May weather forecastHeeia, HI
May
Weather in May
May, the last month of the spring in Heeia, is also a moderately hot month, with an average temperature varying between 73.2°F (22.9°C) and 77.5°F (25.3°C).Temperature
May's weather records an average high-temperature of a still moderately hot 77.5°F (25.3°C), showing little deviation from April. In Heeia, the nighttime temperature in May descends gently to an average of 73.2°F (22.9°C).Humidity
The months with the lowest humidity are January, May, June, September and November, with an average relative humidity of 75%.Rainfall
In Heeia, in May, it is raining for 17.2 days, with typically 1.34" (34mm) of accumulated precipitation. Throughout the year, in Heeia, there are 187.1 rainfall days, and 15.83" (402mm) of precipitation is accumulated.Ocean temperature
In May, the average ocean temperature is 77.9°F (25.5°C).Note: For engaging in water activities including swimming and diving, temperatures from 77°F (25°C) to 84.2°F (29°C) are perceived as perfect, providing pleasure for extended durations.
Daylight
In May, the average length of the day is 13h and 10min.On the first day of May, sunrise is at 5:59 am and sunset at 6:56 pm. On the last day of the month, sunrise is at 5:48 am and sunset at 7:09 pm HST.
Sunshine
In May, the average sunshine is 10.3h.UV index
The months with the lowest UV index in Heeia are January through June, October through December, with an average maximum UV index of 6. A UV Index reading of 6 to 7 represents a high health risk from exposure to the Sun's UV rays for average individuals.Note: A maximum high daily UV index of 6 during May translates into the following directions:
Persist in precautions and follow sun safety policies. Keeping sunburn at bay is imperative. Avoid direct Sun exposure from 10 a.m. to 4 p.m., a period when UV radiation is most intense, and remember that not all shade structures provide full protection. To mitigate harm from sun exposure, pick sunglasses offering UVA and UVB defense. Be vigilant! The Sun's UV rays get a boost from sand and water reflections.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in May
Heeia, HI
- Average high temperature in May: 77.5°F
The warmest months (with the highest average high temperature) are August and September (81°F).
The month with the lowest average high temperature is February (74.3°F).
- Average low temperature in May: 73.2°F
The month with the highest average low temperature is August (76.6°F).
The coldest month (with the lowest average low temperature) is February (69.6°F).
Average pressure in May
Heeia, HI
- Average pressure in May: 30.04"Hg
The month with the highest atmospheric pressure is April (30.06"Hg).
The months with the lowest atmospheric pressure are September and October (29.97"Hg).
Average wind speed in May
Heeia, HI
- Average wind speed in May: 11.2mph
The windiest month (with the highest average wind speed) is July (13.5mph).
The calmest month (with the lowest average wind speed) is January (10.3mph).
Average humidity in May
Heeia, HI
- Average humidity in May: 75%
The months with the highest relative humidity are February, March, April, July, August, October and December (76%).
The months with the lowest relative humidity are January, May, June, September and November (75%).
Average rainfall in May
Heeia, HI
- Average rainfall in May: 1.34"
The wettest month (with the highest rainfall) is March (2.01").
The driest month (with the least rainfall) is July (0.71").
Average rainfall days in May
Heeia, HI
- Average rainfall days in May: 17.2 days
The month with the highest number of rainy days is March (18.3 days).
The month with the least rainy days is June (13.5 days).
Average sea temperature in May
Heeia, HI
- Average sea temperature in May: 78°F
The best month for swimming (with the highest average sea temperature) is September (80.4°F).
The coldest month (with the lowest average sea temperature) is March (75.7°F).
Average daylight in May /
Average sunshine in May
Heeia, HI
- Average daylight in May: 13h and 12min
The month with the longest days is June (Average daylight: 13h and 24min).
The month with the shortest days is December (Average daylight: 10h and 54min).
- Average sunshine in May: 10h and 18min
The month with the most sunshine is June (Average sunshine: 10h and 42min).
The month with the least sunshine is December (Average sunshine: 6h and 18min).
Average sunshine days in May
Heeia, HI
- Average sunshine days in May: 8.9 days
The month with the most sunshine days is June (12.2 days).
The month with the least sunshine days is April (6.5 days).
Average UV index in May
Heeia, HI
- Average UV index in May: 6
The months with the highest UV index are July, August and September (UV index 7).
The months with the lowest UV index are January, February, March, April, May, June, October, November and December (UV index 6).
Average cloud cover in May
Heeia, HI
- Average cloud cover in May: 35
The month with the most cloud cover is March (Cloud cover 41).
The month with the least cloud cover is September (Cloud cover 32).
Average visibility in May
Heeia, HI
- Average visibility in May: 6mi
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).





