Extremely cold northeasterly or easterly winds blowing in eastern Russia and central Siberia are called buran. Snowladen cold winds blowing out from the Russian Tundra are named as purga. On certain occasions, these local winds are very intense and violent.
With the onset these winds the coldest weather is experienced in the affected area. In France, extremely cold winds occurring in winter are called bise. In southern Spain they are known as levanter, which a strong easterly wind of the Mediterranean, particularly in the Strait of Gibralter.
It produces damp and foggy weather. Norther is another cold northerly wind which occurs in winter over the region from Texas southward across the Gulf of Mexico and the western Caribbean. These winds originate from the winter anticyclones prevailing over the southern United States.
Similarly, the northwesterly cold wind blowing from the pampas of South America is called pampero. Off the coast of Argentina it blows from July to September. Sometimes dust-storms accompany these strong winds which, under favourable conditions, may yield precipitation.
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During the colder part of the year a strong to violent northeast wind blows in the Gulf of Papagayo, on the northwest coast of Costa Rica and in the adjoining Pacific coastal water. This local wind is called papagayo, after the name of the gulf.
Tehuantepecer is still another local name given to a strong northerly wind blowing in southern Mexico and northern Central America. Friagem of the Amazon Valley and the hahoob of Sudan are similar cold winds of local origin. The onset of these local winds lowers the temperature considerably. Such winds may persist for 3 to 5 days.
Besides the above-mentioned local winds, there are a few more such as, cat’s paw; cordo- nazo, gregale, chubasco, etc. which blow in various parts of the world under different local conditions. Some of the local winds may be warm, while others may be cold and dry. Some are associated with warm air-mass, while the others may be of cold air-mass type.
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It may be pointed out that these local winds are invariably associated either with a cyclone or an anticyclone. Whatever be the case, they have a great impact on the weather and climate of the locality they visit.
All the cold winds, which originate when a large mass of cold air accumulated over a highland area descends into the valleys and lowlands, are designated as gravity winds or katabatic winds or fall winds or drainage winds.
In different locations they are given different names such as mistral, bora, willywaw, etc. All of these winds are, in fact, down-slope winds.
The local winds that are extremely hot or cold affect the environment in various ways. They exert a great stress on animals as well as vegetation. They also transport atmospheric pollutants from one region to another.
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But there are certain categories of local winds like the see breeze and the land breeze that are most welcome features of the environment for the people living in the coastal regions.