Wind Speed - the ratio of the distance traveled by the air to the time taken to cover the distance
Wind Vane - an instrument used to indicate wind direction ...
wind speed - Ratio of the distance covered by the air to the time taken to cover it. The instantaneous speed corresponds to the case of an infinitely small time interval. The mean speed corresponds to the case of a finite time interval.
WIND SPEED
The rate of the motion of the air on a unit of time. It can be measured in a number of ways. In observing, it is measured in knots, or nautical miles per hour. The unit most often used in the United States is miles per hour.
Wind Speed The rate at which air is moving horizontally past a given point. It may be a 2-minute average speed (reported as wind speed) or an instantaneous speed (reported as a peak wind speed, wind gust, or squall).
WIND SPEED: The rate of wind movement in units of distance/time.
WIND VANE: An instrument used to indicate wind direction.
wind speed—Rate of wind movement in distance per unit time.
wind vane—An instrument to indicate wind direction.
wind velocity—A vector term to include both wind direction and wind speed.
Jet Wind Speed Profile
A vertical wind speed profile characterized by a relatively narrow current of high winds with slower moving air above and below. A large wind (speed) shear occurs above and below the jet axis.
Jetty ...
Jet Wind Speed Profile - permalink - collapse
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Peak Wind Speed The maximum instantaneous wind speed since the last observation that exceeded 25 knots.
Pendant Echo Radar signature generally similar to a hook echo, except that the "hook" shape is not as well defined.
GALE- A wind speed ranging from 39 to 54 mph.
GEM- Forecast model. Global Environmental Multiscale - developed by the Meteorological Service of Canada (MSC) ...
Wind speed is measured by an anemometer, of which there are many kinds. Most common was probably the 3-cup freely rotating anemometer that is calibrated in a wind tunnel.
Wind speed is given here in the units of "knots" (knt). A "Knot" is a nautical mile per hour.
1 Knot = 1.15 Miles Per Hour (MPH)
1 Knot = 1.9 Kilometers Per Hour (KM/HR) ...
Wind Speed Indicator.
"N O T E" All weather articles written by the author, weather records for Bath, Pa. USA, graphs, graphics, pictures, are copyrighted and are owned by the author.
Wind speeds in the range of 13 to 19 knots.
Monsoon
The term originally referred solely to the winds of the Arabian Sea which blow for about six months from the north-east (in winter) and for six months from the south-west (in summer), ...
Wind speed determined by averaging observed values over a two-minute period.
SVR
1. Severe ...
VA = wind speed
For example, if the temperature is 20° and the wind 20 mph:
Tw = 20 - 1.5 x 20 ...
GALE: Wind speeds from 39 to 54 mph (34 to 47 knots).
GOES: Geostationary Operational Environmental Satellite.
GUST: A brief, sudden increase in wind speed with a fluctuation greater than 10 knots during a period less than 30 seconds.
A local wind speed maximum within a jetstream.
Jetstream
Relatively strong winds concentrated in a narrow stream in the atmosphere, normally referring to horizontal, high-altitude winds.
GALE: Wind speeds from 39 to 54 mph (34 to 47 knots).
GEOSTATIONARY SATELLITE: A satellite that rotates at the same rate as the earth, remaining over the same spot above the equator.
To measure wind speed and realise that it can be done with minimal equipment and surprising accuracy.
Equipment
strong thread or thin fishing line - about 40 cm long
ping-pong ball ...
Category 4: wind speeds 131-155 m.p.h.
Category 5: wind speeds over 155 m.p.h.
Sandstorm - A strong wind which carries sand through the air. Usually occurs in desert regions, often among sand dunes.
where u is the wind speed (in meters per second) at height z (in meters), and ur is the known wind speed at a reference height zr. The exponent (α) is an empirically derived coefficient that varies dependent upon the stability of the atmosphere.
F numberMaximum wind speedDamage
F0 (weak)
65-115 km/h
Light - trees damged, possibly uprooted, street signs damaged ...
The variation in wind speed (speed shear) and/or direction (directional shear) over a short distance. Shear usually refers to vertical wind shear, i.e.
JETMAX - A local wind speed maximum in a jet stream. Vertical wind shear increases abruptly beneath the jet max. Also called JET CORE.
Wind Aloft- the wind speeds and wind directions at various levels in the atmosphere above the area of surface weather observations, usually above about two thousand feet AGL.
Typhoon
Maximum wind speed of 64 knots or more.
Unstable Air Mass
Air mass having static instability in its lower layers; convective clouds and precipitation occur if its moisture content is sufficiently high.
Sustained Wind: Wind speed determined by averaging observed values over a 2-minute period.
Gale warningSustained wind speeds from 34 to 47 knots (39 to 54 mph). Glazea layer or coating of ice that is generally smooth and clear, and forms on exposed objects by the freezing of liquid raindrops.
The scale categorizes potential damage based on barometric pressure wind speeds, and storm surge. See the scale. ST. ELMO'S FIRE A luminous, and often audible, electric discharge that is intermediate in nature.
GGusts- A rapid fluctuation of wind speed with variations of 10 knots or more between peaks and lulls.G/KGGrams per KilogramGageIn hydrologic terms,
1) A device for indicating the magnitude or position of a thing in specific units, ...
SPSSevere Weather Potential StatementSQLNSquall LineSquallA strong wind characterized by a sudden onset in which the wind speed increases at least 16 knots and is sustained at 22 knots or more for at least one minute. 2.
Peak gust In United States weather observing practice, the highest "instantaneous" wind speed recorded at a station during a specified period, usually the 24-hour observation day. Therefore, a peak gust need not be a true gust of wind.
Therefore, spotters should not estimate wind speeds or F-scale ratings based on visual appearance alone. However, it generally is safe to assume that most (if not all) wedges have the potential to produce strong (F2/F3) or violent (F4/F5) damage.
PDTPacific Daylight TimePeak DischargeIn hydrologic terms, the rate of discharge of a volume of water passing a given locationPeak GustThe highest instantaneous wind speed observed or recorded.
It is used to indicate wind speed and direction.air densityThe mass per unit volume of air; about 1.275 kilometer per cubic meter at 0° C and 1000 millibars.
Wind speeds are generally 80-150 knots (40-75 m/s), but can be much greater over eastern seaboards of large land masses, e.g. speeds of 400 kt (200 m/s) have been reported over east Asia/NW Pacific.
3.
winds up to 17 m s−1(34 knots); 2) tropical storm, with winds of 18-32 m s−1(35-64 knots); and 3) severe tropical cyclone, hurricane or typhoon, with winds of 33 m s−1(65 knots) or higher. It should be noted that the wind speeds ...
Its vortex, typically a few hundred meters in diameter, usually rotates cyclonically (on rare occasions anticyclonically rotating tornadoes have been observed) with wind speeds as low as 18 m s-1 (40 mph) to wind speeds as high as 135 m s-1 ...
Anemometer Instrument which measures wind speed or wind speed and direction.
In the western South Pacific and the Indian Ocean severe tropical cyclones (wind speeds of 74 mph or greater) are simply called cyclones. Australian, Indian, and east African weather services will use this term to describe such storms.
A stability index developed by the Air Force which incorporates instability, wind shear, and wind speeds as follows: SWEAT = (12 Td 850 ) + (20 [TT-49]) +( 2 f 850) + f 500 + (125 [s+0.2]) where Td 850 is the dew point temperature at 850 mb, ...
Hurricane - (also known as (Typhoon, Tropical Cyclones, Willy- Willies) Tropical storms with wind speeds of 64 knots (117km/h) up to 240 knots (414 km/h) that can be thousands of square kilometers in size.
Entrance Region - The region upstream from a wind speed maximum in a jet stream (jet max), in which air is approaching (entering) the region of maximum winds, and therefore is accelerating.
Exit Region - The region downstream from a wind speed maximum in a jet stream (jet max), in which air is moving away from the region of maximum winds, and therefore is decelerating.
Wind-Chill Factor: The accelerated heat loss from exposed skin due to increased wind speed. A non-physical value which combines the effect of air temperature and the wind speed to illustrate how the air "feels.
f 850 is the 850-mb wind speed (in knots),
f 500 is the 500-mb wind speed (in knots), and
s is the sine of the angle between the wind directions at 500 mb and 850 mb (thus representing the directional shear in this layer).
Fujita scale (also F scale ) - A scale of wind damage intensity in which wind speeds are inferred from an analysis of wind damage: F0 (weak): 40-72 mph, light damage. F1 (weak): 73-112 mph, moderate damage.
A type of instrument used for measuring wind speed by measuring the wind induced changes in the temperature of a metal wire that is heated by an electric current and cooled by convective heat loss.
BEAUFORT WIND SCALE A system of estimating and reporting wind speeds. It is based on the Beaufort Force or Number, which is composed of the wind speed, a descriptive term, and the visible effects upon land objects and/or sea surfaces.
A system used to classify wind speed, developed in 1805 by British Admiral Francis Beaufort. The scale was initially developed for ships at sea but has latterly been adapted for use on land.
anemometer: an instrument that measures wind speed.
anticyclone: a body of air that circulates clockwise and outward in the Northern Hemisphere and counterclockwise and outward in the Southern Hemisphere, ...
Anemometer- An instrument that measures wind speed.
Aneroid Barometer- An instrument built around a metal structure that bends with changing air pressure. These changes are recorded on a pointer that moves back and forth across a printed scale.
Anemometer- An instrument used to measure wind speed.
Aneroid barometer- An instrument that measures changes in air pressure without using a liquid. Changes in the shape of an airtight metal box cause a needle on the barometer dial to move.
Cup anemometer An instrument used to monitor wind speed. Wind rotates the cups, and that motion is calibrated in wind speed.
Cyclogenesis The birth and development of a cyclone; a low-pressure system.
High Wind Advisory- This product is issued when high wind speeds may pose a hazard.
High Wind Warning- Issued when sustained winds will be 40 mph or greater for at least one hour, or any gust of wind expected to be 58 mph or greater.
Wind shear: The change of wind speed and/or direction in the atmosphere along a given direction.
Windsocks: Used to estimate wind speed and direction at airports.
Anemometer - An instrument used to determine wind speed. Aneroid Barometer An instrument for measuring air pressure: it consists of evacuated metal chambers that are very sensitive to variations in air pressure.
Aerovane A wind instrument that indicates or records both wind speed and wind direction.
Air density See Density.
Air mass A large body of air that has similar horizontal temperature and moisture characteristics.
Wind shear - A changing of wind speed or direction with distance; vertical wind shear is changing of wind with respect to height.
Zonal - In the west-east direction.
 See also: Wind, Air, Weather, Surface, Temperature
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