Izmir is located in the Mediterranean climate zone with hot and dry summers and mild and rainy winters. The fact that the mountains extend perpendicular to the sea and the plains are inserted to the threshold of Central West Anatolia allows the maritime effects to spread inland. However, differences in physical geography such as elevation, aspect and distance from the coast lead to significant climate differences in terms of precipitation, temperature and insolation.

The average annual temperature varies between 14-18 ºC in the coastal areas. The hottest months are July (27.3 ºC) and August (27.6 ºC), while the coldest months are January (8.6 ºC) and February (9.6 ºC). In summer, the temperature in the coastal area is 1-2 ºC lower than in the interior with the effect of the sea breeze (Imbat). In the winter season, the average temperature of 7 ºC decreases from time to time due to the marine air mass penetrating from the north and northwest.

There are significant differences in the distribution of precipitation by months and seasons in Izmir. The average annual precipitation in Izmir is 700 mm. and more than 50% of the annual precipitation falls in winter, 40-45% in spring and fall, and 2-4% in summer.The number of days with snowfall is almost non-existent in low-lying areas. Both the number of days with snowfall and the duration of snow on the ground increase in higher areas. Surrounded by mountains and built around a gulf, Izmir has a high humidity in the air, reaching 49% in August when the highest temperature is recorded.

The wind, which is unstable and warm in the winter months, shows stability in the summer months. The prevailing wind direction in Izmir is southeast and west. The annual average sea water temperature is 18.5 ºC, with the lowest months being (11 ºC) and February (10.7 ºC) and the highest months being July and August (26.2 ºC).