Istanbul Weather
A month-by-month look at temperature, rainfall and what to pack in Istanbul. The annual average is 18°C high / 11°C low — hottest in July (28°C) and coldest in January (3°C).
Istanbul Weather at a Glance
As of 2026A quick summary of Istanbul's year-round climate and the best time to visit.
- Annual average
- 18° / 11°
- Best time to visit
- May, June, September
- Hottest month
- July (28°C)
- Coldest month
- January (3°C)
- Wettest month
- December (116mm)
- Driest month
- July (27mm)
As of 2026, Istanbul's weather averages 18°C high / 11°C low across the year, and the best time to visit for stable temperatures, rainfall and crowds is May, June, September. The hottest month is July (28°C), the coldest is January (3°C), and the wettest is December (116mm).
Best Time to Visit Istanbul
May is Istanbul's optimal month — 21°C days + 12°C nights + minimal rain. Bosphorus ferries + Princes' Islands at peak comfort. May 19 (Atatürk Memorial + Youth + Sports Day) is a national holiday — Turkish flags everywhere, public events at Taksim Square. Tourist sites stay open. Last month before tourist peak crowds. Hotel rates climbing weekly. Outdoor cafés + rooftop bars + Bosphorus walking all peak.
June marks summer arrival — 26°C days + 16°C nights + minimal rain. Hotel rates at yearly peak from mid-June (school holidays). Tourist crowds maximum. Bosphorus boat tours + Princes' Islands + outdoor cafés all at peak. Cappadocia hot air balloon at perfect weather. Indoor sights (Hagia Sophia, Topkapi) get crowded — early morning visits essential. Ramadan can fall in May/June (varies yearly) — check Islamic calendar. Restaurants close daytime; evening iftar buffets expand. Tourist sites stay open but cafés may close.
September is Istanbul's optimal post-summer month. 24°C days + 16°C nights + manageable rain. Hotel prices drop 20-30% from August peak. European school resumes mid-month — crowds drop significantly. Sea temperature still 21°C for last swimming. Outdoor sights + Bosphorus + Princes' Islands at perfect comfort. Istanbul Biennial (September-November, every 2 years) brings contemporary art to historic venues. Hagia Eirene + Müze Gazhane + Galata Greek School are biennial venues.
Istanbul Weather Month by Month
Tap any month for a detailed guide with what to wear, sunrise/sunset and air quality.
| Month | High/Low | Rain | Rainy days | Crowds | |
|---|---|---|---|---|---|
| January | 8° / 3° | 91mm | 13 | Quiet | Details → |
| February | 9° / 3° | 78mm | 12 | Quiet | Details → |
| March | 11° / 4° | 68mm | 11 | Moderate | Details → |
| April | 16° / 8° | 46mm | 9 | Busy | Details → |
| May | 21° / 12° | 36mm | 8 | Busy | Details → |
| June | 26° / 16° | 35mm | 6 | Very busy | Details → |
| July | 28° / 19° | 27mm | 4 | Very busy | Details → |
| August | 28° / 19° | 41mm | 5 | Very busy | Details → |
| September | 24° / 16° | 50mm | 6 | Busy | Details → |
| October | 19° / 12° | 80mm | 10 | Moderate | Details → |
| November | 14° / 9° | 96mm | 12 | Quiet | Details → |
| December | 10° / 5° | 116mm | 13 | Moderate | Details → |
What to Wear in Istanbul by Season
Light jacket + sweater + jeans. Pack umbrella but increasingly dry. Beautiful spring weather for outdoor sights.
T-shirts + shorts + swimwear. Light layer for evening sea breeze. Sunscreen mandatory.
Light coat + sweater + jeans. Pack a packable rain jacket — October rainfall increases.
Same as January — winter coat + sweater + jeans + scarf. Slightly less rain but still cold + windy.
Istanbul Weather FAQ
What is the best time to visit Istanbul? +
For weather, May, June, September are the most comfortable months. Highs sit around 21°C with relatively stable rainfall and crowds.
What are the hottest and coldest months in Istanbul? +
The hottest month is July with an average high of 28°C, and the coldest is January with an average low of 3°C. The annual average is 18°C high / 11°C low.
When does it rain most in Istanbul? +
The wettest month is December (116mm over about 13 rainy days) and the driest is July (27mm). Total annual rainfall is roughly 764mm.
What should I pack for Istanbul? +
Spring (Mar–May) averages 16/8°C — Light jacket + sweater + jeans. Pack umbrella but increasingly dry. Beautiful spring weather for outdoor sights. Summer (Jun–Aug) averages 27/18°C — T-shirts + shorts + swimwear. Light layer for evening sea breeze. Sunscreen mandatory. Autumn (Sep–Nov) averages 19/12°C — Light coat + sweater + jeans. Pack a packable rain jacket — October rainfall increases. Winter (Dec–Feb) averages 9/4°C — Same as January — winter coat + sweater + jeans + scarf. Slightly less rain but still cold + windy.
What is the weather in Istanbul this month (June)? +
June averages 26°C high / 16°C low with 35mm rainfall over about 6 rainy days. Crowds are very busy and prices are high.
Keep Planning Your Istanbul Trip
Why you can trust weather guide
Based in Chiang Mai for 8+ years, with 30+ countries visited across Southeast Asia, Japan, and Europe. Every detail in this guide is primary-source verified as of April 2026, with prices auto-refreshed via live exchange rate APIs. This isn't AI-generated boilerplate — it's written from the perspective of someone who has actually been there.