May weather forecastIstanbul, Turkey

Ships along the coast of the city port of Istanbul, Turkey

May

Weather in May

With spring in its prime, May ushers in a significantly warmer climate to Istanbul, rendering a renewed vigor to the historic city. The average high temperatures reach a balmy 20.9°C (69.6°F) in May, paving the way for outdoorsiness. An increase in both sunshine and daylight hours allows city dwellers to indulge in evening strolls in Istanbul’s majestic parks and streets. May’s weather in Istanbul facilitates the growth of vivid flowers, which embellish the city with vibrant colors and a sense of freshness. Another defining feature of May is the sharp decline in the average cloud coverage, revealing Istanbul's brilliant blue skies.

Temperature

Istanbul in May experiences an increase in the average high-temperature, moving from April's moderate 15.3°C (59.5°F) to an agreeable 20.9°C (69.6°F). Istanbul's nighttime temperature in May drops to an average of 15.1°C (59.2°F).

Humidity

In Istanbul, the average relative humidity in May is 70%.

Rainfall

In Istanbul, during May, the rain falls for 11.8 days and regularly aggregates up to 38mm (1.5") of precipitation. Throughout the year, in Istanbul, there are 130.7 rainfall days, and 400mm (15.75") of precipitation is accumulated.

Snowfall

In Istanbul, snow does not fall in April through November.

Sea temperature

In Istanbul, in May, the average water temperature is 15.7°C (60.3°F).
Note: Most individuals do not find swimming at 15.7°C (60.3°F) to be enjoyable. As the water temperature declines below 21°C (69.8°F), maintaining control over one's breathing becomes harder.

Daylight

In May, the average length of the day in Istanbul, Turkey, is 14h and 29min.
On the first day of the month, sunrise is at 06:01 and sunset at 20:00. On the last day of May, in Istanbul, sunrise is at 05:34 and sunset at 20:29 +03.

Sunshine

In Istanbul, the average sunshine in May is 10.5h.

UV index

In May, the average daily maximum UV index in Istanbul is 5. A UV Index value of 3 to 5 symbolizes a moderate threat to health from exposure to the Sun's UV radiation for the average person.
Note: The maximum daily UV index of 5 in May converts into the following recommendations:
Exercise prevention - Warding off sunburn is urged. The Sun's most harmful UV rays are emitted around midday; avoid staying outdoors for long during this time. Sunglasses that guard against UVA and UVB rays are pivotal in minimizing sun-induced ocular damage.

Updated: Jan 24, 2024
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

In Istanbul, 20.9°C (69.6°F) is the average high-temperature and 15.1°C (59.2°F) is the average low-temperature during May.

The average relative humidity in May in Istanbul, Turkey, is 70%.

In May, in Istanbul, the rain falls for 11.8 days. Throughout May, 38mm (1.5") of precipitation is accumulated.

In Istanbul, Turkey, snow does not fall in April through November.

In May, the average sea temperature in Istanbul is 15.7°C (60.3°F). For swimming, a surface water temperature of 15.7°C (60.3°F) is not enjoyable for the majority. It is not considered safe, as controlling breathing becomes progressively more difficult as water temperature decreases below 21°C (69.8°F).

In May, the average day length in Istanbul is 14h and 29min.

On the first day of May in Istanbul, Turkey, sunrise is at 06:01 and sunset at 20:00. On the last day of the month, sunrise is at 05:34 and sunset at 20:29 +03.

In Istanbul, the average sunshine duration in May is 10.5h.

In May, the average daily maximum UV index in Istanbul, Turkey, is 5. A UV Index value of 3 to 5 symbolizes a moderate vulnerability from exposure to Sun's UV rays.

Today

Tomorrow

Long-term

Year J F M A May J J A S O N D

Apr

May

Jun

Average high temperature

15.3°C

20.9°C

25.4°C

Average low temperature

Average pressure

Average wind speed

Average max. wind speed

16.2km/h

15.1km/h

15.9km/h

Average wind speed gusts

Average humidity

Average rainfall

Average rainfall days

Average snowfall

Average snowfall days

Average sea temperature

Average daylight

Average sunshine

Average sunshine days

15.7

17.9

Average UV index

Average cloud cover

Average visibility

Average temperature in May
Istanbul, Turkey

Average high temperature in May: 20.9°C

The warmest month (with the highest average high temperature) is July (27.9°C).
The month with the lowest average high temperature is January (8.5°C).

Average low temperature in May: 15.1°C

The month with the highest average low temperature is August (23.3°C).
The coldest month (with the lowest average low temperature) is January (5.3°C).

Average pressure in May
Istanbul, Turkey

Average pressure in May: 1013.4mbar

The month with the highest atmospheric pressure is December (1019.7mbar).
The month with the lowest atmospheric pressure is July (1011.7mbar).

Average wind speed in May
Istanbul, Turkey

Average wind speed in May: 14km/h

The windiest month (with the highest average wind speed) is August (20.5km/h).
The calmest month (with the lowest average wind speed) is May (14km/h).

Average humidity in May
Istanbul, Turkey

Average humidity in May: 70%

The month with the highest relative humidity is February (78%).
The months with the lowest relative humidity are June and July (67%).

Average rainfall in May
Istanbul, Turkey

Average rainfall in May: 38mm

The wettest month (with the highest rainfall) is December (52mm).
The driest month (with the least rainfall) is August (11mm).

Average rainfall days in May
Istanbul, Turkey

Average rainfall days in May: 11.8 days

The month with the highest number of rainy days is March (14.3 days).
The month with the least rainy days is August (3.8 days).

Average snowfall in May
Istanbul, Turkey

Average snowfall in May: 0mm

The month with the highest snowfall is January (24mm).
The months with the least snowfall are April, May, June, July, August, September, October and November (0mm).

Average snowfall days in May
Istanbul, Turkey

Average snowfall days in May: 0 days

The month with the highest number of snowfall days is January (3.7 days).
The months with the least snowfall days are April, May, June, July, August, September, October and November (0 days).

Average sea temperature in May
Istanbul, Turkey

Average sea temperature in May: 15.7°C

The best month for swimming (with the highest average sea temperature) is August (24.9°C).
The coldest month (with the lowest average sea temperature) is February (7.8°C).

Average daylight in May /
Average sunshine in May
Istanbul, Turkey

Average daylight in May: 14h and 30min

The month with the longest days is June (Average daylight: 15h and 6min).
The month with the shortest days is December (Average daylight: 9h and 18min).

Average sunshine in May: 10h and 30min

The month with the most sunshine is July (Average sunshine: 11h and 48min).
The month with the least sunshine is December (Average sunshine: 4h and 48min).

Average sunshine days in May
Istanbul, Turkey

Average sunshine days in May: 17 days

The month with the most sunshine days is August (25.5 days).
The month with the least sunshine days is February (12.6 days).

Average UV index in May
Istanbul, Turkey

Average UV index in May: 5

The month with the highest UV index is July (UV index 7).
The months with the lowest UV index are January, February and December (UV index 2).

Average cloud cover in May
Istanbul, Turkey

Average cloud cover in May: 27

The month with the most cloud cover is January (Cloud cover 55).
The months with the least cloud cover are July and August (Cloud cover 12).

Average visibility in May
Istanbul, Turkey

Average visibility in May: 10km

The months with the highest visibility are March, April, May, June, July, August, September, October, November and December (10km).
The months with the lowest visibility are January and February (9km).