Fresh snow boosts Cascade snowpack, with warm, wet weather arriving next week

The snow has been piling up in the mountains since Tuesday this week, much to the delight of skiers and snowboarders, and the displeasure of Cascade Pass motorists. A series of weather systems tracking onshore from the Gulf of Alaska generated the mountain snow with rain in the lowlands of Western Washington.

How much snow fell in the Cascades

Cascade snow amounts were advertised to have two to four feet of new snow. The actual amounts from Tuesday through Thursday afternoon were lighter, yet still substantial.

Paradise on Mt. Rainier got 30 inches of fresh snow, Alpental and Crystal Mountain received about a foot and a half, and all other Northwest Avalanche Center snow reports were around two feet of new snow during this 72-hour period.

Catch up to average?

The period of warm, wet December weather with snow levels above 6,000 feet left the mountain snowpack well behind average. Since the latter part of December, snow has finally been falling in the mountains. This latest burst of snowfall helped ease the mountain snowpack deficit. The improvement now is between 55-65% of the average for the early part of January. An exception is the North Cascades, which is now close to 100% of average.

A big weather change

A major change to a warmer-weather pattern is set to unfold over the weekend and into next week. Higher pressure aloft is forecast to build over the Pacific Northwest, accompanied by a warmer air mass. In addition, an atmospheric river-oriented Pacific weather system is expected to follow and bring warmer rain into the region Sunday into Monday.

Snow levels are forecast to rise to near 7,000 feet on Monday, soaking the fresh snow with rain in lower elevations.

Time to hit the slopes

For mountain snow enthusiasts, Friday and Saturday are your days to enjoy the fresh snow in near-ideal conditions before it is compromised by the warmer rain. The rain-soaked snow is likely to increase the avalanche danger on steeper slopes by early next week as well.

Western WA weekend weather

For the lowlands of Western Washington heading into this weekend, Friday will offer welcome sunbreaks with high temperatures reaching close to 50 degrees. Saturday is expected to have an increase in cloud cover as the next weather system approaches. Rain is forecast to spread onshore overnight Saturday and continue at times Sunday and Monday. High temperatures on Monday are anticipated to climb well into the 50s. The average high temperature is in the upper 40s.

Many parts of Western Washington are expected to receive between a half and 1.5 inches of rain Sunday and Monday. Rivers are forecast to rise, with a few threatening to reach flood stage. This situation bears watching.

Later next week

Higher pressure aloft is forecast to rebuild over the region starting Tuesday and continue through much of next week. This dry weather pattern promises more sunshine with mild high temperatures generally in the 50s and lows ranging from the mid-30s to mid-40s.

Yet this warm, dry weather pattern does not bode well for additional mountain snow next week, and it likely extends into the following week.

Ted Buehner is the KIRO Newsradio meteorologist. Follow him on X and Bluesky. Read more of his stories here.