December weather forecastWaipahu, HI
December
Weather in December
Wrapping up the year, December brings with it a further decrease in temperatures, with the highest reading being 76.5°F (24.7°C) in Waipahu, Hawaii. As the city steps into the cooler months of the year, an increase in rainfall occurs. Despite this, December remains an attractive month for visitors thanks to the mild weather and ample daylight. Interestingly, the wind speed decreases slightly compared to November, with top gusts reaching 12.6mph (20.3km/h), providing a perfect cooling effect. The sea temperatures continue to remain inviting for water activities, rounding off the end-of-year festivities on a high note.Temperature
The transition into December is marked with an average high-temperature of a still moderately hot 76.5°F (24.7°C), showing an insignificant shift from November's 79°F (26.1°C). Waipahu registers an average low-temperature of 70.5°F (21.4°C) throughout December, a modest decrease from its daytime highs.Humidity
February and December, with an average relative humidity of 76%, are the most humid months.Rainfall
In Waipahu, Hawaii, in December, it is raining for 17 days, with typically 1.65" (42mm) of accumulated precipitation. In Waipahu, during the entire year, the rain falls for 208.4 days and collects up to 16.5" (419mm) of precipitation.Ocean temperature
In Waipahu, in December, the average water temperature is 77.4°F (25.2°C).Note: Water activities in surface temperatures between 77°F (25°C) and 84.2°F (29°C) are seen as exceptional and extremely agreeable for lengthened time spans.
Daylight
The month with the shortest days is December, with an average of 10h and 54min of daylight.On the first day of December, sunrise is at 6:53 am and sunset at 5:49 pm. On the last day of the month, sunrise is at 7:09 am and sunset at 6:01 pm HST.
Sunshine
The months with the least sunshine are November and December, with an average of 6.3h of sunshine.UV index
The months with the lowest UV index are January through August, October through December, with an average maximum UV index of 6. A UV Index of 6 to 7 symbolizes a high threat to health from exposure to the Sun's UV rays for ordinary individuals.Note: The daily maximum UV index of 6 in December interprets into the following advice:
Take precautions against overexposure. Fair-skinned people may get burned in less than 20 minutes. Seek shade and limit direct Sun exposure between 10 a.m. and 4 p.m., when UV radiation is at its peak, but be aware that not all shade structures provide complete sun protection. On days when the sun blazes, arm yourself with sunglasses that block UVA and UVB radiation. Notice! The reflection of water and sand increases the UV radiation significantly.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Waipahu, HI
- Average high temperature in December: 76.5°F
The warmest months (with the highest average high temperature) are August and September (82°F).
The months with the lowest average high temperature are February and March (75.4°F).
- Average low temperature in December: 70.5°F
The month with the highest average low temperature is September (75°F).
The coldest month (with the lowest average low temperature) is February (68°F).
Average pressure in December
Waipahu, HI
- Average pressure in December: 30"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 December
Waipahu, HI
- Average wind speed in December: 9.1mph
The windiest month (with the highest average wind speed) is July (11.3mph).
The calmest month (with the lowest average wind speed) is January (8.4mph).
Average humidity in December
Waipahu, HI
- Average humidity in December: 76%
The months with the highest relative humidity are February and December (76%).
The months with the lowest relative humidity are April, May, June and September (74%).
Average rainfall in December
Waipahu, HI
- Average rainfall in December: 1.65"
The wettest month (with the highest rainfall) is October (2.09").
The driest month (with the least rainfall) is July (0.71").
Average rainfall days in December
Waipahu, HI
- Average rainfall days in December: 17 days
The month with the highest number of rainy days is March (20 days).
The month with the least rainy days is January (13.5 days).
Average sea temperature in December
Waipahu, HI
- Average sea temperature in December: 77.3°F
The best month for swimming (with the highest average sea temperature) is September (80.6°F).
The coldest month (with the lowest average sea temperature) is March (75.7°F).
Average daylight in December /
Average sunshine in December
Waipahu, HI
- Average daylight in December: 10h and 54min
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 December: 6h and 18min
The month with the most sunshine is June (Average sunshine: 9h and 54min).
The months with the least sunshine are November and December (Average sunshine: 6h and 18min).
Average sunshine days in December
Waipahu, HI
- Average sunshine days in December: 9.2 days
The month with the most sunshine days is January (12.3 days).
The month with the least sunshine days is November (6.2 days).
Average UV index in December
Waipahu, HI
- Average UV index in December: 6
The month with the highest UV index is September (UV index 7).
The months with the lowest UV index are January, February, March, April, May, June, July, August, October, November and December (UV index 6).
Average cloud cover in December
Waipahu, HI
- Average cloud cover in December: 40
The month with the most cloud cover is March (Cloud cover 44).
The month with the least cloud cover is January (Cloud cover 36).
Average visibility in December
Waipahu, HI
- Average visibility in December: 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).
