Contents
- Weather in May
- Frequently asked questions
- Average temperature in May
- Average pressure in May
- Average wind speed in May
- Average humidity in May
- Average rainfall in May
- Average rainfall days in May
- Average sea temperature in May
- Average daylight in May
- Average sunshine in May
- Average sunshine days in May
- Average UV index in May
- Average cloud cover in May
- Average visibility in May
Weather in May
Temperature
Welcoming May, Hilo notes an average high-temperature of a still agreeable 72.1°F (22.3°C), nearly consistent with April's 70.9°F (21.6°C). In Hilo, May is characterized by an average low-temperature of 66.2°F (19°C), indicating a minor drop from daytime highs.Humidity
The months with the lowest humidity in Hilo are January, May through July, with an average relative humidity of 78%.Rainfall
In Hilo, in May, during 20.2 rainfall days, 1.38" (35mm) of precipitation is typically accumulated. Throughout the year, there are 227.7 rainfall days, and 27.83" (707mm) of precipitation is accumulated.Ocean temperature
In May, the average ocean temperature in Hilo is 76.8°F (24.9°C).Note: For someone not comfortable with cold, swimming in 76.8°F (24.9°C) waters might be a stretch. However, with favorable conditions like abundant sunshine, mild wind, and warm air temperatures, the experience can be improved. And while wetsuits are not a must, they can be considered.
Daylight
The average length of the day in May in Hilo, Hawaii, is 13h and 5min.On the first day of May, sunrise is at 5:50 am and sunset at 6:43 pm. On the last day of the month, sunrise is at 5:40 am and sunset at 6:55 pm HST.
Sunshine
The average sunshine in May in Hilo is 10.6h.UV index
The months with the highest UV index are May through December, with an average maximum UV index of 6. A UV Index reading of 6 to 7 represents a high health vulnerability from exposure to the Sun's UV rays for average individuals.Note: The daily maximum UV index of 6 in May interprets into the following advice:
Sustain precautions and conform to sun safety norms. Preventing sunburn is necessary. The Sun's UV radiation is most intense from 10 a.m. to 4 p.m. Try to avoid direct sun exposure during these hours. Limit sun-induced ocular harm with sunglasses that feature UVA and UVB filtration. Be mindful! Sand and water reflections can up the Sun's UV exposure.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What is the temperature in May in Hilo?
What are the least humid months in Hilo?
What is the average humidity in May in Hilo?
How much does it rain in Hilo in May?
How warm is the water in May in Hilo?
How many hours of daylight does Hilo have in May?
When are sunrise and sunset in May in Hilo?
How many hours of sunshine does Hilo have in May?
When is the highest UV index in Hilo?
What is the UV index reading in May in Hilo?
Average temperature in May
Hilo, HI
- Average high temperature in May: 72.1°F
The warmest month (with the highest average high temperature) is August (75.4°F).
The month with the lowest average high temperature is March (69.6°F).
- Average low temperature in May: 66.2°F
The month with the highest average low temperature is September (70°F).
The coldest month (with the lowest average low temperature) is March (64°F).
Average pressure in May
Hilo, HI
- Average pressure in May: 30.04"Hg
The month with the highest atmospheric pressure is April (30.05"Hg).
The months with the lowest atmospheric pressure are September and October (29.97"Hg).
Average wind speed in May
Hilo, HI
- Average wind speed in May: 7mph
The windiest month (with the highest average wind speed) is August (7.6mph).
The calmest month (with the lowest average wind speed) is October (6.7mph).
Average humidity in May
Hilo, HI
- Average humidity in May: 78%
The month with the highest relative humidity is March (80%).
The months with the lowest relative humidity are January, May, June and July (78%).
Average rainfall in May
Hilo, HI
- Average rainfall in May: 1.38"
The wettest month (with the highest rainfall) is February (3.78").
The driest month (with the least rainfall) is June (1.1").
Average rainfall days in May
Hilo, HI
- Average rainfall days in May: 20.2 days
The month with the highest number of rainy days is March (22.9 days).
The month with the least rainy days is January (13.3 days).
Average sea temperature in May
Hilo, HI
- Average sea temperature in May: 76.9°F
The best month for swimming (with the highest average sea temperature) is September (79.3°F).
The coldest month (with the lowest average sea temperature) is March (75.7°F).
Average daylight in May /
Average sunshine in May
Hilo, HI
- Average daylight in May: 13h and 1min
The month with the longest days is June (Average daylight: 13h and 18min).
The month with the shortest days is December (Average daylight: 11h and 0min).
- Average sunshine in May: 10h and 4min
The month with the most sunshine is June (Average sunshine: 10h and 54min).
The month with the least sunshine is December (Average sunshine: 6h and 30min).
Average sunshine days in May
Hilo, HI
- Average sunshine days in May: 3.3 days
The month with the most sunshine days is January (12.1 days).
The month with the least sunshine days is August (1.8 days).
Average UV index in May
Hilo, HI
- Average UV index in May: 6
The months with the highest UV index are May, June, July, August, September, October, November and December (UV index 6).
The months with the lowest UV index are January, February, March and April (UV index 5).
Average cloud cover in May
Hilo, HI
- Average cloud cover in May: 33
The month with the most cloud cover is March (Cloud cover 42).
The month with the least cloud cover is January (Cloud cover 26).
Average visibility in May
Hilo, 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).
Hilo, Hawaii, USA
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