December weather forecast
Porto Santo Island, Portugal

December ushers in the cooler season on Porto Santo Island with temperatures averaging between 14.6°C (58.3°F) to 18.5°C (65.3°F). Despite being one of the cooler months, daytime remains relatively warm, drawing one to enjoy the calming beach views. As the year draws to a close, the weather becomes more unpredictable with fluctuating conditions, including astronomically shorter days, less sunshine, and a more biting breeze. The rainfall is slightly higher than November's levels, recording 56mm (2.2") over approximately 14 days, thus, umbrellas may become a common sight. During this period, Porto Santo Island retains a charm of its own, boasting its unique blend of mild winter days and comfortably cool nights.

Temperature

The arrival of December brings an average high-temperature of a refreshing 18.5°C (65.3°F), closely following the temperature pattern of November. Throughout December in Porto Santo Island, Portugal, a minimal difference from peak daytime temperatures is noted, marking a steady low-temperature average of 14.6°C (58.3°F).

Humidity

In December, the average relative humidity is 77%.

Rainfall

In Porto Santo Island, during December, the rain falls for 14 days and regularly aggregates up to 56mm (2.2") of precipitation. Throughout the year, there are 97 rainfall days, and 382mm (15.04") of precipitation is accumulated.

Sea temperature

In Porto Santo Island, Portugal, the average seawater temperature in December is 19.7°C (67.5°F).
Note: A majority do not enjoy swimming in water at 19.7°C (67.5°F). The difficulty in controlling breathing increases progressively as the temperature dips below 21°C (69.8°F).

Daylight

The month with the shortest days is December, with an average of 10h and 0min of daylight.
On the first day of December, sunrise is at 07:50 and sunset at 17:58. On the last day of the month, sunrise is at 08:08 and sunset at 18:08 WET.

Sunshine

The months with the least sunshine are January, February, November and December, with an average of 5h of sunshine.

UV index

January and December, with an average maximum UV index of 3, are months with the lowest UV index in Porto Santo Island. A UV Index of 3 to 5 symbolizes a medium health hazard from unsafe exposure to UV radiation for the average person.
Note: A daily maximum UV index of 3 in December translates into the following instructions:
Put precautions into practice - Guidance to elude sunburn is provided. It's recommended to limit sun exposure when its radiation is at its peak during midday. For minimizing sun-related eye damage, always choose sunglasses with UVA and UVB coverage.