Some Weather Terms That Boaters Need to Know
What is a Cyclone?
This is a meteorological phenomenon in which a large mass of air rotates around a centre of low atmospheric pressure and they are characterized by spiraling winds rotating about a zone of low pressure. The largest low-pressure systems are polar vortices and extra tropical cyclones. Tropical cyclones cause numerous thunderstorms, exceptionally destructive strong winds, and large volumes of rain.
A cyclone feeds on heat released when moist air rises causing condensation of the water content being lifted.
Are weather systems with high barometric pressure at their centre, around which air slowly circulates in a clockwise direction in the Northern Hemisphere or anticlockwise direction in the Southern Hemisphere. Anticyclones are associated with calm, fine safe boating weather.
What is an Anemometer?
An Anemometer is a device that will measure wind speed, important for boating on sea and inland on lakes.
This is a nautical term for the equatorial region of light winds between the trade winds and the Northern and Southern Hemispheres. The expression doldrums is used in sailing when a boat is becalmed, and more generally when a person is listless and at a loss – in the doldrums. Boaters can either row or await a breeze depending on the size of craft, larger boats would just sit it out and wait whereas dinghy and smaller boats may be paddled.
Located between 30 degrees North and South near to the equator, this area typically has calm or light and variable winds. Another name for the equatorial trough, the Intertropical Convergence Zone (ITCZ), or the doldrums.
As our American friends and the people of the Caribbean and Pacific Regions have experienced recently, this is the name for a tropical cyclone with sustained winds of 74 miles per hour (65 knots) or greater in the North Atlantic Ocean, Caribbean Sea, Gulf of Mexico, and in the Eastern North Pacific Ocean. This same tropical cyclone is known as a typhoon in the western Pacific and a cyclone in the Indian Ocean.
Knots are a nautical unit of speed equal to the velocity at which one nautical mile is travelled in one hour. Used primarily by boating and all sea-based activities and in weather observations. A knot is equivalent to 1.151 statute miles per hour or 1.852 kilometres per hour.
For new boaters and those who are not so new we will explain more nautical expressions each month.