December weather forecastGuayanilla, PR
December
Weather in December
As Guayanilla welcomes December, the weather remains warm yet comfortable. Light winds of 6.7mph (10.8km/h) bring a soothing touch to the city's predictable tropical weather. Signifying the end of the calendar year, December notes a decline in the city's temperature, recording a high of 82.4°F (28°C). The month also retains a steady flux of late year tourists, drawn by the city's historic charm and weather that's constantly warm. The clear skies, gentle sunlight, and minimal rainfall make December an ideal time to direct the lens towards the city's architectural magnificence or partake in a beachside retreat.Temperature
During December, Guayanilla records an average high-temperature of a still moderately hot 82.4°F (28°C), marking a slight divergence from November's 83.8°F (28.8°C). Throughout December, Guayanilla encounters an average temperature drop to a pleasant 73.2°F (22.9°C).Heat index
December's heat index is computed to be a tropical 89.6°F (32°C). If one stays active during extended exposure, it might induce fatigue and result in heat cramps.Evaluating the heat index requires understanding its values in the shade and with gentle winds. With direct sunlight, the heat index could increase by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'apparent temperature' or 'feels like', marries air temperature and humidity to produce a value illustrating perceived warmth. A person's impression of weather can be shaped by several aspects, among them metabolic variations, pregnancy, and levels of physical activity. Direct sunlight exposure should be noted as it has the potential to increase the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are particularly important for children. Youngsters often neglect the necessity for rest and hydration. Thirst is a sign of advancing dehydration - thus the importance of maintaining hydration, specifically during long-lasting physical activities.
Humidity
In December, the average relative humidity is 78%.Rainfall
In Guayanilla, in December, during 16.3 rainfall days, 1.22" (31mm) of precipitation is typically accumulated. In Guayanilla, during the entire year, the rain falls for 224.9 days and collects up to 23.58" (599mm) of precipitation.Snowfall
In Guayanilla, snow does not fall in January through August, October through December.Daylight
With an average of 11h and 6min of daylight, December has the shortest days of the year in Guayanilla.On the first day of the month, sunrise is at 6:42 am and sunset at 5:50 pm. On the last day of December, in Guayanilla, sunrise is at 6:58 am and sunset at 6:02 pm AST.
Sunshine
In December, the average sunshine is 7.4h.UV index
January through March, November and December, with an average maximum UV index of 6, are months with the lowest UV index. A UV Index of 6 to 7 symbolizes a high threat to health from unsafe exposure to UV radiation for the average person.Note: The maximum daily UV index of 6 during December translates into the following directions:
Take precautions against overexposure. Protection against sun damage is needed. Limit direct sun exposure especially between 10 a.m. and 4 p.m., when UV radiation is at its peak. However, keep in mind that shade structures may not provide full sun protection. Stay sun-safe with clothing that is both closely woven and worn loosely.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Guayanilla, PR
- Average high temperature in December: 82.4°F
The warmest month (with the highest average high temperature) is August (86.5°F).
The month with the lowest average high temperature is January (81.9°F).
- Average low temperature in December: 73.2°F
The months with the highest average low temperature are July, August and October (76.6°F).
The coldest month (with the lowest average low temperature) is March (71.4°F).
Average pressure in December
Guayanilla, PR
- Average pressure in December: 29.97"Hg
The months with the highest atmospheric pressure are January and February (30.01"Hg).
The month with the lowest atmospheric pressure is October (29.89"Hg).
Average wind speed in December
Guayanilla, PR
- Average wind speed in December: 6.7mph
The windiest month (with the highest average wind speed) is July (8mph).
The calmest month (with the lowest average wind speed) is November (5.6mph).
Average humidity in December
Guayanilla, PR
- Average humidity in December: 78%
The month with the highest relative humidity is November (80%).
The month with the lowest relative humidity is March (75%).
Average rainfall in December
Guayanilla, PR
- Average rainfall in December: 1.22"
The wettest month (with the highest rainfall) is September (3.58").
The driest month (with the least rainfall) is January (0.71").
Average rainfall days in December
Guayanilla, PR
- Average rainfall days in December: 16.3 days
The month with the highest number of rainy days is November (22.5 days).
The month with the least rainy days is February (14.8 days).
Average snowfall days in December
Guayanilla, PR
- Average snowfall days in December: 0 days
The month with the highest number of snowfall days is September (0.1 days).
The months with the least snowfall days are January, February, March, April, May, June, July, August, October, November and December (0 days).
Average daylight in December /
Average sunshine in December
Guayanilla, PR
- Average daylight in December: 11h and 6min
The month with the longest days is June (Average daylight: 13h and 12min).
The month with the shortest days is December (Average daylight: 11h and 6min).
- Average sunshine in December: 7h and 24min
The month with the most sunshine is June (Average sunshine: 11h and 18min).
The month with the least sunshine is November (Average sunshine: 7h and 6min).
Average sunshine days in December
Guayanilla, PR
- Average sunshine days in December: 9.4 days
The month with the most sunshine days is June (12.2 days).
The month with the least sunshine days is November (5.1 days).
Average UV index in December
Guayanilla, PR
- Average UV index in December: 6
The months with the highest UV index are April, May, June, July, August, September and October (UV index 7).
The months with the lowest UV index are January, February, March, November and December (UV index 6).
Average cloud cover in December
Guayanilla, PR
- Average cloud cover in December: 23
The month with the most cloud cover is May (Cloud cover 30).
The months with the least cloud cover are January and February (Cloud cover 22).
Average visibility in December
Guayanilla, PR
- 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).
