December weather forecast
Piti, GU

December in Piti, Guam, marks the culmination of the year with temperatures comfortably cooler compared to November. Despite a decrease in temperature, the weather remains pleasant enough for outdoor activities and beach visits. Transitioning from December to January, the weather retains its coolness, and a slight dip in temperatures is expected. The significant drop in rainfall with an average count of 2.99" (76mm) makes December one of the driest months in Piti, promising undisturbed, festive celebrations.

Temperature

December's arrival shows an average high-temperature of a still moderately hot 83.5°F (28.6°C), hardly different from the previous month. Piti, during December nights, records a temperature marginally cooler than the daytime average, at a still moderately hot 82°F (27.8°C).

Heat index

For most parts of December, the heat index is computed to be a tropical 91.4°F (33°C). Implement more safety precautions, heat cramps and heat exhaustion may happen. Persistent activity could induce heatstroke.
Consider that heat index readings are for situations in the shade and light wind. The direct sunshine could escalate the heat index values by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'feels like' or 'apparent temperature', is the result of factoring in humidity to the air temperature, indicating perceived warmth. Factors including metabolic differences, physical activity, and clothing are additional elements that influence the individual's temperature experience. It is essential to realize that direct sunlight can escalate the perceived temperature, increasing the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are highly important for children. In general, children are more at risk than adults because they sweat less. Furthermore, the large skin surface compared to their small bodies and the high heat production due to their actions contribute to this vulnerability.

Humidity

January, March through May, October through December, with an average relative humidity of 78%, are the most humid months in Piti, Guam.

Rainfall

In Piti, during December, the rain falls for 22.8 days and regularly aggregates up to 2.99" (76mm) of precipitation. In Piti, during the entire year, the rain falls for 288.5 days and collects up to 60.08" (1526mm) of precipitation.

Ocean temperature

In Piti, in December, the average water temperature is 83.1°F (28.4°C).
Note: Water temperature ranging from 77°F (25°C) to 84.2°F (29°C) is seen as very warm and delightful by everyone. During these temperatures, water activities become enjoyable, without causing discomfort for extended periods.

Daylight

The month with the shortest days is December, with an average of 11h and 24min of daylight.
On the first day of the month, sunrise is at 6:28 am and sunset at 5:52 pm. On the last day of December, in Piti, sunrise is at 6:43 am and sunset at 6:04 pm ChST.

Sunshine

In Piti, the average sunshine in December is 6.5h.

UV index

The months with the highest UV index in Piti are January through August, October through December, with an average maximum UV index of 7. A UV Index estimate of 6 to 7 represents a high threat to health from exposure to the Sun's UV rays for average individuals.
Note: A maximum UV index of 7 in December translates into the following recommendations:
Resist overexposure. Safeguarding from solar damage is indispensable. Stay in the shade and avoid direct Sun exposure from 10 a.m. to 4 p.m., a period when UV radiation is particularly strong, noting that parasols or canopies may not offer total sun protection. A hat with a broad brim is indispensable, filtering out up to half of UV rays. Heads up! Sand and water reflection magnifies the UV exposure from the Sun.