Issued: 7:00 AM PDT Monday, March 20, 2023
by Robert Hahn

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

Weather Synopsis

A weakening trough stalls over the Pacific Northwest region. The trough has brought in cooler, more seasonable temperatures, and some light precipitation. On the downstream side of the trough, a band of mostly light rain and snow continues to lift northward across the central and northern Cascades as the day progresses. A surface low in eastern Washington will enhance NE winds along the east slopes of the Cascades, which in turn enhances light rain and snow for the Wenatchee Mountains and other far-eastern mountain areas. On the back side of the trough, winds have switched SW or WSW. Rain and snow showers extending from the Washington Coast to Olympia and south to the Oregon border on Monday morning remain light overall, but locally intense in convective cells. These showers should drift ENE, enhancing shower activity along the west slopes of the Cascades from mid-morning through the evening hours and gradually taper overnight. Expect some weak convergence during the evening hours to focus on the Mountain Loop vicinity. Snow levels lower from around 3500 ft on Monday to Snoqualmie Pass level overnight night.

Flow begins to split around the region on Tuesday, allowing the region to mostly dry out, but expect just enough instability for an isolated rain/snow shower with snow levels rising from 3000 to around 4000 ft.

 

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 Light rain and snow showers, increasing in the northern Olympics during the afternoon.
Monday Night Light rain and snow showers.
Monday Periods of light rain and snow.
Monday Night Rain and snow showers peak during the evening, then decrease.
Monday Periods of light rain and snow.
Monday Night Rain/snow showers and weak convergence during the evening hours. Rain/snow decreases overnight.
Monday Light rain and snow showers, heaviest at Paradise.
Monday Night Decreasing light rain and snow showers, heaviest at Paradise.
Monday Increasing periods of light rain or snow, becoming showery during the afternoon. Increasing light ridgeline and W wind at the Pass.
Monday Night Decreasing light rain/snow showers. Light ridgeline and W wind becoming variable at the Pass by morning.
Monday Light to occasionally moderate rain and snow showers, decrease in the afternoon. Increasing light to occasionally moderate ridgeline and light W wind at the Pass.
Monday Night Decreasing light rain/snow showers. Light ridgeline and W wind becoming variable at the Pass by morning.
Monday Increasing periods of light rain or snow.
Monday Night Decreasing light rain or snow showers.
Monday Periods of light to occasionally moderate rain or snow.
Monday Night Decreasing light rain or snow showers.
Monday Light rain or snow showers mainly near the Cascade Crest.
Monday Night Very light rain or snow showers.
Monday Light rain or snow showers. Decreasing moderate ridgeline winds.
Monday Night Light rain or snow showers in the evening, decrease or end overnight.

Issued: 7:00 AM PDT Monday, March 20, 2023

Precipitation (in)

Monday Monday Night Tuesday
5 am - 5 pm 5 pm - 5 am 5 am - 5 pm
Hurricane Ridge LT 0.10 LT 0.10 LT 0.10
Mt Baker Ski Area LT 0.25 0.25 LT 0.10
Mt. Loop - Barlow Pass 0.25 0.25 LT 0.10
Stevens Pass 0.25 0.25 LT 0.10
Snoqualmie Pass 0.25 - 0.50 LT 0.25 LT 0.10
Crystal Mt LT 0.25 LT 0.10 LT 0.10
Paradise 0.25 - 0.50 LT 0.25 LT 0.10
White Pass LT 0.25 LT 0.10 LT 0.10
Washington Pass LT 0.25 LT 0.25 LT 0.10
Mission Ridge 0.25 LT 0.25 LT 0.10
Salmon la Sac - Gallagher Head 0.25 LT 0.25 LT 0.10
Tieton River - Darland Mt. LT 0.10 LT 0.10 0
Mt Hood Meadows LT 0.25 LT 0.25 0
Timberline 0.25 LT 0.25 0
Hurricane Ridge Precipitation (in)
Monday LT 0.10
Monday Night LT 0.10
Tuesday LT 0.10
Mt Baker Ski Area Precipitation (in)
Monday LT 0.25
Monday Night 0.25
Tuesday LT 0.10
Mt. Loop - Barlow Pass Precipitation (in)
Monday 0.25
Monday Night 0.25
Tuesday LT 0.10
Stevens Pass Precipitation (in)
Monday 0.25
Monday Night 0.25
Tuesday LT 0.10
Snoqualmie Pass Precipitation (in)
Monday 0.25 - 0.50
Monday Night LT 0.25
Tuesday LT 0.10
Crystal Mt Precipitation (in)
Monday LT 0.25
Monday Night LT 0.10
Tuesday LT 0.10
Paradise Precipitation (in)
Monday 0.25 - 0.50
Monday Night LT 0.25
Tuesday LT 0.10
White Pass Precipitation (in)
Monday LT 0.25
Monday Night LT 0.10
Tuesday LT 0.10
Washington Pass Precipitation (in)
Monday LT 0.25
Monday Night LT 0.25
Tuesday LT 0.10
Mission Ridge Precipitation (in)
Monday 0.25
Monday Night LT 0.25
Tuesday LT 0.10
Salmon la Sac - Gallagher Head Precipitation (in)
Monday 0.25
Monday Night LT 0.25
Tuesday LT 0.10
Tieton River - Darland Mt. Precipitation (in)
Monday LT 0.10
Monday Night LT 0.10
Tuesday 0
Mt Hood Meadows Precipitation (in)
Monday LT 0.25
Monday Night LT 0.25
Tuesday 0
Timberline Precipitation (in)
Monday 0.25
Monday Night LT 0.25
Tuesday 0

Issued: 7:00 AM PDT Monday, March 20, 2023

Snow Level (ft)

Monday Morning Monday Afternoon Monday Evening Monday Night Tuesday Morning* Tuesday Afternoon*
Olympics 3500' 3500' 3500' 3000' 3500' 4000'
West North 4000' 3500' 3500' 3000' 3000' 4000'
West Central 3500' 3500' 3000' 3000' 2500' 4000'
West South 3500' 3500' 3500' 2500' 25000' 4000'
Stevens Pass 3500' 3500' 3500' 3000' 3000' 4000'
Snoqualmie Pass 3500' 3500' 3500' 3000' 3000' 4000'
East North 4000' 4000' 4000' 3500' 3000' 4000'
East Central 4000' 4000' 3500' 3000' 3000' 4000'
East South 3500' 4000' 3500' 2500' 2500' 4500'
Mt. Hood 3000' 3000' 2500' 2500' 2500' 4500'
Olympics Elevation
Monday Morning 3500'
Monday Afternoon 3500'
Monday Evening 3500'
Monday Night 3000'
Tuesday Morning* 3500'
Tuesday Afternoon* 4000'
West North Elevation
Monday Morning 4000'
Monday Afternoon 3500'
Monday Evening 3500'
Monday Night 3000'
Tuesday Morning* 3000'
Tuesday Afternoon* 4000'
West Central Elevation
Monday Morning 3500'
Monday Afternoon 3500'
Monday Evening 3000'
Monday Night 3000'
Tuesday Morning* 2500'
Tuesday Afternoon* 4000'
West South Elevation
Monday Morning 3500'
Monday Afternoon 3500'
Monday Evening 3500'
Monday Night 2500'
Tuesday Morning* 25000'
Tuesday Afternoon* 4000'
Stevens Pass Elevation
Monday Morning 3500'
Monday Afternoon 3500'
Monday Evening 3500'
Monday Night 3000'
Tuesday Morning* 3000'
Tuesday Afternoon* 4000'
Snoqualmie Pass Elevation
Monday Morning 3500'
Monday Afternoon 3500'
Monday Evening 3500'
Monday Night 3000'
Tuesday Morning* 3000'
Tuesday Afternoon* 4000'
East North Elevation
Monday Morning 4000'
Monday Afternoon 4000'
Monday Evening 4000'
Monday Night 3500'
Tuesday Morning* 3000'
Tuesday Afternoon* 4000'
East Central Elevation
Monday Morning 4000'
Monday Afternoon 4000'
Monday Evening 3500'
Monday Night 3000'
Tuesday Morning* 3000'
Tuesday Afternoon* 4000'
East South Elevation
Monday Morning 3500'
Monday Afternoon 4000'
Monday Evening 3500'
Monday Night 2500'
Tuesday Morning* 2500'
Tuesday Afternoon* 4500'
Mt. Hood Elevation
Monday Morning 3000'
Monday Afternoon 3000'
Monday Evening 2500'
Monday Night 2500'
Tuesday Morning* 2500'
Tuesday Afternoon* 4500'

Issued: 7:00 AM PDT Monday, March 20, 2023

5000' Temperatures (°F)

Monday Monday Night
Max / Min Max / Min
Olympics 33 / 29 31 / 26
West North 33 / 31 31 / 27
West Central 32 / 31 30 / 26
West South 32 / 29 30 / 24
Stevens Pass 32 / 29 31 / 27
Snoqualmie Pass 32 / 29 30 / 27
East North 35 / 27 32 / 26
East Central 34 / 29 32 / 26
East South 33 / 29 31 / 25
Mt. Hood 32 / 27 30 / 24
Olympics 5000' Temperature Forecast
(Max / Min)
Monday 33 / 29
Monday Night 31 / 26
West North 5000' Temperature Forecast
(Max / Min)
Monday 33 / 31
Monday Night 31 / 27
West Central 5000' Temperature Forecast
(Max / Min)
Monday 32 / 31
Monday Night 30 / 26
West South 5000' Temperature Forecast
(Max / Min)
Monday 32 / 29
Monday Night 30 / 24
Stevens Pass 5000' Temperature Forecast
(Max / Min)
Monday 32 / 29
Monday Night 31 / 27
Snoqualmie Pass 5000' Temperature Forecast
(Max / Min)
Monday 32 / 29
Monday Night 30 / 27
East North 5000' Temperature Forecast
(Max / Min)
Monday 35 / 27
Monday Night 32 / 26
East Central 5000' Temperature Forecast
(Max / Min)
Monday 34 / 29
Monday Night 32 / 26
East South 5000' Temperature Forecast
(Max / Min)
Monday 33 / 29
Monday Night 31 / 25
Mt. Hood 5000' Temperature Forecast
(Max / Min)
Monday 32 / 27
Monday Night 30 / 24

Issued: 7:00 AM PDT Monday, March 20, 2023

Ridgeline Winds (mph)

Monday Morning Monday Afternoon Monday Evening Monday Night
Olympics SSW 0-10 SW 5-15 SSW 0-10 SE 0-10
West North SE 0-10 SSW 0-10 SW 0-10 S 0-10
West Central S 5-15 WSW 5-15 W 5-15 WSW 5-15
West South SW 10-20 SW 5-15 WSW 0-10 WSW 0-10
Stevens Pass ESE 0-10 W 5-15 W 5-15 W 5-15
Snoqualmie Pass SW 5-15 W 10-20 W 5-15 W 5-15
East North E 5-15 SE 0-10 W 5-15 W 5-15
East Central NNE 0-10 NW 5-15 WNW 5-15 WNW 5-15
East South W 10-20 W 5-15 W 5-15 SW 0-10
Mt. Hood WSW 20-30 WSW 20-30 WSW 10-20 SSW 0-10
Olympics Ridgeline Winds (mph)
Monday Morning SSW 0-10
Monday Afternoon SW 5-15
Monday Evening SSW 0-10
Monday Night SE 0-10
West North Ridgeline Winds (mph)
Monday Morning SE 0-10
Monday Afternoon SSW 0-10
Monday Evening SW 0-10
Monday Night S 0-10
West Central Ridgeline Winds (mph)
Monday Morning S 5-15
Monday Afternoon WSW 5-15
Monday Evening W 5-15
Monday Night WSW 5-15
West South Ridgeline Winds (mph)
Monday Morning SW 10-20
Monday Afternoon SW 5-15
Monday Evening WSW 0-10
Monday Night WSW 0-10
Stevens Pass Ridgeline Winds (mph)
Monday Morning ESE 0-10
Monday Afternoon W 5-15
Monday Evening W 5-15
Monday Night W 5-15
Snoqualmie Pass Ridgeline Winds (mph)
Monday Morning SW 5-15
Monday Afternoon W 10-20
Monday Evening W 5-15
Monday Night W 5-15
East North Ridgeline Winds (mph)
Monday Morning E 5-15
Monday Afternoon SE 0-10
Monday Evening W 5-15
Monday Night W 5-15
East Central Ridgeline Winds (mph)
Monday Morning NNE 0-10
Monday Afternoon NW 5-15
Monday Evening WNW 5-15
Monday Night WNW 5-15
East South Ridgeline Winds (mph)
Monday Morning W 10-20
Monday Afternoon W 5-15
Monday Evening W 5-15
Monday Night SW 0-10
Mt. Hood Ridgeline Winds (mph)
Monday Morning WSW 20-30
Monday Afternoon WSW 20-30
Monday Evening WSW 10-20
Monday Night SSW 0-10

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

Previous forecast from Mar 19, 2023

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’.