70 mph coastal winds mark arrival of second storm

70 mph coastal winds mark arrival of second storm
SEATTLE -- The second strong storm in as many days was moving through Western Washington Monday night, battering the coast with 70-75 mph winds and promising more rain and wind across the rest of the region.

Hoquiam recorded a sustained wind of 43 mph with a gust of 70 mph at 7 p.m. The 70 mph gust followed a 61 mph gust just before 6 p.m. that must have felt like a freight train because 26 minutes earlier, the wind was at a paltry 7 mph.

Peak gusts so far as of 11 p.m. Monday evening:

  • Hoquiam: 70 mph
  • Astoria: 66 mph
  • Bellingham: 66 mph
  • Oak Harbor: 57 mph
  • Forks: 55 mph
  • Bellingham: 55 mph
  • Alki Beach: 48 mph
  • Everett: 47 mph
  • Friday Harbor: 46 mph
  • 520 Floating Bridge: 43 mph
  • Seattle (Sea-Tac): 43 mph
  • Olympia: 41 mph
  • Everett: 41 mph
  • Gig Harbor: 40 mph

Forecasting models show a second storm center developing just off the coast and tracking into south-central Vancouver Island before rapidly weakening as it moves into the mainland B.C.

With this new storm center closer and more intense, forecasted wind speeds have been increased along the coast and Northwest Interior. High Wind Warnings are in effect there through noon Tuesday.

Wind gusts are now expected to continue to reach as high as 70-75 mph along the coast, and possibly as high as 60-70 mph in the Northwest Interior. Winds will begin gusting here in the 10 p.m.-midnight time frame and last into Tuesday morning.

In the Puget Sound area, the storm is expected to weaken enough before it crosses far enough inland to start our winds going. Here, it's a lesser Wind Advisory in effect until noon Tuesday for potential wind gusts of 40-50 mph, mainly early Tuesday morning.

Meanwhile, the rain just continues non-stop as if not to care how many storms are coming through or which storm goes with what rain.

On Monday night a downed transmission line knocked out power to 10,000 customers in Sumner, Puyallup and Wilkeson. Power was restored before midnight.

Approximately 9,560 customers of Grays Harbor PUD also lost power due to a number of weather-related causes, including downed trees in power lines. It was not known when power would be fully restored.

Some 20 other scattered outages were reported in Whatcom and Skagit counties, as well as Whidbey Island, but only a few customers were affected by each outage.

Lots of rain = flooding

While the wind has been coming and going, the rain has been relentless. Gauges show 6-8 inches of rain had fallen on the southern half of the Olympic Mountains, with more on the way with storm totals set to reach over 10 inches.

Flood Warnings remain in effect for the Skokomish (major flooding), Satsop (moderate flooding), Dungeness (moderate), Bogachiel (minor), Chehalis (minor), Stillaguamish, and Elwha Rivers. Warnings mean flooding is occurring or imminent.

Flood Watches are still in effect for all Olympic Mountain-fed rivers, Whatcom and Skagit County rivers, as well as Lewis and Thurston Counties. We could also see a little urban flooding where clogged drains sprout up spontaneous lakes.

Over on the coast, a Coastal Flood Watch remains in effect Tuesday for the effects from persistent strong south winds, combined with high tide, 20-foot waves, and low atmospheric pressure to cause coastal flooding. The predicted high tide Tuesday is 11.1 feet.

Minor tidal overflow occurs around 13.5 feet, with coastal flooding in Aberdeen at 14.0 feet. These conditions are ripe to add about 2-3 feet to tide table predictions, so thus, the watch. Those along the coast should be prepared for some tidal flooding.

What's going on?

A bit of a curveball developed late Monday afternoon as a secondary storm center formed to the southeast of the main storm which was well offshore. Forecasting models had been waffling back and forth over a secondary storm center, but none had it as strong or as close as this one developed.

So what looked like it would end up being a fairly strong storm far away (and not quite as strong as it appeared Sunday), we also formed a slightly weaker storm, but much closer -- close enough to really ramp up the winds along the coast and northwest interior.

The main center of the storm is still expected to make landfall as well Tuesday morning, keeping the gusty winds going through the night and through the morning, but again, mostly focused along the coast and Northwest Interior.

The Puget Sound area appears to have lucked out in some sense that these storms will be pretty far north and weaker by the time they get to the spot where the draw in the southerly winds.

Still, the storm is powerful enough to bring winds that could be damaging. Plus, we now have the added factor of a day's worth of soaking rains to make the ground soggy, meaning it likely won't take as strong of a wind to knock over trees.

So I'd prepare for potential power outages just in case.

Why so windy for so long?

As to why it's been so persistently windy up north and along the coast -- Bellingham had a 12 hour period of 40 mph gusts -- the storm tracks have been to our northwest and north, carrying large areas of low pressure along for the ride. Air flows from higher pressure to lower pressure and so air is trying to race offshore to meet up with the lower pressure out there.

With little terrain on the coast, air flows unimpeded toward the storm, so wind speeds can get really going. As lower pressure moves north of Forks, air will also shoot out the Straits of Juan de Fuca, Georgia, and across Vancouver Island. The "Northwest Interior", as well call it, has an open path for southeasterly winds to race toward the lower pressure offshore. But for areas south of Everett, the Olympic Mountains are a big wall and prevent a southeast wind from garnering up much steam to head to the northwest. That's why it can be really windy on Whidbey Island for hours on end, but just down the road in Seattle, winds are weaker and don't last near as long.

However, once the storm center moves due north of the region, now instead of a southeast wind, we have a south wind and the Olympics are no longer a factor as the air can just race straight up the I-5 corridor. This wind also affects the Northwest Interior, so it's a double whammy for you and another reason why wind events last so much longer up there.

And this upcoming storm is no different to where, say, Whidbey Island will see strong winds from roughly late Monday evening to 9 a.m. while the Puget Sound area is likely more limited to the 5-9 a.m. frame.

Do we ever dry out?

Only eight more months to SeaFair!

But since it is November, the answer in the short term is... no. The storm passes by midday Tuesday, and we'll all calm down again. But lo and behold, a third storm is looming for late Wednesday into Thursday now. This might bring a third round of wind on par with these two, but we'll keep an eye on it.

A series of storms continues to move through over the weekend and into early next week. Some long range models are trying to shift the West Coast into a drier pattern over Thanksgiving, but others keep it still kinda wet, if not as stormy, next week.