December Weather in Sumy, Ukraine

Last updated: August 28, 2025

In December, the average temperature in Sumy, Ukraine hovers around -1°C (30°F). Temperatures can dip as low as -21°C (-5°F), while occasionally peaking at a maximum of 11°C (51°F). This month also brings about 69 mm (2.7 in) of precipitation spread over 13 days, contributing to an average humidity level of 94%. Prepare for a chilly and damp experience!

December Temperature in Sumy

In December in Sumy, the average temperature is -1°C (30°F), with maximums reaching 11°C (51°F) and minimums plummeting to -21°C (-5°F). Travelers should prepare for a range of conditions, making warm clothing essential for this chilly destination.

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

The chart illustrates December temperature patterns in Sumy, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Sumy, December typically has an average temperature of -1°C (30°F), with highs reaching up to 11°C (51°F) and lows dropping to around -21°C (-5°F).

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

December Precipitation in Sumy

In Sumy in December, the precipitation amount is 69 mm (2.7 in) over the course of 13 days.

December Precipitation Trends in Sumy

The chart displays monthly precipitation patterns in Sumy, 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 Sumy, December typically receives around 69 mm (2.7 inches) of precipitation spread over approximately 13 days.

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

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Millimeters (mm) Inches (in)

December Humidity in Sumy

In Sumy in December humidity is 94%. With an average temperature of -1°C (30°F), this humidity feels like a chilling blanket that wraps around you, making every outdoor excursion uncomfortable and damp, as you battle the cold air that clings to your skin and seeps into your clothes.

December Average Humidity in Sumy

This chart illustrates the average monthly humidity levels in Sumy, 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 Sumy is approximately 94%, 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 Sumy

In Sumy in December, the maximum UV index is 1, which corresponds to a low Exposure Category. This means you have a time to burn of 45 minutes. For more details, you can check the Hourly UV Index in Sumy.

Maximum UV Index Levels in Sumy for December

The chart shows the monthly maximum UV Index (UVI) for Sumy 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 Sumy typically reaches 1, which falls under the low exposure category.

Data source: Sumy 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 Sumy Compares to Other Months

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

This table compares monthly weather conditions in Sumy, showing how December’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	-4°C (25°F)	43 mm (1.7 inches)	92%	low
February Weather	-3°C (26°F)	45 mm (1.8 inches)	93%	low
March Weather	1°C (35°F)	40 mm (1.6 inches)	90%	moderate
April Weather	9°C (48°F)	40 mm (1.6 inches)	79%	moderate
May Weather	15°C (59°F)	64 mm (2.5 inches)	66%	high
June Weather	20°C (68°F)	58 mm (2.3 inches)	65%	very high
July Weather	21°C (69°F)	84 mm (3.3 inches)	55%	very high
August Weather	21°C (69°F)	28 mm (1.1 inches)	49%	high
September Weather	15°C (60°F)	39 mm (1.5 inches)	69%	high
October Weather	9°C (49°F)	36 mm (1.4 inches)	84%	moderate
November Weather	2°C (36°F)	37 mm (1.4 inches)	92%	low
December Weather	-1°C (30°F)	69 mm (2.7 inches)	94%	low