December Weather in Grantsville, United States

Last updated: June 24, 2025

In December, the average temperature in Grantsville, United States hovers around 1°C (34°F), with the minimum reaching a chilling -20°C (-4°F) and the maximum peaking at a mild 18°C (65°F). This month often brings 121 mm (4.8 in) of precipitation spread across 15 days, while the air stays refreshingly humid at an average of 85%.

December Temperature in Grantsville

In December in Grantsville, the average temperature is 1°C (34°F). Maximum temperatures can reach 18°C (65°F), while minimums can drop as low as -20°C (-4°F). It's a great time for travelers to experience a mix of chilly and mild weather, so prepare for varied conditions when exploring the area.

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

The chart illustrates December temperature patterns in Grantsville, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Grantsville, December typically has an average temperature of 1°C (34°F), with highs reaching up to 18°C (65°F) and lows dropping to around -20°C (-4°F).
JanFebMarAprMayJunJulAugSepOctNovDec283339495966716964543934
Data source: Temperature data for Grantsville 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 Grantsville

In Grantsville in December, the precipitation amount is 121 mm (4.8 in) during a period of 15 days.

December Precipitation Trends in Grantsville

The chart displays monthly precipitation patterns in Grantsville, 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 Grantsville, December typically receives around 121 mm (4.8 inches) of precipitation spread over approximately 15 days.
JanFebMarAprMayJunJulAugSepOctNovDec881321151371551501059911911585121
Data source: Precipitation data for December generated using information from the Copernicus Climate Change Service.
Choose your preferred precipitation unit

December Humidity in Grantsville

In Grantsville in December, humidity is 85%. With an average temperature of 1°C (34°F), this humidity feels like a biting chill that seeps into your bones, making outdoor travel uncomfortable and urging you to seek warmth indoors rather than explore the surroundings.

December Average Humidity in Grantsville

This chart illustrates the average monthly humidity levels in Grantsville, 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 Grantsville is approximately 85%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec86%86%86%84%78%79%70%59%68%80%87%85%
Data source: Humidity data for December generated using information from the Copernicus Climate Change Service.

December UV Index in Grantsville

In Grantsville 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 Grantsville, you can check the information here.

Maximum UV Index Levels in Grantsville for December

The chart shows the monthly maximum UV Index (UVI) for Grantsville 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 Grantsville typically reaches 3, which falls under the moderate exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec35710101010108753
Data source: Grantsville 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 Grantsville Compares to Other Months

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

This table compares monthly weather conditions in Grantsville, showing how December’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
 TemperaturePrecipitationHumidityUV
January Weather-2°C (29°F)88 mm (3.5 inches)86%moderate
February Weather1°C (33°F)132 mm (5.2 inches)86%moderate
March Weather4°C (39°F)115 mm (4.5 inches)86%high
April Weather9°C (49°F)137 mm (5.4 inches)84%very high
May Weather15°C (59°F)155 mm (6.1 inches)78%very high
June Weather19°C (67°F)150 mm (5.9 inches)79%very high
July Weather22°C (71°F)105 mm (4.1 inches)70%very high
August Weather21°C (70°F)99 mm (3.9 inches)59%very high
September Weather18°C (64°F)119 mm (4.7 inches)68%very high
October Weather12°C (54°F)115 mm (4.5 inches)80%high
November Weather4°C (40°F)85 mm (3.3 inches)86%moderate
December Weather1°C (34°F)121 mm (4.8 inches)85%moderate

Compare Grantsville's Climate with Cities Worldwide