Guide
Small craft advisories and the marine zones
Checked September 13, 2026 against the National Weather Service.
The Marine tile repeats the National Weather Service’s forecast for the strip of water your town opens onto. This page explains which zone that is, what the advisories and warnings actually mean in numbers, and the one line in the forecast that is most often misread.
This coast is forecast by two different offices
Washington’s ocean coast is split between two National Weather Service offices, and the boundary is Cape Shoalwater, at the mouth of Willapa Bay.
North of it — the Olympic coast and all of Grays Harbor County’s ocean frontage — is forecast from Seattle. South of it — the Long Beach Peninsula, the ocean side of Willapa Bay, Cape Disappointment — is forecast from Portland. That is counterintuitive if you live on the peninsula, and it is worth knowing when you go looking for a forecast discussion or a marine warning directly from an office.
The zones, and the ten-mile line
A coastal waters forecast covers “bays, harbors, and sounds, from a line approximating the mean high water mark” outward. Each stretch of this coast is split in two: an inner zone out 10 nautical miles, and an outer zone from 10 to 60, between the same two headlands. The inner zone is the one that matters for the surf, the bar and a small boat.
| Zone | Between | Office | Towns on this board |
|---|---|---|---|
| PZZ150 | Cape Flattery to James Island, out 10 nm | Seattle | |
| PZZ153 | James Island to Point Grenville, out 10 nm | Seattle | |
| PZZ156 | Point Grenville to Cape Shoalwater, out 10 nm | Seattle | |
| PZZ251 | Cape Shoalwater south, out 10 nm | Portland | North Cove, Tokeland, Raymond, South Bend, Bay Center, Oysterville, Nahcotta, Ocean Park, Naselle, Long Beach, Seaview, Ilwaco, Chinook |
| PZZ110 | Grays Harbor Bar | Seattle | |
| PZZ210 | Columbia River Bar | Portland |
The two bars get zones of their own, separate from the water either side of them, because a bar behaves like nothing else nearby.
What the words mean, in knots
These are thresholds, not moods. The National Weather Service publishes them:
- Small Craft Advisory. In the Western Region, which covers this coast: sustained winds or frequent gusts of 21 to 33 knots, and/or wave heights over 10 feet. “Small craft” is deliberately undefined — the service leaves it to you to know whether your boat and your experience are up to those conditions.
- Gale Warning. Sustained winds or frequent gusts “in the range of 34 knots (39 mph) to 47 knots (54 mph) inclusive.”
- Storm Warning. “48 knots (55 mph) to 63 knots (73 mph) inclusive.”
- Hurricane Force Wind Warning. “64 knots (74 mph) or greater.” On this coast that is a winter storm, not a hurricane.
- Special Marine Warning. Short-fuse, usually under two hours: sustained winds or gusts of 34 knots or more, or a thunderstorm, large hail or a waterspout, not already covered by the forecast.
For the Columbia River Bar specifically, the Portland office sets a small craft advisory at seas of 7 to 9 feet with strong tidal currents — a lower bar, on a shorter fuse, because that is what that water does.
The line most often misread
A forecast of “seas 10 feet” does not mean the waves are ten feet. Seas means significant wave height: “the mean or average height of the highest one third of all waves.” Two thirds of the waves are smaller than the number. Some are very much larger.
The service says so itself, and it is the single most useful sentence in its marine FAQ:
“Be aware that wave forecasts are an average. The height of some individual waves can be expected to be as much as two times greater. Reports of ‘rogue’ waves of even greater heights are not uncommon.”
So a ten-foot forecast is a forecast that includes twenty-foot waves. Read the number that way every time.
On the beach, not just on the water
The same swell that makes a marine forecast makes the hazard people on this coast are most often caught by. A sneaker wave is a wave that “surges further up the beach than expected, overtaking the unaware,” and the service notes there can be “10 to 20 minutes of small waves right before a sneaker wave strikes.” They can run at least 150 feet into dry beach.
The specific danger on Washington’s beaches is the driftwood. In the service’s words: logs on the beach “are wet, extremely heavy, and can weigh hundreds of pounds. Yet a single sneaker wave can lift and roll these logs further up the beach, as well as roll them back down the beach, knocking over or pinning unsuspecting beachgoers.” Stay off the logs, stay farther back than feels necessary, and never turn your back on the ocean.
When a long-period swell is running, the Portland office can issue a Beach Hazards Statement for exactly this, and a High Surf Warning when “the energy of the waves has hit a threshold that poses a serious risk to those on the beach.” There is no published swell period that triggers it, so this page does not invent one.
Sources
- National Weather Service Seattle, marine zones and National Weather Service Portland, marine zones — the zone numbers, names and the Cape Shoalwater boundary
- National Weather Service, marine forecast FAQ — the advisory and warning thresholds, and the caution about individual wave heights
- National Weather Service Portland, marine and coastal hazard criteria — the Columbia River Bar advisory and the beach hazard products
- National Weather Service, sneaker waves — including the logs