Measured, not vibes
Best Time to Visit Istanbul
By measured weather comfort, the top months for Istanbul are October, September, June — and RouteVerdict's editorial pick, which also weighs crowds and prices, is April, May, June, September, October. The table below is computed from ERA5 reanalysis data for 2020–2024, measured at Istanbul (39 m elevation).
Month by month
Istanbul weather and comfort, 2020–2024
| Month | Avg high | Wet days | Comfort | Season |
|---|---|---|---|---|
| January | 10°C / 50°F | 10.2 | 28 | |
| February | 10.7°C / 51°F | 7.7 | 33 | |
| March | 11.5°C / 53°F | 10.3 | 35 | |
| April | 16.3°C / 61°F | 8.8 | 63 | |
| May | 20.8°C / 69°F | 8.5 | 81 | |
| June | 25.9°C / 79°F | 6.3 | 83 | Best |
| July | 29.7°C / 85°F | 2.7 | 72 | Shoulder |
| August | 30°C / 86°F | 2.5 | 70 | Shoulder |
| September | 26°C / 79°F | 5.8 | 84 | Best |
| October | 20.9°C / 70°F | 5 | 88 | Best |
| November | 16.2°C / 61°F | 7.3 | 64 | |
| December | 12.6°C / 55°F | 9.5 | 42 |
Comfort is RouteVerdict's 0–100 score: 100·exp(−(high−23)²/162) × (1 − min(0.35, wet days × 0.02)). The full method is on the methodology page. Weather data by Open-Meteo.com (ERA5, CC BY 4.0), 2020–2024 normals. Wet day = ≥1 mm precipitation.
What the seasons are actually like
Traveling to Istanbul month by month
Istanbul's comfort score peaks in autumn: October leads at 87.6 with an average high of 20.9°C, just ahead of September's 83.6 and June's 83. July and August are the hottest months, averaging 29.7°C and 30°C, but they're also the driest, at just 2.7 and 2.5 wet days — and RouteVerdict lists both as shoulder months rather than editorial picks, since comfort dips to 71.7 and 70.2 in the heat. Winter (December–February) drops to highs of 10–12.6°C and comfort scores of 28–41.5; March, at 10.3 wet days, is the wettest month of the year, narrowly ahead of January's 10.2.
FAQ
Istanbul timing questions
What is the best month to visit Istanbul?
By measured weather comfort (ERA5 2020–2024), the top months are October, September, and June, with October scoring highest. RouteVerdict's editorial pick is April, May, June, September, and October, which also weighs crowds, prices, and events.
What is the hottest month in Istanbul?
August, with an average daily high of 30°C (86°F).
What is the rainiest month in Istanbul?
March, averaging 10.3 days with at least 1 mm of precipitation.
When is shoulder season in Istanbul?
July and August — the best-scoring months outside both the measured top three and RouteVerdict's editorial peak-season pick.
Why don't July and August score higher for Istanbul despite being warm and dry?
July and August are Istanbul's driest months, at 2.7 and 2.5 wet days, but the heat — averaging 29.7°C and 30°C — brings comfort down to 71.7 and 70.2, below the autumn peak.
What is Istanbul's single best month for weather?
October, with an average high of 20.9°C, only 5 wet days, and a comfort score of 87.6 — the highest measured for any month.