A weak cold front is bringing a few light showers along and west of the Cascades with reports of only a few hundredths to a tenth of an inch, mainly at the higher elevations. This system will continue to bring isolated light showers this evening ending near midnight across the area. Once the front moves off to the east a high pressure ridge from the Pacific will begin to build into the region.
This ridge will bring mild and sunny conditions to the coast and higher elevations, with increasing west-side valley fog through the week for low-lying areas. Tuesday should bring at least some sunshine by the afternoon to valley locations which will allow temperatures to climb into the 40s; for areas that don’t see that sunshine temperatures may struggle to reach 40. Christmas Day and Thursday will bring the thickest fog and low-clouds to valley locations and thus much cooler temperatures. Some areas will miss out on the sunshine these days which will keep temperatures in the low-30s through the day, for locations that see sunshine peak through in the afternoon will see high’s climb into the 40s. The densest fog will be in the Rogue and Illinois Valleys as well as the Umpqua Basin. For those traveling on Christmas or the day after you should leave extra time for travel due to reduced visibility. Air quality will also deteriorate through the week as the inversion strengthens and an Air Stagnation Advisory is in place through noon Saturday for Oregon low-lying areas. You can find current air quality levels under Weather Links.
A splitting storm will arrive late Friday into early Saturday and this may be enough to mix up the atmosphere and clear out the valley fog while keeping us dry. No significant rain is in the forecast for the rest of the year meaning which will lead to a record breaking dry year for many cities in our viewing area.
Thanks for logging on and have a Merry Christmas Eve!
Meteorologist Megan Parry