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 night through Tuesday
A very stormy weather pattern continues...
A strong jet aimed for Oregon chases a departed winter storm Tuesday night. Strong W-SW winds (strongest south of I-90) continue. Moderate post-frontal rain and snow showers will bring significant accumulations above 3500 ft. The atmosphere will be unstable, so expect locally intense snowfall. This pattern will continue Wednesday, but showers will become more sporadic and lighter, ending from south to north as the flow shifts to the SW by afternoon.
A warm front will lift across the region Wednesday evening, warming temperatures above the freezing mark at 5000 ft in most locations with some limited cold air holding on in sheltered valley locations of the NE Cascades. Light snow changing to rain toward morning is expected in the central Cascade Pass locations.
On Thursday, the associated and intensifying low pressure will make landfall on Vancouver Island, dragging a sharp cold front and sharp temperature decreases across the forecast area from west to east. Strong winds will be a greater story than precipitation with this storm, although >1" can be expected for Hurricane Ridge, the North Cascades, and Rainier areas from Wednesday evening through Thursday.
Weather Forecast
Hurricane Ridge
| Tuesday Night | Light to moderate snow showers in a slightly cool, unstable air mass. Moderate to strong winds. |
| Wednesday | Light snow showers decreasing in the morning. SW wind shifting to southerly late in the day as light snow re-develops. |
Mt. Baker
| Tuesday Night | Moderate post-frontal snow showers, heavy at times. Moderate wind gusting strong. |
| Wednesday | Decreasing light snow showers. Decreasing winds becoming light to moderate and shifting southerly. |
Washington Pass and Leavenworth
| Tuesday Night | Light post-frontal snow (and low elevation rain) showers, heavier in convective cells. Moderate wind gusting strong. |
| Wednesday | Decreasing light snow showers with sun breaking out at times. Winds shifting SE with clouds increasing in the afternoon. |
Stevens and Snoqualmie Pass
| Tuesday Night | Moderate snow showers. Moderate to strong winds. |
| Wednesday | Light to moderate snow showers, decreasing. Decreasing winds becoming southerly. |
Mt. Rainier, Crystal and White Pass
| Tuesday Night | Moderate to heavy snow Paradise; moderate snow showers at White Pass; and light snow showers under partially blocked flow at Crystal. Moderate to strong winds. |
| Wednesday | Light to moderate snow rapidly decreasing and ending in the morning. Decreasing winds become southerly. |
Mt. Hood
| Tuesday Night | Moderate snow showers. Strong winds. |
| Wednesday | Very light snow at times. Moderate winds decreasing and becoming light, southeasterly. |
Issued: 2:47 PM PST Tuesday, December 18, 2018
Snow/Freezing Level (ft)
| Hurricane Ridge | Mt. Baker | Washington Pass | Leavenworth | Stevens Pass | Snoqualmie Pass | Mt. Rainier, Crystal & White Pass | Mt. Hood | ||
|---|---|---|---|---|---|---|---|---|---|
| Tuesday Evening | Snow Level | 3500' | 3000' | 3500' | 3500' | 3500' | 3500' | 3500' | 4500' |
| Tuesday Night | Snow Level | 3500' | 3000' | 3000' | 3500' | 3000' | 3000' | 3500' | 4000' |
| Wednesday Morning | Snow Level | 3000' | 3000' | 2500' | 3500' | 3000' | 3000' | 3500' | 3500' |
| Wednesday Afternoon | Snow Level | 3500' | 3000' | 3000' | 3500' | 3500' | 3500' | 3500' | 4000' |
| Wednesday Evening | Snow Level * | 6000' | 3500' | 3000' | 3500' | 3500' | 5500' | 6000' | 7000' |
| Wednesday Night | Snow Level * | 7500' | 5500' | 3500' | 4500' | 5000' | 6500' | 6500' | 7500' |
| Thursday Morning | Snow Level * | 5000' | 5000' | 4000' | 4500' | 4500' | 5000' | 5000' | 6000' |
| Thursday Afternoon | Snow Level | 2000' | 3500' | 3500' | 3000' | 2500' | 2500' | 2500' | 3000' |
| Hurricane Ridge | Elevation |
|---|---|
| Tuesday Evening |
Snow Level 3500' |
| Tuesday Night |
Snow Level 3500' |
| Wednesday Morning |
Snow Level 3000' |
| Wednesday Afternoon |
Snow Level 3500' |
| Wednesday Evening |
Snow Level 6000' (Easterly Flow *) |
| Wednesday Night |
Snow Level 7500' (Easterly Flow *) |
| Thursday Morning |
Snow Level 5000' (Easterly Flow *) |
| Thursday Afternoon |
Snow Level 2000' |
| Mt. Baker | Elevation |
|---|---|
| Tuesday Evening |
Snow Level 3000' |
| Tuesday Night |
Snow Level 3000' |
| Wednesday Morning |
Snow Level 3000' |
| Wednesday Afternoon |
Snow Level 3000' |
| Wednesday Evening |
Snow Level 3500' (Easterly Flow *) |
| Wednesday Night |
Snow Level 5500' (Easterly Flow *) |
| Thursday Morning |
Snow Level 5000' (Easterly Flow *) |
| Thursday Afternoon |
Snow Level 3500' |
| Washington Pass | Elevation |
|---|---|
| Tuesday Evening |
Snow Level 3500' |
| Tuesday Night |
Snow Level 3000' |
| Wednesday Morning |
Snow Level 2500' |
| Wednesday Afternoon |
Snow Level 3000' |
| Wednesday Evening |
Snow Level 3000' (Easterly Flow *) |
| Wednesday Night |
Snow Level 3500' (Easterly Flow *) |
| Thursday Morning |
Snow Level 4000' (Easterly Flow *) |
| Thursday Afternoon |
Snow Level 3500' |
| Leavenworth | Elevation |
|---|---|
| Tuesday Evening |
Snow Level 3500' |
| Tuesday Night |
Snow Level 3500' |
| Wednesday Morning |
Snow Level 3500' |
| Wednesday Afternoon |
Snow Level 3500' |
| Wednesday Evening |
Snow Level 3500' (Easterly Flow *) |
| Wednesday Night |
Snow Level 4500' (Easterly Flow *) |
| Thursday Morning |
Snow Level 4500' (Easterly Flow *) |
| Thursday Afternoon |
Snow Level 3000' |
| Stevens Pass | Elevation |
|---|---|
| Tuesday Evening |
Snow Level 3500' |
| Tuesday Night |
Snow Level 3000' |
| Wednesday Morning |
Snow Level 3000' |
| Wednesday Afternoon |
Snow Level 3500' |
| Wednesday Evening |
Snow Level 3500' (Easterly Flow *) |
| Wednesday Night |
Snow Level 5000' (Easterly Flow *) |
| Thursday Morning |
Snow Level 4500' (Easterly Flow *) |
| Thursday Afternoon |
Snow Level 2500' |
| Snoqualmie Pass | Elevation |
|---|---|
| Tuesday Evening |
Snow Level 3500' |
| Tuesday Night |
Snow Level 3000' |
| Wednesday Morning |
Snow Level 3000' |
| Wednesday Afternoon |
Snow Level 3500' |
| Wednesday Evening |
Snow Level 5500' (Easterly Flow *) |
| Wednesday Night |
Snow Level 6500' (Easterly Flow *) |
| Thursday Morning |
Snow Level 5000' (Easterly Flow *) |
| Thursday Afternoon |
Snow Level 2500' |
| Mt. Rainier & Crystal | Elevation |
|---|---|
| Tuesday Evening |
Snow Level 3500' |
| Tuesday Night |
Snow Level 3500' |
| Wednesday Morning |
Snow Level 3500' |
| Wednesday Afternoon |
Snow Level 3500' |
| Wednesday Evening |
Snow Level 6000' (Easterly Flow *) |
| Wednesday Night |
Snow Level 6500' (Easterly Flow *) |
| Thursday Morning |
Snow Level 5000' (Easterly Flow *) |
| Thursday Afternoon |
Snow Level 2500' |
| Mt. Hood | Elevation |
|---|---|
| Tuesday Evening |
Snow Level 4500' |
| Tuesday Night |
Snow Level 4000' |
| Wednesday Morning |
Snow Level 3500' |
| Wednesday Afternoon |
Snow Level 4000' |
| Wednesday Evening |
Snow Level 7000' (Easterly Flow *) |
| Wednesday Night |
Snow Level 7500' (Easterly Flow *) |
| Thursday Morning |
Snow Level 6000' (Easterly Flow *) |
| Thursday Afternoon |
Snow Level 3000' |
* 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 Night | Tuesday | Tuesday Night | Tuesday | |
|---|---|---|---|---|
| 4 pm - 4 am | 4 am - 4 pm | 4 pm - 4 am | 4 am - 4 pm | |
| Hurricane Ridge | 0.25 - 0.50 | LT 0.10 | 0.50 - 0.75 | 0.75 -1.00 |
| Mt Baker Ski Area | 0.50 - 0.75 | 0.25 | 1.00 - 1.50 | 2.00 |
| Washington Pass | 0.25 | 0.25 | 0.50 | 0.75 -1.00 |
| Leavenworth | 0.25 - 0.50 | LT 0.10 | LT 0.25 | LT 0.25 |
| Stevens Pass | 0.50 - 0.75 | LT 0.25 | 0.25 | 0.25 - 0.50 |
| Snoqualmie Pass | 0.50 - 0.75 | LT 0.25 | 0.25 | 0.50 |
| Mission Ridge | 0.25 - 0.50 | 0 | 0.25 | 0.25 |
| Crystal Mt | 0.25 - 0.50 | LT 0.25 | 0.25 | 1.00 |
| Paradise | 1.00 - 1.50 | 0.25 | 0.50 | 1.00 |
| White Pass | 0.50 - 0.75 | LT 0.10 | LT 0.25 | 0.50 - 0.75 |
| Mt Hood Meadows | 0.75 | LT 0.10 | LT 0.10 | 0.50 |
| Timberline | 0.75 | LT 0.10 | LT 0.25 | 0.50 |
| Hurricane Ridge | Precipitation Forecast |
|---|---|
| Tuesday Night | 0.25 - 0.50 |
| Tuesday | LT 0.10 |
| Tuesday Night | 0.50 - 0.75 |
| Tuesday | 0.75 -1.00 |
| Mt Baker Ski Area | Precipitation Forecast |
|---|---|
| Tuesday Night | 0.50 - 0.75 |
| Tuesday | 0.25 |
| Tuesday Night | 1.00 - 1.50 |
| Tuesday | 2.00 |
| Washington Pass | Precipitation Forecast |
|---|---|
| Tuesday Night | 0.25 |
| Tuesday | 0.25 |
| Tuesday Night | 0.50 |
| Tuesday | 0.75 -1.00 |
| Leavenworth | Precipitation Forecast |
|---|---|
| Tuesday Night | 0.25 - 0.50 |
| Tuesday | LT 0.10 |
| Tuesday Night | LT 0.25 |
| Tuesday | LT 0.25 |
| Stevens Pass | Precipitation Forecast |
|---|---|
| Tuesday Night | 0.50 - 0.75 |
| Tuesday | LT 0.25 |
| Tuesday Night | 0.25 |
| Tuesday | 0.25 - 0.50 |
| Snoqualmie Pass | Precipitation Forecast |
|---|---|
| Tuesday Night | 0.50 - 0.75 |
| Tuesday | LT 0.25 |
| Tuesday Night | 0.25 |
| Tuesday | 0.50 |
| Mission Ridge | Precipitation Forecast |
|---|---|
| Tuesday Night | 0.25 - 0.50 |
| Tuesday | 0 |
| Tuesday Night | 0.25 |
| Tuesday | 0.25 |
| Crystal Mt | Precipitation Forecast |
|---|---|
| Tuesday Night | 0.25 - 0.50 |
| Tuesday | LT 0.25 |
| Tuesday Night | 0.25 |
| Tuesday | 1.00 |
| Paradise | Precipitation Forecast |
|---|---|
| Tuesday Night | 1.00 - 1.50 |
| Tuesday | 0.25 |
| Tuesday Night | 0.50 |
| Tuesday | 1.00 |
| White Pass | Precipitation Forecast |
|---|---|
| Tuesday Night | 0.50 - 0.75 |
| Tuesday | LT 0.10 |
| Tuesday Night | LT 0.25 |
| Tuesday | 0.50 - 0.75 |
| Mt Hood Meadows | Precipitation Forecast |
|---|---|
| Tuesday Night | 0.75 |
| Tuesday | LT 0.10 |
| Tuesday Night | LT 0.10 |
| Tuesday | 0.50 |
| Timberline | Precipitation Forecast |
|---|---|
| Tuesday Night | 0.75 |
| Tuesday | LT 0.10 |
| Tuesday Night | LT 0.25 |
| Tuesday | 0.50 |
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: 2:47 PM PST Tuesday, December 18, 2018
Free Winds at 5000' (mph)
| Hurricane Ridge | Mt. Baker | Stevens to Snoqualmie Pass | Mt. Rainier | Mt. Hood | |
|---|---|---|---|---|---|
| Tuesday Evening | WSW 30 - 45 | WSW 25 - 35 | WSW 30 - 45 | WSW 30 - 45 | WSW 40 - 60 |
| Tuesday Night | WSW 25 - 35 | WSW 20 - 30 | WSW 25 - 35 | WSW 25 - 35 | WSW 30 - 45 |
| Wednesday Morning | SW 20 - 30 | SW 25 - 35 | SW 25 - 35 | SW 20 - 30 | WSW 20 - 30 |
| Wednesday Afternoon | S 15 - 25 | S 10 - 20 | SSW 5 - 15 | SW 5 - 15 | SSE 5 - 15 |
| Hurricane Ridge | Elevation |
|---|---|
| Tuesday Evening | WSW 30 - 45 |
| Tuesday Night | WSW 25 - 35 |
| Wednesday Morning | SW 20 - 30 |
| Wednesday Afternoon | S 15 - 25 |
| Mt. Baker | Elevation |
|---|---|
| Tuesday Evening | WSW 25 - 35 |
| Tuesday Night | WSW 20 - 30 |
| Wednesday Morning | SW 25 - 35 |
| Wednesday Afternoon | S 10 - 20 |
| Stevens and Snoqualmie Pass | Elevation |
|---|---|
| Tuesday Evening | WSW 30 - 45 |
| Tuesday Night | WSW 25 - 35 |
| Wednesday Morning | SW 25 - 35 |
| Wednesday Afternoon | SSW 5 - 15 |
| Mt. Rainier | Elevation |
|---|---|
| Tuesday Evening | WSW 30 - 45 |
| Tuesday Night | WSW 25 - 35 |
| Wednesday Morning | SW 20 - 30 |
| Wednesday Afternoon | SW 5 - 15 |
| Mt. Hood | Elevation |
|---|---|
| Tuesday Evening | WSW 40 - 60 |
| Tuesday Night | WSW 30 - 45 |
| Wednesday Morning | WSW 20 - 30 |
| Wednesday Afternoon | SSE 5 - 15 |
| Hurricane Ridge | Direction - Speed |
|---|---|
| Tuesday Evening | WSW 30 - 45 |
| Tuesday Night | WSW 25 - 35 |
| Wednesday Morning | SW 20 - 30 |
| Wednesday Afternoon | S 15 - 25 |
| Mt. Baker | Direction - Speed |
|---|---|
| Tuesday Evening | WSW 25 - 35 |
| Tuesday Night | WSW 20 - 30 |
| Wednesday Morning | SW 25 - 35 |
| Wednesday Afternoon | S 10 - 20 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Tuesday Evening | WSW 30 - 45 |
| Tuesday Night | WSW 25 - 35 |
| Wednesday Morning | SW 25 - 35 |
| Wednesday Afternoon | SSW 5 - 15 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Tuesday Evening | WSW 30 - 45 |
| Tuesday Night | WSW 25 - 35 |
| Wednesday Morning | SW 20 - 30 |
| Wednesday Afternoon | SW 5 - 15 |
| Mt. Hood | Direction - Speed |
|---|---|
| Tuesday Evening | WSW 40 - 60 |
| Tuesday Night | WSW 30 - 45 |
| Wednesday Morning | WSW 20 - 30 |
| Wednesday Afternoon | SSE 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 Evening | WSW 40 - 60 | WSW 35 - 50 | WSW 50 - 70 | WSW 50 - 70 | WSW 55 - 75 |
| Tuesday Night | WSW 40 - 60 | WSW 45 - 65 | WSW 45 - 65 | WSW 45 - 65 | WSW 50 - 70 |
| Wednesday Morning | WSW 30 - 45 | WSW 35 - 50 | WSW 30 - 45 | WSW 35 - 50 | WSW 35 - 50 |
| Wednesday Afternoon | SW 15 - 25 | SW 15 - 25 | SW 30 - 45 | SW 35 - 50 | SW 55 - 75 |
| Mt. Baker | Direction - Speed |
|---|---|
| Tuesday Evening | WSW 40 - 60 |
| Tuesday Night | WSW 40 - 60 |
| Wednesday Morning | WSW 30 - 45 |
| Wednesday Afternoon | SW 15 - 25 |
| Washington Pass | Direction - Speed |
|---|---|
| Tuesday Evening | WSW 35 - 50 |
| Tuesday Night | WSW 45 - 65 |
| Wednesday Morning | WSW 35 - 50 |
| Wednesday Afternoon | SW 15 - 25 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Tuesday Evening | WSW 50 - 70 |
| Tuesday Night | WSW 45 - 65 |
| Wednesday Morning | WSW 30 - 45 |
| Wednesday Afternoon | SW 30 - 45 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Tuesday Evening | WSW 50 - 70 |
| Tuesday Night | WSW 45 - 65 |
| Wednesday Morning | WSW 35 - 50 |
| Wednesday Afternoon | SW 35 - 50 |
| Mt. Hood | Direction - Speed |
|---|---|
| Tuesday Evening | WSW 55 - 75 |
| Tuesday Night | WSW 50 - 70 |
| Wednesday Morning | WSW 35 - 50 |
| Wednesday Afternoon | SW 55 - 75 |
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: 2:47 PM PST Tuesday, December 18, 2018
Extended Weather Synopsis for Tuesday night through Tuesday
Post-frontal showers will decrease Thursday night under low snow levels.
Friday and Friday night will bring a relative break in the onslaught of storms with cool air in place and a very weak high pressure keeping only a few light snow showers in the forecast. A weak front will tries to impact the region on Saturday morning but generally weakens.
The next major storm system will begin to impact the region late in the day Saturday with rain/snow and wind arriving along the coastline.
Extended Snow/Freezing Levels
| Mt. Baker | Snoqualmie Pass | Mt. Hood | Easterly Flow * | ||
|---|---|---|---|---|---|
| Thursday Night | Snow Level | 0' - 2000' | 0' - 2000' | 1000' - 3000' | |
| Friday | Snow Level | 0' - 2000' | 0' - 2000' | 1000' - 3000' | |
| Friday Night | Snow Level | 0' - 2000' | 0' - 2000' | 0' - 2000' | |
| Saturday | Snow Level | 0' - 2000' | 0' - 2000' | 1000' - 3000' | * |
| Mt. Baker | Elevation |
|---|---|
| Thursday Night |
Snow Level 0' - 2000' |
| Friday |
Snow Level 0' - 2000' |
| Friday Night |
Snow Level 0' - 2000' |
| Saturday |
Snow Level 0' - 2000' (Easterly Flow *) |
| Snoqualmie Pass | Elevation |
|---|---|
| Thursday Night |
Snow Level 0' - 2000' |
| Friday |
Snow Level 0' - 2000' |
| Friday Night |
Snow Level 0' - 2000' |
| Saturday |
Snow Level 0' - 2000' (Easterly Flow *) |
| Mt. Hood | Elevation |
|---|---|
| Thursday Night |
Snow Level 1000' - 3000' |
| Friday |
Snow Level 1000' - 3000' |
| Friday Night |
Snow Level 0' - 2000' |
| Saturday |
Snow Level 1000' - 3000' (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.
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 18, 2018
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