The climate of Azerbaijan is unique. Nine of the Earth's eleven climactic zones can be discovered in Azerbaijan.In general, the best time to visit is mid April through October when days are warm or hot (highs in the 70s and 80s F/21-30 C). July and August in Baku can bring daytime highs of up to 100 F/38 C. Evenings tend to be cool, even in the summer (low temperatures can reach 65 F/18 C). Don't go from December to late February, when inland temperatures can be bitterly cold -- even in Baku, it can reach below the freezing point. The climate varies considerably from east to west -- in the western mountains, the weather is drier and more extreme. The eastern part of Azerbaijan, near the Caspian Sea, has a more moderate climate. No matter when you go, be sure to take a sweater for the cool evenings.