Istanbul weather by month follows a simple pattern. July and August are the hottest, with average highs near 30°C (86°F). January is the coldest and wettest, with highs below 10°C (50°F) and about 16 rainy days. May and September sit in the comfortable middle. Daytime highs there reach about 22 to 26°C.
Last checked: 10 November 2026. Temperature and rain figures are 1950–2025 averages from the Turkish State Meteorological Service (MGM). Daylight hours are our own calculation for Istanbul, not an official figure.
Istanbul weather by month: the official table
Use this table to compare months at a glance. Rainy days are days with measurable rain, and daylight is the time between sunrise and sunset in 2027.
| Month | Average high | Average low | Rainy days | Rain | Daylight on the 15th |
|---|---|---|---|---|---|
| January | 9.6°C (49°F) | 4.2°C (40°F) | 16 | 89 mm | 9h31m |
| February | 10.2°C (50°F) | 4.2°C (40°F) | 14 | 71 mm | 10h36m |
| March | 12.4°C (54°F) | 5.5°C (42°F) | 13 | 62 mm | 11h51m |
| April | 17.4°C (63°F) | 9.2°C (49°F) | 10 | 48 mm | 13h15m |
| May | 22.3°C (72°F) | 13.6°C (56°F) | 8 | 33 mm | 14h26m |
| June | 27.1°C (81°F) | 18.0°C (64°F) | 5 | 28 mm | 15h06m |
| July | 29.7°C (85°F) | 20.5°C (69°F) | 3 | 22 mm | 14h51m |
| August | 29.7°C (85°F) | 20.8°C (69°F) | 4 | 24 mm | 13h51m |
| September | 25.9°C (79°F) | 17.6°C (64°F) | 6 | 40 mm | 12h32m |
| October | 20.6°C (69°F) | 13.7°C (57°F) | 9 | 66 mm | 11h11m |
| November | 16.1°C (61°F) | 9.9°C (50°F) | 11 | 78 mm | 9h55m |
| December | 11.8°C (53°F) | 6.5°C (44°F) | 16 | 99 mm | 9h15m |
These are long-term averages. A single week can run well above or below them. For example, the record for January is 22.4°C and the record for February is −9.0°C, the lowest of any month.
Winter (December to February): cold, wet and dark
Winter highs stay between 9.6 and 11.8°C (49 to 53°F). The nights fall to about 4 to 6.5°C (39 to 44°F). December has the most rain of the year, at 99 mm, and January has the most rainy days, at 16. Daylight is the real limit. On 15 December the sun rises around 08:22 and sets around 17:37, so plan outdoor sights before about 16:30.
This is a good season for museums, mosques and hammams. Our guides to a rainy day in Istanbul, Istanbul in December and snow in Istanbul cover the details.
Spring (March to May): the quickest change
Average highs climb from 12.4°C (54°F) in March to 22.3°C (72°F) in May. Rain drops from 12.6 rainy days in March to 7.5 in May. Daylight grows fast too. It stretches from 11h51m in mid-March to 14h26m in mid-May. Pack layers, because mornings stay cool and afternoons in the sun feel warmer.
Summer (June to August): hot, dry and long days
June to August bring the least rain, with only 3.5 to 5.4 rainy days a month. Highs average 27.1°C (81°F) in June and 29.7°C (86°F) in July and August. The record is 40.6°C (105°F) in July. Daylight lasts about 15 hours, so you can sightsee in the early morning and again after 18:00. Rest indoors in the middle of the day.
Autumn (September to November): warm start, wet finish
September still feels like summer, with a 25.9°C (79°F) average high. October cools to 20.6°C (69°F) and brings 9.5 rainy days. By November the high is 16.1°C (61°F) with 11.3 rainy days. Our Istanbul in November guide shows how that month plays out.
What to pack for each season
| Season | Bring |
|---|---|
| Winter | Waterproof jacket, warm layers, shoes with grip for wet cobbles, a small umbrella |
| Spring | Light jacket, sweater, rain shell, comfortable walking shoes |
| Summer | Breathable clothing, sunscreen, hat, a scarf for mosques, a refillable bottle |
| Autumn | Layers, rain jacket from October, closed shoes |
Which month should you choose?
May and September give the best balance of warmth and dry days. April or October suit you if you want fewer hot hours and fair odds of sun. January and February work best when low prices matter more than the weather. For a first visit, our first-time visitor tips add more planning help.
Istanbul weather questions
What is the coldest month in Istanbul?
January and February have the lowest average highs, at 9.6°C and 10.2°C. February holds the record low of −9.0°C.
What is the rainiest month in Istanbul?
December has the most rain, at 99.2 mm. January has the most rainy days, at 16.
Is Istanbul hot in summer?
Yes. July and August highs average 29.7°C (86°F), and the all-time record is 40.6°C (105°F). Days are dry and long.
