How to Read Tide Charts for Salmon Fishing in the Pacific Northwest

Published by DriftLine | The Outdoor Intelligence App for the Pacific Northwest

What Is a Tide Chart and How Do You Read One?

A tide chart is a visual representation of predicted water levels over time. The horizontal axis is time (usually a 24-hour or multi-day window), and the vertical axis is water height, measured in feet above a reference datum called Mean Lower Low Water (MLLW). The result is a smooth, undulating curve that shows you exactly when water will be rising, falling, or transitioning between the two.

Every coastal location experiences roughly two high tides and two low tides per day, though they are not equal. The Pacific Northwest sees what oceanographers call "mixed semidiurnal" tides — two highs and two lows per tidal day (approximately 24 hours and 50 minutes), but with one high notably higher than the other and one low notably lower. This matters for fishing because the stronger tidal exchanges produce stronger currents, which directly influence fish behavior and feeding activity.

The key elements to identify on any tide chart:

• High Tide: The peak of the curve. Water level is at its maximum.
• Low Tide: The trough of the curve. Water level is at its minimum.
• Tidal Range: The vertical difference between a given high and the adjacent low. A range of 8-10 feet produces significantly different fishing conditions than a range of 4-5 feet.
• Flood Tide (Incoming): The rising portion of the curve, when water flows from the ocean into bays and estuaries.
• Ebb Tide (Outgoing): The falling portion of the curve, when water flows from bays and estuaries back toward the ocean.
• Slack Water: The brief inflection points at the top and bottom of the curve where current effectively stops before reversing direction.

NOAA publishes free tide predictions for hundreds of stations along the Pacific Coast. These predictions are based on harmonic analysis of historical tidal data and are remarkably accurate under normal conditions. Wind, barometric pressure, and river discharge can cause actual water levels to deviate from predictions, but the timing of tide changes remains reliable.

When reading a tide chart, do not just look at the highs and lows. Study the steepness of the curve between them. A steep slope means water level is changing rapidly, which translates to stronger current. A gradual slope means a gentler transition. The steepest portions of the curve — roughly the middle third of a flood or ebb cycle — produce the strongest currents. The flattest portions — near the peaks and troughs — are where you find the productive slack water windows.

Slack Tide, Spring Tides, and Neap Tides — What Matters for Fishing

Three concepts separate anglers who understand tides from those who merely check them.

Slack Tide

Slack tide is the brief window when tidal current effectively stops before reversing direction. It occurs near — but not exactly at — each high tide and low tide. This distinction trips up a lot of anglers. The tide chart shows water level. Slack water refers to current velocity. In large estuaries and river mouths, high tide and high slack can differ by up to three hours because the massive volume of water takes time to stop moving even after the level has peaked.

High slack (the pause near high tide) is almost universally the most productive fishing window in tidal waters. Baitfish relax, predators stage for the coming ebb, and the water column is at its deepest — which compresses fish into predictable zones near structure. Low slack has its uses too, particularly for exposing structure and identifying holding water you will target on the next flood.

Spring Tides

Spring tides occur during new moon and full moon phases when the sun and moon align gravitationally. The name has nothing to do with the season — it comes from the old Germanic word meaning "to leap." Spring tides produce the largest tidal ranges of the month: higher highs, lower lows, and significantly stronger currents between them. A location that normally sees a 6-foot tidal range might see 9 or 10 feet during spring tides.

For fishing, spring tides are a double-edged sword. The stronger currents push more baitfish, stir more nutrients, and trigger more aggressive feeding behavior. But they also make boat control harder, reduce the effective duration of slack water windows, and can make certain spots unfishable. At places like the Columbia River mouth, spring tide currents can exceed 5 knots — enough to make anchoring difficult and trolling impractical in certain zones.

Neap Tides

Neap tides occur during first quarter and last quarter moon phases when the sun and moon are at right angles relative to Earth. They produce the smallest tidal ranges: modest highs, modest lows, and gentle currents. A spot with a normal 6-foot range might see only 3-4 feet during neaps.

Many experienced PNW anglers actually prefer neap tides. The gentler currents extend the productive slack water windows, make boat control easier, and — critically — often produce clearer water. In places like Tillamook Bay, small tidal exchanges during neap tides let returning salmon smell the outgoing river water without having to fight a punishing current. The fish can take their time staging and entering the system, which concentrates them in predictable holding areas.

Incoming vs. Outgoing Tide — Which Is Better for Salmon?

This is the question every new tidal angler asks, and the honest answer is: it depends on your technique.

Trolling and Incoming Tide

If you are trolling — whether pulling herring, spinners, or plugs — an incoming (flood) tide is generally your friend. The incoming current opposes your boat's movement when trolling seaward, which means your gear is working harder at slower trolling speeds. You get better action on your lures, more natural bait presentation, and you cover water where salmon are actively moving.

During the incoming tide, salmon tend to suspend in the water column. They are riding the flood tide into estuaries and river mouths, using the current to conserve energy — essentially surfing the tide inland. Suspended fish are trolling targets. They are off the bottom, actively moving, and interceptable at predictable depths.

Plunking and Outgoing Tide

If you are plunking (bank fishing with weight on the bottom) or still-fishing from an anchored boat, the outgoing (ebb) tide is often more productive. The current flowing past your stationary gear does the work for you — it activates spin-n-glo lures, flutters bait, and carries scent downstream. Your presentation is fishing itself while you wait.

During the ebb, salmon tend to hold closer to the bottom. The dropping water level compresses available habitat and pushes fish into deeper channels and depressions. Bottom-oriented presentations reach these fish directly.

The High Slack Sweet Spot

Across nearly all techniques, the transition period around high slack — from about 30 minutes before high tide through the first 60 to 90 minutes of the ebb — is the most consistently productive window. Water depth is at its maximum, current is minimal, and salmon that rode the flood tide in are now settling into holding positions as the ebb begins. This is when the river "turns over," and it frequently triggers a burst of feeding activity.

Anchoring

Anchor fishing in tidal water demands awareness of current direction and intensity. Many anchor spots only fish well on one tide phase because the current must carry your bait or lure into the strike zone. Know your spot. Fish it on the correct tide. Do not fight the system.

How Tides Affect Salmon Movement in PNW Rivers

Tidal influence reaches far beyond the beach. The Pacific Ocean's gravitational pulse pushes up the Columbia River approximately 145 river miles to Bonneville Dam. On the Willamette River, tides are measurable all the way to Oregon City Falls, 26 river miles upstream from the confluence with the Columbia. These are not trivial effects — water levels in Portland can fluctuate 2 to 3 feet with the tides, and current direction actually reverses in the lower stretches during strong flood tides.

Salmon evolved to exploit this system. Returning adults ride incoming tides upstream, conserving energy the way a surfer rides a wave. When the tide turns and the ebb begins, they duck behind structure — bridge pilings, rock ledges, channel edges — and hold position until the next flood pushes them further upriver. This "two steps forward, one step back" migration pattern means fish stack up in predictable holding water on predictable tide phases.

For the angler, this creates opportunity. If you know where the holding water is and when the tide turns, you can be in position when fresh fish arrive and settle in. The lower Columbia from Astoria to the I-5 bridge, the Willamette from the mouth to Milwaukie, and the lower reaches of coastal rivers like the Tillamook, Siuslaw, and Coos — all of these fisheries are fundamentally tide-driven. Fishing them without understanding the tidal cycle is fishing blind.

Even in the upper tidal reaches where the effect on water level is measured in inches rather than feet, the subtle change in current velocity can trigger or suppress bites. Salmon have lateral lines exquisitely sensitive to water movement. They know when the current eases. You should too.

Tide Strategies for Buoy 10 and Columbia River Fishing

Buoy 10 — the fishery at the mouth of the Columbia River between Astoria, Oregon, and Ilwaco, Washington — is the marquee tide-dependent salmon fishery in the Pacific Northwest. Thousands of boats converge here every August and September to intercept returning Chinook and Coho as they enter the river. Tide literacy is not optional at Buoy 10. It is the single biggest factor in whether you limit out or go home empty.

The Proven Window

The most productive tide phase at Buoy 10 is high slack through the first half of the ebb. This typically provides a 2- to 3-hour fishing window that accounts for a disproportionate share of the catch. Here is what happens during that window:

1. Late Flood: Salmon push upriver on the incoming tide. The fleet positions along the edges of the navigation channel and in the transition zones between river current and tidal flow.
2. High Slack: Current drops to near zero. Fish that were actively migrating slow down and become more willing to strike. Trolling speed becomes your boat speed alone, giving you complete control over presentation.
3. Early Ebb: The tide turns. Fresh saltwater begins mixing with river water, creating scent lines and turbidity breaks that concentrate bait and predators. Salmon that were pushing upriver now face opposing current and hold near structure and channel edges. This is prime time.

Tactical Notes

• Troll with the ebb in the early outgoing phase. Position your boat to troll upriver (against the ebb current) so your gear moves slowly relative to the water while covering ground over fish that are now holding or slowly retreating.
• Watch the rip lines. Where outgoing river current meets incoming ocean swell, visible rip lines form. These are structure in open water. Fish them.
• Adjust depth aggressively. Fish may be at 15 feet during high slack and 45 feet two hours later as the ebb pulls the thermocline down. Use your electronics and do not assume yesterday's depth works today.
• The second tide can produce a second, smaller bite window. If morning slack was the primary window, the afternoon flood may push a new pulse of fish in. Many anglers leave after the morning ebb slows. The persistent ones sometimes get rewarded.

Planning Your Day

Check the tide chart the night before. Identify the time of high slack and work backward. You want lines in the water at least 45 minutes before high tide. If high slack is at 9:00 AM, plan to be fishing by 8:15 and expect the primary window to run until roughly 10:30 or 11:00. Build your morning — launch time, travel time, prep time — around that window.

Best Tides for Crabbing, Surf Perch, and Other Coastal Species

Tides are not just a salmon game. Nearly every species you pursue in saltwater or tidal estuaries has a tidal preference.

Crabbing

Best tide: High slack. Dungeness crab are active foragers, but they hunker down and stop moving during periods of maximum current. Strong ebb or flood tides also make your pots less effective — the current pushes bait scent in a narrow, fast-moving plume that crabs have difficulty following, and pots can tip or drag. At high slack, current is minimal, bait scent disperses in a wide radius, and crabs are on the move. Drop your pots 30 to 60 minutes before high slack and pull them 60 to 90 minutes after. Maximum ebb is the worst time to have pots in the water.

Surf Perch

Best tide: Incoming, 1-2 hours before high. Surf perch feed in the wash zone where waves dislodge sand crabs, clams, and other invertebrates from the sand. As the tide comes in and waves push higher up the beach, fresh sand is exposed and prey gets tumbled loose. The hour or two before high tide concentrates perch in a narrow, fishable band of churning water close to shore. Fish sand crabs or Berkley Gulp sandworms on a sliding sinker rig and cast just beyond the breakers.

Halibut

Halibut in PNW estuaries (particularly the Columbia River and Tillamook Bay) respond to moderate current. Dead slack can actually slow the halibut bite because your bait sits lifeless on the bottom. A gentle ebb or early flood that keeps your herring or spreader bar bouncing naturally often produces better than the slack window itself. Target the transition periods — the first and last hour of each tide phase — rather than the exact slack.

Rockfish

Tide matters less for offshore rockfish sitting in 120 feet of water, but for nearshore lingcod and black rockfish, the incoming tide pushing baitfish against rocky structure creates feeding opportunities. Fish the last two hours of the flood for kelp-edge lingcod.

How Moon Phases and Barometric Pressure Influence Bite Windows

Tides do not exist in isolation. They are driven by the moon, and the moon's influence on fish behavior extends beyond just water movement.

Solunar Theory

Solunar feeding theory holds that the moon's position relative to a given location creates four daily feeding windows: two major periods (roughly 2 hours each, centered on the moon's transit overhead and underfoot) and two minor periods (roughly 1 hour each, centered on moonrise and moonset). New and full moons — when tides are also at their strongest — produce the most intense feeding activity.

Is this proven science? Not definitively. But decades of catch logs from serious anglers show a correlation strong enough to pay attention to. When a major solunar period coincides with a favorable tide phase (especially high slack), the result can be explosive fishing. When they conflict — say, a major solunar window falls during maximum ebb — the tide phase usually dominates.

Barometric Pressure

Barometric pressure affects fish through their swim bladders, the gas-filled organs that control buoyancy. When pressure drops (ahead of a weather front), the swim bladder expands, creating discomfort that many biologists believe triggers feeding as fish attempt to equalize. Fish with proportionally large swim bladders — salmon, trout, steelhead — are the most sensitive.

The practical pattern:

• Falling pressure (pre-front): Aggressive feeding. This is the "fish before the storm" window that experienced anglers swear by. It is real.
• Low, stable pressure (during a storm): Fishing generally slows. Fish have adjusted to the low pressure and are hunkered down.
• Rising pressure (post-front): A gradual return to normal feeding patterns. The first day of rising pressure after a front can be excellent.
• High, stable pressure (clear weather): Consistent but not spectacular. Fish feed on regular patterns.

Combining the Variables

The best fishing days on the PNW coast stack multiple factors: a favorable tide phase (high slack through early ebb), a major solunar period, and falling or recently-fallen barometric pressure. These days do not happen every week, but when they align, seasoned anglers clear their schedules. Keeping a log of conditions alongside your catch data is the fastest way to identify which factors matter most at your specific fishing locations.

How DriftLine Makes Tide Intelligence Actionable

Everything discussed in this article — tide timing, tidal range, slack windows, moon phases — is data that DriftLine surfaces directly in the app so you spend less time cross-referencing charts and more time fishing.

DriftLine's tide station detail screens show predicted tide curves for any station along the Pacific Coast, with high and low tide times, heights, and tidal range clearly marked. You can scrub through multi-day forecasts to plan trips around the most favorable tide windows. The visual tide charts make it immediately obvious when slack periods fall and how steep the current transitions will be.

For Buoy 10 and Columbia River anglers, DriftLine's dedicated Buoy 10 dashboard brings together tide data, bar conditions, and river intelligence in a single view purpose-built for the fishery. Instead of toggling between NOAA tide tables, bar camera feeds, and river gauge data, you get the complete picture in one place.

The app also integrates moon phase data alongside tide predictions, so you can identify those high-value days when solunar feeding windows align with favorable tide phases. Combined with river flow data from USGS gauges and real-time weather, DriftLine gives you the full environmental picture — the same variables that experienced guides mentally juggle, organized and accessible from your pocket.

DriftLine was built by people who fish these waters. The features exist because we needed them ourselves.

Frequently Asked Questions

What is the best tide for salmon fishing?

High slack through the first half of the outgoing (ebb) tide is the most consistently productive window for salmon across most PNW fisheries. The pause at high tide lets migrating salmon settle, and the beginning of the ebb triggers feeding as current starts moving bait. Trollers should focus on the late incoming through slack; plunkers benefit most from the early ebb when current works their gear.

Does slack tide matter for fishing?

Yes. Slack tide — the brief pause when current stops between tide changes — is one of the highest-percentage fishing windows in tidal water. High slack is generally more productive than low slack. Current stops, fish reposition, and the transition triggers feeding behavior. In many estuaries, the 30 minutes before and after slack account for a disproportionate share of the daily catch.

How far upstream do tides affect the Columbia River?

Tidal influence extends approximately 145 river miles up the Columbia to Bonneville Dam, and 26 miles up the Willamette River to Oregon City Falls. In the lower reaches, water levels can fluctuate 2 to 3 feet and current direction can actually reverse during strong flood tides. Even in the upper tidal zone, subtle current changes affect fish behavior and feeding patterns.

What is the best tide for crabbing?

High slack tide is the best window for crabbing. Dungeness crab stop moving during periods of strong current and your pots fish poorly when heavy flow pushes bait scent into a narrow plume. Deploy pots 30 to 60 minutes before high slack and retrieve them 60 to 90 minutes after. Avoid having pots in the water during maximum ebb, which is the least productive phase for crabbing.

Do moon phases actually affect fishing?

Experienced anglers and decades of catch data say yes. New and full moons produce spring tides with stronger currents and appear to correlate with more aggressive feeding. Solunar theory identifies four daily feeding windows based on the moon's position — two major periods of about 2 hours and two minor periods of about 1 hour. The effect is most noticeable when solunar windows align with favorable tide phases.

What is the difference between tides and tidal currents?

Tides are the vertical change in water level — the rise and fall you see on a tide chart. Tidal currents are the horizontal movement of water caused by tides — the flow you feel in your anchor line or see in your trolling speed. They are related but not simultaneous. In large estuaries, high tide and high slack current can differ by up to 3 hours because the massive volume of water takes time to decelerate.

When is the best time to fish at Buoy 10?

Target high slack through the first 90 minutes of the ebb tide. This is the single most productive window at the Columbia River mouth fishery. Plan to have lines in the water 45 minutes before high tide. The typical primary window runs 2 to 3 hours. Watch for a secondary bite window on the afternoon flood tide, which can push fresh fish into the fishery.

Should I fish spring tides or neap tides?

Both have advantages. Spring tides (new/full moon) produce stronger currents that move more bait and can trigger aggressive feeding, but make boat control harder and shorten slack windows. Neap tides (quarter moons) offer gentler currents, longer slack periods, and often clearer water. In estuaries like Tillamook Bay, neap tides are frequently preferred because they let salmon stage comfortably without fighting punishing current.

Conclusion

Tides are not background noise in Pacific Northwest fishing — they are the primary engine driving fish behavior from the open coast to 145 miles inland. Learning to read a tide chart is the first step. Learning to match your technique, timing, and location to the tidal cycle is what separates consistent anglers from hopeful ones.

Start simple. Pick one fishery you know well. Fish it deliberately on different tide phases and log the results. You will see patterns emerge within a few trips. High slack will prove its reputation. You will develop preferences for spring tides or neaps based on your techniques and locations. The tide chart will shift from a confusing graph to the first thing you check when planning a day on the water.

The tides are free information. The fish are already using them. Now you can too.