How long are tides slack

We also happened to time our trip so we were returning to Vancouver against the current, however we used the shallower water near the sides of the channel where the current is weaker to get under the bridge. Video: Sail against current. Another thing to consider is the interaction between wind and current. When the wind and current are travelling together, the seas are calmer than when they are opposing each other. The turn of the tide can cause a relatively flat but windy channel to build into rolling waves and whitecaps.

When fast-flowing tidal currents are forced to pass through narrow channels, they can create dangerous tidal rapids with standing waves, large back eddies and intimidating whirl pools. At first sight, a passage at peak flood with raging rapids might look impassable, when in fact, you just showed up at the wrong time.

These passages can be navigable in a sailboat, but only at slack current. If you miscalculate the slack and arrive too late, the current may have already become too strong and you may have to wait for hours before the next window of opportunity to pass. Here, the narrow opening between the Strait of Georgia and Sechelt Inlet sees flows of up to High slack zero current and high tide high sea-level elevation occur at the same time. They often appear to happen at different times in the tide and current tables because tide and current stations are not located in the same place.

Thus, the difference in time merely represents the time lag between one station and the other as the water moves between them. High slack refers to when the tide has come all the way up and pauses for a moment, causing current to drop to almost nothing, before reversing direction and going out as the tide drops.

In terms of 'which one is more important, high slack or high tide', that depends on the situation. If you're navigating through an area with high current, you will want to know when high or low slack is so that you're not travelling against the current as you travel through that area.

Alternatively, if you're looking to pass over a shoal or shallow water, you'll want to know when the tide is high and when it is low so you don't run the risk of hitting the bottom. In other words: "High slack is a period of zero current which happens at high tide before it ebbs". The inverse is that at low slack , the tide has gone all the way down and the current comes to a brief stop as it switches from ebbing to flooding. To learn how to read published tide and current tables, see Learning Goal 11e.

Eventually the current would stop slack but the tide would continue to rise from the ocean. After a while the river would run backward upstream. Well here is an example where the slack and high tide does not coincide. This is called a flood current. As the tide recedes, the waters move away from the shore.

This is called an ebb current. The movement of water toward and away from the shore is illustrated by the movement of the green seaweed. Basically, tides are very long-period waves that move through the oceans in response to the forces exerted by the moon and sun. The current will continue to increase in speed for half its period, then start to gradually slow as it approaches Low Water slack, where again it stops moving completelyfor a very brief time before reversing direction and the cycle starts over.

To determine the time of High and Low Water Slack - the Nor'east magazine use to publish the time each week for all the inlets and bays, this was the best and easiest way, but i don't think they do it any longer. Don't know why.

The Long Island Fisherman has a table that helps you calculate the times for certain general areas. Other than that, I don't know where you can find the exact times. Anyone out know?? Let me give you a example. In the Sandy Hook Pilots tide book, which is the tidal reference guide for shipping in the NY area, it clearly states that the 'North River is running flood 15 feet below the surface 1 hour before turing from ebb to flood at surface'.

Now i would say this is roughly a constant for the North River I mentioned earlier, that you can have a stated incoming tide for the ocean, yet, still have a outgoing tide at the stated incoming time! We have seen this some many times In you question, you are confusing tide with current This does not mean that the waters in a given area does not move Many areas do not give a slack water period, but you try to find the closest station to these points, and make slight adjustments.

I know this sounds confusing, but the only place to find this are tidal reference tables. Slack after high. Hi Logic, I'll give you my experiences for the times for slack after high. Under normal conditions in Stony Brook harbor I find slack after high to occur about 45 minutes after the posted high tide time.

In FI inlet I typically expect the high slack water to occur about 2 and a half hours after high tide. This is all variable depending on many conditions. I find wind to be the main factor though. Say you have wind with the incoming current in a particular inlet, the current may continue to flood much longer and the slack will last much longer as well, as the current has to fight against the wind to turn.

On the other hand, wind against an incoming current may cause slack to occur prematurely and it will be very brief. Like most have said, the key is to know the typical conditions for the area s you fish and then know how to apply the weather conditions to the area so you know what to expect when you get there. I'll see you out in FI this fall. I have been after Nerd for a few months to post the current charts see "current charts" in the Website forum but haven't received any update on how it's going.