The National Weather Service has issued a high surf warning for beaches in Coos, Curry and Douglas counties from 10 a.m. Friday through 10 p.m. Saturday.
A strong cold front will move through the region before a large, long-period swell reaches the coast. Offshore swells could grow to 30 feet, producing breaking waves between 30 and 35 feet in the surf zone.
Lead meteorologist Joe Guerrero said the wind will arrive first, followed by the largest waves.
“The very high breaking waves, the 30- to 35-foot breaking waves along the shore, that’ll be for Friday evening and Friday night into Saturday morning,” Guerrero said.
The waves could inundate beaches, wash over dunes and accelerate coastal erosion. The Weather Service says they could also surge into normally dry areas and damage coastal infrastructure.
Guerrero has worked for the Weather Service for 16 years and has spent more than three years at its Medford office. He said waves of this size are infrequent but not unprecedented on the Oregon Coast.
“Since I’ve been here in the last three years, I’ve not seen waves this large,” Guerrero said. “The largest I’ve seen before this was 25 to 30 feet.”
The agency is urging people to stay off beaches and away from jetties, rocks, cliffs and driftwood. Guerrero said the storm will exacerbate the sneaker-wave hazards that are already common during the winter.
“The Pacific is just really brutal,” Guerrero said. “When we have a system like this coming through, it just compounds that.”
Dangerous surf has already required one rescue in Curry County this week. On Sunday, waves swept a woman off Secret Beach north of Brookings.
The approaching storm will also bring powerful winds. The Weather Service forecasts gusts approaching 65 mph near the coast and on exposed headlands. The strongest winds are expected Friday morning between Coos Bay and Pistol River.
The agency says trees and power lines could fall, causing outages and difficult travel along Highway 101. Guerrero advised residents to secure loose outdoor objects and prepare for possible power outages.
Coast Guard warns mariners to stay in port
Conditions at sea could be even more severe. The Weather Service upgraded its marine forecast Thursday afternoon, placing southern Oregon coastal waters under a storm warning through Friday morning. A gale warning will follow Friday afternoon.
Chief Warrant Officer Kevin Smith, commanding officer of Coast Guard Station Coos Bay in Charleston, said winter storms are familiar to local mariners, but this one is more severe than the ordinary bouts of rough weather.
“We do have rough conditions pretty continuously, but a storm this size, we only get maybe two or three times a winter,” Smith said.
The Coast Guard began restricting smaller recreational and passenger vessels from crossing the Coos Bay bar Thursday. At the time Smith spoke with JPR, recreational vessels 40 feet and shorter and uninspected commercial passenger vessels 36 feet and shorter were restricted.
Smith said those restrictions would likely expand to cover all recreational and uninspected passenger vessels. The Coast Guard could close the bar to all commercial traffic if conditions deteriorate further.
The station uses 47-foot motor lifeboats for search-and-rescue operations. Smith said those boats are limited to seas of 30 feet, breaking surf of 20 feet and sustained winds of 50 knots. If conditions exceed those limits, the station’s boat crews would be unable to respond, and rescues would rely on U.S. Coast Guard Air Station North Bend, which operates five MH-65 Dolphin helicopters..
“The helos from Air Station North Bend would be the only available asset,” Smith said.
Smith urged boaters in port to remain there and advised mariners already at sea to wait before attempting to cross the bar.
“Our general messaging to mariners is to avoid these conditions in their entirety and delay departure until the storm passes,” Smith said. “For mariners that are already out at sea, I would avoid coming into the harbors and stay at sea until the storm passes.”
Surf heights could decline somewhat Saturday night, but another large swell is forecast Sunday. Dangerous beach and marine conditions could persist into Monday.
Bar restrictions can change quickly. Mariners should check the latest conditions with the Coast Guard before attempting a crossing. In an emergency, mariners can reach the Coast Guard on VHF radio Channel 16.
