Jump to: Weather Forecast I Snow/Freezing Level I Precipitation I Free Winds 5k I Free Winds 9k
Weather Synopsis for Thursday & Wednesday
An atmospheric river is poised to impact the Pacific Northwest over Thursday through Saturday. The initial moisture is moving into the Washington coastline and northern Oregon early Thursday morning. It will gradually spread northward throughout the day, reaching the Mt. Rainier area by late morning and Snoqualmie Pass during the afternoon. The largest impacts today will be in the Mt. Hood area where snow totals should be 10-18" , winds will become strong to extreme at 5000 ft, and snow levels will rise.
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. 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 and it wouldn't surprise us if the E flow kept Snoqualmie Pass all snow until Friday morning.
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.
Weather Forecast
Hurricane Ridge
| Thursday | Increasing light rain and snow, particularly during the afternoon hours. |
Mt. Baker
| Thursday | Periods of lights rain and snow. |
Washington Pass and Leavenworth
| Thursday | Periods of light snow early, then cloudy in the middle of the day before light snow increases in the southern part late in the day. |
Stevens and Snoqualmie Pass
| Thursday | Isolated rain and snow showers generally ending in the morning. Rain and snow increasing and becoming moderate in the afternoon. Moderate E flow through the passes becoming strong in the afternoon. |
Mt. Rainier, Crystal and White Pass
| Thursday | Cloudy early with increasing snow late morning becoming moderate to heavy in the afternoon. Becoming very stormy late in the day. Expect 6-12" snow during the day for Paradise with slightly less elsewhere. |
Mt. Hood
| Thursday | Heavy snow developing and becoming very stormy with strong winds in the morning becoming extreme. |
Issued: 7:08 AM 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 Morning | Snow Level * | 3000' | 2500' | 2500' | 1000' | 2500' | 2500' | 3000' | 4000' |
| Thursday Afternoon | Snow Level * | 3500' | 3000' | 2500' | 1000' | 3500' | 3000' | 3500' | 5000' |
| Thursday Evening | Snow Level * | 4500' | 3000' | 2000' | 1000' | 3000' | 3000' | 5000' | 6000' |
| Thursday Night | Snow Level * | 4500' | 4500' | 4000' | 5000' | 5500' | 5500' | 5500' | 5500' |
| Friday Morning | Snow Level * | 3500' | 4000' | 4500' | 5500' | 5000' | 5000' | 5000' | 5500' |
| Friday Afternoon | Snow Level | 3000' | 3000' | 4000' | 4500' | 3500' | 3500' | 4500' | 5000' |
| Hurricane Ridge | Elevation |
|---|---|
| Thursday Morning |
Snow Level 3000' (Easterly Flow *) |
| Thursday Afternoon |
Snow Level 3500' (Easterly Flow *) |
| Thursday Evening |
Snow Level 4500' (Easterly Flow *) |
| Thursday Night |
Snow Level 4500' (Easterly Flow *) |
| Friday Morning |
Snow Level 3500' (Easterly Flow *) |
| Friday Afternoon |
Snow Level 3000' |
| Mt. Baker | Elevation |
|---|---|
| Thursday Morning |
Snow Level 2500' (Easterly Flow *) |
| Thursday Afternoon |
Snow Level 3000' (Easterly Flow *) |
| Thursday Evening |
Snow Level 3000' (Easterly Flow *) |
| Thursday Night |
Snow Level 4500' (Easterly Flow *) |
| Friday Morning |
Snow Level 4000' (Easterly Flow *) |
| Friday Afternoon |
Snow Level 3000' |
| Washington Pass | Elevation |
|---|---|
| Thursday Morning |
Snow Level 2500' (Easterly Flow *) |
| Thursday Afternoon |
Snow Level 2500' (Easterly Flow *) |
| Thursday Evening |
Snow Level 2000' (Easterly Flow *) |
| Thursday Night |
Snow Level 4000' (Easterly Flow *) |
| Friday Morning |
Snow Level 4500' (Easterly Flow *) |
| Friday Afternoon |
Snow Level 4000' |
| Leavenworth | Elevation |
|---|---|
| Thursday Morning |
Snow Level 1000' (Easterly Flow *) |
| Thursday Afternoon |
Snow Level 1000' (Easterly Flow *) |
| Thursday Evening |
Snow Level 1000' (Easterly Flow *) |
| Thursday Night |
Snow Level 5000' (Easterly Flow *) |
| Friday Morning |
Snow Level 5500' (Easterly Flow *) |
| Friday Afternoon |
Snow Level 4500' |
| Stevens Pass | Elevation |
|---|---|
| Thursday Morning |
Snow Level 2500' (Easterly Flow *) |
| Thursday Afternoon |
Snow Level 3500' (Easterly Flow *) |
| Thursday Evening |
Snow Level 3000' (Easterly Flow *) |
| Thursday Night |
Snow Level 5500' (Easterly Flow *) |
| Friday Morning |
Snow Level 5000' (Easterly Flow *) |
| Friday Afternoon |
Snow Level 3500' |
| Snoqualmie Pass | Elevation |
|---|---|
| Thursday Morning |
Snow Level 2500' (Easterly Flow *) |
| Thursday Afternoon |
Snow Level 3000' (Easterly Flow *) |
| Thursday Evening |
Snow Level 3000' (Easterly Flow *) |
| Thursday Night |
Snow Level 5500' (Easterly Flow *) |
| Friday Morning |
Snow Level 5000' (Easterly Flow *) |
| Friday Afternoon |
Snow Level 3500' |
| Mt. Rainier & Crystal | Elevation |
|---|---|
| Thursday Morning |
Snow Level 3000' (Easterly Flow *) |
| Thursday Afternoon |
Snow Level 3500' (Easterly Flow *) |
| Thursday Evening |
Snow Level 5000' (Easterly Flow *) |
| Thursday Night |
Snow Level 5500' (Easterly Flow *) |
| Friday Morning |
Snow Level 5000' (Easterly Flow *) |
| Friday Afternoon |
Snow Level 4500' |
| Mt. Hood | Elevation |
|---|---|
| Thursday Morning |
Snow Level 4000' (Easterly Flow *) |
| Thursday Afternoon |
Snow Level 5000' (Easterly Flow *) |
| Thursday Evening |
Snow Level 6000' (Easterly Flow *) |
| Thursday Night |
Snow Level 5500' (Easterly Flow *) |
| Friday Morning |
Snow Level 5500' (Easterly Flow *) |
| Friday 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
| Thursday | Thursday Night | Wednesday | |
|---|---|---|---|
| 4 am - 4 pm | 4 pm - 4 am | 4 am - 4 pm | |
| Hurricane Ridge | LT 0.25 | 0.75 -1.00 | 0.25 - 0.50 |
| Mt Baker Ski Area | LT 0.25 | 1.50 - 2.00 | 0.75 -1.00 |
| Washington Pass | LT 0.25 | 1.00 - 1.50 | 0.75 -1.00 |
| Leavenworth | LT 0.25 | 0.75 | 0.25 - 0.50 |
| Stevens Pass | 0.25 | 1.00 | 1.00 |
| Snoqualmie Pass | 0.25 | 1.50 | 1.00 |
| Mission Ridge | 0.25 | 0.50 | 0.25 |
| Crystal Mt | 0.25 - 0.50 | 1.50 | 1.00 - 1.50 |
| Paradise | 0.75 | 2.00 - 2.50 | 2.00 |
| White Pass | 0.50 - 0.75 | 1.00 | 1.00 |
| Mt Hood Meadows | 1.50 | 0.25 - 0.50 | 0.50 - 0.75 |
| Timberline | 1.50 | 0.25 - 0.50 | 0.50 - 0.75 |
| Hurricane Ridge | Precipitation Forecast |
|---|---|
| Thursday | LT 0.25 |
| Thursday Night | 0.75 -1.00 |
| Wednesday | 0.25 - 0.50 |
| Mt Baker Ski Area | Precipitation Forecast |
|---|---|
| Thursday | LT 0.25 |
| Thursday Night | 1.50 - 2.00 |
| Wednesday | 0.75 -1.00 |
| Washington Pass | Precipitation Forecast |
|---|---|
| Thursday | LT 0.25 |
| Thursday Night | 1.00 - 1.50 |
| Wednesday | 0.75 -1.00 |
| Leavenworth | Precipitation Forecast |
|---|---|
| Thursday | LT 0.25 |
| Thursday Night | 0.75 |
| Wednesday | 0.25 - 0.50 |
| Stevens Pass | Precipitation Forecast |
|---|---|
| Thursday | 0.25 |
| Thursday Night | 1.00 |
| Wednesday | 1.00 |
| Snoqualmie Pass | Precipitation Forecast |
|---|---|
| Thursday | 0.25 |
| Thursday Night | 1.50 |
| Wednesday | 1.00 |
| Mission Ridge | Precipitation Forecast |
|---|---|
| Thursday | 0.25 |
| Thursday Night | 0.50 |
| Wednesday | 0.25 |
| Crystal Mt | Precipitation Forecast |
|---|---|
| Thursday | 0.25 - 0.50 |
| Thursday Night | 1.50 |
| Wednesday | 1.00 - 1.50 |
| Paradise | Precipitation Forecast |
|---|---|
| Thursday | 0.75 |
| Thursday Night | 2.00 - 2.50 |
| Wednesday | 2.00 |
| White Pass | Precipitation Forecast |
|---|---|
| Thursday | 0.50 - 0.75 |
| Thursday Night | 1.00 |
| Wednesday | 1.00 |
| Mt Hood Meadows | Precipitation Forecast |
|---|---|
| Thursday | 1.50 |
| Thursday Night | 0.25 - 0.50 |
| Wednesday | 0.50 - 0.75 |
| Timberline | Precipitation Forecast |
|---|---|
| Thursday | 1.50 |
| Thursday Night | 0.25 - 0.50 |
| Wednesday | 0.50 - 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: 7:08 AM PST Thursday, December 19, 2019
Free Winds at 5000' (mph)
| Hurricane Ridge | Mt. Baker | Stevens to Snoqualmie Pass | Mt. Rainier | Mt. Hood | |
|---|---|---|---|---|---|
| Thursday Morning | S 5 - 15 | SSE 15 - 25 | SSE 10 - 20 | S 10 - 20 | SSW 15 - 25 |
| Thursday Afternoon | SSE 25 - 35 | ESE 20 - 30 | ESE 20 - 30 | SSE 25 - 35 | SW 35 - 45 |
| Thursday Evening | SW 30 - 40 | SE 25 - 35 | S 35 - 45 | SSW 35 - 45 | WSW 50 - 70 |
| Thursday Night | SSW 15 - 25 | SSW 25 - 35 | SSW 35 - 45 | SSW 35 - 45 | SW 55 - 75 |
| Friday Morning | SW 10 - 20 | SW 20 - 30 | SW 25 - 35 | SW 25 - 35 | SW 40 - 60 |
| Friday Afternoon | SSW 5 - 15 | WSW 5 - 15 | SW 10 - 20 | SW 10 - 20 | SW 20 - 30 |
| Hurricane Ridge | Elevation |
|---|---|
| Thursday Morning | S 5 - 15 |
| Thursday Afternoon | SSE 25 - 35 |
| Thursday Evening | SW 30 - 40 |
| Thursday Night | SSW 15 - 25 |
| Friday Morning | SW 10 - 20 |
| Friday Afternoon | SSW 5 - 15 |
| Mt. Baker | Elevation |
|---|---|
| Thursday Morning | SSE 15 - 25 |
| Thursday Afternoon | ESE 20 - 30 |
| Thursday Evening | SE 25 - 35 |
| Thursday Night | SSW 25 - 35 |
| Friday Morning | SW 20 - 30 |
| Friday Afternoon | WSW 5 - 15 |
| Stevens and Snoqualmie Pass | Elevation |
|---|---|
| Thursday Morning | SSE 10 - 20 |
| Thursday Afternoon | ESE 20 - 30 |
| Thursday Evening | S 35 - 45 |
| Thursday Night | SSW 35 - 45 |
| Friday Morning | SW 25 - 35 |
| Friday Afternoon | SW 10 - 20 |
| Mt. Rainier | Elevation |
|---|---|
| Thursday Morning | S 10 - 20 |
| Thursday Afternoon | SSE 25 - 35 |
| Thursday Evening | SSW 35 - 45 |
| Thursday Night | SSW 35 - 45 |
| Friday Morning | SW 25 - 35 |
| Friday Afternoon | SW 10 - 20 |
| Mt. Hood | Elevation |
|---|---|
| Thursday Morning | SSW 15 - 25 |
| Thursday Afternoon | SW 35 - 45 |
| Thursday Evening | WSW 50 - 70 |
| Thursday Night | SW 55 - 75 |
| Friday Morning | SW 40 - 60 |
| Friday Afternoon | SW 20 - 30 |
| Hurricane Ridge | Direction - Speed |
|---|---|
| Thursday Morning | S 5 - 15 |
| Thursday Afternoon | SSE 25 - 35 |
| Thursday Evening | SW 30 - 40 |
| Thursday Night | SSW 15 - 25 |
| Friday Morning | SW 10 - 20 |
| Friday Afternoon | SSW 5 - 15 |
| Mt. Baker | Direction - Speed |
|---|---|
| Thursday Morning | SSE 15 - 25 |
| Thursday Afternoon | ESE 20 - 30 |
| Thursday Evening | SE 25 - 35 |
| Thursday Night | SSW 25 - 35 |
| Friday Morning | SW 20 - 30 |
| Friday Afternoon | WSW 5 - 15 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Thursday Morning | SSE 10 - 20 |
| Thursday Afternoon | ESE 20 - 30 |
| Thursday Evening | S 35 - 45 |
| Thursday Night | SSW 35 - 45 |
| Friday Morning | SW 25 - 35 |
| Friday Afternoon | SW 10 - 20 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Thursday Morning | S 10 - 20 |
| Thursday Afternoon | SSE 25 - 35 |
| Thursday Evening | SSW 35 - 45 |
| Thursday Night | SSW 35 - 45 |
| Friday Morning | SW 25 - 35 |
| Friday Afternoon | SW 10 - 20 |
| Mt. Hood | Direction - Speed |
|---|---|
| Thursday Morning | SSW 15 - 25 |
| Thursday Afternoon | SW 35 - 45 |
| Thursday Evening | WSW 50 - 70 |
| Thursday Night | SW 55 - 75 |
| Friday Morning | SW 40 - 60 |
| Friday Afternoon | SW 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 | |
|---|---|---|---|---|---|
| Thursday Morning | SSW 15 - 25 | WSW 15 - 25 | WSW 20 - 30 | WSW 15 - 25 | WSW 30 - 40 |
| Thursday Afternoon | SSW 20 - 30 | S 15 - 25 | SW 40 - 60 | SW 50 - 70 | WSW 60 - 80 |
| Thursday Evening | SW 40 - 60 | SW 50 - 65 | SW 65 - 85 | SW 60 - 80 | SW 65 - 85 |
| Thursday Night | SW 35 - 45 | SW 50 - 70 | SW 75 - 95 | SW 65 - 85 | WSW 60 - 80 |
| Friday Morning | SSW 40 - 60 | SW 45 - 60 | SW 55 - 75 | WSW 45 - 60 | WSW 65 - 85 |
| Friday Afternoon | WSW 20 - 30 | WSW 15 - 25 | WSW 35 - 45 | WSW 30 - 40 | WSW 55 - 75 |
| Mt. Baker | Direction - Speed |
|---|---|
| Thursday Morning | SSW 15 - 25 |
| Thursday Afternoon | SSW 20 - 30 |
| Thursday Evening | SW 40 - 60 |
| Thursday Night | SW 35 - 45 |
| Friday Morning | SSW 40 - 60 |
| Friday Afternoon | WSW 20 - 30 |
| Washington Pass | Direction - Speed |
|---|---|
| Thursday Morning | WSW 15 - 25 |
| Thursday Afternoon | S 15 - 25 |
| Thursday Evening | SW 50 - 65 |
| Thursday Night | SW 50 - 70 |
| Friday Morning | SW 45 - 60 |
| Friday Afternoon | WSW 15 - 25 |
| Stevens and Snoqualmie Pass | Direction - Speed |
|---|---|
| Thursday Morning | WSW 20 - 30 |
| Thursday Afternoon | SW 40 - 60 |
| Thursday Evening | SW 65 - 85 |
| Thursday Night | SW 75 - 95 |
| Friday Morning | SW 55 - 75 |
| Friday Afternoon | WSW 35 - 45 |
| Mt. Rainier | Direction - Speed |
|---|---|
| Thursday Morning | WSW 15 - 25 |
| Thursday Afternoon | SW 50 - 70 |
| Thursday Evening | SW 60 - 80 |
| Thursday Night | SW 65 - 85 |
| Friday Morning | WSW 45 - 60 |
| Friday Afternoon | WSW 30 - 40 |
| Mt. Hood | Direction - Speed |
|---|---|
| Thursday Morning | WSW 30 - 40 |
| Thursday Afternoon | WSW 60 - 80 |
| Thursday Evening | SW 65 - 85 |
| Thursday Night | WSW 60 - 80 |
| Friday Morning | WSW 65 - 85 |
| Friday Afternoon | WSW 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.
Jump to: Weather Forecast I Snow/Freezing Level I Precipitation I Free Winds 5k I Free Winds 9k
Previous forecast from Dec 18, 2019
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