SEATTLE - Seahawks playoff football fever is alive and well in Western Washington right now. The Saints have arrived in town for the big game Saturday afternoon, and it won't just be the 'Legion of Boom' that Drew Brees has to contend with. The 12th man will be joined by a strong storm that will pack rain and wind during the game. If winter sports are more your thing, skiers and snowboarders will receive feet of fresh powder by the end of the weekend.
This storm is bringing what I like to call the Western Washington winter trifecta; heavy rain, gusty winds, and lots of snow in the mountains. It’s a dynamic storm that will also bring the potential for some flooding on our local rivers and along the coast. Here is the breakdown.
Looking at the satellite image above taken Friday evening, it's not hard to find the storm that is heading our way. You can see the large plume of subtropical moisture that will bring us a lot of rain over the next 24 hours. The rain has been increasing this evening as the warm front associated with this storm lifts into our area. As the cold front approaches the area late Friday night into early Saturday morning, there will be heavy downpours across the area. Heading into Saturday, the steadiest rain will fall early in the morning. As we head into the day, showers will continue and will be heavy at times through the afternoon for the Seahawks game. Some sunbreaks will be in the mix as well. As the upper-level trough moves over us during the day on Saturday, there could be enough energy to kick off a couple isolated thunderstorms. Rain will start tapering around sunset, with fewer showers expected into Saturday evening.
Rainfall totals around Seattle to Olympia will be in the 1 to 3 inch range. The same goes for the Washington Coast, in the 1 to 3 inch range. Around Everett to Bellingham and the islands, totals will generally be in the 0.5” to 2” range. The northeast Olympic Peninsula (Sequim) will be in the Olympic rain shadow, picking up less than a half inch.
Winds are ramping back up again tonight. A Wind Advisory is in effect for all of Puget Sound through early Saturday morning. Southerly wind gusts up around 45 mph are forecast overnight. The strongest winds will be close to the waters of Puget Sound, especially those areas that are exposed to the south. Even stronger winds are forecast along the coast and over Whidbey Island. A High Wind Warning is in effect for those areas where gusts could reach 65 mph overnight.
During the day on Saturday, the surface low is tracking over Vancouver Island, keeping the wind going throughout the day. Southwesterly sustained winds that will continue to be in the 20-30 mph range with gusts up to 50 mph for the Sound. This is the type of wind we can expect during the Seahawks game.
The wind we experience tonight and tomorrow could be damaging and cause some power outages.
With snow levels rising up around 6,000 feet Friday night through early Saturday morning, there will be a lot of runoff into our local rivers. Forecast rainfall over the mountains is in the 3 to 5 inch range, especially for the southwest facing slopes.
Some of the rivers most likely to experience minor flooding will be the Skokomish near Potlatch, the Puyallup near Orting, Tolt near Carnation, Stillaguamish near Carnation, and the Newaukum near Chehalis.
In addition to our rivers, some coastal flooding is also possible during this evening. A Coastal Flood Watch has been issued for the north and central Washington Coast. Large swells nearing 30 feet are forecast from 4 p.m. Saturday to 4 a.m. Sunday. Ocean Shores and Westport are most at risk for coastal flooding. Tides do not look to play a major role in the flooding; it will be the large waves.
Rain has been falling over the passes for most of the day, and it will continue overnight as the warmer part of this storm moves through. By Saturday afternoon, colder air will have arrived, causing the snow level to crash back down to Snoqualmie Pass. Heavy snow will be falling over the Cascades through Saturday evening; we'll be counting it in feet. A Winter Storm Warning has been issued, with 1 to 2 feet of new snow through the weekend. Delays and closures are likely over the passes if you have travel plans. With the transition back-and-forth from rain to snow, the avalanche danger will grow higher on Saturday.
Once this storm moves out, another system is on its heels for Sunday. This will not be as strong of a storm, but it will bring rain at times throughout the day along with breezy conditions. We’re moving in a drier direction early next week with fewer scattered showers on Monday. Tuesday looks dry with some sun working out again.
Have a great day!