Surrounded by the majestic Alborz Mountains in the north and the central desert in the south, Tehran has a semi-arid climate with the characteristics of both Mediterranean and Continental climate. The weather in Tehran can be unpredictably harsh with extreme temperature fluctuations all of a sudden. The hottest month of the year is July and the coldest month is January.
Spring (March - April): The spring season in Tehran is the mild season of the year with the average low and high temperatures ranging from 4 to 20 degree Celsius.
Summer (May - August): Summers in Tehran are long, hot and dry with little to no rain. The temperatures can be scorching hot which makes it uneasy to explore the city's attractions during this time of the year.
Autumn (September - October): The temperature drops down a bit signifying the end of the summer. The average low and high temperature during this time is between 11 and 29 degree Celsius.
Winter (November - February): Winters in Tehran are cold and wet with the maximum occurrence of rainfall.
The peak and the best season to visit Tehran is during the spring when the climate is mild and enjoyable. Alternatively, if you want to escape the crowd and get great deals on your hotel bookings, then you can plan your visit during the autumn season.