Issued: 2:36 PM PDT Monday, March 18, 2024
by Robert Hahn

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

Weather Synopsis

The strong high pressure bringing a taste of summer to the region keeps its grip on the region through Tuesday but gradually shifts southward. Freezing levels remain around 10500-11000 ft Monday night and lower to 9000-10000 ft on Tuesday. Overnight, expect low-level inversions to drop temperatures in deeper valley locations into the 30s (and perhaps 20s around Washington Pass). However, most 5000 ft locations will remain well above freezing with light winds. Tuesday's highs will be a few degrees cooler than Monday, with light WSW ridgeline winds increasing into the 10-15 mph range for the mountain gaps, east slopes of the Cascades, and Mt Hood by the afternoon.

The ridge flattens more significantly Tuesday night, opening the door to increasing high and low cloud cover. A weak open trough approaches from the WSW as the ridge shifts east. Clouds lower and thicken with a slight chance of rain and high-elevation snow in the morning, but increasing chances late in the day. Most light precipitation will be limited to near and west of the Cascade Crest, with snow levels in the 5500-6500 ft range. Most areas should have ridgeline winds in the 10-15 mph range, but moderate winds likely develop for Mt Hood.

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
Monday Night Unseasonably mild, mostly clear with a few thin high clouds, and light winds.
Tuesday Warm, mostly sunny with a few low clouds late in the day, and light winds.
Monday Night Unseasonably mild, mostly clear with a few thin high clouds, and light winds.
Tuesday Warm, mostly sunny with a few low clouds late in the day, and light winds.
Monday Night Unseasonably mild, mostly clear with a few thin high clouds, and light winds.
Tuesday Warm, mostly sunny with a few low clouds late in the day, and light winds.
Monday Night Unseasonably mild, clear, and light winds.
Tuesday Warm, mostly sunny with a few low clouds late in the day, and light winds.
Monday Night Unseasonably mild and mostly clear. Light ridgeline and variable shifting W wind at the Pass.
Tuesday Warm and mostly sunny. Increasing light ridgeline and W wind at the Pass.
Monday Night Unseasonably mild and mostly clear. Light ridgeline and variable shifting W wind at the Pass.
Tuesday Warm and mostly sunny. Increasing light ridgeline and W wind at the Pass.
Monday Night Unseasonably mild and clear. Low-level inversion forming below 5500 ft.
Tuesday Warm and mostly sunny. Low-level inversion mixing out around 10 AM.
Monday Night Unseasonably mild, clear, and light winds. Low-level inversion forming below 5000 ft.
Tuesday Warm and mostly sunny. Low-level inversion mixing out around 10 AM.
Monday Night Unseasonably mild, clear, and light winds. Low-level inversion forming below 5000 ft.
Tuesday Warm and mostly sunny. Low-level inversion mixing out around 10 AM.
Monday Night Unseasonably mild, clear, and light winds.
Tuesday Warm and mostly sunny with a few low clouds late in the day. Increasing light to occasionally moderate ridgeline winds

Precipitation (in)

Monday Night Tuesday Tuesday Night Wednesday
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)
Monday Night 0
Tuesday 0
Tuesday Night 0
Wednesday 0
Mt Baker Ski Area Precipitation (in)
Monday Night 0
Tuesday 0
Tuesday Night 0
Wednesday 0
Mt. Loop - Barlow Pass Precipitation (in)
Monday Night 0
Tuesday 0
Tuesday Night 0
Wednesday 0
Stevens Pass Precipitation (in)
Monday Night 0
Tuesday 0
Tuesday Night 0
Wednesday 0
Snoqualmie Pass Precipitation (in)
Monday Night 0
Tuesday 0
Tuesday Night 0
Wednesday 0
Crystal Mt Precipitation (in)
Monday Night 0
Tuesday 0
Tuesday Night 0
Wednesday 0
Paradise Precipitation (in)
Monday Night 0
Tuesday 0
Tuesday Night 0
Wednesday 0
White Pass Precipitation (in)
Monday Night 0
Tuesday 0
Tuesday Night 0
Wednesday 0
Washington Pass Precipitation (in)
Monday Night 0
Tuesday 0
Tuesday Night 0
Wednesday 0
Mission Ridge Precipitation (in)
Monday Night 0
Tuesday 0
Tuesday Night 0
Wednesday 0
Salmon la Sac - Gallagher Head Precipitation (in)
Monday Night 0
Tuesday 0
Tuesday Night 0
Wednesday 0
Tieton River - Darland Mt. Precipitation (in)
Monday Night 0
Tuesday 0
Tuesday Night 0
Wednesday 0
Mt Hood Meadows Precipitation (in)
Monday Night 0
Tuesday 0
Tuesday Night 0
Wednesday 0
Timberline Precipitation (in)
Monday Night 0
Tuesday 0
Tuesday Night 0
Wednesday 0

Snow Level (ft)

Monday Evening Monday Night Tuesday Morning Tuesday Afternoon Tuesday Evening Tuesday Night Wednesday Morning Wednesday Afternoon
Olympics 11000' 10500' 10000' 9000' 8500' 8000' 7500' 5500'
West North 11000' 10500' 9500' 8500' 8000' 7500' 7000' 5500'
West Central 11000' 10500' 10000' 9000' 8000' 7500' 7500' 6000'
West South 11000' 10500' 10000' 9500' 8500' 8500' 8000' 6500'
Stevens Pass 11000' 10500' 10000' 9000' 8500' 8000' 7500' 6500'
Snoqualmie Pass 11000' 10500' 10000' 9000' 8500' 8000' 7500' 6000'
East North 11000' 10500' 9500' 9000' 8500' 8000' 7500' 7500'
East Central 11000' 10500' 10000' 9500' 9000' 9000' 8500' 8000'
East South 11000' 10500' 10500' 10000' 9500' 9500' 9000' 8000'
Mt. Hood 11000' 11000' 10500' 10000' 10000' 10000' 9000' 7500'
Olympics Elevation
Monday Evening 11000'
Monday Night 10500'
Tuesday Morning 10000'
Tuesday Afternoon 9000'
Tuesday Evening 8500'
Tuesday Night 8000'
Wednesday Morning 7500'
Wednesday Afternoon 5500'
West North Elevation
Monday Evening 11000'
Monday Night 10500'
Tuesday Morning 9500'
Tuesday Afternoon 8500'
Tuesday Evening 8000'
Tuesday Night 7500'
Wednesday Morning 7000'
Wednesday Afternoon 5500'
West Central Elevation
Monday Evening 11000'
Monday Night 10500'
Tuesday Morning 10000'
Tuesday Afternoon 9000'
Tuesday Evening 8000'
Tuesday Night 7500'
Wednesday Morning 7500'
Wednesday Afternoon 6000'
West South Elevation
Monday Evening 11000'
Monday Night 10500'
Tuesday Morning 10000'
Tuesday Afternoon 9500'
Tuesday Evening 8500'
Tuesday Night 8500'
Wednesday Morning 8000'
Wednesday Afternoon 6500'
Stevens Pass Elevation
Monday Evening 11000'
Monday Night 10500'
Tuesday Morning 10000'
Tuesday Afternoon 9000'
Tuesday Evening 8500'
Tuesday Night 8000'
Wednesday Morning 7500'
Wednesday Afternoon 6500'
Snoqualmie Pass Elevation
Monday Evening 11000'
Monday Night 10500'
Tuesday Morning 10000'
Tuesday Afternoon 9000'
Tuesday Evening 8500'
Tuesday Night 8000'
Wednesday Morning 7500'
Wednesday Afternoon 6000'
East North Elevation
Monday Evening 11000'
Monday Night 10500'
Tuesday Morning 9500'
Tuesday Afternoon 9000'
Tuesday Evening 8500'
Tuesday Night 8000'
Wednesday Morning 7500'
Wednesday Afternoon 7500'
East Central Elevation
Monday Evening 11000'
Monday Night 10500'
Tuesday Morning 10000'
Tuesday Afternoon 9500'
Tuesday Evening 9000'
Tuesday Night 9000'
Wednesday Morning 8500'
Wednesday Afternoon 8000'
East South Elevation
Monday Evening 11000'
Monday Night 10500'
Tuesday Morning 10500'
Tuesday Afternoon 10000'
Tuesday Evening 9500'
Tuesday Night 9500'
Wednesday Morning 9000'
Wednesday Afternoon 8000'
Mt. Hood Elevation
Monday Evening 11000'
Monday Night 11000'
Tuesday Morning 10500'
Tuesday Afternoon 10000'
Tuesday Evening 10000'
Tuesday Night 10000'
Wednesday Morning 9000'
Wednesday Afternoon 7500'

5000' Temperatures (°F)

Monday Night Tuesday
Max / Min Max / Min
Olympics 48 / 40 49 / 39
West North 48 / 40 48 / 39
West Central 49 / 41 48 / 40
West South 53 / 42 53 / 41
Stevens Pass 51 / 39 52 / 40
Snoqualmie Pass 50 / 41 49 / 40
East North 49 / 40 51 / 39
East Central 51 / 41 52 / 41
East South 53 / 41 55 / 41
Mt. Hood 54 / 43 57 / 42
Olympics 5000' Temperature Forecast
(Max / Min)
Monday Night 48 / 40
Tuesday 49 / 39
West North 5000' Temperature Forecast
(Max / Min)
Monday Night 48 / 40
Tuesday 48 / 39
West Central 5000' Temperature Forecast
(Max / Min)
Monday Night 49 / 41
Tuesday 48 / 40
West South 5000' Temperature Forecast
(Max / Min)
Monday Night 53 / 42
Tuesday 53 / 41
Stevens Pass 5000' Temperature Forecast
(Max / Min)
Monday Night 51 / 39
Tuesday 52 / 40
Snoqualmie Pass 5000' Temperature Forecast
(Max / Min)
Monday Night 50 / 41
Tuesday 49 / 40
East North 5000' Temperature Forecast
(Max / Min)
Monday Night 49 / 40
Tuesday 51 / 39
East Central 5000' Temperature Forecast
(Max / Min)
Monday Night 51 / 41
Tuesday 52 / 41
East South 5000' Temperature Forecast
(Max / Min)
Monday Night 53 / 41
Tuesday 55 / 41
Mt. Hood 5000' Temperature Forecast
(Max / Min)
Monday Night 54 / 43
Tuesday 57 / 42

Ridgeline Winds (mph)

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

Extended Weather Synopsis

The weak open trough passes over the area Wednesday night with light rain and higher elevation snow at times. Some moisture continues after the trough, with W flow aloft on Thursday. Moisture decreases Thursday night as a closed low approaches the coastline, switching winds to the SW. Light rain and high-elevation snow return late in the day on Friday. Temperatures should be slightly above seasonal norms.

Extended Snow Level (ft)

Wednesday Night Thursday Thursday Night Friday *
West North 4500' 4000' 4500' 4500'
Snoqualmie Pass 4500' 4500' 5000' 5500'
Mt. Hood 5000' 5000' 6000' 7000'
West North Elevation
Wednesday Night 4500'
Thursday 4000'
Thursday Night 4500'
Friday * 4500'
Snoqualmie Pass Elevation
Wednesday Night 4500'
Thursday 4500'
Thursday Night 5000'
Friday * 5500'
Mt. Hood Elevation
Wednesday Night 5000'
Thursday 5000'
Thursday Night 6000'
Friday * 7000'

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

Previous forecast from Mar 18, 2024

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’.