of Eurasia and the Atlantic Ocean and Mediterranean Sea. With mean January temperatures around , and mean July temperatures of , it can be classified as a warm-humid continental or humid subtropical climate. In the north, the climate is more continental, with cold winters, and hot, humid summers along with well-distributed rainfall patterns. In the south, summers and autumns are drier, and winters are relatively cold, with heavy inland snowfall in the mountains. Differences in elevation, proximity to the Adriatic Sea and large river basins, as well as exposure to the winds account for climate variations. Southern Serbia is subject to Mediterranean influences. The Dinaric Alps and other mountain ranges contribute to the cooling of most of the warm air masses. Winters are quite harsh in the Pešter plateau, because of the mountains which encircle it. One of the climatic features of Serbia is Košava, a cold and very squally southeastern wind which starts in the Carpathian Mountains and follows the Danube northwest through the Iron Gate where it gains a jet effect and continues to Belgrade and can spread as far south as Niš. The average annual air temperature for the period 1961–1990 for the area with an altitude of up to is . The areas with an altitude of have an average annual temperature of around , and over of altitude around . The lowest recorded temperature in Serbia was on 13 January 1985, Karajukića Bunari in Pešter, and the highest was , on 24 July 2007, recorded in Smederevska Palanka. Serbia is one of few European countries with very high risk exposure to natural hazards (earthquakes, storms, floods, droughts). It is estimated that potential floods, particularly in areas of Central Serbia, threaten over 500 larger settlements and an area of 16,000 square kilometres. The most disastrous were the floods in May 2014, when 57 people died and a damage of over a 1.5 billion euro was inflicted. Hydrology Almost all of Serbia's rivers drain to the Black Sea, by way of the Danube river. The Danube, the second largest European river, passes through Serbia with 588 kilometres (21% of its overall length) and represents the major source of fresh water. It is joined by its biggest tributaries, the Great Morava (longest river entirely in Serbia with of length), Sava and Tisza rivers. One notable exception is the Pčinja which flows into the Aegean. Drina river forms the