Jump to: Weather Forecast I Snow/Freezing Level I Precipitation I Free Winds 5k I Free Winds 9k
Weather Synopsis for Tuesday & Tuesday
The Pacific Northwest will remain in cold northerly flow aloft for the next several days. Weak disturbances are expected to form on the downstream side of the ridge and progress from north to south over the next few days. These weak disturbances are likely to brush the forecast area at times, increasing cloud cover, and providing periods of light snow with no substantial accumulations.
A passing weak disturbance Tuesday has a weak surface low 300 miles off the coast of Washington on Tuesday morning. The disturbance should cause a period of light snow showers mainly from Mt Rainier south to Mt Hood and mainly during the afternoon and evening hours. Relatively more snow is expected at Mt Hood.
As of Wednesday morning, clouds from this weak disturbance are limiting night-time cooling in the Olympics and Central Cascades southward to Mt. Hood and the cloud extent is not expected to change markedly during the day. The clouds are keeping surface temperatures west of the Cascades slightly warmer than this time Monday morning. However, with clear skies and little to no wind, the northeast Cascades experienced their coldest temperatures of the season last night with a moderate inversion forming above 5500 feet. Mazama is in the ice box this morning at -8F Mazama with Washington Pass at -10F.
Precipitation from Tuesday's weak disturbance should end from north to south Tuesday night with skies clearing before midnight over the Olympics and north to central Cascades, and clearing after midnight in the south Cascades, and in the early morning hours for Mt. Hood.
High clouds will lower and thicken from northwest to southeast as a shortwave open trough approaches on Wednesday, arriving in the late afternoon and evening hours, bringing some light westerly flow out ahead of it. Light snow is likely to fall, mainly over the Olympics Tuesday night. Low-level flow will switch to N-NE Wednesday night as the shortwave trough passes to the south.
Weather Forecast
Olympics
| Tuesday | Cloudy with clearing in the late afternoon. |
| Tuesday Night | Clear and cold. |
| Wednesday | Clouds lowering and thickening. |
| Wednesday Night | Periods of light snow. |
Washington Cascades near and west of the Crest including Stevens, Snoqualmie and White Passes
| Tuesday | Periods of light snow developing, mainly from Mt. Rainier southward. Mid-to high clouds in the north and central part. |
| Tuesday Night | Skies becoming clear from north to south. |
| Wednesday | Clouds lowering and thickening. |
| Wednesday Night | Cloudy with a chance of snow flurries. |
East Slopes of the Washington Cascades
| Tuesday | Chance of very light snow southern part. Otherwise mainly mid-to high clouds. |
| Tuesday Night | Skies becoming clear from north to south. |
| Wednesday | Clear in the morning with clouds lowering and thickening. |
| Wednesday Night | Mostly cloudy. |
Mt. Hood
| Tuesday | Cloudy with periods of light snow developing in the afternoon. |
| Tuesday Night | Light snow decreasing after midnight with clearing possible by morning. |
| Wednesday | Mostly cloudy with mid to high-level clouds. |
| Wednesday Night | Cloudy with a chance of light snow after midnight. |
Issued: 7:37 AM PST Tuesday, February 20, 2018
Snow/Freezing Level (ft)
| Hurricane Ridge | Mt. Baker | Washington Pass | Leavenworth | Stevens Pass | Snoqualmie Pass | Mt. Rainier, Crystal & White Pass | Mt. Hood | ||
|---|---|---|---|---|---|---|---|---|---|
| Tuesday Morning | Snow Level * | 0' | 0' | 0' | ' | ' | 0' | ' | 0' |
| Tuesday Afternoon | Snow Level * | 0' | 0' | 0' | ' | ' | 0' | ' | 1000' |
| Tuesday Night | Snow Level * | 0' | 0' | 0' | ' | ' | 0' | ' | 0' |
| Wednesday Morning | Freezing Level * | 500' | 500' | 500' | ' | ' | 500' | ' | 500' |
| Wednesday Afternoon | Freezing Level | 500' | 500' | 500' | ' | ' | 500' | ' | 1000' |
| Wednesday Night | Snow Level * | 0' | 0' | 0' | ' | ' | 0' | ' | 0' |
| Hurricane Ridge | Elevation |
|---|---|
| Tuesday Morning |
Snow Level 0' (Easterly Flow *) |
| Tuesday Afternoon |
Snow Level 0' (Easterly Flow *) |
| Tuesday Night |
Snow Level 0' (Easterly Flow *) |
| Wednesday Morning |
Freezing Level 500' (Easterly Flow *) |
| Wednesday Afternoon |
Freezing Level 500' |
| Wednesday Night |
Snow Level 0' (Easterly Flow *) |
| Mt. Baker | Elevation |
|---|---|
| Tuesday Morning |
Snow Level 0' (Easterly Flow *) |
| Tuesday Afternoon |
Snow Level 0' (Easterly Flow *) |
| Tuesday Night |
Snow Level 0' (Easterly Flow *) |
| Wednesday Morning |
Freezing Level 500' (Easterly Flow *) |
| Wednesday Afternoon |
Freezing Level 500' |
| Wednesday Night |
Snow Level 0' (Easterly Flow *) |
| Washington Pass | Elevation |
|---|---|
| Tuesday Morning |
Snow Level 0' (Easterly Flow *) |
| Tuesday Afternoon |
Snow Level 0' (Easterly Flow *) |
| Tuesday Night |
Snow Level 0' (Easterly Flow *) |
| Wednesday Morning |
Freezing Level 500' (Easterly Flow *) |
| Wednesday Afternoon |
Freezing Level 500' |
| Wednesday Night |
Snow Level 0' (Easterly Flow *) |
| Leavenworth | Elevation |
|---|---|
| Tuesday Morning |
Snow Level ' (Easterly Flow *) |
| Tuesday Afternoon |
Snow Level ' (Easterly Flow *) |
| Tuesday Night |
Snow Level ' (Easterly Flow *) |
| Wednesday Morning |
Freezing Level ' (Easterly Flow *) |
| Wednesday Afternoon |
Freezing Level ' |
| Wednesday Night |
Snow Level ' (Easterly Flow *) |
| Stevens Pass | Elevation |
|---|---|
| Tuesday Morning |
Snow Level ' (Easterly Flow *) |
| Tuesday Afternoon |
Snow Level ' (Easterly Flow *) |
| Tuesday Night |
Snow Level ' (Easterly Flow *) |
| Wednesday Morning |
Freezing Level ' (Easterly Flow *) |
| Wednesday Afternoon |
Freezing Level ' |
| Wednesday Night |
Snow Level ' (Easterly Flow *) |
| Snoqualmie Pass | Elevation |
|---|---|
| Tuesday Morning |
Snow Level 0' (Easterly Flow *) |
| Tuesday Afternoon |
Snow Level 0' (Easterly Flow *) |
| Tuesday Night |
Snow Level 0' (Easterly Flow *) |
| Wednesday Morning |
Freezing Level 500' (Easterly Flow *) |
| Wednesday Afternoon |
Freezing Level 500' |
| Wednesday Night |
Snow Level 0' (Easterly Flow *) |
| Mt. Rainier & Crystal | Elevation |
|---|---|
| Tuesday Morning |
Snow Level ' (Easterly Flow *) |
| Tuesday Afternoon |
Snow Level ' (Easterly Flow *) |
| Tuesday Night |
Snow Level ' (Easterly Flow *) |
| Wednesday Morning |
Freezing Level ' (Easterly Flow *) |
| Wednesday Afternoon |
Freezing Level ' |
| Wednesday Night |
Snow Level ' (Easterly Flow *) |
| Mt. Hood | Elevation |
|---|---|
| Tuesday Morning |
Snow Level 0' (Easterly Flow *) |
| Tuesday Afternoon |
Snow Level 1000' (Easterly Flow *) |
| Tuesday Night |
Snow Level 0' (Easterly Flow *) |
| Wednesday Morning |
Freezing Level 500' (Easterly Flow *) |
| Wednesday Afternoon |
Freezing Level 1000' |
| Wednesday Night |
Snow Level 0' (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
| Tuesday | Tuesday | |
|---|---|---|
| Hurricane Ridge | LT 0.10 | LT 0.25 |
| 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 0.25 | LT 0.10 |
| White Pass | LT 0.25 | LT 0.10 |
| Mt Hood Meadows | LT 0.25 | LT 0.10 |
| Timberline | 0.25 - 0.50 | 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: 7:37 AM PST Tuesday, February 20, 2018
Free Winds at 5000' (mph)
| Hurricane Ridge | Mt. Baker | Stevens to Snoqualmie Pass | Mt. Rainier | Mt. Hood | |
|---|---|---|---|---|---|
| Tuesday Morning | E 5 - 15 | VAR 0 - 10 | ESE 5 - 15 | --- - | S 5 - 15 |
| Tuesday Afternoon | NE 5 - 15 | NNE 5 - 15 | VAR 0 - 10 | --- - | VAR 0 - 10 |
| Tuesday Night | NE 10 - 20 | NE 10 - 20 | E 5 - 15 | --- - | E 10 - 20 |
| Wednesday Morning | W 10 - 20 | SSW 5 - 15 | S 5 - 15 | --- - | ESE 5 - 15 |
| Wednesday Afternoon | W 5 - 15 | VAR 0 - 10 | W 5 - 15 | --- - | W 5 - 15 |
| Wednesday Night | NE 10 - 20 | NE 5 - 15 | VAR 0 - 10 | --- - | ENE 5 - 15 |
| Hurricane Ridge | Elevation |
|---|---|
| Tuesday Morning | E 5 - 15 |
| Tuesday Afternoon | NE 5 - 15 |
| Tuesday Night | NE 10 - 20 |
| Wednesday Morning | W 10 - 20 |
| Wednesday Afternoon | W 5 - 15 |
| Wednesday Night | NE 10 - 20 |
| Mt. Baker | Elevation |
|---|---|
| Tuesday Morning | VAR 0 - 10 |
| Tuesday Afternoon | NNE 5 - 15 |
| Tuesday Night | NE 10 - 20 |
| Wednesday Morning | SSW 5 - 15 |
| Wednesday Afternoon | VAR 0 - 10 |
| Wednesday Night | NE 5 - 15 |
| Stevens and Snoqualmie Pass | Elevation |
|---|---|
| Tuesday Morning | ESE 5 - 15 |
| Tuesday Afternoon | VAR 0 - 10 |
| Tuesday Night | E 5 - 15 |
| Wednesday Morning | S 5 - 15 |
| Wednesday Afternoon | W 5 - 15 |
| Wednesday Night | VAR 0 - 10 |
| Mt. Rainier | Elevation |
|---|---|
| Tuesday Morning | --- - |
| Tuesday Afternoon | --- - |
| Tuesday Night | --- - |
| Wednesday Morning | --- - |
| Wednesday Afternoon | --- - |
| Wednesday Night | --- - |
| Mt. Hood | Elevation |
|---|---|
| Tuesday Morning | S 5 - 15 |
| Tuesday Afternoon | VAR 0 - 10 |
| Tuesday Night | E 10 - 20 |
| Wednesday Morning | ESE 5 - 15 |
| Wednesday Afternoon | W 5 - 15 |
| Wednesday Night | ENE 5 - 15 |
| Hurricane Ridge | Direction - Speed |
|---|---|
| Tuesday Morning | E 5 - 15 |
| Tuesday Afternoon | NE 5 - 15 |
| Tuesday Night | NE 10 - 20 |
| Wednesday Morning | W 10 - 20 |
| Wednesday Afternoon | W 5 - 15 |
| Wednesday Night | NE 10 - 20 |
| Mt. Baker | Direction - Speed |
|---|---|
| Tuesday Morning | VAR 0 - 10 |
| Tuesday Afternoon | NNE 5 - 15 |
| Tuesday Night | NE 10 - 20 |
| Wednesday Morning | SSW 5 - 15 |
| Wednesday Afternoon | VAR 0 - 10 |
| Wednesday Night | NE 5 - 15 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Tuesday Morning | ESE 5 - 15 |
| Tuesday Afternoon | VAR 0 - 10 |
| Tuesday Night | E 5 - 15 |
| Wednesday Morning | S 5 - 15 |
| Wednesday Afternoon | W 5 - 15 |
| Wednesday Night | VAR 0 - 10 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Tuesday Morning | --- - |
| Tuesday Afternoon | --- - |
| Tuesday Night | --- - |
| Wednesday Morning | --- - |
| Wednesday Afternoon | --- - |
| Wednesday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| Tuesday Morning | S 5 - 15 |
| Tuesday Afternoon | VAR 0 - 10 |
| Tuesday Night | E 10 - 20 |
| Wednesday Morning | ESE 5 - 15 |
| Wednesday Afternoon | W 5 - 15 |
| Wednesday Night | ENE 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 Morning | NW 5 - 15 | WNW 5 - 15 | WNW 10 - 20 | --- - | WNW 20 - 30 |
| Tuesday Afternoon | N 5 - 15 | NW 5 - 15 | W 10 - 20 | --- - | W 20 - 30 |
| Tuesday Night | N 10 - 20 | NNW 10 - 20 | N 10 - 20 | --- - | WNW 15 - 25 |
| Wednesday Morning | W 10 - 20 | W 10 - 20 | W 15 - 25 | --- - | NW 10 - 20 |
| Wednesday Afternoon | W 5 - 15 | W 5 - 15 | W 15 - 25 | --- - | W 15 - 25 |
| Wednesday Night | NNE 20 - 30 | N 20 - 30 | N 15 - 25 | --- - | N 15 - 25 |
| Mt. Baker | Direction - Speed |
|---|---|
| Tuesday Morning | NW 5 - 15 |
| Tuesday Afternoon | N 5 - 15 |
| Tuesday Night | N 10 - 20 |
| Wednesday Morning | W 10 - 20 |
| Wednesday Afternoon | W 5 - 15 |
| Wednesday Night | NNE 20 - 30 |
| Washington Pass | Direction - Speed |
|---|---|
| Tuesday Morning | WNW 5 - 15 |
| Tuesday Afternoon | NW 5 - 15 |
| Tuesday Night | NNW 10 - 20 |
| Wednesday Morning | W 10 - 20 |
| Wednesday Afternoon | W 5 - 15 |
| Wednesday Night | N 20 - 30 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Tuesday Morning | WNW 10 - 20 |
| Tuesday Afternoon | W 10 - 20 |
| Tuesday Night | N 10 - 20 |
| Wednesday Morning | W 15 - 25 |
| Wednesday Afternoon | W 15 - 25 |
| Wednesday Night | N 15 - 25 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Tuesday Morning | --- - |
| Tuesday Afternoon | --- - |
| Tuesday Night | --- - |
| Wednesday Morning | --- - |
| Wednesday Afternoon | --- - |
| Wednesday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| Tuesday Morning | WNW 20 - 30 |
| Tuesday Afternoon | W 20 - 30 |
| Tuesday Night | WNW 15 - 25 |
| Wednesday Morning | NW 10 - 20 |
| Wednesday Afternoon | W 15 - 25 |
| Wednesday Night | N 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.
Jump to: Weather Forecast I Snow/Freezing Level I Precipitation I Free Winds 5k I Free Winds 9k
Previous forecast from Feb 18, 2018
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