Issued: 2:58 PM PST Tuesday, March 6, 2018
by Dennis D'Amico

Jump to: Weather Forecast I Snow/Freezing Level I Precipitation I Free Winds 5k I Free Winds 9k I Extended Weather

Weather Synopsis for Tuesday & Friday

Upper level ridging will build offshore today with a dry and eventually sunny day forecast across the Pacific Northwest. Before the sunshine, a mid level cloud deck is hanging tough around for the Olympics and central and north Cascades this morning while clearer skies are seen further south.  In the cloudier areas, skies should clear later this morning with just some afternoon cumulus buildup expected.  Mostly clear and dry weather will continue overnight. 

Flat upper level ridging will move over the region on Wednesday, with freezing levels rising further. However, a closed upper low well off the California coast will spread mid and high clouds over the region from the south during the day, dampening an otherwise warm day for early March.  A weakening frontal band extending from the low pressure system will pass over the area Wednesday night producing light precipitation. 

Weather Forecast

Olympics
Tuesday Partly to mostly sunny.
Tuesday Night Mostly clear.
Wednesday Mostly cloudy becoming cloudy with increasing mid and high level clouds during the day. Mild.
Wednesday Night Light rain and snow developing after midnight.
Washington Cascades near and west of the Crest including Stevens, Snoqualmie and White Passes
Tuesday Partly to mostly sunny north Cascades. Mostly sunny central and south.
Tuesday Night Mostly clear.
Wednesday Mostly cloudy becoming cloudy with increasing mid and high level clouds during the day. Mild.
Wednesday Night Light rain and snow developing after midnight.
East Slopes of the Washington Cascades
Tuesday Partly to mostly sunny northeast Cascades. Mostly sunny central-east and southeast.
Tuesday Night Mostly clear.
Wednesday Mostly cloudy becoming cloudy with increasing mid and high level clouds during the day. Mild.
Wednesday Night Light rain and snow developing after midnight.
Mt. Hood
Tuesday Mostly sunny.
Tuesday Night Mostly clear.
Wednesday Mostly cloudy becoming cloudy with increasing mid and high level clouds during the day. Mild.
Wednesday Night Light rain and snow developing.

Issued: 2:58 PM PST Tuesday, March 6, 2018

Snow/Freezing Level (ft)

Hurricane Ridge Mt. Baker Washington Pass Leavenworth Stevens Pass Snoqualmie Pass Mt. Rainier, Crystal & White Pass Mt. Hood
Tuesday Afternoon Freezing Level 3500' 3500' 4000' ' ' 4000' ' 5000'
Tuesday Night Freezing Level 3500' 2000' 500' ' ' 2000' ' 4500'
Wednesday Morning Freezing Level 4500' 3500' 3000' ' ' 4000' ' 6000'
Wednesday Afternoon Freezing Level 7000' 6000' 5500' ' ' 6500' ' 8000'
Wednesday Night Snow Level * 4500' 4000' 3000' ' ' 4000' ' 4500'
Hurricane Ridge Elevation
Tuesday Afternoon Freezing Level
3500'
Tuesday Night Freezing Level
3500'
Wednesday Morning Freezing Level
4500'
Wednesday Afternoon Freezing Level
7000'
Wednesday Night Snow Level
4500'
(Easterly Flow *)
Mt. Baker Elevation
Tuesday Afternoon Freezing Level
3500'
Tuesday Night Freezing Level
2000'
Wednesday Morning Freezing Level
3500'
Wednesday Afternoon Freezing Level
6000'
Wednesday Night Snow Level
4000'
(Easterly Flow *)
Washington Pass Elevation
Tuesday Afternoon Freezing Level
4000'
Tuesday Night Freezing Level
500'
Wednesday Morning Freezing Level
3000'
Wednesday Afternoon Freezing Level
5500'
Wednesday Night Snow Level
3000'
(Easterly Flow *)
Leavenworth Elevation
Tuesday Afternoon Freezing Level
'
Tuesday Night Freezing Level
'
Wednesday Morning Freezing Level
'
Wednesday Afternoon Freezing Level
'
Wednesday Night Snow Level
'
(Easterly Flow *)
Stevens Pass Elevation
Tuesday Afternoon Freezing Level
'
Tuesday Night Freezing Level
'
Wednesday Morning Freezing Level
'
Wednesday Afternoon Freezing Level
'
Wednesday Night Snow Level
'
(Easterly Flow *)
Snoqualmie Pass Elevation
Tuesday Afternoon Freezing Level
4000'
Tuesday Night Freezing Level
2000'
Wednesday Morning Freezing Level
4000'
Wednesday Afternoon Freezing Level
6500'
Wednesday Night Snow Level
4000'
(Easterly Flow *)
Mt. Rainier & Crystal Elevation
Tuesday Afternoon Freezing Level
'
Tuesday Night Freezing Level
'
Wednesday Morning Freezing Level
'
Wednesday Afternoon Freezing Level
'
Wednesday Night Snow Level
'
(Easterly Flow *)
Mt. Hood Elevation
Tuesday Afternoon Freezing Level
5000'
Tuesday Night Freezing Level
4500'
Wednesday Morning Freezing Level
6000'
Wednesday Afternoon Freezing Level
8000'
Wednesday Night Snow Level
4500'
(Easterly Flow *)

* Easterly flow in the Cascade Passes can cause locally lower Snow or Freezing levels than areas further west.
Freezing Level is when no precipitation is forecast.

Precipitation Forecast

Friday Friday
Hurricane Ridge LT 0.10 LT 0.10
Mt Baker Ski Area LT 0.10 LT 0.10
Washington Pass LT 0.10 LT 0.10
Stevens Pass LT 0.10 LT 0.10
Snoqualmie Pass LT 0.10 LT 0.25
Mission Ridge LT 0.10 LT 0.10
Crystal Mt LT 0.10 LT 0.10
Paradise LT 0.10 LT 0.25
White Pass LT 0.10 LT 0.10
Mt Hood Meadows LT 0.10 LT 0.10
Timberline LT 0.10 LT 0.10

LT = less than; WE or Water equivalent is the liquid water equivalent of melted snow in hundredths of inches. As a rough approximation 1 inch of snow = about .10 inches WE, or 10 inches of snow = about 1 inch WE.

Issued: 2:58 PM PST Tuesday, March 6, 2018

Free Winds at 5000' (mph)

Hurricane Ridge Mt. Baker Stevens to Snoqualmie Pass Mt. Rainier Mt. Hood
Tuesday Afternoon VAR 0 - 10 VAR 0 - 10 E 0 - 10 --- - E 0 - 10
Tuesday Night E 0 - 10 S 0 - 10 E 5 - 15 --- - SE 0 - 10
Wednesday Morning SE 0 - 10 SE 0 - 10 E 5 - 15 --- - SE 5 - 15
Wednesday Afternoon S 0 - 10 SE 0 - 10 SE 5 - 15 --- - SE 5 - 15
Wednesday Night S 10 - 20 SE 5 - 15 SE 5 - 15 --- - SW 5 - 15
Hurricane Ridge Elevation
Tuesday Afternoon VAR 0 - 10
Tuesday Night E 0 - 10
Wednesday Morning SE 0 - 10
Wednesday Afternoon S 0 - 10
Wednesday Night S 10 - 20
Mt. Baker Elevation
Tuesday Afternoon VAR 0 - 10
Tuesday Night S 0 - 10
Wednesday Morning SE 0 - 10
Wednesday Afternoon SE 0 - 10
Wednesday Night SE 5 - 15
Stevens and Snoqualmie Pass Elevation
Tuesday Afternoon E 0 - 10
Tuesday Night E 5 - 15
Wednesday Morning E 5 - 15
Wednesday Afternoon SE 5 - 15
Wednesday Night SE 5 - 15
Mt. Rainier Elevation
Tuesday Afternoon --- -
Tuesday Night --- -
Wednesday Morning --- -
Wednesday Afternoon --- -
Wednesday Night --- -
Mt. Hood Elevation
Tuesday Afternoon E 0 - 10
Tuesday Night SE 0 - 10
Wednesday Morning SE 5 - 15
Wednesday Afternoon SE 5 - 15
Wednesday Night SW 5 - 15
Hurricane Ridge Direction - Speed
Tuesday Afternoon VAR 0 - 10
Tuesday Night E 0 - 10
Wednesday Morning SE 0 - 10
Wednesday Afternoon S 0 - 10
Wednesday Night S 10 - 20
Mt. Baker Direction - Speed
Tuesday Afternoon VAR 0 - 10
Tuesday Night S 0 - 10
Wednesday Morning SE 0 - 10
Wednesday Afternoon SE 0 - 10
Wednesday Night SE 5 - 15
Stevens and Snoqualmie Pass Direction - Speed
Tuesday Afternoon E 0 - 10
Tuesday Night E 5 - 15
Wednesday Morning E 5 - 15
Wednesday Afternoon SE 5 - 15
Wednesday Night SE 5 - 15
Mt. Rainier Direction - Speed
Tuesday Afternoon --- -
Tuesday Night --- -
Wednesday Morning --- -
Wednesday Afternoon --- -
Wednesday Night --- -
Mt. Hood Direction - Speed
Tuesday Afternoon E 0 - 10
Tuesday Night SE 0 - 10
Wednesday Morning SE 5 - 15
Wednesday Afternoon SE 5 - 15
Wednesday Night SW 5 - 15

Directions above indicate the direction the wind blows from on the 16-point cardinal scale. These winds indicate "free" winds, or those winds in the atmosphere not influenced by terrain. Topographical effects may produce greater or lower wind speeds in certain locations as well as significant variations in direction.

Free Winds at 9000' (mph)

Mt. Baker Washington Pass Stevens to Snoqualmie Pass Mt. Rainier Mt. Hood
Tuesday Afternoon W 10 - 20 WSW 5 - 15 W 10 - 20 --- - SW 10 - 20
Tuesday Night SW 10 - 20 SW 10 - 20 SW 10 - 20 --- - SW 15 - 25
Wednesday Morning SW 10 - 20 SW 10 - 20 SW 15 - 25 --- - SW 10 - 20
Wednesday Afternoon SW 15 - 25 SW 15 - 25 SW 15 - 25 --- - SSW 15 - 25
Wednesday Night SW 15 - 25 SW 15 - 25 SW 25 - 35 --- - SW 25 - 35
Mt. Baker Direction - Speed
Tuesday Afternoon W 10 - 20
Tuesday Night SW 10 - 20
Wednesday Morning SW 10 - 20
Wednesday Afternoon SW 15 - 25
Wednesday Night SW 15 - 25
Washington Pass Direction - Speed
Tuesday Afternoon WSW 5 - 15
Tuesday Night SW 10 - 20
Wednesday Morning SW 10 - 20
Wednesday Afternoon SW 15 - 25
Wednesday Night SW 15 - 25
Stevens and Snoqualmie Pass Direction - Speed
Tuesday Afternoon W 10 - 20
Tuesday Night SW 10 - 20
Wednesday Morning SW 15 - 25
Wednesday Afternoon SW 15 - 25
Wednesday Night SW 25 - 35
Mt. Rainier Direction - Speed
Tuesday Afternoon --- -
Tuesday Night --- -
Wednesday Morning --- -
Wednesday Afternoon --- -
Wednesday Night --- -
Mt. Hood Direction - Speed
Tuesday Afternoon SW 10 - 20
Tuesday Night SW 15 - 25
Wednesday Morning SW 10 - 20
Wednesday Afternoon SSW 15 - 25
Wednesday Night SW 25 - 35

Directions above indicate the direction the wind blows from on the 16-point cardinal scale. These winds indicate "free" winds, or those winds in the atmosphere not influenced by terrain. Topographical effects may produce greater or lower wind speeds in certain locations as well as significant variations in direction.

Issued: 2:58 PM PST Tuesday, March 6, 2018

Extended Weather Synopsis for Friday night through Friday

The weather pattern will quickly turn more active beginning Thursday as the upper level ridge over the area on Wednesday shifts inland. The aforementioned low pressure system will track towards the NW tip of the Olympic Peninsula on Thursday, passing into southern British Columbia Thursday evening. This system should pack a good punch of precipitation and winds as it traverses the area. With the current track, SW flow will keep snow levels in 4000-4500 range over much of the area Thursday and Thursday evening.  It remains to be seen how much if any effect easterly flow has on precipitation type in the Passes this late in the year. Winds will peak Thursday afternoon and evening. Behind the front a slow cooling trend should ensue Thursday night with much colder air moving Friday. Significant post-frontal shower activity will wane Friday afternoon as upper level ridging begins to build over the area. Saturday looks mostly dry, but forecast models disagree if an embedded shortwave in southerly flow will bring some cloud cover.  

Extended Weather

Olympics, Washington Cascades and Mt. Hood Area
Thursday Periods of light rain and snow in the morning becoming light to moderate rain and snow in the afternoon. Winds increasing through the day, becoming strong in the alpine in the afternoon. Friday Light to moderate rain and snow showers in the morning becoming scattered light to occasionally moderate showers in the afternoon. Cooling trend. Saturday Partly sunny. Thursday Night Light to moderate rain and snow showers. Windy Friday Night Mostly cloudy with showers tapering off overnight.

Extended Snow/Freezing Levels

Mt. Baker Snoqualmie Pass Mt. Hood Easterly Flow *
Thursday Snow Level 3500' - 4500' 4000' - 4500' 4000' - 5000' *
Thursday Night Snow Level 3500' - 4500' 3500' - 4500' 4500' - 5500'
Friday Snow Level 2000' - 3000' 2000' - 3000' 3000' - 4000'
Friday Night Snow Level 1500' - 2500' 1500' - 2500' 3000' - 4000'
Saturday Freezing Level 3500' - 4500' 3500' - 4500' 4500' - 5500'
Mt. Baker Elevation
Thursday Snow Level
3500' - 4500'
(Easterly Flow *)
Thursday Night Snow Level
3500' - 4500'
Friday Snow Level
2000' - 3000'
Friday Night Snow Level
1500' - 2500'
Saturday Freezing Level
3500' - 4500'
Snoqualmie Pass Elevation
Thursday Snow Level
4000' - 4500'
(Easterly Flow *)
Thursday Night Snow Level
3500' - 4500'
Friday Snow Level
2000' - 3000'
Friday Night Snow Level
1500' - 2500'
Saturday Freezing Level
3500' - 4500'
Mt. Hood Elevation
Thursday Snow Level
4000' - 5000'
(Easterly Flow *)
Thursday Night Snow Level
4500' - 5500'
Friday Snow Level
3000' - 4000'
Friday Night Snow Level
3000' - 4000'
Saturday Freezing Level
4500' - 5500'

* Easterly flow in the Cascade Passes can cause locally lower Snow or Freezing levels than areas further west.
Freezing Level is when no precipitation is forecast.

Jump to: Weather Forecast I Snow/Freezing Level I Precipitation I Free Winds 5k I Free Winds 9k I Extended Weather

Previous forecast from Mar 6, 2018

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