Friday ice storm could bring chaos to South Sound. Utilities are gearing up to respond

An ice storm headed for western Washington Thursday evening was expected to create travel headaches for holiday travelers along with a host of other problems.

High pressure over eastern British Columbia and low pressure over western Washington was sucking arctic air into the region. That, combined with other weather conditions, is setting the stage for an ice storm.

The National Weather Service’s Seattle office issued a winter storm warning for the area starting at 4 p.m. Thursday until 7 p.m. Friday.

What is an ice storm?

An ice storm begins as snow at the higher levels of a weather system. As the snow falls it passes through a layer of warm air and becomes rain. When the rain nears the ground it comes into contact with a layer of cold air.

The result, said National Weather Service meteorologist Dev McMillian, is rain that turns to ice when it hits just about any surface: asphalt, roofs, trees, sidewalks, train tracks, power lines, cars and airplanes.

“That can definitely disrupt travel,” McMillian said. “And it can also weigh down trees, do a number on utility lines. It can really disrupt power for an extensive amount of time depending on the severity.”

Pierce and Thurston counties could see between one-tenth and one-quarter inch of ice — enough to turn the trip to grandma’s house or walk around the neighborhood into a miserable experience.

Windy conditions will be enough Thursday evening to bring windchill to western Washington, making it feel like 5-15 degrees, the National Weather Service said. Wind gusts could reach 15-20 miles per hour in Tacoma and Olympia.

Power outages possible

Area utilities were bracing for a major ice event.

Rebekah Anderson, media representative for Tacoma Public Utilities, told The News Tribune via email, “All our crews are available and we’re monitoring info from the Weather Service.”

In outages, TPU’s emergency response goes in descending order to reach the greatest number of customers as soon as possible. It includes performing initial assessment, repairing transmission lines, then substations, then feeder lines, then finally tap lines, which move power from feeder lines to individual streets.

As for restoration, “Public health and safety facilities, such as hospitals, clinics and utilities get first priority,” Anderson said.

She also warned against “cold load,” when the grid is hit with high demand “as we try to re-energize areas that have been without power for a long time.“

“When customers leave appliances on during an outage, the heavy, immediate demand on a re-energized system can sometimes cause a secondary outage as circuit breakers trip to protect the system from overload,” she wrote.

She advised that to prevent a second outage after restoration in a widespread outage, customers can turn off the breaker switch to their “furnace, water heater and large appliances during a long-term power outage.

“When electricity is restored, they can further help by turning on electronics and large appliances slowly, one by one,” Anderson said.

Andrew Padula, media representative for Puget Sound Energy, told The News Tribune that his company had prepped and was organizing for extra crews.

“At this point, we are calling contract crews to check their availability so we can supplement out crews as needed, calling in extra system operators, bringing dispatchers in early and watching for weather updates. We have crews ready to respond if and when an outage occurs,” Padula said.

He added, “We are pre-emptively staffing up our command center (System operators/Dispatchers) so we can respond rapidly if the freezing rain does come to fruition.”

With the uncertainty of both snow and ice in the forecast, he said, the utility recommended people prepare for an outage that could last “possibly for an extended time. We know this is frustrating and disruptive to holiday plans and we will be working around the clock to respond.”

Outage maps

▪ Peninsula Light: penlight.org/power-outages/outage-updates/

▪ TPU: mytpu.org/outages-safety/power-outages/

▪ PSE: pse.com/outage/outage-map

Driving hazards

The state Department of Transportation was preparing for the ice storm on Thursday by treating state highways with a salt brine, said spokesperson Cara Mitchell.

“Freezing rain, ice storms are one of the most challenging weather conditions to try to prepare for,” Mitchell said. “And so we’re treating everything right now. And we will adapt as the conditions change.”

Mitchell urged drivers to be prepared whether they are going across town or over mountain passes.

“I would really encourage drivers to pay attention to the pass conditions and the chain requirements,” she said. In poor conditions, even four-wheel-drive vehicles are required to put chains on.

WSDOT’s website will have the latest pass and road conditions. Drivers are urged to gas up, carry blankets and prepare for challenging conditions.

▪ WSDOT: wsdot.com/travel/real-time/

Air travel

Seattle-Tacoma International Airport was a mess Thursday, with a security breach shutting lines down for about 15 minutes and forcing security lines out into the terminal garage amid the frigid weather.

The minor breach was caused by someone passing through a checkpoint without a proper badge, according to KING-TV.

The airport tweeted after 7 a.m., “The breach has been cleared, however wait times have increased.”

Long lines continued through the morning as the effect of the brief shutdown was compounded by high numbers of travelers.

In a social media post Dec. 21, the airport said it expected the number of travelers for the holidays to be back at “pre-pandemic levels,” with the busiest days routinely Thursdays and Fridays “as well as Sundays and Mondays,” and TSA security checkpoints busiest “from 5-10 a.m., 2-5 p.m., and 9-11 p.m.”

Passengers can check flight status at portseattle.org/sea-tac/flight-status or directly with your airline. Global real-time flight status updates are at flightaware.com

Sea-Tac officials have advised travelers coming to the airport to dress warmly in case further backups again force people to wait outside the terminal.

The days ahead

Friday’s freezing rain will eventually give way to just rain. Temperatures will increase dramatically into Saturday with a new storm system arriving.

The Weather Service advised Thursday that a series of atmospheric rivers will impact all of western Washington through Monday. River flooding is likely through early next week.

Unusually high tides — king tides — might cause minor tidal overflow by Saturday.

Avalanche danger will increase in the mountains.