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.

The two bars get zones of their own, separate from the water either side of them, because a bar behaves like nothing else nearby.

Eight towns on this coast do not open onto the ocean at all, and the Strait is three forecasts before it becomes a fourth water. Neah Bay, Sekiu and Clallam Bay read PZZ130, the west entrance; Joyce and Port Angeles read PZZ131, the central Strait; Sequim reads PZZ132, the east entrance; and at Point Wilson the Strait turns south into PZZ134, Admiralty Inlet, which is Port Townsend's and Port Hadlock's water and is tide-driven in a way none of the others are — the whole of Puget Sound fills and empties through it twice a day. The lines are the weather service’s own, and each town’s was settled by sending the water off it to the marine zone layer rather than by reading a map. It matters most in a westerly: the fetch down the Strait builds eastward, so the east entrance can be rough while the west is merely windy, and the other way about on a flood tide. All three are a different sea from the one a mile round Cape Flattery: shorter, steeper, and driven as much by the ebb running against a westerly as by the swell. A boat crossing from the Strait to the ocean is crossing between two forecasts, and both are on the board.

The north Sound is one zone from the border to Deception Pass. Every Whatcom town — Point Roberts on the Strait of Georgia, Blaine and Birch Bay, Ferndale on Lummi Bay, Lummi Island and Bellingham Bay — reads PZZ133, “Northern Inland Waters Including The San Juan Islands”, which is Seattle’s one forecast for the whole of the water north of Whidbey and east of the islands. Asked at a point off each of the six towns, the weather service’s own zone layer answered PZZ133 every time. It is an inland-waters product on the inland cycle, like Admiralty Inlet’s and Hood Canal’s, and it is coarse in the same way: a northerly down the Strait of Georgia that has Point Roberts white-capped can leave Bellingham Bay flat behind Lummi Island, and the forecast is one sentence for both. The islands and Skagit read it too: water off Friday Harbor, Orcas, Eastsound and Lopez, and Samish, Padilla and Skagit bays, all answered PZZ133 on 2026-09-20, so every town from Point Roberts to La Conner is under the one forecast. Island County joined on 2026-09-20 and most of it reads the same zone: Oak Harbor, Coupeville on Penn Cove, Freeland, Langley and Camano Island. Clinton is the exception — Possession Sound is PZZ135, the Puget Sound product, and the Clinton ferry crosses it. South of there the board is all PZZ135. Snohomish’s shore from Tulalip to Edmonds answered it on 2026-09-20 (Stanwood, at the head of Port Susan, stays on PZZ133), and every King County pin — Shoreline, Seattle, West Seattle, Burien, Des Moines, Federal Way and Vashon — answered it on 2026-09-21, and so did all ten of Kitsap’s the same day, Hood Canal off Seabeck included. Pierce County joined on 2026-09-21 and did not add a zone either. The south Sound’s inlets are narrow enough that the weather service’s zone layer returns the LAND zone at a point off Steilacoom, Longbranch or Anderson Island rather than a marine one — the same answer Bremerton and Poulsbo gave — so all nine Pierce towns read PZZ135, the open Sound, which is the water they launch into. It is worth knowing that a forecast written for Admiralty Inlet and Seattle is being read at Filucy Bay, forty miles south. Thurston County joined the same night and every one of its five pins — Budd, Totten and Henderson inlets and the falls at Tumwater — answered PZZ135 too, so the one product now runs from Point Roberts to the very end of the Sound. Mason County finished the job the same night: Hood Canal’s west shore from Lilliwaup round the Great Bend to Belfair, and Case Inlet and Oakland Bay, all PZZ135 — the product has “Hood Canal” in its name, and the canal is the one place on the board where that name is all a reader gets, with no station on the water to check it against. It is one sentence for the whole main basin, Hood Canal included: a southerly that has Elliott Bay standing up can leave Quartermaster Harbor flat, and the forecast will not tell you which.

And south of the Hood Canal bridge the forecast gets coarser, not finer. Quilcene and Brinnon read PZZ135, “Puget Sound and Hood Canal” — one product for the whole inland sea, from Olympia to Everett and the length of the canal. It is the only marine forecast the weather service issues for that water, so it is the one the board carries, but it is worth knowing what it is: a wind that fits Puget Sound may not be the wind in a forty-mile trench with the Olympics on one side of it. Hood Canal funnels southerlies and northerlies along its own axis and can be calm at Quilcene while it blows at Brinnon, or the reverse. Read the zone, then look out the window.

The line between PZZ150 and PZZ153 runs at James Island, which stands at the mouth of the Quillayute at La Push. The water a boat crosses leaving La Push is PZZ150; a mile south of the island it is PZZ153.

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:

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 weather service 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