Climate Insights for Istanbul

The climate in Istanbul is temperate. The average annual temperature is 16°C and approximately 690mm of precipitation falls per year. January is the wettest month, receiving around 105mm of rainfall. Istanbul is in the Northern Hemisphere. Summer begins at the end of June and lasts through September. The summer months are: August, July, June. The coldest months are January, February, March, when temperatures can drop to 5°C. Light snow can occur between January and December.

Temperatures in Istanbul vary considerably across the year, with a 23°C difference between the coldest and warmest months. The warmest month is August, when average highs reach 28°C and the mean temperature sits around 25°C. January is the coolest month, with minimum temperatures around 5°C and an average of 7°C. Daily temperature variation is modest, with an average difference of 5°C between highs and lows. The sharpest temperature change occurs between May and June, with a 5°C shift in average temperatures.

Istanbul is a relatively dry area, receiving approximately 690mm of precipitation annually, which averages out to around 57mm per month. The wettest month is January, averaging 105mm of rainfall. December and November also tend to see above-average precipitation. The driest month is August, with just 15mm. That's 90mm less than January, the wettest month. Rainfall is heavily concentrated in certain months, creating a distinct wet and dry season. Visitors should plan around these patterns, as the difference between peak and low months is dramatic. Light snowfall can occur between January and December, totalling around 26cm annually. January is the snowiest month with approximately 14cm.

Istanbul is moderately windy, with an average annual wind speed of 22km/h. For context, sustained winds below 12km/h are generally light, while anything above 25km/h is considered strong. The windiest month is January, averaging 24km/h, noticeable enough to affect lighter outdoor activities. The calmest conditions occur in May, with average winds dropping to 19km/h, making it an ideal period for wind-sensitive activities. Wind conditions are fairly consistent throughout the year, varying by only 5km/h between the calmest and windiest months.

It is currently spring in Istanbul, which began on March 20, 2026. Istanbul is in the Northern Hemisphere, where spring begins in March, summer in June, autumn in September, and winter in December. The warmest period peaks in August at around 28°C, while the coldest stretch bottoms out in January near 5°C. Summer is next, beginning on June 21, 2026 — 90 days from now.

The best time to visit Istanbul is during May, June, July, September and October, when the weather is most comfortable for travellers. During these months, average temperatures hover around 21°C with modest rainfall averaging 39mm per month. By contrast, August can be uncomfortably hot with highs reaching 28°C, while January is the coldest period with lows dropping to 5°C. A light rain jacket is recommended, though showers are generally brief and shouldn't disrupt your plans.

The table below shows monthly climate averages for Istanbul based on historical weather data. Min and max temperatures represent typical overnight lows and afternoon highs for each month, shown in degrees Celsius (°C). Precipitation is measured in millimetres (mm) and indicates the average total rainfall per month. Snow is measured in centimetres (cm) and reflects average monthly snowfall accumulation. Wind speed is the average sustained speed in kilometres per hour (km/h). All values are based on averages from over 10 years of historical weather data. The current month is highlighted for quick reference.