December Weather in Lammi, Finland

Last updated: August 23, 2025

In December, the average temperature in Lammi, Finland hovers around -2°C (28°F), with potential extremes ranging from a chilly -21°C (-5°F) to a milder 6°C (42°F). This month experiences an average precipitation of 67 mm (2.6 in) over 14 days, contributing to an average humidity level of 95%. Prepare for a brisk and damp atmosphere!

December Temperature in Lammi

In December in Lammi, the average temperature is -2°C (28°F), with maximums reaching 6°C (42°F) and minimums dropping as low as -21°C (-5°F). Be prepared for cold weather and pack appropriately for your travels to this chilly destination.

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

The chart illustrates December temperature patterns in Lammi, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Lammi, December typically has an average temperature of -2°C (28°F), with highs reaching up to 6°C (42°F) and lows dropping to around -21°C (-5°F).

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

December Precipitation in Lammi

In Lammi in December, the precipitation amount is 67 mm (2.6 in) spread over 14 days.

December Precipitation Trends in Lammi

The chart displays monthly precipitation patterns in Lammi, 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 Lammi, December typically receives around 67 mm (2.6 inches) of precipitation spread over approximately 14 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 Lammi

In Lammi in December humidity is 95%. With an average temperature of -2°C (28°F), this humidity feels like a damp, frigid chill that seeps into your bones, making traveling uncomfortable and the air heavy with a biting cold that dampens your spirits.

December Average Humidity in Lammi

This chart illustrates the average monthly humidity levels in Lammi, 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 Lammi is approximately 95%, 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 Lammi

In Lammi 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 Lammi.

Maximum UV Index Levels in Lammi for December

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

Data source: Lammi 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 Lammi Compares to Other Months

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

This table compares monthly weather conditions in Lammi, 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)	48 mm (1.9 inches)	97%	low
February Weather	-5°C (24°F)	42 mm (1.7 inches)	95%	low
March Weather	-2°C (29°F)	44 mm (1.7 inches)	93%	moderate
April Weather	3°C (38°F)	47 mm (1.8 inches)	86%	moderate
May Weather	10°C (50°F)	58 mm (2.3 inches)	75%	moderate
June Weather	16°C (61°F)	69 mm (2.7 inches)	75%	high
July Weather	17°C (63°F)	83 mm (3.3 inches)	80%	high
August Weather	16°C (61°F)	81 mm (3.2 inches)	83%	moderate
September Weather	11°C (52°F)	67 mm (2.6 inches)	90%	moderate
October Weather	6°C (43°F)	78 mm (3.1 inches)	93%	low
November Weather	2°C (36°F)	53 mm (2.1 inches)	94%	low
December Weather	-2°C (28°F)	67 mm (2.6 inches)	95%	low