Destination guide
Istanbul weather by month
June to August is the best time to visit Istanbul for warm, relatively dry weather, with July and August averaging 28°C by day. The catch is that midday outings can feel hot, and evenings offer limited cooling. For a gentler city break, May at 20°C and September at 24°C are better choices for spending much of the day outside. Winter suits travellers who do not mind cold evenings and working around rain.
- Hottest month
- 27.9°CAugust
- Coolest month
- 8.2°CJanuary
- Warmest sea
- 24.4°CAugust
- Flight from London
- 3 h 54 minShort-haul (up to 4.5 h) · estimated
Istanbul, month by month
A little perspective
Istanbul through the year
Every month at a glance; "best" marks our three top months on warmth, dryness and sunshine.
| Month | Day | Night | Sea | Sun/day | Rain mm | Rainy days | Days 25°C+ |
|---|---|---|---|---|---|---|---|
| January | 8.2°C | 4.1°C | 8.4°C | 3.1 | 85 | 12 | 0% |
| February | 8.8°C | 4.1°C | 7.3°C | 3.7 | 71 | 11 | 0% |
| March | 11.0°C | 5.6°C | 7.8°C | 4.8 | 72 | 11 | 0% |
| April | 15.1°C | 8.8°C | 10.2°C | 6.2 | 47 | 8 | 0% |
| May | 20.0°C | 13.6°C | 15.4°C | 7.8 | 36 | 6 | 6% |
| Junebest | 24.9°C | 18.4°C | 20.8°C | 10.4 | 35 | 6 | 50% |
| Julybest | 27.6°C | 21.1°C | 23.5°C | 11.8 | 19 | 4 | 88% |
| Augustbest | 27.9°C | 21.8°C | 24.4°C | 10.8 | 20 | 3 | 91% |
| September | 24.1°C | 18.5°C | 22.5°C | 8.2 | 45 | 6 | 42% |
| October | 19.2°C | 14.5°C | 18.9°C | 5.3 | 78 | 9 | 4% |
| November | 14.4°C | 10.0°C | 14.8°C | 3.9 | 72 | 10 | 0% |
| December | 10.2°C | 6.3°C | 11.1°C | 3.0 | 97 | 13 | 0% |
Day = average daytime high, night = average night-time low, 1991-2020.Sun is hours per day; rainy days count 1 mm or more.
Day, night and sea
Monthly average temperatures, 1991-2020
- Day
- Night
- Sea
Best months here
On warmth, low rainfall and sunshine, start with these.
When to go to Istanbul
For beach weather, look at months where the daytime average clears 25°C and rainy days stay low: July, August. December is the wettest month (97 mm, about 13 rainy days) and July the driest (19 mm). The sea is warmest in August at 24.4°C and coolest in February at 7.3°C.
Getting there
A direct flight from London Gatwick to Istanbul Sabiha Gökçen International Airport (SAW, 33 km from Istanbul) takes roughly 3 h 54 min - short-haul (up to 4.5 h) by UK standards. Time-zone: Europe/Istanbul.
Records and extremes, 1991-2020
The hottest day recorded in Istanbul between 1991 and 2020 reached 35.3°C on 13 July 2000; the coldest fell to -7.8°C on 27 January 2000. In August one day in ten tops 30.7°C and about 19% of days pass 30°C; in January one night in ten drops to -0.1°C or below. The wettest single month of the period was October 2010 with 252 mm, against a October average of 78 mm.
Sunrise, sunset and daylight in Istanbul
Local time on the 15th of each month; daylight-saving rules as of 2020.
| Month (15th) | Sunrise | Sunset | Daylight | Sunshine/day |
|---|---|---|---|---|
| January | 08:27 | 17:59 | 9.5 h | 3.1 h |
| February | 08:00 | 18:37 | 10.6 h | 3.7 h |
| March | 07:16 | 19:10 | 11.9 h | 4.8 h |
| April | 06:25 | 19:44 | 13.3 h | 6.2 h |
| May | 05:46 | 20:15 | 14.5 h | 7.8 h |
| June | 05:31 | 20:38 | 15.1 h | 10.4 h |
| July | 05:45 | 20:35 | 14.8 h | 11.8 h |
| August | 06:14 | 20:03 | 13.8 h | 10.8 h |
| September | 06:45 | 19:14 | 12.5 h | 8.2 h |
| October | 07:16 | 18:24 | 11.1 h | 5.3 h |
| November | 07:52 | 17:46 | 9.9 h | 3.9 h |
| December | 08:22 | 17:37 | 9.2 h | 3.0 h |
Winter into spring: pack layers and keep plans flexible
December to February is the least comfortable stretch for spending long periods outdoors. December averages 13 rain days, so a waterproof coat and plans you can rearrange are useful. January days reach 8°C, while nights average 4°C in both January and February; pack for cold evenings rather than relying on a light jacket. March brings a modest improvement to 11°C by day, but it is still cool and averages 10 rain days. April is more practical for outdoor exploring at 15°C, provided you keep a layer handy for evenings. May is the stronger choice for mild weather: days average 20°C, nights 14°C and rain falls on 6 days. It suits travellers who want comfortable walking weather without summer heat.
Summer: the strongest choice for warmth and sunshine
June starts summer with daytime averages of 25°C and nights of 18°C, making it a good compromise if you want warmth without the hottest evenings. July and August both average 28°C by day, so put longer walks earlier or later and leave room for a midday break. Nights stay warm at 21°C in July and 22°C in August; light clothing is more useful than heavy layers. July offers 12 hours of sunshine a day on average, while August has just 3 rain days. Neither month guarantees dry weather, but both suit travellers who prioritise sunshine. Sea temperatures reach 24°C, making summer the clearest choice if swimming matters.
Autumn: September stays warm, then rain becomes more likely
September is a good alternative to peak summer heat, with days averaging 24°C and nights 18°C. The sea remains at 22°C, so swimming is still a reasonable part of a trip, though 6 rain days mean you should allow some flexibility. October shifts towards jacket weather: daytime averages fall to 19°C, evenings to 14°C, and rain days rise to 9. It still suits outdoor plans if you are happy to carry a waterproof and adjust your timing. By November, days average 14°C and sunshine falls to 4 hours daily. Choose it for a trip that can comfortably mix time outside with shelter, rather than one dependent on warmth.
A little more detail
Istanbul weather FAQs
Plain answers, grounded in the averages.
What is the best time to visit Istanbul?
Judged on warmth, low rainfall and sunshine, the best months in Istanbul are August, July and June. August is the hottest month (average high 27.9°C) and January the coolest (8.2°C).
How many months a year is Istanbul over 25°C?
2 months in Istanbul average a daytime high of 25°C or more, and 5 average 20°C or more.
When is the rainy season in Istanbul?
December is the wettest month in Istanbul (97 mm on average) and July the driest (19 mm). Annual rainfall averages 677 mm.
What is the hottest temperature recorded in Istanbul?
The hottest day recorded in Istanbul between 1991 and 2020 reached 35.3°C on 13 July 2000; the coldest fell to -7.8°C on 27 January 2000. Records come from daily data for 1991-2020, not from a single station's all-time history.
When is Istanbul most comfortable for walking?
May and September offer a useful balance of warmth and manageable daytime temperatures, averaging 20°C and 24°C respectively. Both have 6 rain days on average, so take a light waterproof rather than assuming every day will stay dry.
When is the sea warmest in Istanbul?
July and August have the warmest average sea temperature at 24°C. September remains relatively warm at 22°C, while June averages 21°C. May's 15°C sea is much cooler, despite the increasingly pleasant weather on land.
Will I need a warm coat in winter?
A warm coat is a sensible choice. January and February nights average 4°C, and daytime temperatures reach only 8°C and 9°C respectively. Choose something waterproof or bring a separate rain layer, as rain is a regular winter consideration.
See also: Turkey weather by month · where else is hot in August
About these averages
ERA5-Land climate reanalysis via Open-Meteo (11 km grid) and NOAA Coral Reef Watch 5 km sea temperatures, 1991-2020
Averages computed from daily values at Istanbul. Sea temperature from the nearest 5 km sea cell, 2.5 km from that point. Sunshine hours are estimated from average cloud cover.Records are the highest and lowest daily values in that 30-year period, not all-time records. These are climate averages, not a forecast for your trip. How we measure holiday weather
- Hot · 25°C+
- Warm · 20°C to below 25°C
- Mild · 15°C to below 20°C
- Cool · below 15°C