The climate in Turkey has a vast diversity depending on the diverse topography and latitude.
Aegean and Mediterranean coastal areas >enjoy the typical Mediterranean climate. There is hardly a drop of rain during the sunny and hot summer (May to October). Winters are mild and rainy in these regions, and it very rarely snows at coastal areas, with the exception of mountainous areas higher than 2000 metres of these regions, which are very snowy and are frequently not passable. The water temperature in the Aegean and Mediterranean Seas is warm during the long summer season (May to October) which constitutes the swimming season and fluctuates between 23° and 28°C from north to south.
The region around the Sea of Marmara, including Istanbul, has a transitional climate between an oceanic climate and a semi-Mediterranean climate, but it does rain, albeit not a lot, during the very warm summer (as showers which tend to last for 15-30 minutes). Its winters are colder than those of the western and southern coasts. Snow is common at coastal areas, although it doesn't stay on the ground for long and is limited to only a few days every winter. The water temperature in the Sea of Marmara is also colder than the Aegean and Mediterranean Seas, with the water temperature reaching only between 20° and 24°C during the summer (June, July and August) and the swimming season is restricted to those summer months.
The Black Sea region has an oceanic climate (thanks to the protective shield effect of Caucasus mountains) with the greatest amount of precipitation and is the only region of Turkey that receives high precipitation throughout the year. The eastern part of that coast averages 2,500 millimeters annually which is the highest precipitation in the country. Summers are warm and humid while the winters are cool and damp. Snow is common at coastal areas, although it doesn't stay on the ground for long and is limited to only a few days every winter, though mountains are very snowy as it is expected to be and are frequently not passable, there are glaciers around the year in the highest zones. The water temperature in the whole Turkish Black Sea coast is always cool and fluctuates between 10° and 20°C throughout the year, and is even less suitable for swimming during the summer than in the Sea of Marmara.
Most of the coastal areas have a high level of relative humidity during most of the year which makes hot weather feel hotter and cold weather feel colder than it actually is.
Interior areas like Ankara, generally have hot summers (though the nights are cool enough to make someone who is wearing only a thin t-shirt uncomfortable outdoors) and cold and snowy winters. The more easterly the location is, the colder the winters are and the heavier the snow is. The northeastern part is the only inland area which has cool and rainy summers.
The southeastern region near the Syrian border has a desert-like climate, temperature is frequently above 40°C during summers with no rain. Snowfall is occasional in winter.