Weather and climate in Bilbao (Basque Country)

Bilbao, the largest city in the Basque Country, has a temperate oceanic climate, with mild, rainy winters and mild or pleasantly warm summers. We are in the north of Spain, where the climate is much cooler and more humid than in the rest of the country.
The wind blows frequently from the ocean, and can be strong, especially in the cold half of the year. On the other hand, the warm and dry southerly wind, which descends from the Cantabrian Mountains, can cause sudden increases in temperature due to the foehn effect.
At night, fog can form, especially in autumn, and a little less frequently in spring.
Bilbao lies in a valley, 15 kilometers (9 miles) long, along the so-called Bilbao Estuary, formed by the confluence of the Nervión and Ibaizábal rivers. The historic center is located 10 km (6 mi) away from the coast, then over the centuries the city has developed until it reached the coast.
The average temperature of the coldest month (January) is of 9.5 °C (49 °F), that of the warmest month (August) is of 21.5 °C (70.5 °F). Here are the average temperatures.

Precipitation is quite abundant, in fact, it amounts to 1,100 millimeters (44 inches) per year, with a maximum from October to April and a minimum (not very evident) in summer. Here is the average precipitation.

Winter, from December to February, is mild and rainy. Atlantic disturbances regularly pass over northern Spain, bringing rain and cloudy skies.
With the wind from the south, the temperature can exceed 20 °C (68 °F) even in the middle of winter.
There may also be cold spells, although they are quite rare. In these cases, there may be some cold days, with highs around 5 °C (41 °F).
Moreover, some light frosts may occur at night. On the coldest nights of the year, the temperature generally drops to -2/-3 °C (27/28 °F).
The cold record, -8.5 °C (16.5 °F), dates back to February 1963. Other very low values were -8 °C (17.5 °F) in February 1956, -7.5 °C (18.5 °F) in December 1962, -6.5 °C (20.5 °F) in January 1985, and -6 °C (21 °F) in December 2001.
Snow in Bilbao is rare. During cold spells, some snowfalls may occur, but there is rarely accumulation because the north wind comes from the sea, so the temperature tends to stay above freezing.
However, some fairly heavy snowfall has occurred in the past. In February 1954, the snow thickness reached 35 cm (13.5 in). In February 1963, almost 30 cm (12 in) of snow fell, before recording the coldest record. In January 1985, there were two snowfalls, the main one of 25 cm (10 in).

Spring, from March to May, is cool, cloudy and rainy. Wind and humidity can increase the feeling of cold. When the wind blows from the south, there may be sudden increases in temperature, with the first warm periods, maybe only for a day or two.

In Summer, from June to August, generally, the days are pleasantly warm, while nights are cool. Some Atlantic disturbances, which can bring rainy and cool weather, with highs around 20 °C (68 °F), can affect this area even in summer, although more rarely than in the other seasons.
However, the official number of rainy days can be misleading, because even in summer, brief showers often occur, or drizzle, which perhaps escape the statistics (because they do not reach the amount of one liter per square meter).
Even though the average temperatures are not high, hot days can occur: on average, the temperature exceeds 30 °C (86 °F) for sixteen days a year, and 35 °C (95 °F) for three days a year. Indeed, every so often, scorching days can occur, with highs near 40 °C (104 °F), due to the aforementioned down-slope wind from the south, but even in these cases, the temperature usually drops below 20 °C (68 °F) at night, because sooner or later the sea breeze blows again.
The highest recorded temperature is 42 °C (107.5 °F), recorded in July 1947 and in August 2003. In 2019, it reached 41 °C (106 °F) in late June, and in 1988, 41.5 °C (106.5 °F) in September.

Autumn, from September to November, is initially mild or pleasantly warm, and then gradually becomes more cool and rainy. Indeed, September still resembles a summer month, the average maximum being higher than that of June and similar to that of July.
With the south wind coming down from the mountains, there can be very mild or even warm days: the temperature can reach 30 °C (86 °F) in October and 25 °C (77 °F) in November.
Instead, on clear nights, fog can form.



Bilbao does not get a lot of sun, since cloudy skies are predominant, not only in the long period when Atlantic depressions are frequent, ie from October to May, but also in summer, because even when it is not raining, a cloud cover often forms, due to the contrast between the cold sea and the warmer air that flows above it.
With just 1,600 hours of sunshine per year, we are on par with London. Here are the average sunshine hours per day.

The sea near Bilbao is very cool, if not a bit cold, even in midsummer, since the water temperature reaches at most 21/22 °C (70/72 °F) from July to September.

Best Time

The best time to visit Bilbao is from June to mid-September, since it is the warmest and driest period of the year. It's better to bring a sweatshirt and a light jacket for the evening and for rainy days; an umbrella can be useful too. But you have to be ready to uncover, in case the hot south wind blows.

Back to the Basque Country.

Bilbao - Weather by month

Based on the period 1991-2020

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January, the coldest month of the year, is generally a mild month. The average temperature is of 9.5 °C (49 °F), with a minimum of 5.4 °C (41.6 °F) and a maximum of 13.7 °C (56.6 °F).
On the coldest nights of the month, the temperature usually drops to around -1 °C (30 °F). However, it dropped to -5 °C (23 °F) in January 2000.
On the warmest days of the month, the temperature usually reaches around 20.5 °C (69 °F). However, it reached 23.4 °C (74.1 °F) in January 1999.
Precipitation amounts to 120 mm (4.7 in), distributed over 13 days.
The day lasts on average 9 hours and 25 minutes.
There are on average 2.5 hours of sunshine per day. So, the sun shines 29% of the time.
The average humidity is 74%. Hence, the air is normally humid.
The average wind speed is 10 kph (6 mph).
The average sea temperature is of 13 °C (55 °F). Therefore, the sea is very cold for swimming.

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February is generally a mild month. The average temperature is of 9.7 °C (49 °F), with a minimum of 5 °C (41 °F) and a maximum of 14.3 °C (57.8 °F).
On the coldest nights of the month, the temperature usually drops to around -1 °C (30.5 °F). However, it dropped to -5.7 °C (21.7 °F) in February 1993.
On the warmest days of the month, the temperature usually reaches around 22 °C (71.5 °F). However, it reached 27 °C (80.6 °F) in February 2004.
Precipitation amounts to 85 mm (3.3 in), distributed over 11 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 32% of the time.
The average humidity is 71%. Hence, the air is normally humid.
The average wind speed is 11 kph (7 mph).
The average sea temperature is of 12.5 °C (54.5 °F). Therefore, the sea is very cold for swimming.

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March is generally a mild month. The average temperature is of 11.8 °C (53 °F), with a minimum of 6.7 °C (44.1 °F) and a maximum of 16.8 °C (62.3 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around 0.5 °C (33 °F). However, it dropped to -4 °C (24.8 °F) in March 2005.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 26 °C (79 °F). However, it reached 29 °C (84.2 °F) in March 2003.
Precipitation amounts to 90 mm (3.5 in), distributed over 11 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 35% of the time.
The average humidity is 68%.
The average wind speed is 11 kph (7 mph).
The average sea temperature is of 12.5 °C (54.5 °F). Therefore, the sea is very cold for swimming.

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April is generally a mild month. The average temperature is of 13.2 °C (56 °F), with a minimum of 8.2 °C (46.8 °F) and a maximum of 18.3 °C (64.9 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around 2.5 °C (36 °F). However, it dropped to -1.2 °C (29.8 °F) in April 1991.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 28 °C (82 °F). However, it reached 34 °C (93.2 °F) in April 2010.
Precipitation amounts to 105 mm (4.1 in), distributed over 13 days.
The day lasts on average 13 hours and 30 minutes.
There are on average 4.5 hours of sunshine per day. So, the sun shines 34% of the time.
The average humidity is 70%.
The average wind speed is 11 kph (7 mph).
The average sea temperature is of 13 °C (56 °F). Therefore, the sea is very cold for swimming.

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May is generally a very mild month. The average temperature is of 16.2 °C (61 °F), with a minimum of 11.1 °C (52 °F) and a maximum of 21.4 °C (70.5 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around 5 °C (41 °F). However, it dropped to 2.7 °C (36.9 °F) in May 2016.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 32 °C (89.5 °F). However, it reached 38 °C (100.4 °F) in May 2005.
Precipitation amounts to 80 mm (3.1 in), distributed over 11 days.
The day lasts on average 14 hours and 40 minutes. So the days are long.
There are on average 5.5 hours of sunshine per day. So, the sun shines 37% of the time.
The average humidity is 71%. Hence, the air is normally humid.
The average wind speed is 10 kph (6 mph).
The average sea temperature is of 15 °C (59.5 °F). Therefore, the sea is cold for swimming.

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June is generally a warm month. The average temperature is of 19.0 °C (66 °F), with a minimum of 13.9 °C (57.1 °F) and a maximum of 24 °C (75.2 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around 9 °C (48 °F). However, it dropped to 6 °C (42.8 °F) in June 1992.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 35 °C (95.5 °F). However, it reached 41 °C (105.8 °F) in June 2011.
Precipitation amounts to 60 mm (2.4 in), distributed over 7 days.
The day lasts on average 15 hours and 20 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 6 hours of sunshine per day. So, the sun shines 39% of the time.
The average humidity is 73%. Hence, the air is normally humid.
The average wind speed is 9 kph (6 mph).
The average sea temperature is of 18.5 °C (65 °F). Therefore, the sea is very cool for swimming.

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July is generally a warm month. The average temperature is of 21.0 °C (70 °F), with a minimum of 16 °C (60.9 °F) and a maximum of 25.9 °C (78.6 °F).
On the coldest nights of the month, the temperature usually drops to around 11.5 °C (53 °F). However, it dropped to 9 °C (48.2 °F) in July 2002.
On the warmest days of the month, the temperature usually reaches around 36 °C (97 °F). However, it reached 41.5 °C (106.7 °F) in July 2020.
Precipitation amounts to 50 mm (2 in), distributed over 7 days.
The day lasts on average 15 hours and 0 minutes. So the days are long.
There are on average 6 hours of sunshine per day. So, the sun shines 40% of the time.
The average humidity is 74%. Hence, the air is normally humid.
The average wind speed is 9 kph (6 mph).
The average sea temperature is of 21 °C (69.5 °F). Therefore, the sea is cool for swimming.

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August, the warmest month of the year, is generally a warm month. The average temperature is of 21.6 °C (71 °F), with a minimum of 16.4 °C (61.4 °F) and a maximum of 26.9 °C (80.4 °F).
On the coldest nights of the month, the temperature usually drops to around 11.5 °C (53 °F). However, it dropped to 8.8 °C (47.8 °F) in August 1998.
On the warmest days of the month, the temperature usually reaches around 36.5 °C (97.5 °F). However, it reached 42 °C (107.6 °F) in August 2003.
Precipitation amounts to 75 mm (3 in), distributed over 8 days.
The day lasts on average 13 hours and 55 minutes.
There are on average 6 hours of sunshine per day. So, the sun shines 41% of the time.
The average humidity is 73%. Hence, the air is normally humid.
The average wind speed is 8 kph (5 mph).
The average sea temperature is of 21.5 °C (71 °F). Therefore, the sea is cool for swimming.

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September is generally a warm month. The average temperature is of 19.6 °C (67 °F), with a minimum of 14.1 °C (57.4 °F) and a maximum of 25 °C (77.1 °F).
On the coldest nights, which normally occur at the end of the month, the temperature usually drops to around 9 °C (48 °F). However, it dropped to 5.1 °C (41.2 °F) in September 2002.
On the warmest days, which normally occur at the beginning of the month, the temperature usually reaches around 34.5 °C (93.5 °F). However, it reached 40 °C (104 °F) in September 2016.
Precipitation amounts to 75 mm (3 in), distributed over 8 days.
The day lasts on average 12 hours and 25 minutes.
There are on average 5.5 hours of sunshine per day. So, the sun shines 43% of the time.
The average humidity is 73%. Hence, the air is normally humid.
The average wind speed is 8 kph (5 mph).
The average sea temperature is of 20.5 °C (69 °F). Therefore, the sea is cool for swimming.

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October is generally a very mild month. The average temperature is of 16.8 °C (62 °F), with a minimum of 11.8 °C (53.2 °F) and a maximum of 21.8 °C (71.3 °F).
On the coldest nights, which normally occur at the end of the month, the temperature usually drops to around 4.5 °C (40.5 °F). However, it dropped to 1 °C (33.8 °F) in October 2003.
On the warmest days, which normally occur at the beginning of the month, the temperature usually reaches around 29.5 °C (85 °F). However, it reached 34 °C (93.2 °F) in October 2001.
Precipitation amounts to 110 mm (4.3 in), distributed over 11 days.
The day lasts on average 11 hours and 0 minutes.
There are on average 4 hours of sunshine per day. So, the sun shines 37% of the time.
The average humidity is 72%. Hence, the air is normally humid.
The average wind speed is 9 kph (6 mph).
The average sea temperature is of 18 °C (64.5 °F). Therefore, the sea is cold for swimming.

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November is generally a mild month. The average temperature is of 12.5 °C (55 °F), with a minimum of 8.3 °C (47 °F) and a maximum of 16.7 °C (62.1 °F).
On the coldest nights, which normally occur at the end of the month, the temperature usually drops to around 1.5 °C (35 °F). However, it dropped to -4 °C (24.8 °F) in November 2007.
On the warmest days, which normally occur at the beginning of the month, the temperature usually reaches around 24 °C (75.5 °F). However, it reached 28 °C (82.4 °F) in November 2015.
Precipitation amounts to 145 mm (5.7 in), distributed over 13 days.
The day lasts on average 9 hours and 40 minutes.
There are on average 3 hours of sunshine per day. So, the sun shines 30% of the time.
The average humidity is 75%. Hence, the air is normally humid.
The average wind speed is 10 kph (6 mph).
The average sea temperature is of 15.5 °C (60 °F). Therefore, the sea is cold for swimming.

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December is generally a mild month. The average temperature is of 10.2 °C (50 °F), with a minimum of 6.1 °C (43 °F) and a maximum of 14.3 °C (57.7 °F).
On the coldest nights of the month, the temperature usually drops to around -0.5 °C (30.5 °F). However, it dropped to -6 °C (21.2 °F) in December 2001.
On the warmest days of the month, the temperature usually reaches around 21 °C (69.5 °F). However, it reached 25 °C (77 °F) in December 2000.
Precipitation amounts to 120 mm (4.7 in), distributed over 12 days.
The day lasts on average 9 hours and 0 minutes. December 21, the winter solstice, is the shortest day of the year in the Northern Hemisphere.
There are on average 2.5 hours of sunshine per day. So, the sun shines 28% of the time.
The average humidity is 74%. Hence, the air is normally humid.
The average wind speed is 10 kph (6 mph).
The average sea temperature is of 14 °C (57 °F). Therefore, the sea is very cold for swimming.