Košava ( sr-cyr, Кошава, ) is a cold, very

squall A squall is a sudden, sharp increase in wind speed lasting minutes, as opposed to a wind gust, which lasts for only seconds. They are usually associated with active weather, such as rain showers, thunderstorms, or heavy snow. Squalls refer to the ...

y southeastern

wind Wind is the natural movement of atmosphere of Earth, air or other gases relative to a planetary surface, planet's surface. Winds occur on a range of scales, from thunderstorm flows lasting tens of minutes, to local breezes generated by heatin ...

found in parts of Eastern Europe and the Balkans. It starts in the

Carpathian Mountains The Carpathian Mountains or Carpathians () are a range of mountains forming an arc across Central Europe and Southeast Europe. Roughly long, it is the third-longest European mountain range after the Ural Mountains, Urals at and the Scandinav ...

and follows the

Danube The Danube ( ; see also #Names and etymology, other names) is the List of rivers of Europe#Longest rivers, second-longest river in Europe, after the Volga in Russia. It flows through Central and Southeastern Europe, from the Black Forest sou ...

northwest through the Iron Gate region where it gains a jet effect, then continues to

Belgrade Belgrade is the Capital city, capital and List of cities in Serbia, largest city of Serbia. It is located at the confluence of the Sava and Danube rivers and at the crossroads of the Pannonian Basin, Pannonian Plain and the Balkan Peninsula. T ...

. It can spread as far north as

Hungary Hungary is a landlocked country in Central Europe. Spanning much of the Pannonian Basin, Carpathian Basin, it is bordered by Slovakia to the north, Ukraine to the northeast, Romania to the east and southeast, Serbia to the south, Croatia and ...

and as far south as

Niš Niš (; sr-Cyrl, Ниш, ; names of European cities in different languages (M–P)#N, names in other languages), less often spelled in English as Nish, is the list of cities in Serbia, third largest city in Serbia and the administrative cente ...

and Sofia. In the winter, it can cause temperatures to drop to around . In the summer, it is cool and dusty. It varies diurnally, and is strongest between 5:00 and 10:00 in the morning. Košava is usually caused by a low

pressure Pressure (symbol: ''p'' or ''P'') is the force applied perpendicular to the surface of an object per unit area over which that force is distributed. Gauge pressure (also spelled ''gage'' pressure)The preferred spelling varies by country and eve ...

zone over the

Adriatic Sea The Adriatic Sea () is a body of water separating the Italian Peninsula from the Balkans, Balkan Peninsula. The Adriatic is the northernmost arm of the Mediterranean Sea, extending from the Strait of Otranto (where it connects to the Ionian Se ...

and a corresponding high pressure zone in southern

Russia Russia, or the Russian Federation, is a country spanning Eastern Europe and North Asia. It is the list of countries and dependencies by area, largest country in the world, and extends across Time in Russia, eleven time zones, sharing Borders ...

. The name is also used traditionally in northwestern

Bulgaria Bulgaria, officially the Republic of Bulgaria, is a country in Southeast Europe. It is situated on the eastern portion of the Balkans directly south of the Danube river and west of the Black Sea. Bulgaria is bordered by Greece and Turkey t ...

to mean a northeastern or eastern wind. There is a saying that goes: "When košava blows, the

Nišava The Nišava or Nishava ( Bulgarian and sr-Cyrl, Нишава, ) is a river in Bulgaria and Serbia, a right tributary, and with a length of also the longest one, of the South Morava. Course Bulgaria The Nišava originates in western Bul ...

freezes". The speed and occurrence of the Košava wind declined from 1949 to 2010. The same study showed that Košava usually lasts for two or three days, one-day events being very rare. Košava wind blows when there is a high air pressure (an anticyclone) over Eastern Europe and/or west Asia and a low pressure (a cyclone) over the middle and/or western Mediterranean region. The strong anticyclone, however, is the main trigger for the Košava wind. Košava is also a gap flow windstorm. Košava's occurrence can be successfully forecast using the across-mountain

mean sea level pressure Atmospheric pressure, also known as air pressure or barometric pressure (after the barometer), is the pressure within the atmosphere of Earth. The standard atmosphere (symbol: atm) is a unit of pressure defined as , which is equivalent to 1,013.2 ...

and potential temperature differences.

References

Winds Climate of Serbia Climate of Bulgaria {{Serbia-stub

See also

References