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December Weather in Saint Helena, United States

Last updated: June 24, 2025

In December, the average temperature in Saint Helena, United States is a mild 9°C (49°F). Prepare for temperature fluctuations, with a minimum dipping as low as -1°C (30°F) and a maximum reaching 23°C (74°F). Expect about 95 mm (3.7 in) of precipitation over 8 days, accompanied by an average humidity of 84%. Make sure to pack accordingly!

December Temperature in Saint Helena

In December in Saint Helena, the average temperature is 9°C (49°F), with maximums reaching up to 23°C (74°F) and minimums dipping as low as -1°C (30°F). Be prepared for a range of temperatures while traveling, ensuring you have both warm and cool clothing options.

December Weather in Saint Helena: Daily Temperature Highs, Lows, and Averages

The chart illustrates December temperature patterns in Saint Helena, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Saint Helena, December typically has an average temperature of 9°C (49°F), with highs reaching up to 23°C (74°F) and lows dropping to around -1°C (30°F).
JanFebMarAprMayJunJulAugSepOctNovDec495153586471737370645448
Data source: Temperature data for Saint Helena generated using information from the Copernicus Climate Change Service.
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The average of daily temperatures (24 hours) calculated across all days in the month.

December Precipitation in Saint Helena

In Saint Helena in December, the total precipitation amount is 95 mm (3.7 in) spread over 8 days.

December Precipitation Trends in Saint Helena

The chart displays monthly precipitation patterns in Saint Helena, 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 Saint Helena, December typically receives around 95 mm (3.7 inches) of precipitation spread over approximately 8 days.
JanFebMarAprMayJunJulAugSepOctNovDec1371419239232102385195
Data source: Precipitation data for December generated using information from the Copernicus Climate Change Service.
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December Humidity in Saint Helena

In Saint Helena in December, humidity is 84%. With an average temperature of 9°C (49°F), this humidity feels like a chilly embrace, making travel uncomfortable as the dampness seeps into your clothes and lingers in the air, leaving you feeling cool yet clammy.

December Average Humidity in Saint Helena

This chart illustrates the average monthly humidity levels in Saint Helena, 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 Saint Helena is approximately 84%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec86%84%83%80%80%76%70%66%68%72%84%84%
Data source: Humidity data for December generated using information from the Copernicus Climate Change Service.

December UV Index in Saint Helena

In Saint Helena in December, the maximum UV index is 3, which corresponds to a moderate Exposure Category. The time to burn is approximately 30 minutes. For more details on the hourly UV index in Saint Helena, you can check the information here.

Maximum UV Index Levels in Saint Helena for December

The chart shows the monthly maximum UV Index (UVI) for Saint Helena 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 Saint Helena typically reaches 3, which falls under the moderate exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec3579101111109643
Data source: Saint Helena 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 Saint Helena Compares to Other Months

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

This table compares monthly weather conditions in Saint Helena, showing how December’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
 TemperaturePrecipitationHumidityUV
January Weather9°C (49°F)137 mm (5.4 inches)86%moderate
February Weather10°C (51°F)141 mm (5.6 inches)84%moderate
March Weather11°C (53°F)92 mm (3.6 inches)83%high
April Weather15°C (59°F)39 mm (1.5 inches)80%very high
May Weather18°C (64°F)23 mm (0.9 inches)80%very high
June Weather22°C (72°F)2 mm (0.1 inches)76%extreme
July Weather23°C (74°F)0 mm (0.0 inches)70%extreme
August Weather23°C (73°F)0 mm (0.0 inches)66%very high
September Weather21°C (71°F)2 mm (0.1 inches)68%very high
October Weather18°C (64°F)38 mm (1.5 inches)72%high
November Weather12°C (55°F)51 mm (2.0 inches)84%moderate
December Weather9°C (49°F)95 mm (3.7 inches)84%moderate

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