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What are Tides?

Tides refer to the gravitational pull of the sun and moon on bodies of water.  Depending on the alignment of the sun and moon, tides will vary from day to day.  Some tides cause the water level to drop or raise by as much as six or seven feet at a time.  Other tides may only move the water level a few feet at a time.  Some tides in the delta cause the river to flow downstream, become slack like a lake, and then move back upstream.  The next time somebody tries to bet you that water doesn't flow upstream, take them to the delta.  Pretty weird, huh?

Tides are one of the most important factors while fishing the delta.  The best bite window usually lasts from one hour before a tide change until one our after the slack tide.  This will usually give you a few hours of really good fishing.

As with all factors involved in fishing, predicting action using tides is not an exact science.  There will be days when the fish defy logic and bite during unexpected tides.  I've caught fish during all tides, and I've also been skunked during all tides.  I use the tides as a guide to plan my fishing trips around the times that I hope will be the most productive.

The tide links on this site will take to you pages that show when the tide is predicted to change.  Keep in mind that the tide changes shown on these links refer to the changes in tidal pull by the sun and moon, not water flow.  The change in current direction in the delta seems to lag about 30 minutes to one hour after the time shown as the tide change.  For example, if the high tide is shown as 10:00 am, the slack tide may not happen until 10:30 am or 11:00 am.  The tide changes shown are just predictions and can be affected by dam releases, rainfall, wind, etc.  For a technical explanation of predicting slack tide, see the rule of twelfths.

Outgoing Tide (Ebb Tide)

The outgoing tide moves downstream towards the ocean.  It is usually faster because it moves with the flow of water.  Because of its fast speed, it us usually dirtier and more prone to stir up weeds than the incoming tide.

Incoming Tide (Flood Tide)

The incoming  tide moves upstream away from the ocean.  It is usually slower because it moves against the flow of water from dams upstream.  Because of its slower speed, it us usually cleaner and less prone to stir up weeds than the outgoing tide.

Slack Tide

The slack tide is the time between the incoming and outgoing tides.  The current will stop flowing and go slack like the water in a lake or pond.

Neap Tides

Neap Tides occur the day before, during, and after the first and third quarter moons (a three day period).  Neap tides are small, or soft tides.  They usually produce a slow current, less water level change, less sediment and less weeds.

Spring Tides

Spring Tides occur the day before, during, and after the full and new moons (a three day period).  Spring tides are big, or hard tides.  They usually produce a strong current, high water level change, more sediment and more weeds.