Istanbul is pretty much a year-round destination. Always vibrant, always busy and always intriguing. When you go though will determine what you choose to see or also the clothes to pack.
January and February
Expect cold weather and grey skies, with snow, sleet, and fog. The daily maximum is 8.8°C (47.8°F), and the minimum is 3.6°C (38.5°F). You could get lucky and instead get cold but crisp, clear days. In any case, there are plenty of amazing culture to explore indoors and spending time in meyhanes (taverns) can be cozy and romantic.
March and April
It’s always nice to get away in spring and March and April hover around of 12°C (54°F) but can be higher. There can be showers and can feel quite chilly at night so take a variety of clothes and go for layering. At the end of March or early April, you will get to see a host of blooming tulips as this is when the official International Tulip Festival runs.
It’s worth noting though the dates of the two biggest Muslim holidays, Ramadan (Eid Al Fitr) and Kurban Bayramı (Eid Al Adha) which land generally in March and April but dates do vary. During these holidays, there’s plenty of domestic and international travel and of course, this will affect hotel and travel costs. There may be some closures too at this time.
May to June
Temperatures are mild and exploring the city is comfortable. Restaurants spread out offering pleasant al fresco dining experiences especially in the markets or on roof tops.
July to August
Summer is peak season and lasts from June to August. Temperatures can be sweltering 27°C / 80.6°F high and 20°C / 68°F low and as days are longer you get to enjoy up to twelve hours of sunshine every day.
Crowds swell and queues may be at their longest for the most popular sights. The cafes and roof-top eateries along the Bosphorus are the places to be but they will be busy.
Some fun festivals are going on during these months.
- Chill-Out Festival in late May/June
- Istanbul Music Festival in June
- Istanbul International Jazz Festival every July.
September to October
Moderate temperatures
November and December
They say this is the low season, but you would never know it for the crowds. You could be lucky and the weather may be warm. There is also a chance of snow. At times you can see the fog brooding over the Bosphorous sometimes affecting the flow of the ferries.
The positive side of travel at this time is cheaper accommodation and you could spend more time indoors in Istanbul’s museums, mosques, and other sights without the crowds. It is best to avoid New Year as prices skyrocket.
Source : https://www.thetravelmagazine.net/best-time-to-visit-istanbul-turkey/
