There are certain local winds which are cold and dust-laden or cold and raw. These local winds occur under different conditions. Some of the cold air-mass type winds are discussed below.
Mistral is a cold northwest wind that blows into the western Mediterranean basin from higher elevations to the north. These winds are of common occurrence during winter months. They are extremely cold and dry.
Mistral descends from the high Auvergne Plateau to the Rhone Valley on the southern coast of France. Such stormy, cold northerly winds are experienced from the mouth of Ebro to the Gulf of Genoa along the Mediterranean coast.
In the region of eastern shore of the Adriatic Sea, a cold, dry north-easterly wind blowing down from the mountains is called bora. These winds blow in very strong gusts with velocities ranging from 128 km to 196 km per hour.
Along the northeastern shore of the Adriatic Sea a narrow coastal plain is flanked by the Istrian Plateau where an anticyclone develops in winter as a result of which the air becomes very cold.
The accumulation of very cold and dense air under the pull of gravitation descends the slopes of the plateau as a cold and gusty wind. In the winter season, however, wind is strongly influenced by the general pressure distribution and cannot be ascribed to purely local causes.
These down-slope winds, no doubt, are warmed by their descent, but even then they are colder than those along the coastal lowlands. The bora sometimes rushes to the sea at a speed of 160 km per hour. This type of wind is often associated with the passage of an extra-tropical cyclone.
Bora-type winds bring unusual and prolonged subfreezing temperatures along the coastal lowlands during winter. The bora of the northern Adriatic is a typical example of ‘fall winds’.
Similar winds also occur on the northern Black Sea coast, in Japan, northern Scandinavia and Novaya Zemlya. These winds occur specially during the winter. At times, they may attain hurricane force at the foot of mountains and may cause tremendous property damage.
It is a violent and extremely cold wind laden with dry snow picked up from the ground. Blizzard represents a severe weather condition characterized by very low temperatures, strong winds, and a great amount of snow.
Originally this term was used for the snow storms Great Plains to the east of Rocky Mountains in the United States of America. These severe storms originate from the anticyclones in the rear part of a moving depression.
These cold winds hay subfreezing temperatures and carry abundant supply of ice-crystals and snow. But, now, the term is used for the winds laden with dry snow blowing in higher latitudes.
Such blizzards are common occurrence in the Antarctic. Wind velocity, on occasions, reaches 120 km to 160 km per hour and the temperature is as low as -7° Celsius.