Climate - Concord (California)

The climate of Concord is Mediterranean, with mild, rainy winters and hot, sunny summers.
The city is located near the coast of Suisun Bay, a northern extension of San Francisco Bay. Nearby are cities such as Pleasant Hill, Pacheco, Walnut Creek, Clayton, Pittsburg, Bay Point and Clyde.
Winter, from December to February, is mild, with periods of bad weather alternating with sunny periods. In the latter, fog can form at night.
On average, there are 9 days on which the minimum temperature is equal to or below freezing, and that usually happens from November through February. However, the temperature generally drops slightly below freezing. In December 1990, it dropped to -5.5 °C (22 °F).
Summer, from June to September, is hot and sunny, with quite cool nights. There can be very hot periods, in which the wind blows from the desert, but even in these cases, the temperature generally drops below 20 °C (68 °F) during the night, thanks to the breeze coming from the bay.
On average, there are 9 days with a maximum temperature equal to or above 37.8 °C (100 °F), and that usually happens from June through September. In July 2006, it reached 44.4 °C (112 °F). However, short hot periods, in which the wind blows from the desert and the temperature exceeds 32 °C (90 °F), can also occur in April, May and October.
The average temperature of the coldest month (January) is of 9.7 °C (49 °F), that of the warmest month (August) is of 23.1 °C (74 °F). Here are the average temperatures.

Precipitation amounts to 410 millimeters (16.1 inches) per year: it is therefore quite scarce. It ranges from 0 mm (0 in) in the driest months (July, August, September) to 80 mm (3.1 in) in the wettest ones (January, February, December). Here is the average precipitation.




The sea temperature ranges between 12 °C (53 °F) and 14.5 °C (58 °F). So, it is cold all year round. Here are the average sea temperatures.

Best Time

The best times to visit Concord are spring and autumn, and in particular the months of April, May and October. It can get very hot at times, but less often than in summer.

Back to California.

Concord - Weather by month

Based on the period 1991-2020

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In January, the coldest month of the year, the weather in Concord is usually mild. The average temperature is of 9.7 °C (49 °F), with a minimum of 5.1 °C (41.2 °F) and a maximum of 14.2 °C (57.6 °F).
On the coldest nights of the month, the temperature usually drops to around 0 °C (32 °F).
On the warmest days of the month, the temperature usually reaches around 18.5 °C (65.5 °F).
Precipitation amounts to 80 mm (3.1 in), distributed over 9 days.
The day lasts on average 9 hours and 55 minutes.
The average humidity is 79%. Hence, the air is normally humid.
The average wind speed is 10 kph (6 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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In February, the weather in Concord is usually mild. The average temperature is of 11.6 °C (53 °F), with a minimum of 6.6 °C (43.8 °F) and a maximum of 16.7 °C (62.1 °F).
On the coldest nights of the month, the temperature usually drops to around 1.5 °C (34.5 °F).
On the warmest days of the month, the temperature usually reaches around 21.5 °C (71 °F).
Precipitation amounts to 80 mm (3.1 in), distributed over 9 days.
The day lasts on average 10 hours and 50 minutes.
The average humidity is 73%. Hence, the air is normally humid.
The average wind speed is 10 kph (6 mph).
The average sea temperature is of 12 °C (54 °F). Therefore, the sea is very cold for swimming.

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In March, the weather in Concord is usually mild. The average temperature is of 13.7 °C (57 °F), with a minimum of 8.1 °C (46.6 °F) and a maximum of 19.3 °C (66.7 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around 3 °C (37.5 °F).
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 25 °C (77.5 °F).
Precipitation amounts to 55 mm (2.2 in), distributed over 9 days.
The day lasts on average 12 hours and 0 minutes.
The average humidity is 64%.
The average wind speed is 12 kph (8 mph).
The average sea temperature is of 12 °C (54 °F). Therefore, the sea is very cold for swimming.

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In April, the weather in Concord is usually very mild. The average temperature is of 15.6 °C (60 °F), with a minimum of 9.5 °C (49.1 °F) and a maximum of 21.8 °C (71.2 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around 4 °C (39.5 °F).
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 29.5 °C (85.5 °F).
Precipitation amounts to 30 mm (1.2 in), distributed over 5 days.
The day lasts on average 13 hours and 10 minutes.
The average humidity is 58%.
The average wind speed is 15 kph (9 mph).
The average sea temperature is of 12 °C (53 °F). Therefore, the sea is very cold for swimming.

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In May, the weather in Concord is usually warm. However, there are remarkable differences between night and day. The average temperature is of 18.5 °C (65 °F), with a minimum of 11.7 °C (53 °F) and a maximum of 25.3 °C (77.5 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around 8.5 °C (47 °F).
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 34 °C (93 °F).
Precipitation amounts to 15 mm (0.6 in), distributed over 3 days.
The day lasts on average 14 hours and 20 minutes. So the days are long.
The average humidity is 54%.
The average wind speed is 16 kph (10 mph).
The average sea temperature is of 12 °C (53 °F). Therefore, the sea is very cold for swimming.

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In June, the weather in Concord is usually warm. However, there are remarkable differences between night and day. The average temperature is of 21.5 °C (71 °F), with a minimum of 13.9 °C (57.1 °F) and a maximum of 29 °C (84.2 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around 11 °C (51.5 °F).
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 38.5 °C (101 °F).
Precipitation amounts to only 5 mm (0.2 in), and all occurs in one day.
The day lasts on average 14 hours and 50 minutes. So the days are long. June 21, the summer solstice, is the longest day of the year in the Northern Hemisphere.
The average humidity is 50%.
The average wind speed is 18 kph (11 mph).
The average sea temperature is of 12 °C (54 °F). Therefore, the sea is very cold for swimming.

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In July, the weather in Concord is usually warm to hot. However, there are remarkable differences between night and day. The average temperature is of 23.0 °C (73 °F), with a minimum of 14.8 °C (58.7 °F) and a maximum of 31.1 °C (88 °F).
On the coldest nights of the month, the temperature usually drops to around 12.5 °C (54.5 °F).
On the warmest days of the month, the temperature usually reaches around 39.5 °C (103 °F).
Precipitation amounts to only 0 mm (0 in), so on average it never rains in the whole month.
The day lasts on average 14 hours and 30 minutes. So the days are long.
The average humidity is 51%.
The average wind speed is 18 kph (11 mph).
The average sea temperature is of 13 °C (55.5 °F). Therefore, the sea is very cold for swimming.

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In August, the warmest month of the year, the weather in Concord is usually warm to hot. However, there are remarkable differences between night and day. The average temperature is of 23.1 °C (74 °F), with a minimum of 15.2 °C (59.4 °F) and a maximum of 31.1 °C (87.9 °F).
On the coldest nights of the month, the temperature usually drops to around 12.5 °C (54 °F).
On the warmest days of the month, the temperature usually reaches around 39 °C (102 °F).
Precipitation amounts to only 0 mm (0 in), so on average it never rains in the whole month.
The day lasts on average 13 hours and 30 minutes.
The average humidity is 51%.
The average wind speed is 16 kph (10 mph).
The average sea temperature is of 14 °C (57 °F). Therefore, the sea is very cold for swimming.

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In September, the weather in Concord is usually warm. However, there are remarkable differences between night and day. The average temperature is of 22.0 °C (72 °F), with a minimum of 14.3 °C (57.8 °F) and a maximum of 29.6 °C (85.3 °F).
On the coldest nights, which normally occur at the end of the month, the temperature usually drops to around 10.5 °C (50.5 °F).
On the warmest days, which normally occur at the beginning of the month, the temperature usually reaches around 37 °C (99 °F).
Precipitation amounts to only 0 mm (0 in), so on average it never rains in the whole month.
The day lasts on average 12 hours and 25 minutes.
The average humidity is 52%.
The average wind speed is 13 kph (8 mph).
The average sea temperature is of 14.5 °C (58 °F). Therefore, the sea is very cold for swimming.

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In October, the weather in Concord is usually warm. However, there are remarkable differences between night and day. The average temperature is of 18.5 °C (65 °F), with a minimum of 11.4 °C (52.6 °F) and a maximum of 25.6 °C (78.1 °F).
On the coldest nights, which normally occur at the end of the month, the temperature usually drops to around 6.5 °C (43.5 °F).
On the warmest days, which normally occur at the beginning of the month, the temperature usually reaches around 33 °C (91 °F).
Precipitation amounts to 20 mm (0.8 in), distributed over 3 days.
The day lasts on average 11 hours and 10 minutes.
The average humidity is 54%.
The average wind speed is 11 kph (7 mph).
The average sea temperature is of 14 °C (57.5 °F). Therefore, the sea is very cold for swimming.

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In November, the weather in Concord is usually mild. The average temperature is of 13.1 °C (56 °F), with a minimum of 7.3 °C (45.2 °F) and a maximum of 18.9 °C (66.1 °F).
On the coldest nights, which normally occur at the end of the month, the temperature usually drops to around 2 °C (35 °F).
On the warmest days, which normally occur at the beginning of the month, the temperature usually reaches around 25.5 °C (77.5 °F).
Precipitation amounts to 40 mm (1.6 in), distributed over 6 days.
The day lasts on average 10 hours and 5 minutes.
The average humidity is 67%.
The average wind speed is 9 kph (5 mph).
The average sea temperature is of 13.5 °C (56.5 °F). Therefore, the sea is very cold for swimming.

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In December, the weather in Concord is usually mild. The average temperature is of 9.7 °C (49 °F), with a minimum of 4.8 °C (40.7 °F) and a maximum of 14.6 °C (58.2 °F).
On the coldest nights of the month, the temperature usually drops to around -1 °C (30.5 °F).
On the warmest days of the month, the temperature usually reaches around 19 °C (66.5 °F).
Precipitation amounts to 80 mm (3.1 in), distributed over 10 days.
The day lasts on average 9 hours and 35 minutes. December 21, the winter solstice, is the shortest day of the year in the Northern Hemisphere.
The average humidity is 75%. Hence, the air is normally humid.
The average wind speed is 9 kph (6 mph).
The average sea temperature is of 12.5 °C (55 °F). Therefore, the sea is very cold for swimming.