Cape Verde hurricane — A tropical cyclone that develops off the Cape Verde (pronounced vurd) Islands just off the West Coast of Africa and becomes a hurricane before reaching the Caribbean Sea. The Cape Verde season peaks in August and September. A typical year would have between one and five, with an average of two.
Cone of uncertainty — Sometimes called the "cone of error," this shows the historical error at certain time periods in a tropical cyclone forecast. It is important to realize that sometimes the actual forecast scenario might be more or less accurate than the historical error cone.
Cyclone — A counter-clockwise rotating area of air that usually denotes unsettled weather, such as a hurricane.
Extratropical cyclone — A storm that forms outside the tropics, sometimes as a tropical storm or hurricane changes.
Eye — The low-pressure center of a tropical cyclone. Winds can be nearly calm, and sometimes the sky clears.
Eye wall — The ring of thunderstorms surrounding a storm's eye. The heaviest rain, strongest winds and worst turbulence are normally in the eye wall.
Hurricane — A tropical cyclone in which the maximum sustained surface wind speed exceeds 74 mph.
Hurricane hunters — Planes that fly into hurricanes to take measurements. In the Atlantic Hurricane Basin, hurricane reconnaissance is carried out by the U.S. Air Force Reserve's 53rd Weather Reconnaissance Squadron and NOAA's Aircraft Operations Center. The Air Force uses WC-130 planes based at Keesler Air Force Base in Mississippi, and NOAA uses P-3 planes based at MacDill Air Force Base in Tampa.
Hurricane season — Six months of the year with a relatively high incidence of hurricanes. The hurricane season in the Atlantic, Caribbean and Gulf of Mexico runs June 1 through Nov. 30. The hurricane season in the Eastern Pacific basin is May 15 to Nov. 30. The hurricane season in the Central Pacific basin is June 1 to Nov. 30.
Saharan air layer — A large area of dust emerging off the African continent into the Atlantic Ocean during the spring and summer. It usually extends 5,000 to 25,000 feet into the atmosphere and is associated with large amounts of dust, dry air and strong wind aloft. It generally weakens hurricane intensity by wrapping dry air into a storm, which tears it apart.
Spaghetti models — Describes the graphical output of several computer model forecasts for a tropical system placed on one graphic. The solutions often resemble a bowl of spaghetti.
Storm surge — An abnormal rise in sea level accompanying a hurricane or other intense storm. The height is the difference between the observed level of the sea surface and the level that would have occurred without a cyclone.
Storm tide — The actual level of sea water resulting from the astronomic tide combined with the storm surge.
Tropical cyclone — The generic term given all tropical depressions, tropical storms and hurricanes. A tropical cyclone has a warm core and must have a warm ocean and humid environment to survive. Also, a tropical cyclone will have its most intense winds concentrated close to the center.
Tropical depression — A closed low-pressure area with organized convection, heavy rain, and winds up to 38 mph.
Tropical disturbance — A distinct tropical weather system of apparently organized convection originating in the tropics or subtropics and maintaining its identity for 24 hours or more.
Tropical storm — A tropical cyclone with maximum sustained surface winds of 39 mph to 73 mph.
Tropical wave — An area of converging air and relatively low air pressure embedded within the deep easterlies. May lead to tropical cyclones.
Upwelling — The "bringing up of water" from deeper water toward the surface. A hurricane can "upwell" colder water to the surface as it moves along, which can weaken a hurricane if it becomes stationary.
Josh Linker, Bay News 9 meteorologist