The most comfortable time to visit Istanbul is from September to early November, and again from May to mid June. For sun, aim for late June to early September; for walking, go from late March to May.
When to go five ratings · thirty-six ten-day sections · click a cell to read it
For sun, go from late June to early September. It peaks in late August, at 73. Avoid November to early May for this: it falls to 0, mostly because it is too cool. The clearest skies come in July, when the sky is typically 36% covered at midday (partly cloudy).
The being outside season here runs from September to early November, with a second spell from May to mid June. It peaks in late May, at 80. The weakest stretch is in January, when it drops to 3, mostly because it is too cold.
For walking, go from late March to May, with a second spell from October to early December. It peaks in late April, at 81. Avoid late July to early August for this: it falls to 4, mostly because it is too warm.
The year, measured
The average temperature in Istanbul over the whole year is 16°C. August is the hottest month, with highs of about 29°C; January is the coldest, with lows of about 6°C. The rainy (wet) season in Istanbul runs from November to March, peaking in December with a 30% chance of rain on a given day. The dry season is April to October; August is the driest month, at 5%. Winds in Istanbul are highest in August, averaging 3.8 m/s (14 km/h), and lightest in May, at 2.8 m/s (10 km/h). The prevailing wind is from the N. The clearest skies in Istanbul come in July, when the sky is typically 30% covered; January is the cloudiest month, at 65%.
Month by month Istanbul climate by month: average temperatures year round · click a month to read it
| Month | High | Low | Feels like | Chance of rain | Cloud | Wind | Being outside | Sun | Walking |
|---|---|---|---|---|---|---|---|---|---|
| January | 9°C | 6°C | 5°C | 28% | 65% | 3.1 m/s | 5 | 0 | 39 |
| February | 10°C | 6°C | 6°C | 25% | 62% | 3.1 m/s | 9 | 0 | 46 |
| March | 12°C | 7°C | 8°C | 21% | 59% | 2.9 m/s | 16 | 0 | 57 |
| April | 16°C | 11°C | 13°C | 12% | 50% | 2.9 m/s | 40 | 2 | 75 |
| May | 20°C | 16°C | 19°C | 14% | 53% | 2.8 m/s | 72 | 14 | 72 |
| June | 26°C | 21°C | 26°C | 11% | 40% | 3.0 m/s | 64 | 55 | 28 |
| July | 28°C | 23°C | 29°C | 8% | 30% | 3.5 m/s | 38 | 68 | 10 |
| August | 29°C | 24°C | 29°C | 5% | 35% | 3.8 m/s | 34 | 70 | 7 |
| September | 25°C | 20°C | 24°C | 13% | 42% | 3.2 m/s | 66 | 48 | 34 |
| October | 20°C | 15°C | 19°C | 15% | 49% | 2.8 m/s | 72 | 13 | 71 |
| November | 16°C | 12°C | 13°C | 24% | 58% | 2.9 m/s | 39 | 2 | 75 |
| December | 11°C | 8°C | 8°C | 30% | 62% | 3.0 m/s | 12 | 0 | 55 |
High and low are the warmest and coolest of four readings a day — midnight, 6am, noon and 6pm — so a true overnight low can sit a degree or two under them. Chance of rain, cloud and wind are the day’s average; feels-like and the three ratings (each out of 100: Good from 55, Ideal from 80) are read at midday.
Seasons, and the year in short Istanbul weather by season
Year round, Istanbul has days of about 9°C at their warmest in January, its coolest month, and 29°C in August, its warmest; the coolest hours of the day run from 6°C to 24°C through the year, and the average temperature over the year is 16°C around the clock. Rain is most likely around December and least likely around August. Every figure here is a decade of observations blended into one representative year, so it reads as what this date is usually like, not a forecast for one particular day.
Istanbul weather in winterDecember to February
Winter in Istanbul has typical daily highs of about 10°C and lows of about 7°C, with a 27% chance of rain on a given day.
Istanbul weather in springMarch to May
Spring in Istanbul has typical daily highs of about 16°C and lows of about 11°C, with a 16% chance of rain on a given day.
Istanbul weather in summerJune to August
Summer in Istanbul has typical daily highs of about 28°C and lows of about 23°C, with a 8% chance of rain on a given day.
Istanbul weather in autumnSeptember to November
Autumn in Istanbul has typical daily highs of about 20°C and lows of about 16°C, with a 17% chance of rain on a given day.
When is the rainy season in Istanbul?
The rainy (wet) season in Istanbul runs from November to March, peaking in December with a 30% chance of rain on a given day. The dry season is April to October; August is the driest month, at 5%.
What time of year is Istanbul windiest?
Winds in Istanbul are highest in August, averaging 3.8 m/s (14 km/h), and lightest in May, at 2.8 m/s (10 km/h). The prevailing wind is from the N.
What is the average temperature in Istanbul year round?
The average temperature in Istanbul over the whole year is 16°C. August is the hottest month, with highs of about 29°C; January is the coldest, with lows of about 6°C.
Where to go instead in late January, the weakest time here for being outside
How this is worked out
Every figure is a decade of weather-station observations blended into one typical year, in ten-day sections. The ratings, the chart and the feels-like column are read at midday local solar time. Being outside is the Easy outdoors rating, Sun is Sunbathing and Walking is Active outdoors, each out of 100: Good from 55, Ideal from 80. They describe what a time of year is usually like here, not a forecast. The dotted links open the map at that time of year; set its time of day to midday to see these numbers.