Climate - Olympia (Washington_state)

The climate of Olympia is sub-oceanic, with quite cold, rainy winters and mild, fairly sunny summers.
The city is the capital of Washington State and is located in the southernmost part of the Puget Sound (the one where the mitigating influence of the sea is lowest), and approximately 75 km (45 mi) southwest of Seattle. About 85 km (50 mi) east-southeast we find Mount Rainier.
Fog can form at night, especially from October to March.
Although the winter is not very cold, every winter there can be a cold period, with night lows of -7/-8 °C (18/19 °F). Moreover, there can sometimes be cold waves, sometimes even in November, with lows going down to -10 °C (14 °F) or even below. The temperature dropped to -22.3 °C (-8 °F) in January 1979, to -18.3 (-0.9 °F) and in December 1998, to -17.8 °C (0 °F) in November 1985, and to -17.2 °C (1 °F) in December 1990.
Snow is quite rare, but given the high precipitation level, a heavy snowfall can occasionally occur. On average, 10 cm (4 in) of snow fall per year.
In summer, nights are cool, and sometimes even a little cold, while the days are generally pleasant. However, it can sometimes get hot, and on the hottest days of the year, it can reach 35/36 °C (95/97 °F). In August 1981 and in July 2009, the temperature reached 40 °C (104 °F), while during the heat wave of late June 2021, it reached 43 °C (109 °F).
The average temperature of the coldest month (December) is of 3.8 °C (38.9 °F), that of the warmest months (July, August) is of 17.9 °C (64.2 °F). Here are the average temperatures.

Precipitation amounts to 1,285 millimeters (50.6 inches) per year: it is therefore quite abundant. The city is rainier than Seattle because it is located more to the south and therefore is not protected by the Olympic Mountains. However, here too, the high pressure system prevails in summer, which brings good weather. Precipitation ranges from 15 mm (0.6 in) in the driest month (July) to 210 mm (8.3 in) in the wettest (November). Here is the average precipitation.

The sea temperature ranges between 8 °C (46 °F) and 13.5 °C (56 °F). So, it is cold all year round. Here are the average sea temperatures.

Best Time

The best time to visit Olympia is summer, especially in July and August, since it is the mildest, driest and sunniest period of the year. May, June and September are also acceptable months.

Back to the climate of Washington state.

Olympia - Weather by month

Based on the period 1991-2020

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In January, the weather in Olympia is usually quite cold. The average temperature is of 4.2 °C (40 °F), with a minimum of 0.7 °C (33.2 °F) and a maximum of 7.8 °C (46 °F).
On the coldest nights of the month, the temperature usually drops to around -7.5 °C (19 °F). However, it dropped to -12.3 °C (9.9 °F) in January 1993.
On the warmest days of the month, the temperature usually reaches around 13.5 °C (56 °F). However, it reached 17.8 °C (64 °F) in January 2005.
Precipitation amounts to 200 mm (7.9 in), distributed over 20 days.
The day lasts on average 9 hours and 0 minutes.
The average humidity is 89%. Hence, the air is normally humid.
The average wind speed is 9 kph (6 mph).
The average sea temperature is of 8 °C (46.5 °F). Therefore, the sea is very cold for swimming.

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In February, the weather in Olympia is usually quite cold. The average temperature is of 4.8 °C (41 °F), with a minimum of 0.2 °C (32.3 °F) and a maximum of 9.5 °C (49.1 °F).
On the coldest nights of the month, the temperature usually drops to around -7 °C (19 °F). However, it dropped to -15 °C (5 °F) in February 2011.
On the warmest days of the month, the temperature usually reaches around 15 °C (59.5 °F). However, it reached 21.7 °C (71.1 °F) in February 1992.
Precipitation amounts to 130 mm (5.1 in), distributed over 16 days.
The day lasts on average 10 hours and 25 minutes.
The average humidity is 83%. Hence, the air is normally humid.
The average wind speed is 9 kph (6 mph).
The average sea temperature is of 8 °C (46.5 °F). Therefore, the sea is very cold for swimming.

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In March, the weather in Olympia is usually quite mild. The average temperature is of 6.7 °C (44 °F), with a minimum of 1.4 °C (34.5 °F) and a maximum of 12.1 °C (53.7 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around -4.5 °C (23.5 °F). However, it dropped to -10 °C (14 °F) in March 1991.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 20 °C (68 °F). However, it reached 26.1 °C (79 °F) in March 2004.
Precipitation amounts to 145 mm (5.7 in), distributed over 19 days.
The day lasts on average 12 hours and 0 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 8.5 °C (47 °F). Therefore, the sea is very cold for swimming.

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In April, the weather in Olympia is usually mild. The average temperature is of 9 °C (48 °F), with a minimum of 3.1 °C (37.5 °F) and a maximum of 14.9 °C (58.9 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around -2.5 °C (27.5 °F). However, it dropped to -5 °C (23 °F) in April 2020.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 24.5 °C (76 °F). However, it reached 31.1 °C (88 °F) in April 2016.
Precipitation amounts to 95 mm (3.7 in), distributed over 16 days.
The day lasts on average 13 hours and 40 minutes.
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 9 °C (48.5 °F). Therefore, the sea is very cold for swimming.

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In May, the weather in Olympia is usually mild. The average temperature is of 12.5 °C (55 °F), with a minimum of 6.1 °C (43 °F) and a maximum of 18.9 °C (66.1 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around 0.5 °C (32.5 °F). However, it dropped to -3 °C (26.6 °F) in May 2002.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 29 °C (84.5 °F). However, it reached 33.3 °C (91.9 °F) in May 2005.
Precipitation amounts to 55 mm (2.2 in), distributed over 11 days.
The day lasts on average 15 hours and 5 minutes. So the days are long.
The average humidity is 70%.
The average wind speed is 9 kph (6 mph).
The average sea temperature is of 10.5 °C (51 °F). Therefore, the sea is very cold for swimming.

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In June, the weather in Olympia is usually very mild. However, there are remarkable differences between night and day. The average temperature is of 15.1 °C (59 °F), with a minimum of 8.6 °C (47.4 °F) and a maximum of 21.6 °C (70.8 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around 3.5 °C (38.5 °F). However, it dropped to 0.6 °C (33.1 °F) in June 1991.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 31 °C (88 °F). However, it reached 36.7 °C (98.1 °F) in June 2017.
Precipitation amounts to 35 mm (1.4 in), distributed over 8 days.
The day lasts on average 15 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 69%.
The average wind speed is 9 kph (6 mph).
The average sea temperature is of 12 °C (53.5 °F). Therefore, the sea is very cold for swimming.

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In July, the weather in Olympia is usually very mild. However, there are remarkable differences between night and day. The average temperature is of 17.9 °C (64 °F), with a minimum of 10.4 °C (50.7 °F) and a maximum of 25.3 °C (77.6 °F).
On the coldest nights of the month, the temperature usually drops to around 6 °C (43 °F). However, it dropped to 3.3 °C (37.9 °F) in July 2003.
On the warmest days of the month, the temperature usually reaches around 34 °C (93.5 °F). However, it reached 40 °C (104 °F) in July 2009.
Precipitation amounts to 15 mm (0.6 in), distributed over 4 days.
The day lasts on average 15 hours and 25 minutes. So the days are long.
The average humidity is 66%.
The average wind speed is 9 kph (5 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 Olympia is usually very mild. However, there are remarkable differences between night and day. The average temperature is of 17.9 °C (64 °F), with a minimum of 10.3 °C (50.5 °F) and a maximum of 25.6 °C (78 °F).
On the coldest nights of the month, the temperature usually drops to around 5.5 °C (42 °F). However, it dropped to 3.3 °C (37.9 °F) in August 2003.
On the warmest days of the month, the temperature usually reaches around 33.5 °C (92 °F). However, it reached 37.2 °C (99 °F) in August 2020.
Precipitation amounts to 25 mm (1 in), distributed over 5 days.
The day lasts on average 14 hours and 5 minutes. So the days are long.
The average humidity is 67%.
The average wind speed is 8 kph (5 mph).
The average sea temperature is of 13.5 °C (56 °F). Therefore, the sea is very cold for swimming.

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In September, the weather in Olympia is usually very mild. However, there are remarkable differences between night and day. The average temperature is of 15.1 °C (59 °F), with a minimum of 7.9 °C (46.2 °F) and a maximum of 22.3 °C (72.1 °F).
On the coldest nights, which normally occur at the end of the month, the temperature usually drops to around 2 °C (36 °F). However, it dropped to -3.3 °C (26.1 °F) in September 2000.
On the warmest days, which normally occur at the beginning of the month, the temperature usually reaches around 30.5 °C (86.5 °F). However, it reached 33.3 °C (91.9 °F) in September 2003.
Precipitation amounts to 50 mm (2 in), distributed over 8 days.
The day lasts on average 12 hours and 30 minutes.
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 13 °C (55 °F). Therefore, the sea is very cold for swimming.

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In October, the weather in Olympia is usually mild. The average temperature is of 10.2 °C (50 °F), with a minimum of 4.7 °C (40.5 °F) and a maximum of 15.7 °C (60.2 °F).
On the coldest nights, which normally occur at the end of the month, the temperature usually drops to around -2 °C (28 °F). However, it dropped to -8.3 °C (17.1 °F) in October 2002.
On the warmest days, which normally occur at the beginning of the month, the temperature usually reaches around 23.5 °C (74 °F). However, it reached 30 °C (86 °F) in October 1991.
Precipitation amounts to 130 mm (5.1 in), distributed over 15 days.
The day lasts on average 10 hours and 50 minutes.
The average humidity is 83%. Hence, the air is normally humid.
The average wind speed is 8 kph (5 mph).
The average sea temperature is of 11 °C (52 °F). Therefore, the sea is very cold for swimming.

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In November, the weather in Olympia is usually quite cold. The average temperature is of 6.2 °C (43 °F), with a minimum of 2.1 °C (35.8 °F) and a maximum of 10.3 °C (50.6 °F).
On the coldest nights, which normally occur at the end of the month, the temperature usually drops to around -6 °C (21.5 °F). However, it dropped to -12.8 °C (9 °F) in November 2010.
On the warmest days, which normally occur at the beginning of the month, the temperature usually reaches around 16.5 °C (62 °F). However, it reached 22.8 °C (73 °F) in November 2002.
Precipitation amounts to 210 mm (8.3 in), distributed over 20 days.
The day lasts on average 9 hours and 20 minutes.
The average humidity is 88%. Hence, the air is normally humid.
The average wind speed is 10 kph (6 mph).
The average sea temperature is of 9.5 °C (49.5 °F). Therefore, the sea is very cold for swimming.

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In December, the coldest month of the year, the weather in Olympia is usually cold. The average temperature is of 3.8 °C (39 °F), with a minimum of 0.4 °C (32.8 °F) and a maximum of 7.2 °C (44.9 °F).
On the coldest nights of the month, the temperature usually drops to around -7.5 °C (18 °F). However, it dropped to -18.3 °C (-0.9 °F) in December 1998.
On the warmest days of the month, the temperature usually reaches around 13 °C (55.5 °F). However, it reached 17.8 °C (64 °F) in December 2014.
Precipitation amounts to 200 mm (7.9 in), distributed over 20 days.
The day lasts on average 8 hours and 35 minutes. December 21, the winter solstice, is the shortest day of the year in the Northern Hemisphere.
The average humidity is 89%. Hence, the air is normally humid.
The average wind speed is 9 kph (6 mph).
The average sea temperature is of 8.5 °C (47.5 °F). Therefore, the sea is very cold for swimming.