Jump to: Weather Forecast I Snow/Freezing Level I Precipitation I Free Winds 5k I Free Winds 9k I Extended Weather
Weather Synopsis for Saturday night through Sunday
High and mid clouds from an incoming frontal system are spreading inland this afternoon. Pre-frontal precipitation will quickly move over the area Saturday night. A trough digging south behind the N-S oriented frontal band will split the system on Sunday, directing some of the energy from the system into California. Light precipitation will fall across the region Saturday night and Sunday, except for locally heavier amounts expected over the Olympics and the Mt. Baker area. A period of southeasterly flow may also drive up snowfall totals locally for the Mission Ridge area Sunday.
Offshore easterly winds will continue to increase overnight through the Cascade Passes. Cool easterly flow will initially delay a transition from snow to rain Sunday. A modest warm-up with this pattern is expected to peak Sunday afternoon and evening. Generally windy conditions will develop in the alpine Saturday night and Sunday as the front weakens and stalls out over the area.
Showers will eventually taper down into Monday morning. There won't be much of a break in the weather, as a deep low pressure system headed into central British Colubia directs a moisture laden atmospheric river towards the Pacific Northwest late Monday afternoon.
Weather Forecast
Hurricane Ridge
| Saturday Night | Light to occasionally moderate rain and snow. Warming trend. Becoming windy. |
| Sunday | Moderate rain and snow. Mild. Windy. |
Mt. Baker
| Saturday Night | Light to occasionally moderate rain and snow. Becoming windy late. |
| Sunday | Moderate to occasionally heavy rain and snow. Warming trend. Windy. |
Washington Pass and Leavenworth
| Saturday Night | Light rain and snow developing overnight. |
| Sunday | Light rain and snow. Slow warming trend. Windy in the alpine. |
Stevens and Snoqualmie Pass
| Saturday Night | Periods of light rain and snow overnight. Moderate east winds at Pass level. |
| Sunday | Light to occasionally moderate rain and snow. Rain likely at Pass level Snoqualmie late morning, Stevens Pass in the afternoon. Slow warming trend. Moderate east winds at Pass level easing in the afternoon. |
Mt. Rainier, Crystal and White Pass
| Saturday Night | Light rain and snow developing overnight. |
| Sunday | Light to occasionally moderate rain and snow. Slow warming trend. Windy in the alpine. |
Mt. Hood
| Saturday Night | Periods of light rain and snow overnight. Warming trend. |
| Sunday | Light rain and snow. Mild. Windy in the alpine. |
Issued: 2:29 PM PST Saturday, December 15, 2018
Snow/Freezing Level (ft)
| Hurricane Ridge | Mt. Baker | Washington Pass | Leavenworth | Stevens Pass | Snoqualmie Pass | Mt. Rainier, Crystal & White Pass | Mt. Hood | ||
|---|---|---|---|---|---|---|---|---|---|
| Saturday Evening | Snow Level * | 3500' | 2500' | 2000' | 2000' | 2000' | 2500' | 3000' | 4500' |
| Saturday Night | Snow Level * | 5500' | 3000' | 2000' | 2000' | 2500' | 3000' | 4000' | 6500' |
| Sunday Morning | Snow Level * | 6500' | 4500' | 2000' | 2000' | 3000' | 3000' | 4500' | 7000' |
| Sunday Afternoon | Snow Level * | 6500' | 5000' | 3000' | 3500' | 4000' | 5000' | 6000' | 7000' |
| Sunday Evening | Snow Level | 5000' | 5000' | 4000' | 4500' | 5000' | 5500' | 5500' | 6000' |
| Sunday Night | Snow Level | 4000' | 4000' | 3500' | 4500' | 4000' | 4000' | 4500' | 4500' |
| Monday Morning | Snow Level | 4000' | 4000' | 3500' | 4000' | 4000' | 4000' | 4000' | 4000' |
| Monday Afternoon | Snow Level | 4500' | 4000' | 4000' | 4000' | 4000' | 4000' | 4000' | 5000' |
| Hurricane Ridge | Elevation |
|---|---|
| Saturday Evening |
Snow Level 3500' (Easterly Flow *) |
| Saturday Night |
Snow Level 5500' (Easterly Flow *) |
| Sunday Morning |
Snow Level 6500' (Easterly Flow *) |
| Sunday Afternoon |
Snow Level 6500' (Easterly Flow *) |
| Sunday Evening |
Snow Level 5000' |
| Sunday Night |
Snow Level 4000' |
| Monday Morning |
Snow Level 4000' |
| Monday Afternoon |
Snow Level 4500' |
| Mt. Baker | Elevation |
|---|---|
| Saturday Evening |
Snow Level 2500' (Easterly Flow *) |
| Saturday Night |
Snow Level 3000' (Easterly Flow *) |
| Sunday Morning |
Snow Level 4500' (Easterly Flow *) |
| Sunday Afternoon |
Snow Level 5000' (Easterly Flow *) |
| Sunday Evening |
Snow Level 5000' |
| Sunday Night |
Snow Level 4000' |
| Monday Morning |
Snow Level 4000' |
| Monday Afternoon |
Snow Level 4000' |
| Washington Pass | Elevation |
|---|---|
| Saturday Evening |
Snow Level 2000' (Easterly Flow *) |
| Saturday Night |
Snow Level 2000' (Easterly Flow *) |
| Sunday Morning |
Snow Level 2000' (Easterly Flow *) |
| Sunday Afternoon |
Snow Level 3000' (Easterly Flow *) |
| Sunday Evening |
Snow Level 4000' |
| Sunday Night |
Snow Level 3500' |
| Monday Morning |
Snow Level 3500' |
| Monday Afternoon |
Snow Level 4000' |
| Leavenworth | Elevation |
|---|---|
| Saturday Evening |
Snow Level 2000' (Easterly Flow *) |
| Saturday Night |
Snow Level 2000' (Easterly Flow *) |
| Sunday Morning |
Snow Level 2000' (Easterly Flow *) |
| Sunday Afternoon |
Snow Level 3500' (Easterly Flow *) |
| Sunday Evening |
Snow Level 4500' |
| Sunday Night |
Snow Level 4500' |
| Monday Morning |
Snow Level 4000' |
| Monday Afternoon |
Snow Level 4000' |
| Stevens Pass | Elevation |
|---|---|
| Saturday Evening |
Snow Level 2000' (Easterly Flow *) |
| Saturday Night |
Snow Level 2500' (Easterly Flow *) |
| Sunday Morning |
Snow Level 3000' (Easterly Flow *) |
| Sunday Afternoon |
Snow Level 4000' (Easterly Flow *) |
| Sunday Evening |
Snow Level 5000' |
| Sunday Night |
Snow Level 4000' |
| Monday Morning |
Snow Level 4000' |
| Monday Afternoon |
Snow Level 4000' |
| Snoqualmie Pass | Elevation |
|---|---|
| Saturday Evening |
Snow Level 2500' (Easterly Flow *) |
| Saturday Night |
Snow Level 3000' (Easterly Flow *) |
| Sunday Morning |
Snow Level 3000' (Easterly Flow *) |
| Sunday Afternoon |
Snow Level 5000' (Easterly Flow *) |
| Sunday Evening |
Snow Level 5500' |
| Sunday Night |
Snow Level 4000' |
| Monday Morning |
Snow Level 4000' |
| Monday Afternoon |
Snow Level 4000' |
| Mt. Rainier & Crystal | Elevation |
|---|---|
| Saturday Evening |
Snow Level 3000' (Easterly Flow *) |
| Saturday Night |
Snow Level 4000' (Easterly Flow *) |
| Sunday Morning |
Snow Level 4500' (Easterly Flow *) |
| Sunday Afternoon |
Snow Level 6000' (Easterly Flow *) |
| Sunday Evening |
Snow Level 5500' |
| Sunday Night |
Snow Level 4500' |
| Monday Morning |
Snow Level 4000' |
| Monday Afternoon |
Snow Level 4000' |
| Mt. Hood | Elevation |
|---|---|
| Saturday Evening |
Snow Level 4500' (Easterly Flow *) |
| Saturday Night |
Snow Level 6500' (Easterly Flow *) |
| Sunday Morning |
Snow Level 7000' (Easterly Flow *) |
| Sunday Afternoon |
Snow Level 7000' (Easterly Flow *) |
| Sunday Evening |
Snow Level 6000' |
| Sunday Night |
Snow Level 4500' |
| Monday Morning |
Snow Level 4000' |
| Monday Afternoon |
Snow Level 5000' |
* 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 Night | Sunday | Sunday Night | Sunday | |
|---|---|---|---|---|
| 4 pm - 4 am | 4 am - 4 pm | 4 pm - 4 am | 4 am - 4 pm | |
| Hurricane Ridge | 0.25 - 0.50 | 0.75 | 0.25 | 0.25 |
| Mt Baker Ski Area | 0.75 | 1.50 - 2.00 | 1.00 | 0.25 - 0.50 |
| Washington Pass | LT 0.10 | 0.25 - 0.50 | 0.25 - 0.50 | LT 0.10 |
| Leavenworth | LT 0.10 | 0.25 - 0.50 | LT 0.25 | 0 |
| Stevens Pass | LT 0.25 | 0.25 - 0.50 | 0.25 | LT 0.10 |
| Snoqualmie Pass | LT 0.25 | 0.25 - 0.50 | 0.25 - 0.50 | LT 0.10 |
| Mission Ridge | LT 0.10 | 0.50 - 0.75 | LT 0.25 | 0 |
| Crystal Mt | 0.25 | 0.25 - 0.50 | LT 0.25 | LT 0.10 |
| Paradise | 0.25 | 0.50 | 0.25 - 0.50 | LT 0.10 |
| White Pass | LT 0.10 | 0.25 - 0.50 | LT 0.25 | LT 0.10 |
| Mt Hood Meadows | LT 0.10 | 0.25 | LT 0.25 | LT 0.10 |
| Timberline | LT 0.25 | 0.25 | 0.25 | LT 0.10 |
| Hurricane Ridge | Precipitation Forecast |
|---|---|
| Saturday Night | 0.25 - 0.50 |
| Sunday | 0.75 |
| Sunday Night | 0.25 |
| Sunday | 0.25 |
| Mt Baker Ski Area | Precipitation Forecast |
|---|---|
| Saturday Night | 0.75 |
| Sunday | 1.50 - 2.00 |
| Sunday Night | 1.00 |
| Sunday | 0.25 - 0.50 |
| Washington Pass | Precipitation Forecast |
|---|---|
| Saturday Night | LT 0.10 |
| Sunday | 0.25 - 0.50 |
| Sunday Night | 0.25 - 0.50 |
| Sunday | LT 0.10 |
| Leavenworth | Precipitation Forecast |
|---|---|
| Saturday Night | LT 0.10 |
| Sunday | 0.25 - 0.50 |
| Sunday Night | LT 0.25 |
| Sunday | 0 |
| Stevens Pass | Precipitation Forecast |
|---|---|
| Saturday Night | LT 0.25 |
| Sunday | 0.25 - 0.50 |
| Sunday Night | 0.25 |
| Sunday | LT 0.10 |
| Snoqualmie Pass | Precipitation Forecast |
|---|---|
| Saturday Night | LT 0.25 |
| Sunday | 0.25 - 0.50 |
| Sunday Night | 0.25 - 0.50 |
| Sunday | LT 0.10 |
| Mission Ridge | Precipitation Forecast |
|---|---|
| Saturday Night | LT 0.10 |
| Sunday | 0.50 - 0.75 |
| Sunday Night | LT 0.25 |
| Sunday | 0 |
| Crystal Mt | Precipitation Forecast |
|---|---|
| Saturday Night | 0.25 |
| Sunday | 0.25 - 0.50 |
| Sunday Night | LT 0.25 |
| Sunday | LT 0.10 |
| Paradise | Precipitation Forecast |
|---|---|
| Saturday Night | 0.25 |
| Sunday | 0.50 |
| Sunday Night | 0.25 - 0.50 |
| Sunday | LT 0.10 |
| White Pass | Precipitation Forecast |
|---|---|
| Saturday Night | LT 0.10 |
| Sunday | 0.25 - 0.50 |
| Sunday Night | LT 0.25 |
| Sunday | LT 0.10 |
| Mt Hood Meadows | Precipitation Forecast |
|---|---|
| Saturday Night | LT 0.10 |
| Sunday | 0.25 |
| Sunday Night | LT 0.25 |
| Sunday | LT 0.10 |
| Timberline | Precipitation Forecast |
|---|---|
| Saturday Night | LT 0.25 |
| Sunday | 0.25 |
| Sunday Night | 0.25 |
| Sunday | 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: 2:29 PM PST Saturday, December 15, 2018
Free Winds at 5000' (mph)
| Hurricane Ridge | Mt. Baker | Stevens to Snoqualmie Pass | Mt. Rainier | Mt. Hood | |
|---|---|---|---|---|---|
| Saturday Evening | S 30 - 40 | SE 15 - 25 | ESE 15 - 25 | SE 15 - 25 | SE 10 - 20 |
| Saturday Night | S 30 - 40 | SE 20 - 35 | ESE 15 - 30 | SE 15 - 30 | SE 10 - 20 |
| Sunday Morning | S 35 - 45 | SE 20 - 35 | ESE 15 - 30 | SE 20 - 30 | SE 15 - 25 |
| Sunday Afternoon | S 20 - 30 | SE 15 - 25 | ESE 15 - 30 | SE 20 - 30 | SE 15 - 30 |
| Hurricane Ridge | Elevation |
|---|---|
| Saturday Evening | S 30 - 40 |
| Saturday Night | S 30 - 40 |
| Sunday Morning | S 35 - 45 |
| Sunday Afternoon | S 20 - 30 |
| Mt. Baker | Elevation |
|---|---|
| Saturday Evening | SE 15 - 25 |
| Saturday Night | SE 20 - 35 |
| Sunday Morning | SE 20 - 35 |
| Sunday Afternoon | SE 15 - 25 |
| Stevens and Snoqualmie Pass | Elevation |
|---|---|
| Saturday Evening | ESE 15 - 25 |
| Saturday Night | ESE 15 - 30 |
| Sunday Morning | ESE 15 - 30 |
| Sunday Afternoon | ESE 15 - 30 |
| Mt. Rainier | Elevation |
|---|---|
| Saturday Evening | SE 15 - 25 |
| Saturday Night | SE 15 - 30 |
| Sunday Morning | SE 20 - 30 |
| Sunday Afternoon | SE 20 - 30 |
| Mt. Hood | Elevation |
|---|---|
| Saturday Evening | SE 10 - 20 |
| Saturday Night | SE 10 - 20 |
| Sunday Morning | SE 15 - 25 |
| Sunday Afternoon | SE 15 - 30 |
| Hurricane Ridge | Direction - Speed |
|---|---|
| Saturday Evening | S 30 - 40 |
| Saturday Night | S 30 - 40 |
| Sunday Morning | S 35 - 45 |
| Sunday Afternoon | S 20 - 30 |
| Mt. Baker | Direction - Speed |
|---|---|
| Saturday Evening | SE 15 - 25 |
| Saturday Night | SE 20 - 35 |
| Sunday Morning | SE 20 - 35 |
| Sunday Afternoon | SE 15 - 25 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Saturday Evening | ESE 15 - 25 |
| Saturday Night | ESE 15 - 30 |
| Sunday Morning | ESE 15 - 30 |
| Sunday Afternoon | ESE 15 - 30 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Saturday Evening | SE 15 - 25 |
| Saturday Night | SE 15 - 30 |
| Sunday Morning | SE 20 - 30 |
| Sunday Afternoon | SE 20 - 30 |
| Mt. Hood | Direction - Speed |
|---|---|
| Saturday Evening | SE 10 - 20 |
| Saturday Night | SE 10 - 20 |
| Sunday Morning | SE 15 - 25 |
| Sunday Afternoon | SE 15 - 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 | |
|---|---|---|---|---|---|
| Saturday Evening | SSW 35 - 45 | SSW 25 - 35 | SW 40 - 50 | SW 45 - 55 | SW 45 - 55 |
| Saturday Night | S 50 - 60 | SSW 35 - 45 | SW 50 - 60 | SW 50 - 60 | SW 50 - 60 |
| Sunday Morning | S 50 - 60 | S 35 - 45 | SW 50 - 60 | SSW 50 - 60 | SW 50 - 60 |
| Sunday Afternoon | SSW 45 - 55 | SSW 30 - 40 | SW 50 - 60 | SW 50 - 60 | SW 50 - 60 |
| Mt. Baker | Direction - Speed |
|---|---|
| Saturday Evening | SSW 35 - 45 |
| Saturday Night | S 50 - 60 |
| Sunday Morning | S 50 - 60 |
| Sunday Afternoon | SSW 45 - 55 |
| Washington Pass | Direction - Speed |
|---|---|
| Saturday Evening | SSW 25 - 35 |
| Saturday Night | SSW 35 - 45 |
| Sunday Morning | S 35 - 45 |
| Sunday Afternoon | SSW 30 - 40 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Saturday Evening | SW 40 - 50 |
| Saturday Night | SW 50 - 60 |
| Sunday Morning | SW 50 - 60 |
| Sunday Afternoon | SW 50 - 60 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Saturday Evening | SW 45 - 55 |
| Saturday Night | SW 50 - 60 |
| Sunday Morning | SSW 50 - 60 |
| Sunday Afternoon | SW 50 - 60 |
| Mt. Hood | Direction - Speed |
|---|---|
| Saturday Evening | SW 45 - 55 |
| Saturday Night | SW 50 - 60 |
| Sunday Morning | SW 50 - 60 |
| Sunday Afternoon | SW 50 - 60 |
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: 2:29 PM PST Saturday, December 15, 2018
Extended Weather Synopsis for Sunday night through Sunday
Heavy precipitation will spread over the area Monday night with snow levels on the rise. Easterly flow will once again slow warming in the Passes, but a change to rain is expected for most areas by early Tuesday morning. The initial frontal boundary will pass late Monday night, but strong westerly flow and additional waves of moisture will keep the tap turned on during the day Tuesday with generally mild snow levels.
Showers will diminish Wednesday night into Thursday morning as strong upper level ridging quickly builds along the West Coast. However, a developing low pressure system well offshore may spread warm frontal precipitation over the area as it lifts north Thursday afternoon.
Extended Snow/Freezing Levels
| Mt. Baker | Snoqualmie Pass | Mt. Hood | Easterly Flow * | ||
|---|---|---|---|---|---|
| Monday Night | Snow Level | 3500' - 4500' | 3000' - 5000' | 6500' - 7500' | * |
| Tuesday | Snow Level | 4500' - 5500' | 5500' - 6500' | 6500' - 7500' | |
| Tuesday Night | Snow Level | 3500' - 4500' | 3500' - 4500' | 4500' - 5500' | |
| Wednesday | Snow Level | 2500' - 3500' | 3000' - 4000' | 4500' - 5500' |
| Mt. Baker | Elevation |
|---|---|
| Monday Night |
Snow Level 3500' - 4500' (Easterly Flow *) |
| Tuesday |
Snow Level 4500' - 5500' |
| Tuesday Night |
Snow Level 3500' - 4500' |
| Wednesday |
Snow Level 2500' - 3500' |
| Snoqualmie Pass | Elevation |
|---|---|
| Monday Night |
Snow Level 3000' - 5000' (Easterly Flow *) |
| Tuesday |
Snow Level 5500' - 6500' |
| Tuesday Night |
Snow Level 3500' - 4500' |
| Wednesday |
Snow Level 3000' - 4000' |
| Mt. Hood | Elevation |
|---|---|
| Monday Night |
Snow Level 6500' - 7500' (Easterly Flow *) |
| Tuesday |
Snow Level 6500' - 7500' |
| Tuesday Night |
Snow Level 4500' - 5500' |
| Wednesday |
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 Dec 15, 2018
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