Istanbul weather in April
In April, Istanbul has daytime highs averaging 15 °C, nights around 8.6 °C, with 8.0 wet days, and a sea temperature of 11 °C. Figures are 1991–2020 climate normals.
- 15.1°C Average high
- 8.6°C Average low
- 8.0days Wet days
- 47mm Rainfall
- 11.3°C Sea temperature
- 13h Daylight
Daily temperatures through April
How April develops
Averages for the first, middle and last part of the month, from daily 1991–2020 normals. Chance of rain is the share of years in which that calendar day recorded more than 1 mm.
| Days | Avg high | Avg low | Chance of rain |
|---|---|---|---|
| 1–10 April | 13.5 °C | 7.3 °C | 32 % |
| 11–20 April | 15.4 °C | 8.8 °C | 27 % |
| 21–30 April | 16.2 °C | 9.7 °C | 21 % |
- Average highs rise from 13.5 °C early in April to 16.2 °C by the end of it.
- Rain is most likely over days 1–10 of April (32 % of days) and least likely over days 21–30 (21 %).
What to expect
| Measure | Typical April | Share of the month |
|---|---|---|
| Days above 25 °C | 0.1 of 30 | 0 % |
| Days above 30 °C | 0 of 30 | 0 % |
| Days below 0 °C | 0 of 30 | 0 % |
| Days with more than 1 mm rain | 8.0 of 30 | 27 % |
Conditions in April
| Measure | Average |
|---|---|
| Mean temperature | 12 °C |
| Record high (1991–2020) | 27 °C |
| Record low (1991–2020) | 1.5 °C |
| Relative humidity | 76 % |
| Wind speed | 20 km/h |
| Cloud cover | 53 % |
April compared with the months around it
| Month | Avg high | Rainfall | Cloud |
|---|---|---|---|
| February | 8.8 °C | 71 mm | 64 % |
| March | 11.0 °C | 72 mm | 59 % |
| April | 15.1 °C | 47 mm | 53 % |
| May | 20.0 °C | 36 mm | 45 % |
| June | 24.9 °C | 34 mm | 30 % |
See all twelve months for Istanbul
- April is the 7th warmest month here.
- It is the 6th driest month of the year.
- It ranks 7th for least cloud cover.
- Days last about 13 hours from sunrise to sunset.
- It rains on 8.0 of 30 days — 27 % of the month.
- Nights are about 6.4 °C cooler than the middle of the day.
- The hottest April day on record since 1991 reached 27 °C, 12 °C above the usual daytime high.
- Beach score: 18 / 100 — see how this is calculated.
Nearby destinations in April
| Destination | Avg high | Wet days | Sea |
|---|---|---|---|
| Istanbul | 15 °C | 8.0 | 11 |
| Bağcılar | 15 °C | 8 | 11 |
| Esenyurt | 14 °C | 7 | 12 |
| Arnavutköy | 15 °C | 7 | 10 |
| Gebze | 16 °C | 9 | 11 |
| İzmit | 18 °C | 11 | – |
| Bursa | 18 °C | 11 | 12 |
| Çorlu | 16 °C | 8 | – |
QuestionsApril in Istanbul, answered
How warm is Istanbul in April?
Daily highs average 15 °C and nights fall to about 8.6 °C, a spread of 6.4 °C between afternoon and dawn. That makes April the 8th warmest month of the year here.
Does it rain much in Istanbul in April?
April averages 47 mm of rain, spread over about 8 of the 30 days — 27 % of the month. Cloud cover averages 53 % of the sky.
Is the sea warm enough to swim in April?
The sea averages 11 °C off Istanbul in April. Most people find water below 20 °C bracing and above 25 °C comfortable for a long swim; this figure is a monthly surface average, so a sheltered bay on a still afternoon can be warmer.
How long are the days in April?
Istanbul averages 13 hours between sunrise and sunset in April. Day length is computed from latitude and date, so it is exact rather than modelled — but it says nothing about how much of that time is sunny.
Data sources and method
- ERA5 / ERA5-Land reanalysis — Copernicus Climate Change Service (C3S), ECMWF. Copernicus Licence
- Open-Meteo — Open-Meteo.com. CC BY 4.0
- NOAA OISST v2.1 — NOAA Physical Sciences Laboratory. Public domain
- GeoNames — GeoNames.org. CC BY 4.0
- Normal period
- 1991–2020
- Dataset version
- era5-1991-2020-scores1.1
- Last processed
Measured values come from ERA5 reanalysis and are reproduced unchanged. Calculated by us: daylight hours, beach and comfort scores, monthly rankings, threshold day counts, chance of a wet day by date, ten-day averages within the month. Full formulas are on the methodology page.
Contains modified Copernicus Climate Change Service information 2026. Neither the European Commission nor ECMWF is responsible for any use that may be made of the Copernicus information or data it contains.