Key Takeaways
- A Winter Storm Warning takes effect at 5 p.m. today for southwest Washington and the Oregon Cascades, lasting approximately 48 hours.
- Heavy snowfall is expected in the Cascades, with accumulations up to 20 inches at higher elevations and about 1 foot at pass levels.
- Strong winds gusting to 45 mph will accompany the snow in mountainous areas, creating hazardous travel and potential blowing snow/drifts.
- The Willamette Valley and Oregon Coast will receive over an inch of rainfall, alongside increasing gusty winds Tuesday afternoon.
- Precipitation (snow and rain) is expected to taper off by Thursday morning as high pressure builds, bringing drier and warmer conditions.
- A brief improvement will be followed by another low-pressure system moving down the coast, potentially bringing renewed impacts by Sunday.
A Winter Storm Warning has been issued by the National Weather Service offices in Portland and Pendleton, set to begin at 5 p.m. this afternoon and remain in effect through the next 48 hours for portions of southwest Washington and the Oregon Cascades. Meteorologists emphasize that the incoming spring storm system is poised to deliver significant winter weather, particularly to the higher terrain of the central Cascade Mountains. Bobby Corser, a Digital Meteorologist with KATU’s Storm Tracker 2, highlighted that the central mountains are likely to bear the brunt of the heavy snowfall associated with this system.
The primary threat in the Cascade Mountains is substantial snow accumulation. Forecasts indicate snowfall totals could reach up to 20 inches in the highest elevations, while mountain passes and mid-level areas are expected to see approximately one foot (12 inches) of new snow. This significant snowfall will be compounded by strong winds, with gusts anticipated to reach as high as 45 mph. These winds, combined with the heavy snow, will likely create near-blizzard conditions at times, severely reducing visibility, increasing the risk of blowing and drifting snow, and making travel extremely dangerous or impossible on mountain passes and high-elevation roads. Authorities strongly advise against non-essential travel in the warned areas during the peak of the storm.
Lower elevation areas will experience different impacts. In the Willamette Valley and along the Oregon Coast, the storm is expected to bring primarily rainfall rather than snow, due to warmer temperatures at these lower elevations. Forecasts predict rainfall totals exceeding one inch in most locations across these regions. While snow is not the main concern here, the system will also bring increasing gusty winds starting Tuesday afternoon as the associated cold front pushes southeastward through the area. These winds, while likely less intense than in the Cascades, could still cause scattered power outages or make outdoor activities unpleasant, particularly near the coast.
The active period of significant precipitation – both heavy snow in the mountains and rain in the valleys and coast – is forecast to gradually diminish by Thursday morning. As the storm system moves out, a building ridge of high pressure is expected to move into the Pacific Northwest. This shift should usher in a period of drier conditions and gradually warming temperatures, offering a temporary respite from the active weather. This improved weather window, however, is anticipated to be relatively short-lived.
Meteorologists caution that this brief period of calmer, drier weather will not last long. The forecast indicates that another area of low pressure is projected to move down the Pacific Ocean coast, approaching the region by Sunday. This upcoming system has the potential to bring another round of precipitation impacts, whether in the form of rain or snow depending on elevation and temperature profiles, effectively ending the anticipated Thursday-Friday dry spell. Residents are advised to stay updated on forecasts as the weekend approaches for details on this next potential weather system. (Approximately 620 words)