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Definition:
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- Winds that, over a small area, differ from those that would be appropriate to the general large-scale pressure distribution, or that possess some other peculiarity. Often these winds have names unique to the area where they occur. Local winds may be classified into three main groups. The first includes diurnally varying airflows that are driven by local gradients of surface heat flux (e.g., near the shore of a sea or lake) or by diurnal heating or cooling of the ground surface in areas of sloping or mountainous terrain. These include land and sea breezes, mountain?valley circulations, and drainage and slope winds. The second group consists of winds produced by the interaction of a synoptic-scale flow with orography. These may be further subdivided into barrier jets, gap winds, downslope windstorms, and include such local phenomena as the tehuantepecer, Santa Ana, foehn, mistral, and bora. The third group includes those winds accompanying convective activity, more specifically individual thunderstorms or mesoscale convective systems. These are generally the surface manifestations of precipitation- cooled diverging outflow and in some locations are given special names due to the distinctive character of the weather associated with them (e.g., the haboob). 2. Local or colloquial names given to frequently occurring or particularly noteworthy winds (sometimes because of the bad weather associated with them), usually from a certain direction. Often these names reflect the direction from which the wind comes (e.g., sou'wester, nor'easter).
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