Issued: 6:53 AM PST Friday, March 12, 2021
by Dennis D'Amico

Jump to: Weather Forecast I Precipitation I Snow Level I 5000' Temps I Ridgeline Winds I

Weather Synopsis

Another fine day is on tap across the Pacific Northwest after high clouds draped across the Washington Cascades and Olympics lift north in the afternoon. Overnight temperatures were generally a few degrees warmer this morning than yesterday. That's a trend that should continue today with freezing levels and afternoon temperatures slightly warmer than Thursday. 

An upper level ridge of high pressure centered offshore has flopped over into Pacific Northwest and extends inland. The ridge axis won't shift very much over the next 36 hours.  A frontal boundary and storm track is aimed at central British Columbia.  The orientation of that frontal boundary will change as we head into tomorrow with a trough digging behind the front and re-orienting the boundary in a more south-north fashion. The quasi-stationary upper level low feature that's been with us for most of the week has moved into southern California and won't be a factor in our region today. 

The frontal system should be far enough offshore Saturday to keep the mostly sunny stretch going through the afternoon. Increasing high clouds are possible late in the day for the Olympics. Mild temperatures will continue Friday night and Saturday. Freezing levels will continue their gradual climb, peaking between 7000-9000' on Saturday. 

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 Mostly cloudy with filtered sunshine and high clouds in the morning becoming partly to mostly sunny in the afternoon.
Friday Night Partly cloudy in the evening then mostly clear.
Friday Mostly cloudy with filtered sunshine and high clouds in the morning becoming partly to mostly sunny in the afternoon.
Friday Night Mostly clear.
Friday Mostly cloudy with filtered sunshine and high clouds in the morning becoming mostly sunny in the afternoon.
Friday Night Mostly clear.
Friday Partly cloudy with periods of filtered sunshine and high clouds in the morning becoming mostly sunny in the afternoon.
Friday Night Mostly clear.
Friday Partly cloudy with periods of filtered sunshine and high clouds in the morning becoming mostly sunny in the afternoon. Light west winds at Pass level becoming moderate in the afternoon.
Friday Night Mostly clear. Light west winds at Pass level becoming light after midnight.
Friday Partly cloudy with periods of filtered sunshine and high clouds in the morning becoming mostly sunny in the afternoon. Light west winds at Pass level becoming moderate in the afternoon.
Friday Night Mostly clear. Light west winds at Pass level becoming light after midnight.
Friday Mostly cloudy with filtered sunshine and high clouds in the morning becoming mostly sunny in the afternoon.
Friday Night Mostly clear.
Friday Partly cloudy with periods of filtered sunshine and high clouds in the morning becoming mostly sunny in the afternoon.
Friday Night Mostly clear.
Friday A few high clouds in the morning, otherwise mostly sunny.
Friday Night Mostly clear.
Friday A few high clouds in the morning, otherwise mostly sunny.
Friday Night Mostly clear.

Precipitation (in)

Friday Friday Night Saturday
4 am - 4 pm 4 pm - 4 am 4 am - 4 pm
Hurricane Ridge 0 0 0
Mt Baker Ski Area 0 0 0
Mt. Loop - Barlow Pass 0 0 0
Stevens Pass 0 0 0
Snoqualmie Pass 0 0 0
Crystal Mt 0 0 0
Paradise 0 0 0
White Pass 0 0 0
Washington Pass 0 0 0
Mission Ridge 0 0 0
Salmon la Sac - Gallagher Head 0 0 0
Tieton River - Darland Mt. 0 0 0
Mt Hood Meadows 0 0 0
Timberline 0 0 0
Hurricane Ridge Precipitation (in)
Friday 0
Friday Night 0
Saturday 0
Mt Baker Ski Area Precipitation (in)
Friday 0
Friday Night 0
Saturday 0
Mt. Loop - Barlow Pass Precipitation (in)
Friday 0
Friday Night 0
Saturday 0
Stevens Pass Precipitation (in)
Friday 0
Friday Night 0
Saturday 0
Snoqualmie Pass Precipitation (in)
Friday 0
Friday Night 0
Saturday 0
Crystal Mt Precipitation (in)
Friday 0
Friday Night 0
Saturday 0
Paradise Precipitation (in)
Friday 0
Friday Night 0
Saturday 0
White Pass Precipitation (in)
Friday 0
Friday Night 0
Saturday 0
Washington Pass Precipitation (in)
Friday 0
Friday Night 0
Saturday 0
Mission Ridge Precipitation (in)
Friday 0
Friday Night 0
Saturday 0
Salmon la Sac - Gallagher Head Precipitation (in)
Friday 0
Friday Night 0
Saturday 0
Tieton River - Darland Mt. Precipitation (in)
Friday 0
Friday Night 0
Saturday 0
Mt Hood Meadows Precipitation (in)
Friday 0
Friday Night 0
Saturday 0
Timberline Precipitation (in)
Friday 0
Friday Night 0
Saturday 0

Snow Level (ft)

Friday Morning Friday Afternoon Friday Evening Friday Night Saturday Morning Saturday Afternoon
Olympics 4500' 6000' 6500' 6500' 7500' 7500'
West North 3000' 5000' 5000' 5500' 6000' 7000'
West Central 2500' 5500' 5500' 6500' 7500' 7500'
West South 3500' 6000' 6000' 6500' 8000' 8000'
Stevens Pass 3000' 5500' 5500' 6500' 7500' 7500'
Snoqualmie Pass 3500' 5500' 5500' 6500' 7500' 7500'
East North 2500' 5500' 4500' 4000' 5500' 6500'
East Central 3000' 5500' 5500' 6000' 7000' 7500'
East South 3500' 6000' 6000' 6000' 7000' 8000'
Mt. Hood 4000' 6500' 7000' 7500' 8000' 9000'
Olympics Elevation
Friday Morning 4500'
Friday Afternoon 6000'
Friday Evening 6500'
Friday Night 6500'
Saturday Morning 7500'
Saturday Afternoon 7500'
West North Elevation
Friday Morning 3000'
Friday Afternoon 5000'
Friday Evening 5000'
Friday Night 5500'
Saturday Morning 6000'
Saturday Afternoon 7000'
West Central Elevation
Friday Morning 2500'
Friday Afternoon 5500'
Friday Evening 5500'
Friday Night 6500'
Saturday Morning 7500'
Saturday Afternoon 7500'
West South Elevation
Friday Morning 3500'
Friday Afternoon 6000'
Friday Evening 6000'
Friday Night 6500'
Saturday Morning 8000'
Saturday Afternoon 8000'
Stevens Pass Elevation
Friday Morning 3000'
Friday Afternoon 5500'
Friday Evening 5500'
Friday Night 6500'
Saturday Morning 7500'
Saturday Afternoon 7500'
Snoqualmie Pass Elevation
Friday Morning 3500'
Friday Afternoon 5500'
Friday Evening 5500'
Friday Night 6500'
Saturday Morning 7500'
Saturday Afternoon 7500'
East North Elevation
Friday Morning 2500'
Friday Afternoon 5500'
Friday Evening 4500'
Friday Night 4000'
Saturday Morning 5500'
Saturday Afternoon 6500'
East Central Elevation
Friday Morning 3000'
Friday Afternoon 5500'
Friday Evening 5500'
Friday Night 6000'
Saturday Morning 7000'
Saturday Afternoon 7500'
East South Elevation
Friday Morning 3500'
Friday Afternoon 6000'
Friday Evening 6000'
Friday Night 6000'
Saturday Morning 7000'
Saturday Afternoon 8000'
Mt. Hood Elevation
Friday Morning 4000'
Friday Afternoon 6500'
Friday Evening 7000'
Friday Night 7500'
Saturday Morning 8000'
Saturday Afternoon 9000'

5000' Temperatures (°F)

Friday Friday Night
Max / Min Max / Min
Olympics 39 / 28 35 / 31
West North 36 / 24 34 / 30
West Central 37 / 23 35 / 31
West South 41 / 24 37 / 31
Stevens Pass 39 / 23 36 / 31
Snoqualmie Pass 38 / 24 35 / 31
East North 38 / 25 36 / 31
East Central 41 / 26 37 / 32
East South 43 / 26 38 / 31
Mt. Hood 42 / 27 38 / 32
Olympics 5000' Temperature Forecast
(Max / Min)
Friday 39 / 28
Friday Night 35 / 31
West North 5000' Temperature Forecast
(Max / Min)
Friday 36 / 24
Friday Night 34 / 30
West Central 5000' Temperature Forecast
(Max / Min)
Friday 37 / 23
Friday Night 35 / 31
West South 5000' Temperature Forecast
(Max / Min)
Friday 41 / 24
Friday Night 37 / 31
Stevens Pass 5000' Temperature Forecast
(Max / Min)
Friday 39 / 23
Friday Night 36 / 31
Snoqualmie Pass 5000' Temperature Forecast
(Max / Min)
Friday 38 / 24
Friday Night 35 / 31
East North 5000' Temperature Forecast
(Max / Min)
Friday 38 / 25
Friday Night 36 / 31
East Central 5000' Temperature Forecast
(Max / Min)
Friday 41 / 26
Friday Night 37 / 32
East South 5000' Temperature Forecast
(Max / Min)
Friday 43 / 26
Friday Night 38 / 31
Mt. Hood 5000' Temperature Forecast
(Max / Min)
Friday 42 / 27
Friday Night 38 / 32

Ridgeline Winds (mph)

Friday Morning Friday Afternoon Friday Evening Friday Night
Olympics W 0-10 W 5-15 W 0-10 SW 0-10
West North W 0-10 W 5-15 W 0-10 SW 0-10
West Central W 5-15 W 5-15 WNW 0-10 W 0-10
West South W 5-15 W 5-15 NW 5-15 W 0-10
Stevens Pass WNW 5-15 WNW 5-15 NW 0-10 W 0-10
Snoqualmie Pass WNW 10-20 WSW 5-15 NW 5-15 W 0-10
East North WNW 10-20 W 5-15 WNW 5-15 W 0-10
East Central WNW 10-20 W 10-20 W 5-15 W 0-10
East South WNW 5-15 W 10-20 W 5-15 W 0-10
Mt. Hood NW 5-15 NW 0-10 NW 0-10 W 0-10
Olympics Ridgeline Winds (mph)
Friday Morning W 0-10
Friday Afternoon W 5-15
Friday Evening W 0-10
Friday Night SW 0-10
West North Ridgeline Winds (mph)
Friday Morning W 0-10
Friday Afternoon W 5-15
Friday Evening W 0-10
Friday Night SW 0-10
West Central Ridgeline Winds (mph)
Friday Morning W 5-15
Friday Afternoon W 5-15
Friday Evening WNW 0-10
Friday Night W 0-10
West South Ridgeline Winds (mph)
Friday Morning W 5-15
Friday Afternoon W 5-15
Friday Evening NW 5-15
Friday Night W 0-10
Stevens Pass Ridgeline Winds (mph)
Friday Morning WNW 5-15
Friday Afternoon WNW 5-15
Friday Evening NW 0-10
Friday Night W 0-10
Snoqualmie Pass Ridgeline Winds (mph)
Friday Morning WNW 10-20
Friday Afternoon WSW 5-15
Friday Evening NW 5-15
Friday Night W 0-10
East North Ridgeline Winds (mph)
Friday Morning WNW 10-20
Friday Afternoon W 5-15
Friday Evening WNW 5-15
Friday Night W 0-10
East Central Ridgeline Winds (mph)
Friday Morning WNW 10-20
Friday Afternoon W 10-20
Friday Evening W 5-15
Friday Night W 0-10
East South Ridgeline Winds (mph)
Friday Morning WNW 5-15
Friday Afternoon W 10-20
Friday Evening W 5-15
Friday Night W 0-10
Mt. Hood Ridgeline Winds (mph)
Friday Morning NW 5-15
Friday Afternoon NW 0-10
Friday Evening NW 0-10
Friday Night W 0-10

Jump to: Weather Forecast I Precipitation I Snow Level I 5000' Temps I Ridgeline Winds I

Previous forecast from Mar 11, 2021

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).

The label LT, is shorthand for ‘less than’.