Understanding tides is important if you will be boating in Key Largo, Florida Keys. Key Largo tides can make or break a fun day of boating. You really need understand how tides work, and how quickly they can change before setting off to boat around Key Largo, Fl. Keys.

Tides are the regular scheduled rises and falls in the sea level. These are accompanied by horizontal flows of water, that are caused by gravitational interactions between the Moon, Sun, and Earth. Tides occur all over the world’s oceans, but we notice them the most near coastline. Along the coastline we can see the high water mark on areas like sea walls. As the tide lowers we can see the growth of life that lives on the sea walls dealing with the daily exposure to a dry environment, and the a few hours later an underwater environment.

High and Low Tides

Most people usually think of the the Moon as orbiting the Earth, but in fact both the Earth and the Moon orbit around a common centre of mass – a point located inside the Earth. As the Earth and Moon move around this point, two forces are created at the Earth’s surface. Gravitational pull is created towards the Moon, and an inertial or centrifugal force directed away from the Moon. What this causes is two bulges in the Earth’s ocean, one towards the Moon and the other away from the Moon. Now as the Earth rotates on it’s axis, these bulges move over the Earth’s surface and this produces the high and low tides we experience.

This cycle will repeat every 24 hours and 50 minutes ( a lunar day ) not every 24 hours which is known as ( 1 solar day ).

Tidal Patterns

If it was only water moving around Earth, this would produce two equal daily rises and falls in sea level everywhere on Earth. This is known as semi-diurnal tide. Because landmasses interfere with the movement of the tidal bulges, and the Moon’s orbit tilts to the equatorial plane, we have different types of tides.

Many areas of the world experience tides differently. Some areas have just one high tide and one low tide each day. This is called diurnal tides. Many areas experience high and low of unequal size, and this is known as mixed semi-diurnal.

T unitedstates.htsgw.metric.12.cc23

Key Largo Tidal Pattern

In Key Largo’s local area, boaters need very closely follow the tide charts. Some man-made waterways nearly dry up at low tide. If you are traveling in a boat with a deep hull, this could mean becoming grounded, and having to wait many hours in the baking sun for the next high tide or having to call Tow Boat US or Sea Tow.




Additionally in Key Largo, we have some reef areas a few miles off-shore where at low tide the reef actually sticks out of the ocean, and this too can be an extremely dangerous boating hazard if you are not closely following tidal charts.


Dive boat DEEPER traveling through South Creek waterway at High Tide.

When nearshore around the mangrove trees it is very easy to see if the tide is high or low based on the amount of the roots exposed from the water level. Around the mangroves you will also be able to smell if it is low tide as the exposed root system emits a sulfur smell.

View of low tide on Mangrove trees in Key Largo

Monthly Cycle of Tides, Key Largo Tides

With the understanding of the daily tidal flow, there is also a monthly cycle that needs be taken into account. In this case, the Sun and Moon combine to drive the cycle.

Twice each month when we have New Moon and Full Moon, the Sun, Moon, and Earth are aligned causing the the two sets of tidal bulges to reinforce each other. This will cause an exceptionally high and low tides.

When boating in Key Largo, Florida Keys, it is also very important to take these times of the month into account, because this can actually make boating in many areas even harder.



Credits: American Museum of Natural History – Ocean by Fabien Cousteau





Tides for Key Largo, Tidal Patterns Worldwide
Tagged on: