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
Here comes another day of dry and mild conditions for the mountains of the Pacific Northwest. Change is in sight later this week...but not over the next two days. High freezing levels with temperatures inversions and low clouds in the Cascade Passes and along lower elevations of the east slopes Cascades will continue through the short term.
The caveat for today will be periods of high clouds affecting much of the area as a weak frontal system well to our north temporarily flattens the upper level ridge over the area. Offshore gradients will also weaken slightly today. The ridge axis will retrograde offshore Tuesday night and amplify offshore on Wednesday, helping temperatures increase once again as well as increasing offshore easterly gradients.
Weather Forecast
Olympics
| Tuesday |
Periods of high clouds. Mild. |
| Tuesday Night |
Periods of high clouds. Mild. |
| Wednesday |
Mostly sunny. Mild. |
| Wednesday Night |
Mostly clear. Mild. |
Washington Cascades near and west of the crest including Stevens, Snoqualmie, and White Passes
| Tuesday |
Mostly cloudy with high clouds. Mild except locally cooler with areas of low clouds Cascade Passes. |
| Tuesday Night |
Periods of high clouds. Mild except locally cooler with areas of low clouds Cascade Passes. |
| Wednesday |
Mostly sunny. Mild except locally cooler with areas of low clouds Cascade Passes. |
| Wednesday Night |
Mostly clear. Mild except locally cooler with areas of low clouds Cascade Passes. |
East slopes of the Washington Cascades
| Tuesday |
Mostly cloudy with high clouds. Mild higher elevations and cooler lower slopes with low clouds. |
| Tuesday Night |
Periods of high clouds. Mild higher elevations and cooler lower slopes with low clouds. |
| Wednesday |
Mostly sunny. Mild except locally cooler with areas of low clouds lower slopes. |
| Wednesday Night |
Mostly clear. Mild except locally cooler with areas of low clouds lower slopes. |
Mt. Hood Area
| Tuesday |
Mostly sunny with occasional high clouds. Mild. |
| Tuesday Night |
Mostly clear. Mild. |
| Wednesday |
Mostly sunny. Mild except locally cooler lower slopes. |
| Wednesday Night |
Mostly clear. Mild except locally cooler lower slopes. |
Issued: 2:12 PM PST Tuesday, December 12, 2017
Snow/Freezing Level (ft)
| Hurricane Ridge | Mt. Baker | Washington Pass | Leavenworth | Stevens Pass | Snoqualmie Pass | Mt. Rainier, Crystal & White Pass | Mt. Hood | ||
|---|---|---|---|---|---|---|---|---|---|
| Tuesday | Snow Level * | 8500' | 8000' | 7500' | ' | ' | 9500' | ' | 11500' |
| Tuesday Night | Snow Level * | 10000' | 9000' | 8000' | ' | ' | 10000' | ' | 12000' |
| Wednesday | Snow Level * | 12000' | 11000' | 11000' | ' | ' | 12000' | ' | 12500' |
| Wednesday Night | Snow Level * | 12000' | 11000' | 11000' | ' | ' | 12000' | ' | 12500' |
| Hurricane Ridge | Elevation |
|---|---|
| Tuesday |
Snow Level 8500' (Easterly Flow *) |
| Tuesday Night |
Snow Level 10000' (Easterly Flow *) |
| Wednesday |
Snow Level 12000' (Easterly Flow *) |
| Wednesday Night |
Snow Level 12000' (Easterly Flow *) |
| Mt. Baker | Elevation |
|---|---|
| Tuesday |
Snow Level 8000' (Easterly Flow *) |
| Tuesday Night |
Snow Level 9000' (Easterly Flow *) |
| Wednesday |
Snow Level 11000' (Easterly Flow *) |
| Wednesday Night |
Snow Level 11000' (Easterly Flow *) |
| Washington Pass | Elevation |
|---|---|
| Tuesday |
Snow Level 7500' (Easterly Flow *) |
| Tuesday Night |
Snow Level 8000' (Easterly Flow *) |
| Wednesday |
Snow Level 11000' (Easterly Flow *) |
| Wednesday Night |
Snow Level 11000' (Easterly Flow *) |
| Leavenworth | Elevation |
|---|---|
| Tuesday |
Snow Level ' (Easterly Flow *) |
| Tuesday Night |
Snow Level ' (Easterly Flow *) |
| Wednesday |
Snow Level ' (Easterly Flow *) |
| Wednesday Night |
Snow Level ' (Easterly Flow *) |
| Stevens Pass | Elevation |
|---|---|
| Tuesday |
Snow Level ' (Easterly Flow *) |
| Tuesday Night |
Snow Level ' (Easterly Flow *) |
| Wednesday |
Snow Level ' (Easterly Flow *) |
| Wednesday Night |
Snow Level ' (Easterly Flow *) |
| Snoqualmie Pass | Elevation |
|---|---|
| Tuesday |
Snow Level 9500' (Easterly Flow *) |
| Tuesday Night |
Snow Level 10000' (Easterly Flow *) |
| Wednesday |
Snow Level 12000' (Easterly Flow *) |
| Wednesday Night |
Snow Level 12000' (Easterly Flow *) |
| Mt. Rainier & Crystal | Elevation |
|---|---|
| Tuesday |
Snow Level ' (Easterly Flow *) |
| Tuesday Night |
Snow Level ' (Easterly Flow *) |
| Wednesday |
Snow Level ' (Easterly Flow *) |
| Wednesday Night |
Snow Level ' (Easterly Flow *) |
| Mt. Hood | Elevation |
|---|---|
| Tuesday |
Snow Level 11500' (Easterly Flow *) |
| Tuesday Night |
Snow Level 12000' (Easterly Flow *) |
| Wednesday |
Snow Level 12500' (Easterly Flow *) |
| Wednesday Night |
Snow Level 12500' (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 0.10 |
| 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: 2:12 PM PST Tuesday, December 12, 2017
Free Winds at 5000' (mph)
| Hurricane Ridge | Mt. Baker | Stevens to Snoqualmie Pass | Mt. Rainier | Mt. Hood | |
|---|---|---|---|---|---|
| Tuesday Afternoon | SW 0 - 10 | SW 0 - 10 | W 0 - 10 | --- - | W 5 - 15 |
| Tuesday Night | N 0 - 10 | N 0 - 10 | NW 0 - 10 | --- - | NW 0 - 10 |
| Wednesday Morning | NE 5 - 15 | NE 0 - 10 | E 0 - 10 | --- - | E 5 - 15 |
| Wednesday Afternoon | ENE 0 - 10 | NE 0 - 10 | E 5 - 15 | --- - | E 10 - 20 |
| Wednesday Night | S 0 - 10 | SE 0 - 10 | ESE 5 - 15 | --- - | ESE 10 - 20 |
| Hurricane Ridge | Elevation |
|---|---|
| Tuesday Afternoon | SW 0 - 10 |
| Tuesday Night | N 0 - 10 |
| Wednesday Morning | NE 5 - 15 |
| Wednesday Afternoon | ENE 0 - 10 |
| Wednesday Night | S 0 - 10 |
| Mt. Baker | Elevation |
|---|---|
| Tuesday Afternoon | SW 0 - 10 |
| Tuesday Night | N 0 - 10 |
| Wednesday Morning | NE 0 - 10 |
| Wednesday Afternoon | NE 0 - 10 |
| Wednesday Night | SE 0 - 10 |
| Stevens and Snoqualmie Pass | Elevation |
|---|---|
| Tuesday Afternoon | W 0 - 10 |
| Tuesday Night | NW 0 - 10 |
| Wednesday Morning | E 0 - 10 |
| Wednesday Afternoon | E 5 - 15 |
| Wednesday Night | ESE 5 - 15 |
| Mt. Rainier | Elevation |
|---|---|
| Tuesday Afternoon | --- - |
| Tuesday Night | --- - |
| Wednesday Morning | --- - |
| Wednesday Afternoon | --- - |
| Wednesday Night | --- - |
| Mt. Hood | Elevation |
|---|---|
| Tuesday Afternoon | W 5 - 15 |
| Tuesday Night | NW 0 - 10 |
| Wednesday Morning | E 5 - 15 |
| Wednesday Afternoon | E 10 - 20 |
| Wednesday Night | ESE 10 - 20 |
| Hurricane Ridge | Direction - Speed |
|---|---|
| Tuesday Afternoon | SW 0 - 10 |
| Tuesday Night | N 0 - 10 |
| Wednesday Morning | NE 5 - 15 |
| Wednesday Afternoon | ENE 0 - 10 |
| Wednesday Night | S 0 - 10 |
| Mt. Baker | Direction - Speed |
|---|---|
| Tuesday Afternoon | SW 0 - 10 |
| Tuesday Night | N 0 - 10 |
| Wednesday Morning | NE 0 - 10 |
| Wednesday Afternoon | NE 0 - 10 |
| Wednesday Night | SE 0 - 10 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Tuesday Afternoon | W 0 - 10 |
| Tuesday Night | NW 0 - 10 |
| Wednesday Morning | E 0 - 10 |
| Wednesday Afternoon | E 5 - 15 |
| Wednesday Night | ESE 5 - 15 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Tuesday Afternoon | --- - |
| Tuesday Night | --- - |
| Wednesday Morning | --- - |
| Wednesday Afternoon | --- - |
| Wednesday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| Tuesday Afternoon | W 5 - 15 |
| Tuesday Night | NW 0 - 10 |
| Wednesday Morning | E 5 - 15 |
| Wednesday Afternoon | E 10 - 20 |
| Wednesday Night | ESE 10 - 20 |
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 | WSW 10 - 20 | WSW 15 - 25 | WSW 20 - 30 | --- - | SW 20 - 30 |
| Tuesday Night | NW 10 - 20 | WNW 10 - 20 | WNW 20 - 30 | --- - | NW 15 - 25 |
| Wednesday Morning | N 10 - 20 | N 10 - 20 | N 15 - 25 | --- - | NW 10 - 20 |
| Wednesday Afternoon | N 0 - 10 | NNW 5 - 15 | NW 0 - 10 | --- - | N 0 - 10 |
| Wednesday Night | W 5 - 15 | WSW 5 - 15 | SW 5 - 15 | --- - | VAR 0 - 10 |
| Mt. Baker | Direction - Speed |
|---|---|
| Tuesday Afternoon | WSW 10 - 20 |
| Tuesday Night | NW 10 - 20 |
| Wednesday Morning | N 10 - 20 |
| Wednesday Afternoon | N 0 - 10 |
| Wednesday Night | W 5 - 15 |
| Washington Pass | Direction - Speed |
|---|---|
| Tuesday Afternoon | WSW 15 - 25 |
| Tuesday Night | WNW 10 - 20 |
| Wednesday Morning | N 10 - 20 |
| Wednesday Afternoon | NNW 5 - 15 |
| Wednesday Night | WSW 5 - 15 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Tuesday Afternoon | WSW 20 - 30 |
| Tuesday Night | WNW 20 - 30 |
| Wednesday Morning | N 15 - 25 |
| Wednesday Afternoon | NW 0 - 10 |
| Wednesday Night | SW 5 - 15 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Tuesday Afternoon | --- - |
| Tuesday Night | --- - |
| Wednesday Morning | --- - |
| Wednesday Afternoon | --- - |
| Wednesday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| Tuesday Afternoon | SW 20 - 30 |
| Tuesday Night | NW 15 - 25 |
| Wednesday Morning | NW 10 - 20 |
| Wednesday Afternoon | N 0 - 10 |
| Wednesday Night | VAR 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.
Issued: 2:12 PM PST Tuesday, December 12, 2017
Extended Weather Synopsis for Friday night through Friday
A fast moving Pacific frontal system will at least temporarily break down the upper level ridge that has dominated our recent weather, but not before we squeeze out one more very mild mid-December day on Thursday.
This frontal system does not look like it will bring heavy precipitation with it, but it should drastically lower snow levels from early Friday morning through late Friday afternoon with at least a few inches of snow accumulating along the west slopes of the Cascades and Olympics. Post-frontal westerlies should be blustery Friday and Friday night.
On Saturday, warm frontal moisture and clouds should periodically brush the area but may largely miss Mt. Hood as the upper level ridge tries to rebuild offshore, and in the process shunts the bulk of precipitation north.
Extended Weather
Olympics, Washington Cascades and Mt. Hood area
Partly to mostly sunny. Mild. Areas of low clouds Cascade Passes and lower elevations east slopes of the Cascades. Increasing clouds overnight.
Light rain and snow becoming light rain and snow showers mid-day, occasionally moderate west slopes of the Cascades. Brisk west winds. Cooling trend during the day. Becoming mostly cloudy with scattered light rain and snow showers Friday night.
Cloudy with periods of light rain and snow Washington Cascades. Mostly cloudy Mt. Hood area.
Extended Snow/Freezing Levels
| Mt. Baker | Snoqualmie Pass | Mt. Hood | Easterly Flow * | ||
|---|---|---|---|---|---|
| Thursday | Freezing Level | 10500' - 11500' | 12000' - 13000' | 12000' - 13000' | * |
| Thursday Night | Freezing Level | 6500' - 7500' | 8000' - 9000' | 10000' - 11000' | * |
| Friday Morning | Snow Level | 5000' - 6000' | 6000' - 7000' | 8000' - 9000' | |
| Friday Afternoon | Snow Level | 3000' - 4000' | 3000' - 4000' | 3000' - 4000' | |
| Friday Night | Snow Level | 2000' - 3000' | 2000' - 3000' | 2000' - 3000' | |
| Saturday | Snow Level | 2500' - 3500' | 2500' - 3500' | 3000' - 4000' |
| Mt. Baker | Elevation |
|---|---|
| Thursday |
Freezing Level 10500' - 11500' (Easterly Flow *) |
| Thursday Night |
Freezing Level 6500' - 7500' (Easterly Flow *) |
| Friday Morning |
Snow Level 5000' - 6000' |
| Friday Afternoon |
Snow Level 3000' - 4000' |
| Friday Night |
Snow Level 2000' - 3000' |
| Saturday |
Snow Level 2500' - 3500' |
| Snoqualmie Pass | Elevation |
|---|---|
| Thursday |
Freezing Level 12000' - 13000' (Easterly Flow *) |
| Thursday Night |
Freezing Level 8000' - 9000' (Easterly Flow *) |
| Friday Morning |
Snow Level 6000' - 7000' |
| Friday Afternoon |
Snow Level 3000' - 4000' |
| Friday Night |
Snow Level 2000' - 3000' |
| Saturday |
Snow Level 2500' - 3500' |
| Mt. Hood | Elevation |
|---|---|
| Thursday |
Freezing Level 12000' - 13000' (Easterly Flow *) |
| Thursday Night |
Freezing Level 10000' - 11000' (Easterly Flow *) |
| Friday Morning |
Snow Level 8000' - 9000' |
| Friday Afternoon |
Snow Level 3000' - 4000' |
| Friday Night |
Snow Level 2000' - 3000' |
| Saturday |
Snow Level 3000' - 4000' |
* 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 Dec 12, 2017
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