Climate - Honolulu (Hawaii)

The climate of Honolulu is tropical, with a hot season from June to October and a relatively cool season from December to March.
The city is the capital of Hawaii and is located on the southern side of the island of O'ahu, south of the Tropic of Cancer and in the middle of the Pacific Ocean.
The northeast trade winds blow from the mountains, slightly raising the temperature and reducing the humidity. Therefore, the rains are much less abundant than on the windward side, where the cities of Kaneohe and Kailua are located.
The average temperature of the coldest month (January) is of 23.1 °C (74 °F), that of the warmest month (August) is of 27.9 °C (82 °F). Here are the average temperatures.

Precipitation amounts to 415 millimeters (16.4 inches) per year: it is therefore quite scarce. It ranges from 15 mm (0.6 in) in the driest months (June, July) to 60 mm (2.4 in) in the wettest (March). However, the amount varies according to district: for instance, in Pearl Harbor, the rainfall amounts to 550 mm (21.5 in) per year, and at Black Point, it reaches 690 mm (27 in), while at the university, located near the green hills overlooking the city, it reaches 1,000 mm (40 in) per year, with more abundant rains from November to March, and some extra showers also in summer. Here is the average precipitation at the international airport.

From October to March, weather disturbances from the west can pass, bringing more abundant rains.
Sometimes, from November to April, cool air masses can also arrive, which can bring the minimum temperatures below 15 °C (59 °F), although these events are becoming rarer due to global warming. The record is 11 °C (52 °F), recorded in January 1969. Even in these cases, however, the temperature during the day generally reaches or exceeds 25 °C (77 °F).
On the hottest days of the year, which generally occur in August or September, the temperature reaches 32/33 °C (90/91 °F). The record is 35 °C (95 °F), set in September 1994 and in August 2019.
June to November, with a maximum from August to October, is hurricane season, although Hawaii is rarely affected. The last hurricane to hit Honolulu was Iniki in September 1992.



On average, there are around 3,035 sunshine hours per year. Therefore, the sun shines very often. Here are the average sunshine hours per day.

The sea temperature ranges between 24 °C (75 °F) and 27 °C (80 °F). It is therefore high enough for swimming all year round. Here are the average sea temperatures.

Best Time

In general, Honolulu can be visited all year round, however, you can choose the month of April, which is not as hot as the summer nor as rainy as the winter.
The period from June to September is sunny, with short showers, but it is also a bit muggy, even though the heat is generally not excessive thanks to the trade winds, and in any case you can go to the sea. In July and August there are many tourists.
From November to March, the temperatures are pleasant and there are many sunny days, although there can be periods of bad weather, with rain and wind, therefore this can be considered as the least advisable period.

Honolulu - Weather by month

Based on the period 1991-2020

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In January, the coolest month of the year, the weather in Honolulu is usually warm to hot and muggy. The average temperature is of 23.1 °C (74 °F), with a minimum of 19.3 °C (66.8 °F) and a maximum of 26.9 °C (80.5 °F).
On the coldest nights of the month, the temperature usually drops to around 15.5 °C (60 °F). However, it dropped to 11.7 °C (53.1 °F) in January 1998.
On the warmest days of the month, the temperature usually reaches around 29 °C (84 °F). However, it reached 31.1 °C (88 °F) in January 1996.
Precipitation amounts to 45 mm (1.8 in), distributed over 8 days.
The day lasts on average 11 hours and 0 minutes.
There are on average 7 hours of sunshine per day. So, the sun shines 63% of the time.
The average humidity is 71%. Hence, the air is normally humid.
The average wind speed is 14 kph (8 mph).
The average sea temperature is of 24.5 °C (76 °F). Therefore, the sea is warm enough for swimming.

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In February, the weather in Honolulu is usually warm to hot. The average temperature is of 23.2 °C (74 °F), with a minimum of 19.5 °C (67.1 °F) and a maximum of 26.9 °C (80.5 °F).
On the coldest nights of the month, the temperature usually drops to around 15.5 °C (60 °F). However, it dropped to 12.2 °C (54 °F) in February 1993.
On the warmest days of the month, the temperature usually reaches around 29 °C (84.5 °F). However, it reached 30.6 °C (87.1 °F) in February 1996.
Precipitation amounts to 50 mm (2 in), distributed over 8 days.
The day lasts on average 11 hours and 30 minutes.
There are on average 7.5 hours of sunshine per day. So, the sun shines 65% of the time.
The average humidity is 68%.
The average wind speed is 15 kph (9 mph).
The average sea temperature is of 24 °C (75.5 °F). Therefore, the sea is warm enough for swimming.

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In March, the weather in Honolulu is usually warm to hot. The average temperature is of 23.7 °C (75 °F), with a minimum of 20.1 °C (68.1 °F) and a maximum of 27.3 °C (81.2 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around 16.5 °C (62 °F). However, it dropped to 13.3 °C (55.9 °F) in March 1993.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 29.5 °C (85.5 °F). However, it reached 32.2 °C (90 °F) in March 2014.
Precipitation amounts to 60 mm (2.4 in), distributed over 9 days.
The day lasts on average 12 hours and 5 minutes.
There are on average 8.5 hours of sunshine per day. So, the sun shines 69% of the time.
The average humidity is 68%.
The average wind speed is 16 kph (10 mph).
The average sea temperature is of 24 °C (75.5 °F). Therefore, the sea is warm enough for swimming.

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In April, the weather in Honolulu is usually warm to hot. The average temperature is of 24.8 °C (77 °F), with a minimum of 21.2 °C (70.1 °F) and a maximum of 28.4 °C (83.1 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around 18 °C (64.5 °F). However, it dropped to 16.1 °C (61 °F) in April 2013.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 30 °C (86 °F). However, it reached 32.8 °C (91 °F) in April 1996.
Precipitation amounts to 20 mm (0.8 in), distributed over 8 days.
The day lasts on average 12 hours and 40 minutes.
There are on average 8.5 hours of sunshine per day. So, the sun shines 66% of the time.
The average humidity is 66%.
The average wind speed is 18 kph (11 mph).
The average sea temperature is of 24.5 °C (75.5 °F). Therefore, the sea is warm enough for swimming.

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In May, the weather in Honolulu is usually warm to hot. The average temperature is of 25.6 °C (78 °F), with a minimum of 21.9 °C (71.5 °F) and a maximum of 29.3 °C (84.8 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around 19 °C (66 °F). However, it dropped to 16.6 °C (61.9 °F) in May 1995.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 31.5 °C (88.5 °F). However, it reached 33.3 °C (91.9 °F) in May 1992.
Precipitation amounts to 20 mm (0.8 in), distributed over 6 days.
The day lasts on average 13 hours and 10 minutes.
There are on average 9 hours of sunshine per day. So, the sun shines 69% of the time.
The average humidity is 65%.
The average wind speed is 17 kph (10 mph).
The average sea temperature is of 25 °C (77 °F). Therefore, the sea is warm enough for swimming.

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In June, the weather in Honolulu is usually warm to hot. The average temperature is of 26.9 °C (80 °F), with a minimum of 23.2 °C (73.8 °F) and a maximum of 30.5 °C (86.9 °F).
On the coldest nights, the temperature usually drops to around 21 °C (70 °F). However, it dropped to 19.4 °C (66.9 °F) in June 1999.
On the warmest days, the temperature usually reaches around 32 °C (89 °F). However, it reached 33.3 °C (91.9 °F) in June 1992.
Precipitation amounts to 15 mm (0.6 in), distributed over 6 days.
The day lasts on average 13 hours and 25 minutes. June 21, the summer solstice, is the longest day of the year in the Northern Hemisphere.
There are on average 9.5 hours of sunshine per day. So, the sun shines 71% of the time.
The average humidity is 63%.
The average wind speed is 19 kph (12 mph).
The average sea temperature is of 25.5 °C (78 °F). Therefore, the sea is warm enough for swimming.

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In July, the weather in Honolulu is usually very hot. The average temperature is of 27.6 °C (82 °F), with a minimum of 23.9 °C (75.1 °F) and a maximum of 31.2 °C (88.1 °F).
On the coldest nights of the month, the temperature usually drops to around 22 °C (71.5 °F). However, it dropped to 20.6 °C (69.1 °F) in July 2010.
On the warmest days of the month, the temperature usually reaches around 32.5 °C (90.5 °F). However, it reached 34.4 °C (93.9 °F) in July 1995.
Precipitation amounts to 15 mm (0.6 in), distributed over 7 days.
The day lasts on average 13 hours and 20 minutes.
There are on average 10 hours of sunshine per day. So, the sun shines 74% of the time.
The average humidity is 64%.
The average wind speed is 19 kph (12 mph).
The average sea temperature is of 26 °C (79 °F). Therefore, the sea is warm enough for swimming.

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In August, the hottest month of the year, the weather in Honolulu is usually very hot. The average temperature is of 27.9 °C (82 °F), with a minimum of 24.2 °C (75.6 °F) and a maximum of 31.6 °C (88.8 °F).
On the coldest nights of the month, the temperature usually drops to around 22 °C (72 °F). However, it dropped to 18.3 °C (64.9 °F) in August 2009.
On the warmest days of the month, the temperature usually reaches around 33 °C (91 °F). However, it reached 35 °C (95 °F) in August 2019.
Precipitation amounts to 20 mm (0.8 in), distributed over 6 days.
The day lasts on average 12 hours and 50 minutes.
There are on average 10 hours of sunshine per day. So, the sun shines 76% of the time.
The average humidity is 63%.
The average wind speed is 19 kph (12 mph).
The average sea temperature is of 26.5 °C (79.5 °F). Therefore, the sea is pleasantly warm and allows long swims.

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In September, the weather in Honolulu is usually very hot. The average temperature is of 27.6 °C (82 °F), with a minimum of 23.8 °C (74.8 °F) and a maximum of 31.3 °C (88.4 °F).
On the coldest nights, the temperature usually drops to around 21.5 °C (70.5 °F). However, it dropped to 17.8 °C (64 °F) in September 2019.
On the warmest days, the temperature usually reaches around 33 °C (91 °F). However, it reached 35 °C (95 °F) in September 1994.
Precipitation amounts to 20 mm (0.8 in), distributed over 7 days.
The day lasts on average 12 hours and 10 minutes.
There are on average 9.5 hours of sunshine per day. So, the sun shines 76% of the time.
The average humidity is 66%.
The average wind speed is 17 kph (10 mph).
The average sea temperature is of 27 °C (80 °F). Therefore, the sea is pleasantly warm and allows long swims.

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In October, the weather in Honolulu is usually warm to hot. The average temperature is of 26.9 °C (80 °F), with a minimum of 23.3 °C (73.9 °F) and a maximum of 30.5 °C (86.9 °F).
On the coldest nights, which normally occur at the end of the month, the temperature usually drops to around 20.5 °C (68.5 °F). However, it dropped to 16.1 °C (61 °F) in October 1993.
On the warmest days, which normally occur at the beginning of the month, the temperature usually reaches around 32 °C (90 °F). However, it reached 33.9 °C (93 °F) in October 1993.
Precipitation amounts to 40 mm (1.6 in), distributed over 8 days.
The day lasts on average 11 hours and 35 minutes.
There are on average 8 hours of sunshine per day. So, the sun shines 68% of the time.
The average humidity is 68%.
The average wind speed is 16 kph (10 mph).
The average sea temperature is of 26.5 °C (80 °F). Therefore, the sea is pleasantly warm and allows long swims.

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In November, the weather in Honolulu is usually warm to hot. The average temperature is of 25.5 °C (78 °F), with a minimum of 22.1 °C (71.8 °F) and a maximum of 28.9 °C (84.1 °F).
On the coldest nights, which normally occur at the end of the month, the temperature usually drops to around 19 °C (66 °F). However, it dropped to 16.1 °C (61 °F) in November 1992.
On the warmest days, which normally occur at the beginning of the month, the temperature usually reaches around 30.5 °C (87 °F). However, it reached 32.8 °C (91 °F) in November 1995.
Precipitation amounts to 55 mm (2.2 in), distributed over 9 days.
The day lasts on average 11 hours and 5 minutes.
There are on average 6.5 hours of sunshine per day. So, the sun shines 60% of the time.
The average humidity is 69%.
The average wind speed is 16 kph (10 mph).
The average sea temperature is of 26 °C (79 °F). Therefore, the sea is warm enough for swimming.

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In December, the weather in Honolulu is usually warm to hot and muggy. The average temperature is of 24.2 °C (76 °F), with a minimum of 20.7 °C (69.2 °F) and a maximum of 27.7 °C (81.8 °F).
On the coldest nights of the month, the temperature usually drops to around 17.5 °C (63 °F). However, it dropped to 13.3 °C (55.9 °F) in December 1996.
On the warmest days of the month, the temperature usually reaches around 29.5 °C (84.5 °F). However, it reached 31.7 °C (89.1 °F) in December 1995.
Precipitation amounts to 55 mm (2.2 in), distributed over 9 days.
The day lasts on average 10 hours and 55 minutes. December 21, the winter solstice, is the shortest day of the year in the Northern Hemisphere.
There are on average 6.5 hours of sunshine per day. So, the sun shines 59% of the time.
The average humidity is 70%. Hence, the air is normally humid.
The average wind speed is 15 kph (9 mph).
The average sea temperature is of 25 °C (77 °F). Therefore, the sea is warm enough for swimming.