Issued: 2:56 PM PST Tuesday, February 23, 2016
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 & Saturday

Afternoon update: Minor changes

High pressure will dominate our weather today as an upper level ridge centered along the coast slowly shifts inland. Strong surface high pressure to our east will produce moderate offshore flow today.

Free air freezing levels will be on the rise with 9000+ foot freezing levels forecast over the Olympics by Tuesday afternoon. However cold air along the east slopes and easterly flow will help suppress a rapid warming for the Cascades and Mt. Hood. Breezy E-SE winds at Pass level and for south and central Cascade ridge-lines exposed to east flow will diminish Tuesday night. High clouds associated with a weak upper level shortwave should reach the Olympics this afternoon with increasing clouds moving inland overnight.  

The weak upper level shortwave should dampen the upper level ridge on Wednesday but only amount to a few sprinkles for the Olympics and northwest Cascades with a mix of mid and high clouds elsewhere. A mix of sun and clouds will linger through Wednesday afternoon. 

Weather Forecast

Olympics
Tuesday

Mostly sunny with increasing high clouds in the afternoon. Warming trend. 
Tuesday Night - Wednesday Morning

Mostly cloudy. Chance of light rain or snow. 
Wednesday Afternoon - Wednesday Night

Partly cloudy becoming mostly clear overnight. 
Washington Cascades near and west of the crest including Stevens, Snoqualmie, and White Passes
Tuesday

Mostly sunny except for areas of low clouds near the Cascade Passes and sheltered valleys. Multiple freezing levels due to temperature inversions and easterly flow. Breezy Cascades Passes and ridge-lines in the central and south Cascades exposed to east winds. 
Tuesday Night - Wednesday Morning

Increasing high clouds overnight. Chance of very light rain or snow north Cascades late tonight.
Wednesday Afternoon - Wednesday Night

Partly cloudy becoming mostly clear overnight. 
East slopes of the Washington Cascades
Tuesday Afternoon - Wednesday Morning

Mostly clear in the afternoon, increasing high clouds overnight.
Wednesday Afternoon - Wednesday Night

Partly cloudy with periods of mid and high clouds. Slow warming trend. 
Mt. Hood Area
Tuesday Afternoon - Wednesday Morning

Mostly clear in the afternoon. Increasing high clouds overnight. Multiple freezing levels due to temperature inversions and easterly flow. Slow warming trend. 
Wednesday Afternoon - Wednesday Night

Partly cloudy with periods of mid and high clouds becoming mostly clear overnight. 

Issued: 2:56 PM PST Tuesday, February 23, 2016

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 * 8500' 6000' 3500' ' ' 4500' ' 7000'
Tuesday Night - Wednesday Morning Freezing Level * 6500' 6000' 3000' ' ' 6000' ' 7000'
Wednesday Afternoon - Wednesday Night Freezing Level * 6500' 6500' 5500' ' ' 6500' ' 7500'
Hurricane Ridge Elevation
Tuesday Afternoon Freezing Level
8500'
(Easterly Flow *)
Tuesday Night - Wednesday Morning Freezing Level
6500'
(Easterly Flow *)
Wednesday Afternoon - Wednesday Night Freezing Level
6500'
(Easterly Flow *)
Mt. Baker Elevation
Tuesday Afternoon Freezing Level
6000'
(Easterly Flow *)
Tuesday Night - Wednesday Morning Freezing Level
6000'
(Easterly Flow *)
Wednesday Afternoon - Wednesday Night Freezing Level
6500'
(Easterly Flow *)
Washington Pass Elevation
Tuesday Afternoon Freezing Level
3500'
(Easterly Flow *)
Tuesday Night - Wednesday Morning Freezing Level
3000'
(Easterly Flow *)
Wednesday Afternoon - Wednesday Night Freezing Level
5500'
(Easterly Flow *)
Leavenworth Elevation
Tuesday Afternoon Freezing Level
'
(Easterly Flow *)
Tuesday Night - Wednesday Morning Freezing Level
'
(Easterly Flow *)
Wednesday Afternoon - Wednesday Night Freezing Level
'
(Easterly Flow *)
Stevens Pass Elevation
Tuesday Afternoon Freezing Level
'
(Easterly Flow *)
Tuesday Night - Wednesday Morning Freezing Level
'
(Easterly Flow *)
Wednesday Afternoon - Wednesday Night Freezing Level
'
(Easterly Flow *)
Snoqualmie Pass Elevation
Tuesday Afternoon Freezing Level
4500'
(Easterly Flow *)
Tuesday Night - Wednesday Morning Freezing Level
6000'
(Easterly Flow *)
Wednesday Afternoon - Wednesday Night Freezing Level
6500'
(Easterly Flow *)
Mt. Rainier & Crystal Elevation
Tuesday Afternoon Freezing Level
'
(Easterly Flow *)
Tuesday Night - Wednesday Morning Freezing Level
'
(Easterly Flow *)
Wednesday Afternoon - Wednesday Night Freezing Level
'
(Easterly Flow *)
Mt. Hood Elevation
Tuesday Afternoon Freezing Level
7000'
(Easterly Flow *)
Tuesday Night - Wednesday Morning Freezing Level
7000'
(Easterly Flow *)
Wednesday Afternoon - Wednesday Night Freezing Level
7500'
(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

Saturday Saturday
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 0.10
Mission Ridge LT 0.10 LT 0.10
Crystal Mt LT 0.10 LT 0.10
Paradise LT 0.10 LT 0.10
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: 2:56 PM PST Tuesday, February 23, 2016

Free Winds at 5000' (mph)

Hurricane Ridge Mt. Baker Stevens to Snoqualmie Pass Mt. Rainier Mt. Hood
Tuesday Afternoon SE 5 - 15 E 0 - 10 ESE 15 - 30 --- - ESE 10 - 25
Tuesday Night - Wednesday Morning S 5 - 15 S 0 - 10 SE 5 - 15 --- - S 5 - 15
Wednesday Afternoon - Wednesday Night S 0 - 10 S 0 - 10 SW 0 - 10 --- - S 0 - 10
Hurricane Ridge Elevation
Tuesday Afternoon SE 5 - 15
Tuesday Night - Wednesday Morning S 5 - 15
Wednesday Afternoon - Wednesday Night S 0 - 10
Mt. Baker Elevation
Tuesday Afternoon E 0 - 10
Tuesday Night - Wednesday Morning S 0 - 10
Wednesday Afternoon - Wednesday Night S 0 - 10
Stevens and Snoqualmie Pass Elevation
Tuesday Afternoon ESE 15 - 30
Tuesday Night - Wednesday Morning SE 5 - 15
Wednesday Afternoon - Wednesday Night SW 0 - 10
Mt. Rainier Elevation
Tuesday Afternoon --- -
Tuesday Night - Wednesday Morning --- -
Wednesday Afternoon - Wednesday Night --- -
Mt. Hood Elevation
Tuesday Afternoon ESE 10 - 25
Tuesday Night - Wednesday Morning S 5 - 15
Wednesday Afternoon - Wednesday Night S 0 - 10
Hurricane Ridge Direction - Speed
Tuesday Afternoon SE 5 - 15
Tuesday Night - Wednesday Morning S 5 - 15
Wednesday Afternoon - Wednesday Night S 0 - 10
Mt. Baker Direction - Speed
Tuesday Afternoon E 0 - 10
Tuesday Night - Wednesday Morning S 0 - 10
Wednesday Afternoon - Wednesday Night S 0 - 10
Stevens and Snoqualmie Pass Direction - Speed
Tuesday Afternoon ESE 15 - 30
Tuesday Night - Wednesday Morning SE 5 - 15
Wednesday Afternoon - Wednesday Night SW 0 - 10
Mt. Rainier Direction - Speed
Tuesday Afternoon --- -
Tuesday Night - Wednesday Morning --- -
Wednesday Afternoon - Wednesday Night --- -
Mt. Hood Direction - Speed
Tuesday Afternoon ESE 10 - 25
Tuesday Night - Wednesday Morning S 5 - 15
Wednesday Afternoon - Wednesday Night S 0 - 10

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 - Tuesday Night SW 10 - 20 WSW 10 - 20 SW 15 - 30 --- - SW 15 - 30
Wednesday - Wednesday Night SW 5 - 15 WSW 5 - 15 SW 10 - 20 --- - SW 15 - 25
Mt. Baker Direction - Speed
Tuesday Afternoon - Tuesday Night SW 10 - 20
Wednesday - Wednesday Night SW 5 - 15
Washington Pass Direction - Speed
Tuesday Afternoon - Tuesday Night WSW 10 - 20
Wednesday - Wednesday Night WSW 5 - 15
Stevens and Snoqualmie Pass Direction - Speed
Tuesday Afternoon - Tuesday Night SW 15 - 30
Wednesday - Wednesday Night SW 10 - 20
Mt. Rainier Direction - Speed
Tuesday Afternoon - Tuesday Night --- -
Wednesday - Wednesday Night --- -
Mt. Hood Direction - Speed
Tuesday Afternoon - Tuesday Night SW 15 - 30
Wednesday - Wednesday Night SW 15 - 25

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: 2:56 PM PST Tuesday, February 23, 2016

Extended Weather Synopsis for Saturday night through Saturday

The ridge should rebuild along the coast Wednesday night and Thursday with another bump in freezing levels across the PNW. Forecast models are in good agreement that the next Pacific frontal system will impact the area Friday night. This system looks to blow through the area quickly Friday night with showers quickly decreasing during the day on Saturday.  Snow levels should start out on the mild side and come down to around 4000 feet by Saturday morning.  

Extended Weather

Olympics, Washington Cascades and Mt. Hood
Thursday Night - Thursday Night

Partly to mostly clear. Mild. 

Friday

Increasing mid and high clouds. Chance of light rain and snow Olympics Friday afternoon. 

Friday Night

Light to occasionally moderate rain and snow becoming light to moderate showers. 

Saturday

Mostly cloudy with scattered light rain and snow showers in the morning decreasing in the afternoon with partial clearing. Cooler. 

Extended Snow/Freezing Levels

Mt. Baker Snoqualmie Pass Mt. Hood Easterly Flow *
Thursday - Friday Morning Freezing Level 7500' - 8500' 8000' - 9000' 9500' - 10500'
Friday Afternoon - Friday Evening Snow Level 6000' - 7000' 6500' - 7500' 7000' - 8000'
Friday Night - Saturday Snow Level 4000' - 5000' 4000' - 5000' 4500' - 5500'
Mt. Baker Elevation
Thursday - Friday Morning Freezing Level
7500' - 8500'
Friday Afternoon - Friday Evening Snow Level
6000' - 7000'
Friday Night - Saturday Snow Level
4000' - 5000'
Snoqualmie Pass Elevation
Thursday - Friday Morning Freezing Level
8000' - 9000'
Friday Afternoon - Friday Evening Snow Level
6500' - 7500'
Friday Night - Saturday Snow Level
4000' - 5000'
Mt. Hood Elevation
Thursday - Friday Morning Freezing Level
9500' - 10500'
Friday Afternoon - Friday Evening Snow Level
7000' - 8000'
Friday Night - Saturday Snow 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 Feb 23, 2016

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