Bombogenesis’ slamming into Washington Tuesday

‘A “bomb cyclone” is forecast to hit Western Washington early Tuesday afternoon.

The National Weather Service has the High Wind Warning for gusts to 50-65 miles per hour including the towns of Queets, Aberdeen, Hoquiam, and Forks.

Also, areas along the western Strait of Juan de Fuca like Neah Bay could also see very strong east wind to 55-65 miles per hour gusts as these east winds shoot through the Strait out to sea. Boaters should avoid being in the Strait Tuesday evening and Tuesday night as winds in the center waters will be extreme and Storm Watches are in effect.

The coast is also under the High Wind Warning as they are closer to the storm with no buffer to stop the east winds with gusts to 50-65 miles per hour possible, it’s just the coast is more built for wind. Also some models keep the storm just far enough away so that the coast doesn’t get severe wind, just don’t go very far offshore.

The Westport Marina was warning boaters to check all their tie up lines, make sure pumps are working properly and to secure any loose items or gear on your vessel or the dock.

“‘Tis the season for storms, folks!,” the marina stated on its Facebook page. “And this one sounds like it may be a big one.”

Grays Harbor County Emergency Management stated the latest from the US National Weather Service Seattle shows the worst of the storm staying off the coast.

“We are still anticipated to see strong east to southeast winds Tuesday night into Wednesday morning. Near high surf conditions are also anticipated along our coast,” Grays Harbor County Emergency Management stated.

Meteorologist Scott Sistek forecasts the coast of Washington state won’t receive the brunt of the storm.

A High Wind Watch is in effect from Tuesday evening through late Tuesday night. Damaging winds could blow down trees and power lines. Widespread power outages are possible. Travel could be difficult.

“Well, things are starting to look a bit more ornery for this storm Tuesday evening into Tuesday night,” Sistek said. “The higher resolution forecast models are suggesting that the east winds coming out of the mountains will be strong enough to sweep across more of Western Washington and reach farther west than typical east wind events do and now the I-5 corridor may get more windy than earlier expected, especially from Seattle north through Everett and into Bellingham.”

However, the focus should remain on the foothills as they are still the areas looking to deal with the most severe wind gusts and impacts, he said, adding the warning “do not go into the mountains as blizzard warnings” are in effect for the Cascades for snow of up to a foot and winds up to 60 miles per hour.

“I suspect the passes may close Tuesday evening and night,” he said.

A High Wind Warning is in effect for the Cascade foothills, Bellevue area, the coast and western Strait of Juan de Fuca for that time frame. A Wind Advisory is now in effect for the rest of Western Washington including Seattle, Tacoma and Everett now and all other areas outside the current Wind Warnings.

When are the worst winds?

East winds will begin picking up around 4-5 p.m. Tuesday with the peak winds from 7 p.m. through about 1 a.m. then easing through the predawn Wednesday hours.

What’s happening?

A low pressure center that is still in its infant stages Monday morning will undergo “bombogenesis” — a term when a cyclone undergoes rapid intensification in 24 hours and this storm will easily qualify. “Bombogenesis” is also where the term “bomb cyclone” comes from.

Why does this matter?

The center of the storm will still stay hundreds of miles offshore and not get close to the coast. So we are dodging a Columbus Day Storm-type widespread damaging windstorm as if a storm that size came close to shore or, even inland. But even at arm’s length, it’s so strong its effects will still be felt across the Pacific coast — mainly for creating incredible differences in pressure across the Northwest, Sistek said.

“It’s like we’re a star system on the edge of a black hole — enough to feel the tug, but not close enough to get pulled into it,” he said.

Since the storm will be roughly due west of the coast, the storm will want to draw winds from the east to fill this massive low pressure drop.

“If Washington were flat, the winds would scream east to west everywhere but would be more spread out and not as intense,” he said. “But we’re not flat. The Cascades form a damming block that works well to protect much of Western Washingto from these kinds of winds except where there’s holes in the barrier — you know them as the mountain passes. Great for driving through; terrible for preventing wind leaks.

Who will get the strongest winds?

These gaps will allow wind to shoot through and accelerate and this is where we expect our strongest winds gusting to 55-65 mph with higher gusts — towns along and near the gaps, especially I-90 (Snoqualmie Pass), U.S. 2 (Stevens Pass) and SR 410 (Chinook Pass). That would be places like Enumclaw, North Bend, Black Diamond, Maple Valley, Cumberland and to the north, Index, Gold Bar, and to a lesser extent, Monroe.

Places along those highways farther west will also see strong winds, but not along the upper end wind speeds as the winds fan out a bit. Kent/Covington, Issaquah, Sammamish, Factoria parts of Bellevue near I-90, Sahalee, Newport Hills.

Strong winds will likely make it even over to South Seattle/SeaTac/Normandy Park but more like 45-55 mph gusts.

“I would plan on several power outages along the Eastern foothills and be wary of tree falls,” he said. “It’s your first big wind event of the year and it’s been a few years since I can remember the last really good east wind event up there. But longtime residents of foothills know what these east wind events are capable of.”

When will these winds end?

Looks like damaging wind gusts will abate by about 2-3 a.m. Wednesday morning.

Bottom line, if you can be home by dinner Tuesday best just to not travel, especially in the High Wind Warning areas. It’ll be dark by the storm time too.

What’s next?

We’ll be keeping an eye on Friday. A new not-as-strong low seems to want to spawn off our mega low that would be at least closer to a more traditional windstorm track but so far, long range models haven’t really keyed into a consistent track or strength of the storm. Nothing alarming yet but we’ll see what the models think as the day gets closer, Sistek said.