Average Weather in İstanbul Turkey
In İstanbul, the temperature typically varies from 38°F to 85°F over the course of the year, and is rarely below 30°F or above 90°F.
The warm season lasts for 3.2 months, from June 9 to September 15, with an average daily high temperature above 77°F. The hottest day of the year is August 1, with an average high of 85°F and low of 71°F.
The cool season lasts for 3.9 months, from November 28 to March 25, with an average daily high temperature below 55°F. The coldest day of the year is February 6, with an average low of 38°F and high of 47°F.
Average High and Low Temperature
The figure below shows you a compact characterization of the entire year of hourly average temperatures. The horizontal axis is the day of the year, the vertical axis is the hour of the day, and the color is the average temperature for that hour and day.
Average Hourly Temperature
The length of the day in İstanbul varies significantly over the course of the year. In 2017, the shortest day is December 21, with 9 hours, 13 minutes of daylight; the longest day is June 21, with 15 hours, 8 minutes of daylight.
Hours of Daylight and Twilight
The earliest sunrise is at 5:31 AM on June 14, and the latest sunrise is 2 hours, 58 minutes later at 8:29 AM on January 5. The earliest sunset is at 5:35 PM on December 7, and the latest sunset is 3 hours, 5 minutes later at 8:40 PM on June 27.
Daylight saving time (DST) is not observed in İstanbul during 2017.
Sunrise & Sunset with Twilight
In İstanbul, the average percentage of the sky covered by clouds experiences extreme seasonal variation over the course of the year.
The clearer part of the year in İstanbul begins around May 26 and lasts for 4.2 months, ending around October 2. On July 26, the clearest day of the year, the sky is clear, mostly clear, or partly cloudy 96% of the time, and overcast or mostly cloudy 4% of the time.
The cloudier part of the year begins around October 2 and lasts for 7.8 months, ending around May 26. On December 14, the cloudiest day of the year, the sky is overcast or mostly cloudy 58% of the time, and clear, mostly clear, or partly cloudy 42% of the time.
A wet day is one with at least 0.04 inches of liquid or liquid-equivalent precipitation. The chance of wet days in İstanbul varies throughout the year.
The wetter season lasts 6.9 months, from October 3 to May 1, with a greater than 19% chance of a given day being a wet day. The chance of a wet day peaks at 32% on December 13.
The drier season lasts 5.1 months, from May 1 to October 3. The smallest chance of a wet day is 7% on July 12.
Among wet days, we distinguish between those that experience rain alone, snow alone, or a mixture of the two. Based on this categorization, the most common form of precipitation throughout the year is rain alone, with a peak probability of 31% on December 13.
Daily Chance of Precipitation
To show variation within the months and not just the monthly totals, we show the rainfall accumulated over a sliding 31-day period centered around each day in the year. İstanbul experiences significant seasonal variation in monthly rainfall.
Rain falls throughout the year in İstanbul. The most rain falls during the 31 days centered around December 9, with an average total accumulation of 2.9 inches.
The least rain falls around July 22, with and average total accumulation of 0.6 inches.
Average Monthly Rainfall
The sliding 31-day liquid-equivalent quantity of snowfall in İstanbul does not vary significantly over the course of the year, staying within 0.1 inches of 0.1 inches throughout.
Average Liquid-Equivalent Monthly Snowfall
We base the humidity comfort level on the dew point, as it determines whether perspiration will evaporate from the skin, thereby cooling the body. Lower dew points feel drier and higher dew points feel more humid. Unlike temperature, which typically varies significantly between night and day, dew point tends to change more slowly, so while the temperature may drop at night, a muggy day is typically followed by a muggy night.
İstanbul experiences significant seasonal variation in the perceived humidity.
The muggier period of the year lasts for 3.0 months, from June 17 to September 16, during which time the comfort level is muggy, oppressive, or miserable at least 12% of the time. The muggiest day of the year is August 5, with muggy conditions 48% of the time.
The least muggy day of the year is December 11, when muggy conditions are essentially unheard of.
Humidity Comfort Levels
This section discusses the wide-area hourly average wind vector (speed and direction) at 10 meters above the ground. The wind experienced at any given location is highly dependent on local topography and other factors, and instantaneous wind speed and direction vary more widely than hourly averages.
The average hourly wind speed in İstanbul experiences mildly seasonal variation over the course of the year.
The windier part of the year lasts for 8.7 months, from July 7 to March 29, with average wind speeds of more than 5.5 miles per hour. The windiest day of the year is February 4, with an average hourly wind speed of 6.4 miles per hour.
The calmer time of year lasts for 3.3 months, from March 29 to July 7. The calmest day of the year is May 31, with an average hourly wind speed of 4.6 miles per hour.
Average Wind Speed
The predominant average hourly wind direction in İstanbul varies throughout the year.
The wind is most often from the east for 1.8 months, from September 1 to October 27 and for 6.0 days, from November 13 to November 19, with a peak percentage of 45% on September 3. The wind is most often from the north for 2.4 weeks, from October 27 to November 13 and for 9.2 months, from November 25 to September 1, with a peak percentage of 56% on July 28. The wind is most often from the south for 6.0 days, from November 19 to November 25, with a peak percentage of 30% on December 29.
İstanbul is located near a large body of water (e.g., ocean, sea, or large lake). This section reports on the wide-area average surface temperature of that water.
The average water temperature experiences significant seasonal variation over the course of the year.
The time of year with warmer water lasts for 3.5 months, from June 16 to October 1, with an average temperature above 69°F. The day of the year with the warmest water is August 10, with an average temperature of 75°F.
The time of year with cooler water lasts for 3.9 months, from December 18 to April 16, with an average temperature below 52°F. The day of the year with the coolest water is February 17, with an average temperature of 46°F.
Average Water Temperature
This section discusses the total daily incident shortwave solar energy reaching the surface of the ground over a wide area, taking full account of seasonal variations in the length of the day, the elevation of the Sun above the horizon, and absorption by clouds and other atmospheric constituents. Shortwave radiation includes visible light and ultraviolet radiation.
The average daily incident shortwave solar energy experiences very significant seasonal variation over the course of the year.
The brighter period of the year lasts for 3.5 months, from May 8 to August 22, with an average daily incident shortwave energy per square meter above 6.6 kWh. The brightest day of the year is July 7, with an average of 7.9 kWh.
The darker period of the year lasts for 3.7 months, from October 29 to February 19, with an average daily incident shortwave energy per square meter below 2.8 kWh. The darkest day of the year is December 23, with an average of 1.5 kWh.
Average Daily Incident Shortwave Solar Energy
For the purposes of this report, the geographical coordinates of İstanbul are 41.014 deg latitude, 28.950 deg longitude, and 59 ft elevation.
The topography within 2 miles of İstanbul contains only modest variations in elevation, with a maximum elevation change of 322 feet, and an average elevation above sea level of 90 feet. Within 10 miles contains very significant variations in elevation (932 feet). Within 50 miles contains extreme variations in elevation (4,301 feet).
The area within 2 miles of İstanbul is covered by artificial surfaces (69%) and water (22%), within 10 miles by artificial surfaces (47%) and water (36%), and within 50 miles by water (58%) and trees (22%).
This report illustrates the typical weather in İstanbul, based on a statistical analysis of historical hourly weather reports and model reconstructions from January 1, 1980 to December 31, 2016.
Temperature and Dew Point
There are 2 weather stations near enough to contribute to our estimation of the temperature and dew point in İstanbul.
For each station, the records are corrected for the elevation difference between that station and İstanbul according to the International Standard Atmosphere , and by the relative change present in the MERRA-2 satellite-era reanalysis between the two locations.
The estimated value at İstanbul is computed as the weighted average of the individual contributions from each station, with weights proportional to the inverse of the distance between İstanbul and a given station.
All data relating to the Sun's position (e.g., sunrise and sunset) are computed using astronomical formulas from the book, Astronomical Tables of the Sun, Moon and Planets , by Jean Meeus.
All other weather data, including cloud cover, precipitation, wind speed and direction, and solar flux, come from NASA's MERRA-2 Modern-Era Retrospective Analysis . This reanalysis combines a variety of wide-area measurements in a state-of-the-art global meteorological model to reconstruct the hourly history of weather throughout the world on a 50-kilometer grid.
Land Use data comes from the Global Land Cover SHARE database , published by the Food and Agriculture Organization of the United Nations.
Elevation data comes from the Shuttle Radar Topography Mission (SRTM) , published by NASA's Jet Propulsion Laboratory.
Names, locations, and time zones of places and some airports come from the GeoNames Geographical Database .
Time zones for aiports and weather stations are provided by AskGeo.com .