January Weather in Herculaneum, United States

Last updated: June 24, 2025

In January, the average temperature in Herculaneum, United States hovers around 1°C (34°F), with extremes ranging from a chilly -20°C (-3°F) to a milder 20°C (68°F). Expect 77 mm (3.0 in) of precipitation over about 8 days, contributing to an average humidity of 82%. Embrace the diverse weather conditions that this month brings!

January Temperature in Herculaneum

In January in Herculaneum, the average temperature is 1°C (34°F). Maximums can reach 20°C (68°F), while minimums can drop as low as -20°C (-3°F). Be prepared for a wide range of temperatures when traveling during this time.

January Weather in Herculaneum: Daily Temperature Highs, Lows, and Averages

The chart illustrates January temperature patterns in Herculaneum, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Herculaneum, January typically has an average temperature of 1°C (34°F), with highs reaching up to 20°C (68°F) and lows dropping to around -20°C (-3°F).

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

January Precipitation in Herculaneum

In Herculaneum in January, the precipitation amount is 77 mm (3.0 in) distributed over 8 days.

January Precipitation Trends in Herculaneum

The chart displays monthly precipitation patterns in Herculaneum, with values for each month alongside January’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how January’s conditions compare to those of other months. In Herculaneum, January typically receives around 77 mm (3.0 inches) of precipitation spread over approximately 8 days.

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

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Millimeters (mm) Inches (in)

January Humidity in Herculaneum

In Herculaneum in January humidity is 82%. With an average temperature of 1°C (34°F), this humidity feels like walking through a thick fog, making it challenging to stay warm and comfortable while traveling.

January Average Humidity in Herculaneum

This chart illustrates the average monthly humidity levels in Herculaneum, with January’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In January, average humidity in Herculaneum is approximately 82%, offering insight into how humid the weather typically is during this month.

Data source: Humidity data for January generated using information from the Copernicus Climate Change Service.

January UV Index in Herculaneum

In Herculaneum in January, 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 Herculaneum, you can check the information here.

Maximum UV Index Levels in Herculaneum for January

The chart shows the monthly maximum UV Index (UVI) for Herculaneum in January, 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 January, the maximum UV index in Herculaneum typically reaches 3, which falls under the moderate exposure category.

Data source: Herculaneum January 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 January Weather in Herculaneum Compares to Other Months

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

This table compares monthly weather conditions in Herculaneum, showing how January’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	1°C (34°F)	77 mm (3.0 inches)	82%	moderate
February Weather	2°C (37°F)	84 mm (3.3 inches)	80%	moderate
March Weather	9°C (48°F)	132 mm (5.2 inches)	80%	high
April Weather	13°C (56°F)	137 mm (5.4 inches)	80%	very high
May Weather	19°C (67°F)	143 mm (5.6 inches)	82%	very high
June Weather	24°C (76°F)	88 mm (3.5 inches)	83%	extreme
July Weather	26°C (80°F)	89 mm (3.5 inches)	81%	very high
August Weather	25°C (76°F)	124 mm (4.9 inches)	80%	very high
September Weather	22°C (72°F)	68 mm (2.7 inches)	76%	very high
October Weather	15°C (59°F)	104 mm (4.1 inches)	76%	high
November Weather	7°C (45°F)	71 mm (2.8 inches)	85%	moderate
December Weather	4°C (40°F)	62 mm (2.5 inches)	86%	moderate