Tornadic waterspouts are tornadoes that form over water or move from land to water. They have the same characteristics as a land tornado. They are associated with severe thunderstorms and are often accompanied by high winds and seas, large hail, and frequent dangerous lightning. They are a far more rare type of Waterspout than the Fair Weather Waterspout.
These types of funnels move from the surface of the water upward towards the sky. Cumulus clouds are the clouds you learned to draw at an early age and that serves as the symbol of all clouds much like the snowflake symbolizes winter.
Their tops are rounded, puffy, and a brilliant white when sunlit, while their bottoms are flat and relatively dark. Fair Weather Waterspouts usually form along the dark flat base of a line of developing cumulus clouds. This type of waterspout is generally not associated with thunderstorms. They can develop during sunny mild weather. While tornadic waterspouts develop upward in a thunderstorm, a fair-weather waterspout develops on the surface of the water and works its way upward.
By the time the funnel is visible, a fair-weather waterspout is near maturity and the event is nearly over. These types of Funnels can last minutes after they are formed. Fairweather waterspouts form in light wind conditions so they normally move very little and very slow.
They are far more common than the Tornadic Waterspouts. Another characteristic of fair weather waterspouts is that multiple vortices or funnels often form in the same area at one time.
Whenever a waterspout moves over land it is called a Landspout. However, Fair Weather waterspouts often unravel and dissipate as they approach land and rarely make it. Boaters should never come close to one to try and investigate. If a Waterspout does appear they are recommended to turn the boat in a degree angle and move away as fast as possible.
Sometimes in an event, the wind speed can be between 50 mph and up to mph. The size of a waterspout can be up to meters wide. If a boat gets inadvertently caught up in waterspout experts recommend that they:. If your out on the open water during the summer months, in light winds, look for some telltale signs in the line of flat bottom cumulus clouds or thunderstorms, or in lines of thunderstorms that can develop any time of year.
Although waterspouts are not as destructive as their land-based cousins their ability to carry anything in their path makes them dangerous to vessels and small craft. Not only can waterspouts cause havoc to mariners, but they can also devastate coral reefs and marine organisms that are close to the surface of the water. The Wilmington forecast office oversees five coastal counties, from Surf City in North Carolina to the South Santee River in South Carolina, and monitors marine weather up to 40 miles seaward.
Climate and Past Weather. About Waterspouts Waterspouts are similar to tornadoes over water. Waterspouts are generally broken into two categories: fair weather waterspouts and tornadic waterspouts. Tornadic waterspouts are simply tornadoes that form over water, or move from land to water. They have the same characteristics as a land tornado. They are associated with severe thunderstorms, and are often accompanied by high winds and seas, large hail, and frequent dangerous lightning.
The term fair weather comes from the fact that this type of waterspout forms during fair and relatively calm weather, often during the early to mid morning and sometimes during the late afternoon. Fair weather waterspouts usually form along dark flat bases of a line of developing cumulus clouds.
This type of waterspout is generally not associated with thunderstorms whereas tornadic waterspouts develop in severe thunderstorms.
Tornadic waterspouts develop downward in a thunderstorm while a fair weather waterspout begins to develop on the surface of the water and works its way upward. By the time the funnel is visible, a fair weather waterspout is near maturity.
Fair weather waterspouts form in light wind conditions so they normally move little. If a waterspout moves onshore, the National Weather Service issues a tornado warning as some of them can cause significant damages and injuries to people.
Typically, fair weather waterspouts dissipate rapidly when they make landfall, and rarely penetrate far inland. This rising air carries water vapour high into the sky where it creates rain showers, storms and cumulus clouds. As the air rises, it can tilt some of the horizontal spinning air near the surface into the vertical direction. When this vertical spin concentrates at a particular point it starts sucking up water — and you have yourself a waterspout.
Because waterspouts form on the line where two winds meet, you sometimes see a line of waterspouts in a row where the spinning low-level air is sucked upwards at a few different points. Most mornings, cooler nighttime air blowing off the land meets warmer air sitting out to sea. Usually this results in a line of clouds sitting offshore where the two air masses meet. Under the right conditions — most often in autumn and winter, when the land gets colder but the sea stays relatively warm — the collision becomes more dramatic and waterspouts appear.
This makes them very hard to forecast with any level of confidence.
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