Jump to: Weather Forecast I Snow/Freezing Level I Precipitation I Free Winds 5k I Free Winds 9k I Extended Weather
Weather Synopsis for Thursday night through Wednesday
A deep Gulf of Alaska low-pressure system and associated high amplitude offshore trough have tapped into a subtropical moisture feed with a strong jet stream taking aim on the Pacific Northwest Thursday through Saturday.
Thursday night and Friday the greatest impacts will be in Washington state as the moisture feed takes aim on the region. Most of our mountain stations should pick up 1-5" of precipitable water, with strong to extreme winds, and rising snow levels impacting the entire region.
With cold air in place, particularly east of the Cascade Crest, the region will become a battleground between the warm, moist air and the colder entrenched air on Thursday night with strong warming during that time period. Thus, we expect strong easterly gradients to keep the Cascade Passes all snow through the evening hours, but a changeover to rain is likely by Friday morning. Model soundings indicate good potential for freezing rain at Snoqualmie Pass during the transition. These events are very difficult to forecast with strong winds to mix the warm air down, but also cold (low to mid 20's) temperatures east of the Cascade Crest that will be difficult to displace. Some cooling is expected as the frontal zone moves slightly on Friday. We expect Washington Pass to remain all snow, Mt. Baker and Hurricane Ridge may change to rain briefly early morning on Friday. Most other major access points should see a changeover to rain by the early morning hours on Friday and won't change back to snow at ski area bases until Saturday.
The fire hose continues to take aim on the region Friday night into Saturday with precipitation gradually decreasing, but still moderate to heavy at times. Friday night features a slight warm-up, before the frontal zone shifts gradually eastward, bringing additional drying and cooling from west to east.
Weather Forecast
Hurricane Ridge
| Thursday Night | Heavy rain and snow. Strong winds in the evening decreasing. Rising snow levels. |
| Friday | Moderate rain and snow. Gradually falling snow levels. |
Mt. Baker
| Thursday Night | Very heavy rain and snow. Strong crest-level winds. Rising snow levels. |
| Friday | Heavy rain and snow. Strong crest-level winds. Gradually falling snow levels. |
Washington Pass and Leavenworth
| Thursday Night | Heavy rain and snow. Strong crest-level winds. |
| Friday | Heavy rain and snow. Strong crest-level winds. |
Stevens and Snoqualmie Pass
| Thursday Night | Heavy snow near and east of the Passes, with rain gradually overtaking from the west. There may be a transition to freezing rain at Snoqualmie Pass. The transition likely between 10 PM and 4 AM, with Stevens Pass several hours after Snoqualmie. E winds through the passes E 15-25 mph decreasing after midnight. Strong crest-level winds. |
| Friday | Heavy rain with snow at upper elevations. Strong crest-level winds. Variable winds, mostly light westerly at pass level. |
Mt. Rainier, Crystal and White Pass
| Thursday Night | Heavy rain and snow with rising snow levels. Strong crest-level winds. |
| Friday | Heavy rain and snow. Strong crest-level winds. |
Mt. Hood
| Thursday Night | Moderate rain and snow in the evening becoming light or ending after midnight. Mild. Strong to extreme winds above treeline. |
| Friday | Cloudy with a chance of rain or snow. Mild. Strong to extreme winds above treeline. |
Issued: 2:52 PM PST Thursday, December 19, 2019
Snow/Freezing Level (ft)
| Hurricane Ridge | Mt. Baker | Washington Pass | Leavenworth | Stevens Pass | Snoqualmie Pass | Mt. Rainier, Crystal & White Pass | Mt. Hood | ||
|---|---|---|---|---|---|---|---|---|---|
| Thursday Evening | Snow Level * | 5500' | 3000' | 1500' | 1500' | 2500' | 3000' | 4500' | 6000' |
| Thursday Night | Snow Level * | 5000' | 4000' | 3000' | 4000' | 5000' | 5500' | 6000' | 6000' |
| Friday Morning | Snow Level | 4000' | 4000' | 4000' | 5500' | 5000' | 5500' | 5500' | 6000' |
| Friday Afternoon | Snow Level | 4000' | 4000' | 4500' | 5000' | 5000' | 5000' | 5500' | 6000' |
| Friday Evening | Snow Level * | 3500' | 3500' | 4500' | 5000' | 4500' | 4500' | 5000' | 6500' |
| Friday Night | Snow Level * | 3000' | 3000' | 4000' | 5000' | 4500' | 5000' | 5000' | 6500' |
| Saturday Morning | Snow Level | 2500' | 3500' | 4000' | 5000' | 4500' | 4500' | 4500' | 5500' |
| Saturday Afternoon | Snow Level | 2500' | 3000' | 4000' | 4500' | 4000' | 4000' | 4000' | 4500' |
| Hurricane Ridge | Elevation |
|---|---|
| Thursday Evening |
Snow Level 5500' (Easterly Flow *) |
| Thursday Night |
Snow Level 5000' (Easterly Flow *) |
| Friday Morning |
Snow Level 4000' |
| Friday Afternoon |
Snow Level 4000' |
| Friday Evening |
Snow Level 3500' (Easterly Flow *) |
| Friday Night |
Snow Level 3000' (Easterly Flow *) |
| Saturday Morning |
Snow Level 2500' |
| Saturday Afternoon |
Snow Level 2500' |
| Mt. Baker | Elevation |
|---|---|
| Thursday Evening |
Snow Level 3000' (Easterly Flow *) |
| Thursday Night |
Snow Level 4000' (Easterly Flow *) |
| Friday Morning |
Snow Level 4000' |
| Friday Afternoon |
Snow Level 4000' |
| Friday Evening |
Snow Level 3500' (Easterly Flow *) |
| Friday Night |
Snow Level 3000' (Easterly Flow *) |
| Saturday Morning |
Snow Level 3500' |
| Saturday Afternoon |
Snow Level 3000' |
| Washington Pass | Elevation |
|---|---|
| Thursday Evening |
Snow Level 1500' (Easterly Flow *) |
| Thursday Night |
Snow Level 3000' (Easterly Flow *) |
| Friday Morning |
Snow Level 4000' |
| Friday Afternoon |
Snow Level 4500' |
| Friday Evening |
Snow Level 4500' (Easterly Flow *) |
| Friday Night |
Snow Level 4000' (Easterly Flow *) |
| Saturday Morning |
Snow Level 4000' |
| Saturday Afternoon |
Snow Level 4000' |
| Leavenworth | Elevation |
|---|---|
| Thursday Evening |
Snow Level 1500' (Easterly Flow *) |
| Thursday Night |
Snow Level 4000' (Easterly Flow *) |
| Friday Morning |
Snow Level 5500' |
| Friday Afternoon |
Snow Level 5000' |
| Friday Evening |
Snow Level 5000' (Easterly Flow *) |
| Friday Night |
Snow Level 5000' (Easterly Flow *) |
| Saturday Morning |
Snow Level 5000' |
| Saturday Afternoon |
Snow Level 4500' |
| Stevens Pass | Elevation |
|---|---|
| Thursday Evening |
Snow Level 2500' (Easterly Flow *) |
| Thursday Night |
Snow Level 5000' (Easterly Flow *) |
| Friday Morning |
Snow Level 5000' |
| Friday Afternoon |
Snow Level 5000' |
| Friday Evening |
Snow Level 4500' (Easterly Flow *) |
| Friday Night |
Snow Level 4500' (Easterly Flow *) |
| Saturday Morning |
Snow Level 4500' |
| Saturday Afternoon |
Snow Level 4000' |
| Snoqualmie Pass | Elevation |
|---|---|
| Thursday Evening |
Snow Level 3000' (Easterly Flow *) |
| Thursday Night |
Snow Level 5500' (Easterly Flow *) |
| Friday Morning |
Snow Level 5500' |
| Friday Afternoon |
Snow Level 5000' |
| Friday Evening |
Snow Level 4500' (Easterly Flow *) |
| Friday Night |
Snow Level 5000' (Easterly Flow *) |
| Saturday Morning |
Snow Level 4500' |
| Saturday Afternoon |
Snow Level 4000' |
| Mt. Rainier & Crystal | Elevation |
|---|---|
| Thursday Evening |
Snow Level 4500' (Easterly Flow *) |
| Thursday Night |
Snow Level 6000' (Easterly Flow *) |
| Friday Morning |
Snow Level 5500' |
| Friday Afternoon |
Snow Level 5500' |
| Friday Evening |
Snow Level 5000' (Easterly Flow *) |
| Friday Night |
Snow Level 5000' (Easterly Flow *) |
| Saturday Morning |
Snow Level 4500' |
| Saturday Afternoon |
Snow Level 4000' |
| Mt. Hood | Elevation |
|---|---|
| Thursday Evening |
Snow Level 6000' (Easterly Flow *) |
| Thursday Night |
Snow Level 6000' (Easterly Flow *) |
| Friday Morning |
Snow Level 6000' |
| Friday Afternoon |
Snow Level 6000' |
| Friday Evening |
Snow Level 6500' (Easterly Flow *) |
| Friday Night |
Snow Level 6500' (Easterly Flow *) |
| Saturday Morning |
Snow Level 5500' |
| Saturday Afternoon |
Snow Level 4500' |
* 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
| Thursday Night | Wednesday | Wednesday Night | Wednesday | |
|---|---|---|---|---|
| 4 pm - 4 am | 4 am - 4 pm | 4 pm - 4 am | 4 am - 4 pm | |
| Hurricane Ridge | 0.75 -1.00 | 0.25 - 0.50 | 0.50 - 0.75 | 0.25 |
| Mt Baker Ski Area | 1.50 - 2.00 | 1.00 | 0.75 -1.00 | 0.75 |
| Washington Pass | 1.00 - 1.50 | 0.75 -1.00 | 0.50 | 0.50 |
| Leavenworth | 0.75 | 0.25 - 0.50 | 0.25 | LT 0.10 |
| Stevens Pass | 1.50 | 1.00 - 1.50 | 0.50 | 0.25 |
| Snoqualmie Pass | 1.50 - 2.00 | 1.00 - 1.50 | 0.75 | 0.25 |
| Mission Ridge | 0.50 | 0.25 | 0.25 - 0.50 | LT 0.25 |
| Crystal Mt | 1.50 | 1.00 - 1.50 | 1.00 | 0.25 - 0.50 |
| Paradise | 2.00 | 2.00 | 1.50 | 0.75 |
| White Pass | 0.75 -1.00 | 1.00 | 0.75 | 0.25 - 0.50 |
| Mt Hood Meadows | 0.25 - 0.50 | 0.25 - 0.50 | LT 0.25 | 0.25 - 0.50 |
| Timberline | 0.25 - 0.50 | 0.25 - 0.50 | LT 0.25 | 0.25 - 0.50 |
| Hurricane Ridge | Precipitation Forecast |
|---|---|
| Thursday Night | 0.75 -1.00 |
| Wednesday | 0.25 - 0.50 |
| Wednesday Night | 0.50 - 0.75 |
| Wednesday | 0.25 |
| Mt Baker Ski Area | Precipitation Forecast |
|---|---|
| Thursday Night | 1.50 - 2.00 |
| Wednesday | 1.00 |
| Wednesday Night | 0.75 -1.00 |
| Wednesday | 0.75 |
| Washington Pass | Precipitation Forecast |
|---|---|
| Thursday Night | 1.00 - 1.50 |
| Wednesday | 0.75 -1.00 |
| Wednesday Night | 0.50 |
| Wednesday | 0.50 |
| Leavenworth | Precipitation Forecast |
|---|---|
| Thursday Night | 0.75 |
| Wednesday | 0.25 - 0.50 |
| Wednesday Night | 0.25 |
| Wednesday | LT 0.10 |
| Stevens Pass | Precipitation Forecast |
|---|---|
| Thursday Night | 1.50 |
| Wednesday | 1.00 - 1.50 |
| Wednesday Night | 0.50 |
| Wednesday | 0.25 |
| Snoqualmie Pass | Precipitation Forecast |
|---|---|
| Thursday Night | 1.50 - 2.00 |
| Wednesday | 1.00 - 1.50 |
| Wednesday Night | 0.75 |
| Wednesday | 0.25 |
| Mission Ridge | Precipitation Forecast |
|---|---|
| Thursday Night | 0.50 |
| Wednesday | 0.25 |
| Wednesday Night | 0.25 - 0.50 |
| Wednesday | LT 0.25 |
| Crystal Mt | Precipitation Forecast |
|---|---|
| Thursday Night | 1.50 |
| Wednesday | 1.00 - 1.50 |
| Wednesday Night | 1.00 |
| Wednesday | 0.25 - 0.50 |
| Paradise | Precipitation Forecast |
|---|---|
| Thursday Night | 2.00 |
| Wednesday | 2.00 |
| Wednesday Night | 1.50 |
| Wednesday | 0.75 |
| White Pass | Precipitation Forecast |
|---|---|
| Thursday Night | 0.75 -1.00 |
| Wednesday | 1.00 |
| Wednesday Night | 0.75 |
| Wednesday | 0.25 - 0.50 |
| Mt Hood Meadows | Precipitation Forecast |
|---|---|
| Thursday Night | 0.25 - 0.50 |
| Wednesday | 0.25 - 0.50 |
| Wednesday Night | LT 0.25 |
| Wednesday | 0.25 - 0.50 |
| Timberline | Precipitation Forecast |
|---|---|
| Thursday Night | 0.25 - 0.50 |
| Wednesday | 0.25 - 0.50 |
| Wednesday Night | LT 0.25 |
| Wednesday | 0.25 - 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: 2:52 PM PST Thursday, December 19, 2019
Free Winds at 5000' (mph)
| Hurricane Ridge | Mt. Baker | Stevens to Snoqualmie Pass | Mt. Rainier | Mt. Hood | |
|---|---|---|---|---|---|
| Thursday Evening | SW 20 - 30 | SE 20 - 30 | S 20 - 30 | SSW 20 - 30 | WSW 35 - 45 |
| Thursday Night | SW 10 - 20 | S 20 - 30 | SSW 25 - 35 | SSW 25 - 35 | SW 45 - 65 |
| Friday Morning | SSW 10 - 20 | SSW 15 - 25 | SW 20 - 30 | SW 20 - 30 | SW 35 - 45 |
| Friday Afternoon | SW 5 - 15 | SW 10 - 20 | SW 20 - 30 | SW 20 - 30 | SW 25 - 35 |
| Hurricane Ridge | Elevation |
|---|---|
| Thursday Evening | SW 20 - 30 |
| Thursday Night | SW 10 - 20 |
| Friday Morning | SSW 10 - 20 |
| Friday Afternoon | SW 5 - 15 |
| Mt. Baker | Elevation |
|---|---|
| Thursday Evening | SE 20 - 30 |
| Thursday Night | S 20 - 30 |
| Friday Morning | SSW 15 - 25 |
| Friday Afternoon | SW 10 - 20 |
| Stevens and Snoqualmie Pass | Elevation |
|---|---|
| Thursday Evening | S 20 - 30 |
| Thursday Night | SSW 25 - 35 |
| Friday Morning | SW 20 - 30 |
| Friday Afternoon | SW 20 - 30 |
| Mt. Rainier | Elevation |
|---|---|
| Thursday Evening | SSW 20 - 30 |
| Thursday Night | SSW 25 - 35 |
| Friday Morning | SW 20 - 30 |
| Friday Afternoon | SW 20 - 30 |
| Mt. Hood | Elevation |
|---|---|
| Thursday Evening | WSW 35 - 45 |
| Thursday Night | SW 45 - 65 |
| Friday Morning | SW 35 - 45 |
| Friday Afternoon | SW 25 - 35 |
| Hurricane Ridge | Direction - Speed |
|---|---|
| Thursday Evening | SW 20 - 30 |
| Thursday Night | SW 10 - 20 |
| Friday Morning | SSW 10 - 20 |
| Friday Afternoon | SW 5 - 15 |
| Mt. Baker | Direction - Speed |
|---|---|
| Thursday Evening | SE 20 - 30 |
| Thursday Night | S 20 - 30 |
| Friday Morning | SSW 15 - 25 |
| Friday Afternoon | SW 10 - 20 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Thursday Evening | S 20 - 30 |
| Thursday Night | SSW 25 - 35 |
| Friday Morning | SW 20 - 30 |
| Friday Afternoon | SW 20 - 30 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Thursday Evening | SSW 20 - 30 |
| Thursday Night | SSW 25 - 35 |
| Friday Morning | SW 20 - 30 |
| Friday Afternoon | SW 20 - 30 |
| Mt. Hood | Direction - Speed |
|---|---|
| Thursday Evening | WSW 35 - 45 |
| Thursday Night | SW 45 - 65 |
| Friday Morning | SW 35 - 45 |
| Friday Afternoon | SW 25 - 35 |
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 | |
|---|---|---|---|---|---|
| Thursday Evening | SW 40 - 60 | SW 50 - 65 | SW 65 - 85 | SE 60 - 80 | SW 60 - 80 |
| Thursday Night | SW 30 - 40 | SW 30 - 40 | SW 60 - 80 | SW 60 - 80 | WSW 55 - 75 |
| Friday Morning | SW 30 - 40 | SW 40 - 50 | WSW 45 - 60 | WSW 50 - 70 | WSW 65 - 85 |
| Friday Afternoon | SW 25 - 35 | SW 30 - 40 | SW 45 - 60 | WSW 45 - 60 | WSW 60 - 75 |
| Mt. Baker | Direction - Speed |
|---|---|
| Thursday Evening | SW 40 - 60 |
| Thursday Night | SW 30 - 40 |
| Friday Morning | SW 30 - 40 |
| Friday Afternoon | SW 25 - 35 |
| Washington Pass | Direction - Speed |
|---|---|
| Thursday Evening | SW 50 - 65 |
| Thursday Night | SW 30 - 40 |
| Friday Morning | SW 40 - 50 |
| Friday Afternoon | SW 30 - 40 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Thursday Evening | SW 65 - 85 |
| Thursday Night | SW 60 - 80 |
| Friday Morning | WSW 45 - 60 |
| Friday Afternoon | SW 45 - 60 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Thursday Evening | SE 60 - 80 |
| Thursday Night | SW 60 - 80 |
| Friday Morning | WSW 50 - 70 |
| Friday Afternoon | WSW 45 - 60 |
| Mt. Hood | Direction - Speed |
|---|---|
| Thursday Evening | SW 60 - 80 |
| Thursday Night | WSW 55 - 75 |
| Friday Morning | WSW 65 - 85 |
| Friday Afternoon | WSW 60 - 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: 2:52 PM PST Thursday, December 19, 2019
Extended Weather Synopsis for Wednesday night through Wednesday
Saturday night, moist SSW flow lingers, bringing light rain and snow at lowering snow levels as an offshore trough moves into the region and bringing us back to seasonable temperatures for mid-December. The region largely dries out Sunday and Monday night with a trough axis just offshore digging southward and keeping a weaker system mostly to our south in California and Oregon. Shower activity associated with the trough or the system to the south remains possible.
A dry northerly flow develops on Monday as a weak trough moves into the near-shore waters.
Extended Snow/Freezing Levels
| Mt. Baker | Snoqualmie Pass | Mt. Hood | Easterly Flow * | ||
|---|---|---|---|---|---|
| Saturday Night | Snow Level | 1500' - 2500' | 2500' - 3500' | 3000' - 4000' | |
| Sunday | Freezing Level | 1500' - 2500' | 2000' - 3000' | 2000' - 3000' | |
| Sunday Night | Freezing Level | 1500' - 2500' | 1500' - 2500' | 2000' - 3000' | |
| Monday | Freezing Level | 1000' - 2000' | 1500' - 2500' | 1500' - 2500' |
| Mt. Baker | Elevation |
|---|---|
| Saturday Night |
Snow Level 1500' - 2500' |
| Sunday |
Freezing Level 1500' - 2500' |
| Sunday Night |
Freezing Level 1500' - 2500' |
| Monday |
Freezing Level 1000' - 2000' |
| Snoqualmie Pass | Elevation |
|---|---|
| Saturday Night |
Snow Level 2500' - 3500' |
| Sunday |
Freezing Level 2000' - 3000' |
| Sunday Night |
Freezing Level 1500' - 2500' |
| Monday |
Freezing Level 1500' - 2500' |
| Mt. Hood | Elevation |
|---|---|
| Saturday Night |
Snow Level 3000' - 4000' |
| Sunday |
Freezing Level 2000' - 3000' |
| Sunday Night |
Freezing Level 2000' - 3000' |
| Monday |
Freezing Level 1500' - 2500' |
* 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 19, 2019
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