[′grād·ē·ənt ‚wind]
(meteorology)
A wind for which Coriolis acceleration and the centripetal acceleration exactly balance the horizontal pressure force.

a horizontal, uniform motion of air in the absence of frictional force in a linear (geostrophic wind) or circular path that coincides with the isobars. The gradient wind blows when there is a balance between the active force of pressure gradient and inertial forces: centrifugal force and deflective force owing to the earth’s rotation—the Coriolis force. The gradient wind is the best approximation of the actual state of wind in a free atmosphere above the layer of friction (approximately 1,000 m above the earth’s surface).

Gradient wind and balance of forces in a depression in the Northern Hemisphere.
Any horizontal wind velocity tangent to the contour line of a constant pressure surface or an isobar. This movement of air is to the result of a combination of three forces: pressure gradient force, geostrophic force, and cyclostrophic force. In the Northern Hemisphere, the difference between the pressure gradient directed inward toward low pressure and the Coriolis force directed outward results in the centripetal force in a low-pressure area. Similarly, in anticyclonic motion, the difference between the Coriolis force and the pressure gradient results in the centripetal force.
References in periodicals archive ?
Due to the random, intermittent, and volatile nature of wind speed, in order to accurately describe the wind speed characteristics, in this paper, the wind speed's mathematical model was created using a combination of four components that are basic wind, gust wind, gradient wind and noise wind.
Gradient wind describes a wind field's steady energy that is changing slowly over time; it can be expressed as a superposition of a gradient component and the basic wind speed
Notice that in fine vortical structures, where the centrifugal force becomes important, the gradient wind balance (between pressure gradient, Coriolis and centrifugal forces) could advantageously replace the geostrophic balance for constraining slow modes.
One of the tough things to work out at this part is the transition between the sea breezes and the gradient wind.
Examples of specific topics covered include aircraft electrification, airmass, anabatic wind, boundary layer, convection, Dansgaard-Oeschger event, Dobson spectrophotometer, gradient wind, katabatic wind, meteorology, noble gases, pollution control, temperature scales, waterspout, and Venturi effect.
As long as the gradient wind does not exceed 23 knots, we would normally expect the morning NW wind to decrease and a SE sea breeze to develop over the Derwent around noon, local summer time.
In S to SE gradient wind situations, winds over Storm Bay and the Derwent are generally more uniform, although some acceleration can be expected near the more prominent points and headlands.
ii) Under any kind of offshore gradient wind flow, Storm Bay is affected by the significant topographic features of southern Tasmania and can be most frustrating.
With west gradient winds, the entire coast generally suffers from the effects of the lee trough.

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