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Cliff Mass is sounding the alarm on his blog, about some pretty serious weather incoming from the Pacific:

Starting Thursday, we will enter a period of extraordinarily active weather with the potential for heavy rain, flooding, and a highly dangerous windstorm with the potential to be an historic event. The coastal waters and shoreline areas could well experience hurricane-force gusts, with a lesser but serious threat for strong winds over the interior. Keep in mind that there is still uncertainty in the forecasts, more so for the wind than the rain.

I have no more insight into the likely impact of these storms than the average STB reader, but disruption and delay to all modes of travel in Western Washington seems certain, and the Puget Sound Friday freeway commute, in particular, is probably something you’ll want to avoid if you can. On the coasts of Washington and Vancouver Island, rain will be torrential, and wind gusts may approach hurricane force, so nonessential travel anywhere near there should be avoided.

Keep an eye out for updates from the National Weather Service and local agencies (WSDOT, King County Metro, Sound Transit, Pierce Transit, Intercity Transit, Community Transit). My favorite reading in these situations is the detailed local synopsis put out four times daily by the NWS.

8 Replies to “Storm Warning for Friday and Saturday”

  1. Let’s talk about I-732 in the same sentence as ST-3, Eric. Both legitimately belong in the National Defense budget. Lose your immune and circulatory systems, and you don’t keep shooting very long.

    Mark Dublin

  2. Along with OneBusAway, a Seattle transit rider will want some sort of Doppler weather app for one’s phone. It is so helpful to see an approaching storm on an app and plan accordingly when on foot or transit. I use the Raindar app.

  3. Thursday night’s storm is a slam dunk in terms of forecast confidence that we’ll see a wind storm; but it’s still not clear whether this is a “once per season” magnitude of windstorm or if it’s going to be a bit stronger than that. If the low center tracks over the tip of the Olympic Peninsula then winds will be much stronger than if it stays 50 miles off the coast. Regardless, expect fairly widespread power outages, especially since leaves are still on the trees (this is the “sail” effect). Winds should start picking up in earnest around 5pm, so you might regret staying a few minutes late at your desk. Saturday night’s storm is truly eye-popping. The track of the storm is everything, and models haven’t come into agreement. There is good reason for the high uncertainty: the storm is currently transitioning from a “tropical” storm (a super-typhoon, in fact) which means its energy source is warm water at the surface, to a mid-latitude storm with an energy source of temperature *gradient*, which is at altitude (the jet stream). So…it’s currently near Japan, being swooped up by the jet stream, and will fly across the ocean as a weak, moist disturbance until it hits the right conditions off our coast, where it will explosively intensify over 18 hours and turn north as it reaches its peak. Any initial small errors in the forecast would grow exponentially (in time) in a case like this, hence the uncertainty. If it turns north while tracking along our coast, we get Columbus Day Storm 1962 type damage. If it turns north and stays a couple hundred miles from our coast, then we *just* get, say 50mph wind gusts in Seattle, but still 35-45ft waves and much stronger winds at the coast. Chance of an historic (once per decade or less) storm: 1 in 3. Chance of a catastrophic just-shy-of-Columbus-Day storm: 1 in 6. So at this point it’s a 2-in-3 chance that it’s similar to or a bit stronger than Thursday’s storm, but…1-in-6 is still definitely a number to keep and eye on. This is a rare event regardless of whether the track is perfect to be catastrophic for us. Once the storm has finished its extra-tropical transition we can hope to see consistency between models and consistency between successive runs of the same model, and then we’ll have much more confidence. Give it another 36 hours and maybe we’ll have a better idea, but prepare now just in case.

    -A meteorologist and STB regular reader

  4. We’ll definitely see some outages in greater Seattle, but even I’m uncertain as to how the Link catenary or the Metro trolley wires are gonna hold up despite its separation from the regular grid.

    1. In past storms, it seems the biggest issues have been trees knocking the lines down. I don’t know that Link has a lot of trees near its lines since its above-ground segments are either elevated or center running in a wide roadway. It is unfortunate that there is no turnback at the south tunnel portal since that would allow them to run trains entirely below ground if there were an extended power outage at the maintenance yard.

      As for the trolley routes, now that Metro operates trolleys that can go off wire it might not be as huge of an impact as it used to be, though obviously still disruptive.

      1. Link itself will probably be ok, but the feeders to various substations may go dead. Also, underground vaults could fill up with water due to severe water intrusion.

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