In Rotterdam, the second largest city of the Netherlands, the climate is sub-oceanic, humid and rainy, influenced by the North Sea, but also by the Atlantic Ocean, from which disturbances arrive throughout the year, so it has cold (but not freezing) winters, and quite cool summers.
ranges froms 4 °C (39 °F) in January and February to 18 °C (64.5 °F) in July and August.
is relatively abundant, about 880 millimeters (35 inches) per year, but above all, it is common and well distributed over the seasons. However, the rainiest season is autumn, and the least rainy is spring. Rainfall often occurs in the form of short showers or drizzle.
, from December to February, is cold: temperatures are on average a few degrees above freezing (0 °C or 32 °F) during the day, while at night, they are around freezing; wind and humidity often exacerbate the feeling of cold.
When the westerlies blow, the temperature can be quite mild, and can reach 10/12 °C (50/54 °F), but there can be wind and rain.
On the other hand, when the city is affected by cold air masses from Russia, the temperature drops below freezing, for longer or shorter periods, even during the day. During the most intense and prolonged cold waves, rivers and canals can freeze. Generally, the temperature does not drop below -13 °C (9 °F); more rarely, it can drop further. The coldest record is -17.1 °C (1.2 °F) and was set in January 1985.
Snowfalls in Rotterdam are quite frequent, though usually not abundant, and occur in the form of light snow, sometimes, however, snow can accumulate on the ground, and last for many days, if it occurs during cold waves.
, from March to May, is initially cold, with possible snowfalls still in March (and sometimes even in April), and then it gradually becomes milder, although some cold days, with highs around 10 °C (50 °F), can occur even in May, especially in the first half of the month. However, April and May are, albeit slightly, the least rainy and cloudy months of the year.
Typically, by the second half of May, the temperature becomes permanently acceptable, and there can be the first warm days, with highs around 25 °C (77 °F) or even above.
, from June to August, is mild, and the flow of Atlantic fronts does not cease even in this season; the wind blows constantly from the sea, and rainfall is also quite frequent. However, there are pleasant periods, with daytime temperatures between 20 °C and 25 °C (68 °F and 77 °F), but also cooler periods, when they remain below 20 °C (68 °F). At night, it can get a bit cold, in fact, the temperature can drop below 10 °C (50 °F) even in July and August.
At times, hot periods can occur, generally of short duration, which in recent years are becoming more frequent due to global warming, and in which the temperature can exceed 30 °C (86 °F). On the hottest days of the year, the temperature typically reaches 33 °C (91 °F). The heat record is 37 °C (98.5 °F), set in July 2019 and in July 2022.
, from September to November, is initially pleasant, ie in the first half of September, then it gradually becomes more cold, dull, wet, and windy. The first night frosts usually occur in November, but sometimes also in October.
, especially from November to February, when the sun rarely shines. It goes a bit better from May to August, when the weather is variable, and between one disturbance and another, the sun can come out.
near Rotterdam is very cool or cold to swim in even in summer: the water temperature reaches 18 °C (64.5 °F) in August.
to visit Rotterdam runs from mid-May to mid-September, since it is the mildest of the year. July and August are the warmest months. However, it's better to bring a sweatshirt or sweater, a light jacket and an umbrella, for cool and rainy days.
. Here are the average temperatures.
January, the coldest month of the year, is generally a cold month. The average temperature is of
3.8 °C, with a minimum of
1.3 °C and a maximum of
6.4 °C.
On the coldest nights of the month, the temperature usually drops to around
-6.5 °C. However, it dropped to
-14 °C in January 1997.
On the warmest days of the month, the temperature usually reaches around
12 °C. However, it reached
14.1 °C in January 2018.
Precipitation amounts to
70.8 mm, distributed over 13 days.
The day lasts on average 8 hours and 25 minutes.
There are on average 2 hours of sunshine per day. So, the sun shines 27% of the time.
The average humidity is 87%. Hence, the air is normally humid.
The average wind speed is of
19.2 kph.
The average sea temperature is of
7.1 °C. Therefore, the sea is very cold for swimming.
February is generally a quite cold month. The average temperature is of
4.1 °C, with a minimum of
1.1 °C and a maximum of
7.1 °C.
On the coldest nights of the month, the temperature usually drops to around
-5.5 °C. However, it dropped to
-16.3 °C in February 2012.
On the warmest days of the month, the temperature usually reaches around
12.5 °C. However, it reached
18.7 °C in February 2019.
Precipitation amounts to
65.9 mm, distributed over 11 days.
The day lasts on average 10 hours and 0 minutes.
There are on average 3 hours of sunshine per day. So, the sun shines 32% of the time.
The average humidity is 84%. Hence, the air is normally humid.
The average wind speed is of
18.4 kph.
The average sea temperature is of
5.9 °C. Therefore, the sea is very cold for swimming.
March is generally a quite cold month. The average temperature is of
6.5 °C, with a minimum of
2.7 °C and a maximum of
10.3 °C.
On the coldest nights of the month, the temperature usually drops to around
-4 °C. However, it dropped to
-13.4 °C in March 2005.
On the warmest days of the month, the temperature usually reaches around
17 °C. However, it reached
21.4 °C in March 2017.
Precipitation amounts to
56.5 mm, distributed over 10 days.
The day lasts on average 12 hours and 0 minutes.
There are on average 4.5 hours of sunshine per day. So, the sun shines 39% of the time.
The average humidity is 80%. Hence, the air is normally humid.
The average wind speed is of
17.5 kph.
The average sea temperature is of
6.1 °C. Therefore, the sea is very cold for swimming.
April is generally a mild month. The average temperature is of
9.6 °C, with a minimum of
4.8 °C and a maximum of
14.3 °C.
On the coldest nights of the month, the temperature usually drops to around
-1.5 °C. However, it dropped to
-6 °C in April 1996.
On the warmest days of the month, the temperature usually reaches around
22.5 °C. However, it reached
27.5 °C in April 2018.
Precipitation amounts to
42.1 mm, distributed over 9 days.
The day lasts on average 14 hours and 0 minutes.
There are on average 6.5 hours of sunshine per day. So, the sun shines 46% of the time.
The average humidity is 75%. Hence, the air is normally humid.
The average wind speed is of
14.7 kph.
The average sea temperature is of
8.1 °C. Therefore, the sea is very cold for swimming.
May is generally a mild month. The average temperature is of
13 °C, with a minimum of
8.1 °C and a maximum of
17.9 °C.
On the coldest nights of the month, the temperature usually drops to around
1.5 °C. However, it dropped to
-1.4 °C in May 1996.
On the warmest days of the month, the temperature usually reaches around
26.5 °C. However, it reached
31.3 °C in May 2017.
Precipitation amounts to
55.7 mm, distributed over 9 days.
The day lasts on average 15 hours and 40 minutes. So the days are long.
There are on average 7.5 hours of sunshine per day. So, the sun shines 47% of the time.
The average humidity is 74%. Hence, the air is normally humid.
The average wind speed is of
14.3 kph.
The average sea temperature is of
11 °C. Therefore, the sea is very cold for swimming.
June is generally a very mild month. The average temperature is of
15.8 °C, with a minimum of
11 °C and a maximum of
20.6 °C.
On the coldest nights of the month, the temperature usually drops to around
5.5 °C. However, it dropped to
0.5 °C in June 1991.
On the warmest days of the month, the temperature usually reaches around
29.5 °C. However, it reached
33 °C in June 2005.
Precipitation amounts to
68.6 mm, distributed over 10 days.
The day lasts on average 16 hours and 35 minutes. So the days are long. June 21, the summer solstice, is the longest day of the year in the Northern Hemisphere.
There are on average 7 hours of sunshine per day. So, the sun shines 43% of the time.
The average humidity is 75%. Hence, the air is normally humid.
The average wind speed is of
13.9 kph.
The average sea temperature is of
14 °C. Therefore, the sea is very cold for swimming.
July, the warmest month of the year, is generally a very mild month. The average temperature is of
18 °C, with a minimum of
13.4 °C and a maximum of
22.7 °C.
On the coldest nights of the month, the temperature usually drops to around
8.5 °C. However, it dropped to
6.3 °C in July 1993.
On the warmest days of the month, the temperature usually reaches around
31 °C. However, it reached
37.2 °C in July 2019.
Precipitation amounts to
78.6 mm, distributed over 10 days.
The day lasts on average 16 hours and 5 minutes. So the days are long.
There are on average 7 hours of sunshine per day. So, the sun shines 44% of the time.
The average humidity is 76%. Hence, the air is normally humid.
The average wind speed is of
13.5 kph.
The average sea temperature is of
16.5 °C. Therefore, the sea is cold for swimming.
August is generally a very mild month. The average temperature is of
17.9 °C, with a minimum of
13.2 °C and a maximum of
22.6 °C.
On the coldest nights of the month, the temperature usually drops to around
8.5 °C. However, it dropped to
5.2 °C in August 2014.
On the warmest days of the month, the temperature usually reaches around
30 °C. However, it reached
34 °C in August 2018.
Precipitation amounts to
91.9 mm, distributed over 11 days.
The day lasts on average 14 hours and 30 minutes. So the days are long.
There are on average 6.5 hours of sunshine per day. So, the sun shines 45% of the time.
The average humidity is 77%. Hence, the air is normally humid.
The average wind speed is of
12.8 kph.
The average sea temperature is of
18.1 °C. Therefore, the sea is cold for swimming.
September is generally a very mild month. The average temperature is of
15 °C, with a minimum of
10.7 °C and a maximum of
19.3 °C.
On the coldest nights of the month, the temperature usually drops to around
5.5 °C. However, it dropped to
1.6 °C in September 1997.
On the warmest days of the month, the temperature usually reaches around
25.5 °C. However, it reached
32.2 °C in September 2020.
Precipitation amounts to
90.3 mm, distributed over 11 days.
The day lasts on average 12 hours and 35 minutes.
There are on average 5 hours of sunshine per day. So, the sun shines 41% of the time.
The average humidity is 82%. Hence, the air is normally humid.
The average wind speed is of
13.2 kph.
The average sea temperature is of
17.4 °C. Therefore, the sea is cold for swimming.
October is generally a mild month. The average temperature is of
11.2 °C, with a minimum of
7.6 °C and a maximum of
14.9 °C.
On the coldest nights of the month, the temperature usually drops to around
1 °C. However, it dropped to
-5.1 °C in October 1997.
On the warmest days of the month, the temperature usually reaches around
21 °C. However, it reached
26 °C in October 2011.
Precipitation amounts to
87.3 mm, distributed over 12 days.
The day lasts on average 10 hours and 35 minutes.
There are on average 3.5 hours of sunshine per day. So, the sun shines 35% of the time.
The average humidity is 84%. Hence, the air is normally humid.
The average wind speed is of
15.5 kph.
The average sea temperature is of
15.2 °C. Therefore, the sea is cold for swimming.
November is generally a quite mild month. The average temperature is of
7.3 °C, with a minimum of
4.4 °C and a maximum of
10.2 °C.
On the coldest nights of the month, the temperature usually drops to around
-2.5 °C. However, it dropped to
-7.3 °C in November 1998.
On the warmest days of the month, the temperature usually reaches around
15.5 °C. However, it reached
19.3 °C in November 2018.
Precipitation amounts to
87.6 mm, distributed over 14 days.
The day lasts on average 8 hours and 50 minutes.
There are on average 2 hours of sunshine per day. So, the sun shines 25% of the time.
The average humidity is 88%. Hence, the air is normally humid.
The average wind speed is of
15.9 kph.
The average sea temperature is of
12.1 °C. Therefore, the sea is very cold for swimming.
December is generally a quite cold month. The average temperature is of
4.4 °C, with a minimum of
1.9 °C and a maximum of
7 °C.
On the coldest nights of the month, the temperature usually drops to around
-5.5 °C. However, it dropped to
-11.2 °C in December 2010.
On the warmest days of the month, the temperature usually reaches around
12.5 °C. However, it reached
15.1 °C in December 2000.
Precipitation amounts to
86.2 mm, distributed over 14 days.
The day lasts on average 7 hours and 50 minutes. So the days are short. December 21, the winter solstice, is the shortest day of the year in the Northern Hemisphere.
There are on average 2 hours of sunshine per day. So, the sun shines 23% of the time.
The average humidity is 88%. Hence, the air is normally humid.
The average wind speed is of
18 kph.
The average sea temperature is of
9.1 °C. Therefore, the sea is very cold for swimming.