December weather forecast
Hagåtña, GU

Welcoming December, Hagåtña, Guam presents a delightful medley of warm tropical weather and seasonal festivities. The city starts bracing for the holiday season with an air of anticipation and joy. A further reduction in rainfall to 2.99" (76mm) over 22.8 days provides the perfect backdrop for holiday shopping, Christmas parades, and festive celebrations. With relative comfort, festive spirit, and astounding visual appeal, December in Hagåtña offers a unique and mesmerising experience, concluding the calendar year on a high and joyful note.

Temperature

The arrival of December in Hagåtña marks a slight shift to an average high-temperature of a still moderately hot 83.5°F (28.6°C) from November's 84.2°F (29°C). A minor drop in temperature is observed from daytime highs during the nights of December, averaging a still warm 82°F (27.8°C).

Heat index

The heat index value for December is computed to be a tropical 91.4°F (33°C). Exercise enhanced safety steps, heat cramps and heat exhaustion are probable. Heatstroke could be a result of sustained activity.
It is essential to grasp that the heat index's numbers are for shade and light wind settings. Direct sunlight can potentially boost the heat index by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'apparent temperature' or 'real feel', evaluates the perceived heat by adding the effect of moisture in the air. Depending on the activity and the individual's heat perception, which may vary due to factors including wind, clothing, and metabolic variations, this effect remains subjective. Keep aware, the sun, when shining directly, can intensify the heat experience, pushing the heat index up by 15 Fahrenheit (8 Celsius) degrees. Heat index values are extremely significant for children. Kids are usually in more danger than grown-ups as they tend to sweat less. Plus, their bigger skin surface in relation to their small frames and increased heat generation due to their activity level make them more susceptible.

Humidity

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

Rainfall

In Hagåtña, in December, it is raining for 22.8 days, with typically 2.99" (76mm) of accumulated precipitation. In Hagåtña, during the entire year, the rain falls for 288.5 days and collects up to 60.08" (1526mm) of precipitation.

Ocean temperature

In Hagåtña, Guam, in December, the average water temperature is 83.1°F (28.4°C).
Note: Temperatures between 77°F (25°C) and 84.2°F (29°C) are excellent for swimming, diving, and other water activities, providing comfort and enjoyment for extended periods without discomfort.

Daylight

The month with the shortest days is December, with an average of 11h and 18min of daylight.
On the first day of the month, sunrise is at 6:28 am and sunset at 5:51 pm. On the last day of December, sunrise is at 6:43 am and sunset at 6:04 pm ChST.

Sunshine

In December, the average sunshine is 6.5h.

UV index

January through August, October through December, with an average maximum UV index of 7, are months with the highest UV index in Hagåtña. A UV Index of 6 to 7 symbolizes a high health risk from unsafe exposure to UV radiation for the average person.
Note: The maximum daily UV index of 7 in December interprets into the following recommendations:
Beware of overexposure. Fair-skinned individuals risk burning in less than 20 minutes. Avoid direct exposure to the Sun between 10 a.m. and 4 p.m., the peak period for UV radiation, noting that objects like parasols or canopies might not offer complete sun protection. In the presence of strong sunlight, it's crucial to wear sunglasses that ward off UVA and UVB rays. Alert! The Sun's UV rays are heightened by the reflection of sand and water.