nomadseason

December Weather in Merton, United States

Last updated: June 24, 2025

In December, the average temperature in Merton, United States hovers around -1°C (30°F). While it can dip as low as -23°C (-8°F), temperatures may also reach a pleasant 19°C (66°F). Expect 46 mm (1.8 in) of precipitation spread over 6 days, with an average humidity of 81%. Embrace the chill, but be prepared for some cozy indoor time!

December Temperature in Merton

In December in Merton, the average temperature is -1°C (30°F). Maximum temperatures can reach up to 19°C (66°F), while the minimum can plummet to as low as -23°C (-8°F). Travelers should be prepared for a wide range of temperatures during this month, ensuring they pack accordingly to enjoy their visit.

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

The chart illustrates December temperature patterns in Merton, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Merton, December typically has an average temperature of -1°C (30°F), with highs reaching up to 19°C (66°F) and lows dropping to around -23°C (-8°F).
JanFebMarAprMayJunJulAugSepOctNovDec222436455869747165523730
Data source: Temperature data for Merton generated using information from the Copernicus Climate Change Service.
Choose your preferred temperature unit
The average of daily temperatures (24 hours) calculated across all days in the month.

December Precipitation in Merton

In Merton in December, the precipitation amount is 46 mm (1.8 in) over a span of 6 days.

December Precipitation Trends in Merton

The chart displays monthly precipitation patterns in Merton, 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 Merton, December typically receives around 46 mm (1.8 inches) of precipitation spread over approximately 6 days.
JanFebMarAprMayJunJulAugSepOctNovDec5451611071261069788981124646
Data source: Precipitation data for December generated using information from the Copernicus Climate Change Service.
Choose your preferred precipitation unit

December Humidity in Merton

In Merton in December, humidity is 81%. With an average temperature of -1°C (30°F), this humidity feels like an extra layer of chill settles in, making travel uncomfortable and the cold air cling to your skin, dampening the experience with every breath.

December Average Humidity in Merton

This chart illustrates the average monthly humidity levels in Merton, 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 Merton is approximately 81%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec85%85%85%85%78%80%78%76%79%83%88%82%
Data source: Humidity data for December generated using information from the Copernicus Climate Change Service.

December UV Index in Merton

In Merton in December, the maximum UV index is 2, which corresponds to a low exposure category. With this level of UV radiation, the time to burn is approximately 45 minutes. To learn more about the hourly UV index in Merton, you can visit Hourly UV Index in Merton.

Maximum UV Index Levels in Merton for December

The chart shows the monthly maximum UV Index (UVI) for Merton 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 Merton typically reaches 2, which falls under the low exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec34589101097532
Data source: Merton 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 Merton Compares to Other Months

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

This table compares monthly weather conditions in Merton, showing how December’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
 TemperaturePrecipitationHumidityUV
January Weather-5°C (23°F)54 mm (2.1 inches)85%moderate
February Weather-5°C (24°F)51 mm (2.0 inches)85%moderate
March Weather2°C (36°F)61 mm (2.4 inches)85%moderate
April Weather7°C (45°F)107 mm (4.2 inches)85%very high
May Weather14°C (58°F)126 mm (5.0 inches)78%very high
June Weather20°C (69°F)106 mm (4.2 inches)80%very high
July Weather23°C (74°F)97 mm (3.8 inches)78%very high
August Weather22°C (71°F)87 mm (3.4 inches)76%very high
September Weather18°C (65°F)98 mm (3.9 inches)79%high
October Weather11°C (52°F)112 mm (4.4 inches)83%moderate
November Weather3°C (37°F)46 mm (1.8 inches)88%moderate
December Weather-1°C (30°F)46 mm (1.8 inches)81%low

Compare Merton's Climate with Cities Worldwide