Istanbul at a glance
- Best time
- May – Sep
- Warmest month
- Aug · 28°
- Warmest sea
- Aug · 24.4°
- Sunshine a year
- 2,590 h
- Rain a year
- 677 mm
- Climate
- Temperate
- Time zone
- UTC+3
- Elevation
- 39 m
Climate in Istanbul
Istanbul has a temperate climate with warm summers and cool winters. August is the warmest month with average highs of 28 °C, while January is the coolest at 9 °C. With around 2,590 hours of sunshine a year, Istanbul is sunny; July is the sunniest month with 11.0 hours a day.
Weather in October
Holiday weather in October
Good
Best time to visit: May – September
What is the weather like in Istanbul in October?
In October, Istanbul is mild: daytime highs average 19 °C, and nights cool down to about 15 °C. The sea averages 19.2 °C – bracing, so a wetsuit helps for longer swims. Expect around 6 hours of sunshine a day. Rain falls on about 9 days, adding up to 73 mm. All in all, October is a good month for a holiday in Istanbul.
More details for October
- Daylight
- 11 h 11 min07:14 – 18:25
- UV index
- 4 · moderateclear sky, noon (estimate)
- Muggy days
- 0 daysdew point 18 °C or more
- Wind
- 21 km/haverage daily peak
- Cloud cover
- 50 %on average
- Hot days
- 0 days30 °C or more
- Snow days
- 0 days1 cm or more of fresh snow
- Time zone
- UTC+3Europe/Istanbul
How the score comes together
- Temperatureweight 50 %100 %
- Sunshineweight 20 %45 %
- Few rainy daysweight 30 %66 %
Each factor is rated from 0 to 100 % and weighted for the travel style “City break”.
What to pack in October
- Wetsuit for longer swims
- Sunscreen
- A jumper for the evenings
- Rain jacket or umbrella
Sea temperature in Istanbul
Monthly sea surface temperature with the range of cooler and warmer years.
8 in 10 years: 18.1 – 20.6 °C
Swimming season: Jun – Sep
- cold
- fresh
- refreshing
- pleasant
- warm
- very warm
The sea temperature in Istanbul ranges from 8.4 °C in February to 24.4 °C in August. It is warm enough for a comfortable swim (20 °C and more) from June to September.
From October to January the sea is even warmer than the afternoon air. The sea temperature varies from year to year: in August, eight out of ten years were between 23.3 and 25.3 °C.
| Month | Average | Cool year | Warm year | Feels |
|---|---|---|---|---|
| JanuaryJan | 9.4° | 7.9° | 10.9° | cold |
| FebruaryFeb | 8.4° | 6.8° | 9.7° | cold |
| MarchMar | 9.0° | 8.0° | 10.4° | cold |
| AprilApr | 11.6° | 9.9° | 12.8° | cold |
| MayMay | 16.1° | 14.9° | 17.2° | cold |
| JuneJun | 21.0° | 19.8° | 21.9° | refreshing |
| JulyJul | 23.7° | 22.6° | 24.6° | pleasant |
| AugustAug | 24.4° | 23.3° | 25.3° | pleasant |
| SeptemberSep | 22.6° | 21.5° | 23.5° | refreshing |
| OctoberOct | 19.2° | 18.1° | 20.6° | fresh |
| NovemberNov | 15.5° | 14.1° | 16.9° | cold |
| DecemberDec | 12.0° | 10.8° | 13.4° | cold |
Sunshine hours in Istanbul
Average hours of bright sunshine per day, next to the length of the day. Tap a month to select it.
In October, the sun shines for about 5.7 of 11.2 hours of daylight in Istanbul, 51 % of the day.
Sunshine hours count the time with bright, direct sunshine (WMO definition, estimated from model data); daylight is the time from sunrise to sunset on the 15th of the month.
Rain in Istanbul: rainy days and rainfall
A rainy day is a day with at least 1 mm of rain or snow; the amount is what falls in the whole month. Tap a month to select it.
In October, Istanbul has about 9 rainy days with 73 mm of rain in total.
Climate through the year
Long-term monthly averages. Tap a month to see its details.
Temperatures through the year
Average daytime high, night-time low and sea temperature per month.
| Month | Score | Day | Night | Sea | Sun | Rain days | Rain mm |
|---|---|---|---|---|---|---|---|
| JanuaryJan | 17 | 9° | 5° | 9.4° | 4.2 h | 13 | 87 |
| FebruaryFeb | 25 | 9° | 4° | 8.4° | 5.0 h | 12 | 75 |
| MarchMar | 39 | 11° | 6° | 9.0° | 5.9 h | 11 | 72 |
| AprilApr | 70 | 15° | 9° | 11.6° | 7.4 h | 9 | 50 |
| MayMay | 95 | 20° | 14° | 16.1° | 8.9 h | 6 | 33 |
| JuneJun | 97 | 25° | 19° | 21.0° | 10.1 h | 5 | 29 |
| JulyJul | 94 | 28° | 21° | 23.7° | 11.0 h | 3 | 22 |
| AugustAug | 93 | 28° | 22° | 24.4° | 10.2 h | 3 | 21 |
| SeptemberSep | 90 | 24° | 19° | 22.6° | 7.9 h | 7 | 47 |
| OctoberOct | 79 | 19° | 15° | 19.2° | 5.7 h | 9 | 73 |
| NovemberNov | 59 | 15° | 11° | 15.5° | 4.9 h | 9 | 71 |
| DecemberDec | 25 | 11° | 7° | 12.0° | 3.7 h | 13 | 97 |
Climate averages 1996–2025, not a forecast. Data: Copernicus ERA5 / ERA5-Land via Open-Meteo.com (CC BY 4.0), NOAA OISST, GeoNames (CC BY 4.0)
41.01° N, 28.95° E · 39 m · Europe/Istanbul
Best time to visit Istanbul
The best time to visit Istanbul is from May to September. For a beach holiday with the sea above 21 °C, go from June to September. For sightseeing, day trips and hiking, conditions are most comfortable from April to July and from September to October. Rain is most frequent from December to January; the wettest month is December with 97 mm.
Find your perfect month
Tell us what you like and we rate every month in Istanbul for you.
Your best months: June, September
Based on the climate averages; tap a month to see its details.
Which month for what?
Beach & swimming
Jun – Sep
Sea from 21 °C, warm and mostly dry
Sightseeing & hiking
Apr – Jul, Sep – Oct
15–28 °C and not too much rain
Rainy months
Dec – Jan
12 or more rainy days
Snow
Jan – Feb
Snow on 2 or more days
Istanbul month by month
The typical weather for every month at a glance.
17January9° · Sea 9° · 4 h
In January, Istanbul is cold: daytime highs average 9 °C, and nights cool down to about 5 °C. The sea averages 9.4 °C – swimming is only for the hardy. Expect around 4 hours of sunshine a day. Rain is frequent, with about 13 rainy days and 87 mm in total. Snow falls on about 3 days. All in all, January is not an ideal month for a holiday in Istanbul.
Istanbul in January25February9° · Sea 8° · 5 h
In February, Istanbul is cold: daytime highs average 9 °C, and nights cool down to about 4 °C. The sea averages 8.4 °C – swimming is only for the hardy. Expect around 5 hours of sunshine a day. Rain is frequent, with about 12 rainy days and 75 mm in total. Snow falls on about 2 days. All in all, February is not an ideal month for a holiday in Istanbul.
Istanbul in February39March11° · Sea 9° · 6 h
In March, Istanbul is cool: daytime highs average 11 °C, and nights cool down to about 6 °C. The sea averages 9.0 °C – swimming is only for the hardy. Expect around 6 hours of sunshine a day. Rain is frequent, with about 11 rainy days and 72 mm in total. All in all, March is not an ideal month for a holiday in Istanbul.
Istanbul in March70April15° · Sea 12° · 7 h
In April, Istanbul is cool: daytime highs average 15 °C, and nights cool down to about 9 °C. The sea averages 11.6 °C – swimming is only for the hardy. The sun shines for around 7 hours a day. Rain falls on about 9 days, adding up to 50 mm. All in all, April is a good month for a holiday in Istanbul.
Istanbul in April95May20° · Sea 16° · 9 h
In May, Istanbul is mild: daytime highs average 20 °C, and nights cool down to about 14 °C. The sea averages 16.1 °C – swimming is only for the hardy. The sun shines for around 9 hours a day. Rain falls on about 6 days, adding up to 33 mm. All in all, May is an excellent month for a holiday in Istanbul.
Istanbul in May97June25° · Sea 21° · 10 h
In June, Istanbul is warm: daytime highs average 25 °C, and nights cool down to about 19 °C. The sea averages 21.0 °C – refreshing for a swim. With around 10 hours of sunshine a day, there is plenty of sun. Rain falls on about 5 days, adding up to 29 mm. All in all, June is an excellent month for a holiday in Istanbul.
Istanbul in June94July28° · Sea 24° · 11 h
In July, Istanbul is hot: daytime highs average 28 °C, and even at night it stays warm at around 21 °C. The sea averages 23.7 °C – pleasant for swimming. With around 11 hours of sunshine a day, there is plenty of sun. Rain is rare: about 3 days bring 22 mm in total. On about 5 days the thermometer climbs to 30 °C or more. The air is often humid and muggy. All in all, July is an excellent month for a holiday in Istanbul.
Istanbul in July93August28° · Sea 24° · 10 h
In August, Istanbul is hot: daytime highs average 28 °C, and even at night it stays warm at around 22 °C. The sea averages 24.4 °C – pleasant for swimming. With around 10 hours of sunshine a day, there is plenty of sun. Rain is rare: about 3 days bring 21 mm in total. On about 6 days the thermometer climbs to 30 °C or more. The air is often humid and muggy. All in all, August is an excellent month for a holiday in Istanbul.
Istanbul in August90September24° · Sea 23° · 8 h
In September, Istanbul is warm: daytime highs average 24 °C, and nights cool down to about 19 °C. The sea averages 22.6 °C – refreshing for a swim. The sun shines for around 8 hours a day. Rain falls on about 7 days, adding up to 47 mm. All in all, September is an excellent month for a holiday in Istanbul.
Istanbul in September79October19° · Sea 19° · 6 h
In October, Istanbul is mild: daytime highs average 19 °C, and nights cool down to about 15 °C. The sea averages 19.2 °C – bracing, so a wetsuit helps for longer swims. Expect around 6 hours of sunshine a day. Rain falls on about 9 days, adding up to 73 mm. All in all, October is a good month for a holiday in Istanbul.
Istanbul in October59November15° · Sea 16° · 5 h
In November, Istanbul is cool: daytime highs average 15 °C, and nights cool down to about 11 °C. The sea averages 15.5 °C – swimming is only for the hardy. Expect around 5 hours of sunshine a day. Rain is frequent, with about 9 rainy days and 71 mm in total. All in all, November is a so-so month for a holiday in Istanbul.
Istanbul in November25December11° · Sea 12° · 4 h
In December, Istanbul is cool: daytime highs average 11 °C, and nights cool down to about 7 °C. The sea averages 12.0 °C – swimming is only for the hardy. The sun is scarce, with only about 4 hours a day. Rain is frequent, with about 13 rainy days and 97 mm in total. All in all, December is not an ideal month for a holiday in Istanbul.
Istanbul in DecemberPlanning a trip to Istanbul
Getting there
Flying from
- Nonstop flight
- about 3 h 30 min
- Distance
- 2,520 km
- Time zone
- UTC+3
Estimated from the straight-line distance: 30 minutes for take-off and landing plus 830 km/h cruising speed.
Frequently asked questions about Istanbul
When is the best time to visit Istanbul?
The best time to visit Istanbul is from May to September. That is when the holiday weather score, which combines temperature, sea, sunshine and rain, is highest.
How warm is the sea in Istanbul?
The sea temperature in Istanbul ranges from 8.4 °C in February to 24.4 °C in August. It is warm enough for a comfortable swim (20 °C and more) from June to September.
Can you swim in Istanbul in October?
Only if you don't mind cold water: in October the sea averages just 19.2 °C. Comfortable swimming is possible from June to September.
What is the warmest month in Istanbul?
August is the warmest month, with average highs of 28 °C and nights around 22 °C. January is the coolest month at 9 °C.
When does it rain most in Istanbul?
Rain is most frequent from December to January; the wettest month is December with 97 mm. The driest month is August with 21 mm.
How many hours of sunshine does Istanbul get?
Istanbul gets around 2,590 hours of sunshine a year. The sunniest month is July with 11.0 hours a day; in December there are 3.7 hours a day.
What time zone is Istanbul in?
Istanbul uses the time zone Europe/Istanbul, at UTC+3 all year.
How long is the flight from London to Istanbul?
A nonstop flight from London to Istanbul takes about 3 h 30 min, for a straight-line distance of about 2,520 km.
Near Istanbul
Other destinations close by.