Description

Zonda wind is a regional term for the warm and dry föhn wind that often occurs on the eastern slope of the Andes, in Argentina.

Fohn winds are downsloping winds that become warm and very dry due to adiabatic compression because of the higher pressure at lower elevations. The compression also tends to accelerate the winds.

Separately, zonda is also used to describe a hot, humid north wind in the Pampas of South America.

1) A dry Föhn wind in the central Argentine

The Zonda is a dry wind (often carrying dust) that starts as polar maritime air, warmed by descent from the crest of the mountains, approximately 20,000 ft above sea level. The wind may exceed a velocity of 65 km/h (40 mph).

While this type of föhn wind may occur over most central parts of western Argentina, its effects are more impressive in La Rioja, San Juan, and northern Mendoza provinces, where the mountain barrier (the Andes) is higher, while to the north the Puna plateau dissipates these winds.