Jump to: Weather Forecast I Snow/Freezing Level I Precipitation I Free Winds 5k I Free Winds 9k I Extended Weather
Weather Synopsis for Monday & Friday
A low pressure system located off the central Oregon coast earlier this morning is tracking NE across the southern Washington Cascades today. The precipitation shield associated with a warm front has spread north into the central Washington Cascades through mid-day, but continues to only lightly brush the Olympics and north Cascades.
Precipitation, winds and a warming trend will be most significant in the Mt. Hood area and south Washington Cascades on Monday although all areas are seeing a slight bump in snow levels. Mt. Hood may see snow levels bump up to 5000-5500 ft by late morning while they are in the warm sector before they slowly start to cool this afternoon. A switch to westerly winds will occur everywhere as the low passes to the east side of the Cascades this afternoon.
Showers should ease later tonight before another low pressure system develops off the Oregon Coast and tracks to the NE on Tuesday. Most forecast models have this low tracking further south and mainly affecting Mt. Hood. However, the European model moves the precipitation shield further north, similar to Monday's system. The Day 2 precipitation forecast reflects the GFS/WRF track for now.
A cold upper level trough is forecast to move over PNW starting Tuesday afternoon and snow levels should begin to drop in earnest later Tuesday afternoon into Tuesday night with light snow showers continuing overnight.
Weather Forecast
Olympics
| Monday |
Periods of light rain and snow developing in the morning becoming light rain and snow showers in the afternoon. Slight warming trend peaking in the early afternoon. |
| Monday Night |
Mostly cloudy with scattered light showers. |
| Tuesday |
Cloudy with ceilings lowering in the afternoon. Periods of very light rain and snow developing mid-day. |
| Tuesday Night |
Mostly cloudy with light rain and snow showers. Cooling trend. |
Washington Cascades near and west of the crest including Stevens, Snoqualmie, and White Passes
| Monday Afternoon - Monday Evening |
Moderate rain and snow south Cascades. Light to occasionally moderate rain and snow in the central Cascades. Periods of light snow in the north Cascades. All steady precipitation becoming showers in the afternoon. Slight warming trend peaking in the afternoon. Strong alpine winds south Washington Cascades. |
| Monday Night |
Mostly cloudy with scattered light showers. |
| Tuesday |
Cloudy with ceilings lowering in the afternoon. Periods of light rain and snow developing mid-day, mainly central and south Cascades. |
| Tuesday Night |
Mostly cloudy with light rain and snow showers. Cooling trend. |
East slopes of the Washington Cascades
| Monday Afternoon - Monday Evening |
Light to moderate rain and snow southeast and central-east Cascades becoming showers in the afternoon. Light rain northeast Cascades becoming showers in the afternoon. Slight warming trend peaking in the afternoon. Strong alpine winds southeast Washington Cascades. |
| Monday Night |
Mostly cloudy with isolated light showers. |
| Tuesday |
Cloudy with ceilings lowering in the afternoon. Periods of light rain and snow developing mid-day, mainly central-east and southeast Cascades. |
| Tuesday Night |
Mostly cloudy with scattered light rain and snow showers. Cooling trend. |
Mt. Hood Area
| Monday Afternoon - Monday Evening |
Light to moderate rain and snow becoming showers in the afternoon. Strong alpine winds. |
| Monday Night |
Mostly cloudy with scattered light showers. |
| Tuesday |
Light to occasionally moderate rain and snow. |
| Tuesday Night |
Mostly cloudy with light rain and snow showers. Cooling trend. |
Issued: 2:18 PM PST Monday, February 20, 2017
Snow/Freezing Level (ft)
| Hurricane Ridge | Mt. Baker | Washington Pass | Leavenworth | Stevens Pass | Snoqualmie Pass | Mt. Rainier, Crystal & White Pass | Mt. Hood | ||
|---|---|---|---|---|---|---|---|---|---|
| Monday Afternoon | Snow Level | 4500' | 4000' | 4000' | ' | ' | 3500' | ' | 4500' |
| Monday Night - Tuesday Morning | Snow Level | 2500' | 2000' | 1500' | ' | ' | 2500' | ' | 4000' |
| Tuesday Afternoon | Snow Level | 3000' | 2500' | 3500' | ' | ' | 3000' | ' | 3500' |
| Tuesday Night | Snow Level | 1000' | 1000' | 500' | ' | ' | 1000' | ' | 1500' |
| Hurricane Ridge | Elevation |
|---|---|
| Monday Afternoon |
Snow Level 4500' |
| Monday Night - Tuesday Morning |
Snow Level 2500' |
| Tuesday Afternoon |
Snow Level 3000' |
| Tuesday Night |
Snow Level 1000' |
| Mt. Baker | Elevation |
|---|---|
| Monday Afternoon |
Snow Level 4000' |
| Monday Night - Tuesday Morning |
Snow Level 2000' |
| Tuesday Afternoon |
Snow Level 2500' |
| Tuesday Night |
Snow Level 1000' |
| Washington Pass | Elevation |
|---|---|
| Monday Afternoon |
Snow Level 4000' |
| Monday Night - Tuesday Morning |
Snow Level 1500' |
| Tuesday Afternoon |
Snow Level 3500' |
| Tuesday Night |
Snow Level 500' |
| Leavenworth | Elevation |
|---|---|
| Monday Afternoon |
Snow Level ' |
| Monday Night - Tuesday Morning |
Snow Level ' |
| Tuesday Afternoon |
Snow Level ' |
| Tuesday Night |
Snow Level ' |
| Stevens Pass | Elevation |
|---|---|
| Monday Afternoon |
Snow Level ' |
| Monday Night - Tuesday Morning |
Snow Level ' |
| Tuesday Afternoon |
Snow Level ' |
| Tuesday Night |
Snow Level ' |
| Snoqualmie Pass | Elevation |
|---|---|
| Monday Afternoon |
Snow Level 3500' |
| Monday Night - Tuesday Morning |
Snow Level 2500' |
| Tuesday Afternoon |
Snow Level 3000' |
| Tuesday Night |
Snow Level 1000' |
| Mt. Rainier & Crystal | Elevation |
|---|---|
| Monday Afternoon |
Snow Level ' |
| Monday Night - Tuesday Morning |
Snow Level ' |
| Tuesday Afternoon |
Snow Level ' |
| Tuesday Night |
Snow Level ' |
| Mt. Hood | Elevation |
|---|---|
| Monday Afternoon |
Snow Level 4500' |
| Monday Night - Tuesday Morning |
Snow Level 4000' |
| Tuesday Afternoon |
Snow Level 3500' |
| Tuesday Night |
Snow Level 1500' |
* 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 0.25 | LT 0.10 |
| Washington Pass | LT 0.25 | LT 0.10 |
| Stevens Pass | 0 - 0.50 | LT 0.10 |
| Snoqualmie Pass | 0.50 - 0.75 | LT 0.10 |
| Mission Ridge | 0.25 - 0.50 | LT 0.10 |
| Crystal Mt | 0 - 0.75 | LT 0.10 |
| Paradise | 0 - 1.00 | LT 0.10 |
| White Pass | 0.75 - 1.00 | LT 0.10 |
| Mt Hood Meadows | 0 - 1.00 | 0.50 - 0.75 |
| Timberline | 1.00 - 1.50 | 0 - 0.75 |
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: 2:18 PM PST Monday, February 20, 2017
Free Winds at 5000' (mph)
| Hurricane Ridge | Mt. Baker | Stevens to Snoqualmie Pass | Mt. Rainier | Mt. Hood | |
|---|---|---|---|---|---|
| Monday Afternoon | W 5 - 15 | W 0 - 10 | W 5 - 15 | --- - | WSW 25 - 40 |
| Monday Night - Tuesday Morning | N 0 - 10 | VAR 0 - 10 | VAR 0 - 10 | --- - | E 0 - 10 |
| Tuesday Afternoon - Tuesday Night | NW 10 - 20 | W 5 - 15 | WNW 5 - 15 | --- - | NW 20 - 30 |
| Hurricane Ridge | Elevation |
|---|---|
| Monday Afternoon | W 5 - 15 |
| Monday Night - Tuesday Morning | N 0 - 10 |
| Tuesday Afternoon - Tuesday Night | NW 10 - 20 |
| Mt. Baker | Elevation |
|---|---|
| Monday Afternoon | W 0 - 10 |
| Monday Night - Tuesday Morning | VAR 0 - 10 |
| Tuesday Afternoon - Tuesday Night | W 5 - 15 |
| Stevens and Snoqualmie Pass | Elevation |
|---|---|
| Monday Afternoon | W 5 - 15 |
| Monday Night - Tuesday Morning | VAR 0 - 10 |
| Tuesday Afternoon - Tuesday Night | WNW 5 - 15 |
| Mt. Rainier | Elevation |
|---|---|
| Monday Afternoon | --- - |
| Monday Night - Tuesday Morning | --- - |
| Tuesday Afternoon - Tuesday Night | --- - |
| Mt. Hood | Elevation |
|---|---|
| Monday Afternoon | WSW 25 - 40 |
| Monday Night - Tuesday Morning | E 0 - 10 |
| Tuesday Afternoon - Tuesday Night | NW 20 - 30 |
| Hurricane Ridge | Direction - Speed |
|---|---|
| Monday Afternoon | W 5 - 15 |
| Monday Night - Tuesday Morning | N 0 - 10 |
| Tuesday Afternoon - Tuesday Night | NW 10 - 20 |
| Mt. Baker | Direction - Speed |
|---|---|
| Monday Afternoon | W 0 - 10 |
| Monday Night - Tuesday Morning | VAR 0 - 10 |
| Tuesday Afternoon - Tuesday Night | W 5 - 15 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Monday Afternoon | W 5 - 15 |
| Monday Night - Tuesday Morning | VAR 0 - 10 |
| Tuesday Afternoon - Tuesday Night | WNW 5 - 15 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Monday Afternoon | --- - |
| Monday Night - Tuesday Morning | --- - |
| Tuesday Afternoon - Tuesday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| Monday Afternoon | WSW 25 - 40 |
| Monday Night - Tuesday Morning | E 0 - 10 |
| Tuesday Afternoon - Tuesday Night | NW 20 - 30 |
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 | |
|---|---|---|---|---|---|
| Monday Afternoon | W 10 - 20 | W 10 - 20 | WSW 25 - 35 | --- - | SW 50 - 70 |
| Monday Night - Tuesday Morning | SW 10 - 20 | SW 0 - 10 | SW 5 - 15 | --- - | SSW 10 - 20 |
| Tuesday Afternoon | W 10 - 20 | W 5 - 15 | NW 15 - 25 | --- - | NW 25 - 35 |
| Tuesday Night | W 15 - 25 | W 20 - 30 | W 25 - 35 | --- - | W 30 - 40 |
| Mt. Baker | Direction - Speed |
|---|---|
| Monday Afternoon | W 10 - 20 |
| Monday Night - Tuesday Morning | SW 10 - 20 |
| Tuesday Afternoon | W 10 - 20 |
| Tuesday Night | W 15 - 25 |
| Washington Pass | Direction - Speed |
|---|---|
| Monday Afternoon | W 10 - 20 |
| Monday Night - Tuesday Morning | SW 0 - 10 |
| Tuesday Afternoon | W 5 - 15 |
| Tuesday Night | W 20 - 30 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Monday Afternoon | WSW 25 - 35 |
| Monday Night - Tuesday Morning | SW 5 - 15 |
| Tuesday Afternoon | NW 15 - 25 |
| Tuesday Night | W 25 - 35 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Monday Afternoon | --- - |
| Monday Night - Tuesday Morning | --- - |
| Tuesday Afternoon | --- - |
| Tuesday Night | --- - |
| Mt. Hood | Direction - Speed |
|---|---|
| Monday Afternoon | SW 50 - 70 |
| Monday Night - Tuesday Morning | SSW 10 - 20 |
| Tuesday Afternoon | NW 25 - 35 |
| Tuesday Night | W 30 - 40 |
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: 2:18 PM PST Monday, February 20, 2017
Extended Weather Synopsis for Friday night through Friday
A cold upper level trough will settle over the Pacific Northwest Wednesday and Thursday. The air mass will be marginally unstable on Wednesday. While precipitation amounts don't look overly impressive, heavier convective showers are possible in the afternoon. On Thursday, showers should be more isolated in nature and increase slightly in the afternoon with day-time warming. By Friday, an upper level low tracking south in the northerly branch of the jet stream should dig off the Washington coast. Shower activity is more likely for the Olympics, closer to the upper low with less clouds and shower coverage over the Cascades. Snow levels will remain low through the extended.
Extended Weather
Olympics, Washington Cascades and Mt. Hood
Cloudy with light snow showers. Showers may become occasionally moderate in the afternoon. Colder.
Partly to mostly cloudy with isolated snow showers mainly in the afternoon.
Mostly cloudy with scattered light snow showers Olympics. Partly sunny with isolated light snow showers elsewhere.
Extended Snow/Freezing Levels
| Mt. Baker | Snoqualmie Pass | Mt. Hood | Easterly Flow * | ||
|---|---|---|---|---|---|
| Wednesday | Snow Level | 1000' - 2000' | 1000' - 2000' | 1500' - 2500' | |
| Wednesday Night - Friday | Snow Level | 500' - 1500' | 500' - 1500' | 500' - 1500' |
| Mt. Baker | Elevation |
|---|---|
| Wednesday |
Snow Level 1000' - 2000' |
| Wednesday Night - Friday |
Snow Level 500' - 1500' |
| Snoqualmie Pass | Elevation |
|---|---|
| Wednesday |
Snow Level 1000' - 2000' |
| Wednesday Night - Friday |
Snow Level 500' - 1500' |
| Mt. Hood | Elevation |
|---|---|
| Wednesday |
Snow Level 1500' - 2500' |
| Wednesday Night - Friday |
Snow Level 500' - 1500' |
* 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 20, 2017
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