İzmit climate
İzmit (Turkey) has a humid subtropical climate (Köppen Cfa). The average temperature over the year is 15 °C58 °F, and about 734 mm29 in of precipitation falls in an average year.
Temperature by month
Precipitation by month
İzmit climate table
| Month | High °C°F | Low °C°F | Mean °C°F | Precip. mmin | Frost days |
|---|---|---|---|---|---|
| Jan | 948 | 134 | 541 | 863.4 | 12 |
| Feb | 1151 | 236 | 643 | 662.6 | 10 |
| Mar | 1457 | 439 | 948 | 652.6 | 5 |
| Apr | 1864 | 745 | 1254 | 481.9 | 0 |
| May | 2373 | 1253 | 1763 | 512.0 | 0 |
| Jun | 2780 | 1661 | 2271 | 652.6 | 0 |
| Jul | 3086 | 1966 | 2476 | 341.3 | 0 |
| Aug | 3087 | 2067 | 2577 | 381.5 | 0 |
| Sep | 2679 | 1661 | 2170 | 552.2 | 0 |
| Oct | 2169 | 1253 | 1661 | 712.8 | 0 |
| Nov | 1660 | 744 | 1152 | 632.5 | 1 |
| Dec | 1151 | 337 | 744 | 923.6 | 9 |
| Year | 3087 | 134 | 1558 | 73429 | 38 |
“Year” row: highest monthly high, lowest monthly low, annual mean and annual total. Frost days are for the whole grid cell.
| Month | Humid. | Cloud | Solar | Daylight |
|---|---|---|---|---|
| Jan | 84% | 73% | 1.6 | 9:33 |
| Feb | 82% | 72% | 2.4 | 10:35 |
| Mar | 78% | 65% | 3.5 | 11:49 |
| Apr | 76% | 59% | 4.9 | 13:15 |
| May | 77% | 53% | 6.1 | 14:26 |
| Jun | 75% | 39% | 7.0 | 15:05 |
| Jul | 71% | 25% | 7.3 | 14:49 |
| Aug | 70% | 26% | 6.4 | 13:47 |
| Sep | 73% | 40% | 4.8 | 12:24 |
| Oct | 79% | 53% | 3.2 | 11:02 |
| Nov | 81% | 57% | 2.2 | 9:50 |
| Dec | 84% | 70% | 1.5 | 9:16 |
Humid. = average relative humidity at 2 m; cloud = average cloud amount; solar = average daily solar energy reaching the ground in kWh/m² (all-sky); daylight in hours:minutes, calculated for the 15th of each month.
What the climate of İzmit is like
The warmest month is August, with an average high of 30 °C87 °F and a low of 20 °C67 °F. The coldest is January, when highs average 9 °C48 °F and lows 1 °C34 °F. Seasons are strongly marked: the warmest month is on average 19.9 °C35.8 °F warmer than the coldest.
Annual precipitation is moderate at about 734 mm29 in. The wettest three-month stretch is December–February, which brings 33% of the annual total. The wettest month is December (92 mm3.6 in), the driest is July (34 mm1.3 in).
Relative humidity ranges from 70% in August to 84% in January. The clearest skies (lowest average cloud amount, 25%) are typical of July. Average wind speed near the ground ranges from 7 km/h (4 mph) in May to 9 km/h (6 mph) in February. Daylight lasts from about 9.3 hours in December to 15.1 hours in June.
Best time to visit İzmit
Based on these averages, the most comfortable months for sightseeing and outdoor activities are May–July and September and October: average highs of 21 °C69 °F to 30 °C86 °F with 34 mm1.3 in to 71 mm2.8 in of precipitation per month.
The most challenging month is January, which is cold, with average highs of 9 °C48 °F.
Comfort score: months are ranked by how close they come to an average high of 21–28 °C (70–82 °F), lows above 5 °C (41 °F), little precipitation and moderate humidity. The best-ranked months of each place are recommended, even where none meets all of these. These are general rules of thumb applied to long-term averages.
What to pack for İzmit
- Winter (December–February) — highs 948 to 11 °C51 °F, lows 134 to 3 °C37 °F, about 81 mm3.2 in of precipitation a month. Pack a warm coat, layers and closed shoes.
- Spring (March–May) — highs 1457 to 23 °C73 °F, lows 439 to 12 °C53 °F, about 55 mm2.2 in of precipitation a month. Pack light layers — T-shirts plus a light sweater or jacket and an extra layer for the cooler mornings and evenings.
- Summer (June–August) — highs 2780 to 30 °C87 °F, lows 1661 to 20 °C67 °F, about 46 mm1.8 in of precipitation a month. Pack light summer clothes such as T-shirts, shorts or light dresses.
- Autumn (September–November) — highs 1660 to 26 °C79 °F, lows 744 to 16 °C61 °F, about 63 mm2.5 in of precipitation a month. Pack light layers — T-shirts plus a light sweater or jacket.
How İzmit compares
Compared with Adapazarı, about 40 km to the east, İzmit is on average 0.4 °C0.7 °F cooler and receives a similar amount of precipitation. The difference is largest in November (0.9 °C1.6 °F cooler).
Of the 87 places in Turkey covered by World Climates, İzmit is the 52nd warmest by annual mean temperature and the 9th wettest by annual precipitation. See all of them on the Turkey climate page.
Places in other countries with the most similar temperature and rainfall pattern: Novorossiysk (Russia, Cfa), Florence (Italy, Cfa) and Arezzo (Italy, Csa).
The same NASA POWER grid cell also contains Derince (pop. 125,485). Their long-term averages in this dataset are essentially the same as for İzmit, so they do not have separate pages.
Nearby places
- Adapazarı 40 km · 15 °C59 °F · 725 mm29 in
- Maltepe 68 km · 14 °C58 °F · 673 mm26 in
- Ümraniye 73 km · 15 °C58 °F · 673 mm26 in
- Üsküdar 82 km · 15 °C60 °F · 624 mm25 in
- İnegol 84 km · 15 °C59 °F · 610 mm24 in
- Istanbul 87 km · 15 °C60 °F · 624 mm25 in
- Bursa 97 km · 16 °C60 °F · 642 mm25 in
- Küçükçekmece 101 km · 15 °C59 °F · 624 mm25 in
Frequently asked questions
What is the warmest month in İzmit?
August is the warmest month in İzmit, with an average high of 30 °C (87 °F) and an average low of 20 °C (67 °F).
What is the coldest month in İzmit?
January is the coldest month, with an average high of 9 °C (48 °F) and an average low of 1 °C (34 °F).
When does it rain the most in İzmit?
December is the wettest month with about 92 mm (3.6 in) of precipitation; July is the driest with about 34 mm (1.3 in).
What is the best time to visit İzmit?
Judging by long-term averages, the most comfortable months are May–July and September and October.
About this data
All figures are 25-year averages (January 2001 – December 2025) from the NASA POWER project. Temperature, humidity, wind and precipitation come from the MERRA-2 reanalysis (precipitation is the bias-corrected MERRA-2 product), cloud and solar values from CERES satellite data. They describe a grid cell of roughly 50–70 km, not a single weather station, so they can differ from airport records — most of all on coasts, in mountains and for rainfall. Average highs and lows are the monthly mean temperature plus/minus half of the average daily temperature range. Counts of rainy days are not part of this dataset.
The grid cell’s average elevation is 162 m, while İzmit lies at about 19 m. Temperatures on this page were therefore adjusted by +0.9 °C1.7 °F using the standard lapse rate of 6.5 °C per 1,000 m.