Heidelberg has an oceanic climate (K�ppen climate classification Cfb), defined by the protected valley between the Pf�lzerwald and the Odenwald. Year-round, the mild temperatures are determined by maritime air masses coming from the west. In comparison to the nearby Upper Rhine Plain, Heidelberg's position in the valley leads to more frequent easterly winds than average. The hillsides of the Odenwald favour clouding and precipitation. The warmest month is July, the coldest is January. Temperatures rising to more than 30�C in midsummer are no rarity. According to the German Meteorological Service, Heidelberg was the warmest place in Germany in 2009
