Max / Min)
Wednesday
Night
21 / 18
Thursday
24 / 19
Stevens Pass
5000' Temperature Forecast (Max / Min)
Wednesday
Night
18 / 13
Thursday
23 / 18
Snoqualmie Pass
5000' Temperature Forecast (Max / Min)
Wednesday
Night
20 / 17
Thursday
23 / 20
East North
5000' Temperature Forecast (Max / Min)
Wednesday
Night
15 / 13
Thursday
22 / 12
East Central
5000' Temperature Forecast (Max / Min)
Wednesday
Night
18 / 13
Thursday
25 / 15
East South
5000' Temperature Forecast (Max / Min)
Wednesday
Night
18 / 14
Thursday
25 / 17
Mt. Hood
5000' Temperature Forecast (Max / Min)
Wednesday
Night
26 / 24
Thursday
26 / 22
Issued: 2:05 PM PST Wednesday, December 15, 2021
Ridgeline Winds (mph)
Wednesday
Evening
Wednesday
Night
Thursday
Morning
Thursday
Afternoon
Olympics
S 5-15
SSE 0-10
WNW 0-10
WNW 5-15
West North
SSE 5-15
SSW 0-10
W 0-10
NW 5-15
West Central
ESE 15-25
SSE 5-15
W 5-15
WNW 10-20
West South
SE 15-25
SW 0-10
W 0-10
W 5-15
Stevens Pass
ESE 10-20
SE 0-10
W 5-15
WNW 10-20
Snoqualmie Pass
ESE 15-25
SE 0-10
W 5-15
WNW 15-25
East North
SE 10-20
S 5-15
W 5-15
WNW 10-20
East Central
SE 15-25
WSW 0-10
WNW 10-20
WNW 15-25
East South
SE 5-15
WSW 0-10
WNW 5-15
WNW 10-20
Mt. Hood
SW 10-20
WSW 10-20
WSW 5-15
W 15-25
Olympics
Ridgeline Winds (mph)
Wednesday
Evening
S
5-15
Wednesday
Night
SSE
0-10
Thursday
Morning
WNW
0-10
Thursday
Afternoon
WNW
5-15
West North
Ridgeline Winds (mph)
Wednesday
Evening
SSE
5-15
Wednesday
Night
SSW
0-10
Thursday
Morning
W
0-10
Thursday
Afternoon
NW
5-15
West Central
Ridgeline Winds (mph)
Wednesday
Evening
ESE
15-25
Wednesday
Night
SSE
5-15
Thursday
Morning
W
5-15
Thursday
Afternoon
WNW
10-20
West South
Ridgeline Winds (mph)
Wednesday
Evening
SE
15-25
Wednesday
Night
SW
0-10
Thursday
Morning
W
0-10
Thursday
Afternoon
W
5-15
Stevens Pass
Ridgeline Winds (mph)
Wednesday
Evening
ESE
10-20
Wednesday
Night
SE
0-10
Thursday
Morning
W
5-15
Thursday
Afternoon
WNW
10-20
Snoqualmie Pass
Ridgeline Winds (mph)
Wednesday
Evening
ESE
15-25
Wednesday
Night
SE
0-10
Thursday
Morning
W
5-15
Thursday
Afternoon
WNW
15-25
East North
Ridgeline Winds (mph)
Wednesday
Evening
SE
10-20
Wednesday
Night
S
5-15
Thursday
Morning
W
5-15
Thursday
Afternoon
WNW
10-20
East Central
Ridgeline Winds (mph)
Wednesday
Evening
SE
15-25
Wednesday
Night
WSW
0-10
Thursday
Morning
WNW
10-20
Thursday
Afternoon
WNW
15-25
East South
Ridgeline Winds (mph)
Wednesday
Evening
SE
5-15
Wednesday
Night
WSW
0-10
Thursday
Morning
WNW
5-15
Thursday
Afternoon
WNW
10-20
Mt. Hood
Ridgeline Winds (mph)
Wednesday
Evening
SW
10-20
Wednesday
Night
WSW
10-20
Thursday
Morning
WSW
5-15
Thursday
Afternoon
W
15-25
Issued: 2:05 PM PST Wednesday, December 15, 2021
Extended Weather Synopsis
A significant storm system begins to impact northern Washington state on Friday night with some light snowfall, but most of the warm frontal precipitation lfits northward into Canada. As the trailing cold front drops ESE, snowfall should pick up, particularly later Friday night. The heaviest rain and snow arrives Saturday night ahead of a strong cold front passing trough the Cascades by Sunday morning. Warming in southern parts of the forecast region should change Crystal and Mt. Hood ski area bases to rain on Saturday, but cold air pooled east of the Cascade Crest likely keeps the central Cascade Passes primarily snow. Some frontal precipitation may continue near Mt. Hood on Sunday as the cold front stalls, but trough moving onshore over Washington State should bring significant cooling and mostly light snow shower activity.
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).