December Weather in Longwood, Saint Helena, Ascension and Tristan da Cunha

Last updated: August 31, 2025

In December, the average temperature in Longwood, Saint Helena, Ascension and Tristan da Cunha is a pleasant 21°C (70°F), with a minimum of 19°C (67°F) and a maximum of 23°C (73°F). Expect 10 mm (0.4 in) of precipitation over 0 days, and enjoy the typically 80% humidity that adds to the region's charm.

December Temperature in Longwood

In December in Longwood, the average temperature is 21°C (70°F), with maximums reaching 23°C (73°F) and minimums dropping to as low as 19°C (67°F). This mild climate makes Longwood an ideal destination for travelers looking for pleasant weather.

December Weather in Longwood: Daily Temperature Highs, Lows, and Averages

The chart illustrates December temperature patterns in Longwood, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Longwood, December typically has an average temperature of 21°C (70°F), with highs reaching up to 23°C (73°F) and lows dropping to around 19°C (67°F).

Data source: Temperature data for Longwood generated using information from the Copernicus Climate Change Service.

December Precipitation in Longwood

In Longwood in December, the precipitation amount is 10 mm (0.4 in) during a total of 0 days.

December Precipitation Trends in Longwood

The chart displays monthly precipitation patterns in Longwood, with values for each month alongside December’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how December’s conditions compare to those of other months. In Longwood, December typically receives around 10 mm (0.4 inches) of precipitation spread over approximately 0 days.

Data source: Precipitation data for December generated using information from the Copernicus Climate Change Service.

Choose your preferred precipitation unit

Millimeters (mm) Inches (in)

December Humidity in Longwood

In Longwood in December humidity is 80%. With an average temperature of 21°C (70°F), this humidity feels like a warm, enveloping blanket that can make even short walks feel draining, urging travelers to seek shade or a cool drink frequently.

December Average Humidity in Longwood

This chart illustrates the average monthly humidity levels in Longwood, with December’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In December, average humidity in Longwood is approximately 80%, offering insight into how humid the weather typically is during this month.

Data source: Humidity data for December generated using information from the Copernicus Climate Change Service.

December UV Index in Longwood

In Longwood in December, the maximum UV index reaches an alarming 15, which falls into the extreme Exposure Category. With a time to burn of just 10 minutes, it's crucial to take precautions. For detailed information, you can check the Hourly UV Index in Longwood.

Maximum UV Index Levels in Longwood for December

The chart shows the monthly maximum UV Index (UVI) for Longwood in December, representing the highest UV radiation level. The UVI measures the intensity of ultraviolet radiation from the sun, indicating the potential risk of sunburn and UV-related health issues. In December, the maximum UV index in Longwood typically reaches 15, which falls under the extreme exposure category.

Data source: Longwood December UVI data generated using information from the Copernicus Climate Change Service.

UV Risk Categories

Extreme (11+): Avoid the sun, stay in shade.
Very High (8-10): Limit sun exposure.
High (6-7): Use SPF 30+ and protective clothing.
Moderate (3-5): Midday shade recommended.
Low (0-2): No protection needed.

How December Weather in Longwood Compares to Other Months

Weather in Longwood varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in Longwood, focusing on differences in temperature, rainfall, humidity, and UV levels.

This table compares monthly weather conditions in Longwood, showing how December’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	23°C (73°F)	10 mm (0.4 inches)	79%	extreme
February Weather	24°C (75°F)	12 mm (0.5 inches)	81%	extreme
March Weather	24°C (76°F)	16 mm (0.6 inches)	82%	extreme
April Weather	24°C (75°F)	14 mm (0.6 inches)	81%	extreme
May Weather	23°C (73°F)	12 mm (0.5 inches)	78%	very high
June Weather	22°C (71°F)	14 mm (0.5 inches)	74%	very high
July Weather	21°C (69°F)	12 mm (0.5 inches)	75%	very high
August Weather	20°C (68°F)	14 mm (0.6 inches)	76%	very high
September Weather	20°C (67°F)	13 mm (0.5 inches)	78%	extreme
October Weather	19°C (67°F)	11 mm (0.4 inches)	80%	extreme
November Weather	20°C (68°F)	10 mm (0.4 inches)	81%	extreme
December Weather	21°C (70°F)	10 mm (0.4 inches)	80%	extreme