tIDES EXPLAINED:
January 15, 2025
By NBOA
High tide
This is when the water level is at its highest. It’s a great time for boating because there’s more water to navigate in, making it easier to avoid obstacles near the shore.
Low tide
The opposite of high tide, this is when the water level is at its lowest. Boaters need to be extra careful during low tide because rocks and other obstacles can be closer to the surface, making navigation trickier.
Slack tide
The short period when the water has little to no movement and happens right between the high tide turning to low tide and vice versa. As the water takes a little break before changing directions, it can appear glass-like.
Bore tide
Occurring in certain coastal rivers and bays, a bore tide is a strong tide that pushes a wave or a series of waves up a body of water or against the current or natural flow of water.
SEMI-DIURNAL tide
In a semi-diurnal tide, two high tides and two low tides, with roughly equal heights, occur each day. This happens in the Atlantic Ocean, as the sea rises and falls twice daily.
DIURNAL tide
In diurnal tides, you see only one high tide and one low tide each day. For example, in the Gulf of Mexico, the water will rise and fall just once a day.
MIXED tide
A combination of semi-diurnal and diurnal tides, a mixed tide has two high tides and two low tides each day, like semi-diurnal, but the heights differ. One high tide might be really high, and the other not so much.
Brown tide
This is caused by a bloom, or overgrowth, of marine algae in the water, which turns the water a darker brownish color.
Red tide
Red tide is a more commonly known phenomenon caused by a bloom of toxic algae. These algae can produce toxins that are harmful to marine life, birds, and humans.