January Weather in Swansea, United States

Last updated: June 24, 2025

In January, the average temperature in Swansea, United States is a brisk 9°C (49°F). Expect temperatures to vary significantly, with a minimum of -9°C (16°F) and a maximum that can reach up to 27°C (81°F). Additionally, be prepared for 83 mm (3.3 in) of precipitation spread over 9 days and an average humidity level of 86%—ideal conditions for enjoying cozy indoor activities!

January Temperature in Swansea

In January in Swansea, the average temperature is 9°C (49°F). The maximum can reach 27°C (81°F), while the minimum can drop as low as -9°C (16°F). Travelers should be prepared for a wide range of temperatures and pack accordingly.

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

The chart illustrates January temperature patterns in Swansea, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Swansea, January typically has an average temperature of 9°C (49°F), with highs reaching up to 27°C (81°F) and lows dropping to around -9°C (16°F).

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

January Precipitation in Swansea

In Swansea in January, the precipitation amount is 83 mm (3.3 in) over the course of 9 days.

January Precipitation Trends in Swansea

The chart displays monthly precipitation patterns in Swansea, 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 Swansea, January typically receives around 83 mm (3.3 inches) of precipitation spread over approximately 9 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 Swansea

In Swansea in January, humidity is 86%. With an average temperature of 9°C (49°F), this humidity feels like a damp chill in the air, making travel uncomfortable as the moisture clings to your skin and thickens the atmosphere, creating a sense of heaviness that can tire you quickly.

January Average Humidity in Swansea

This chart illustrates the average monthly humidity levels in Swansea, 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 Swansea is approximately 86%, 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 Swansea

In Swansea in January, the maximum UV index reaches 4, which corresponds to a moderate Exposure Category. With a time to burn of 30 minutes, it’s important to take precautions to protect your skin. You can find more details in the Hourly UV Index in Swansea for better planning.

Maximum UV Index Levels in Swansea for January

The chart shows the monthly maximum UV Index (UVI) for Swansea 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 Swansea typically reaches 4, which falls under the moderate exposure category.

Data source: Swansea 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 Swansea Compares to Other Months

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

This table compares monthly weather conditions in Swansea, showing how January’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	9°C (49°F)	83 mm (3.3 inches)	86%	moderate
February Weather	12°C (54°F)	100 mm (3.9 inches)	81%	high
March Weather	15°C (58°F)	76 mm (3.0 inches)	81%	very high
April Weather	19°C (66°F)	112 mm (4.4 inches)	79%	very high
May Weather	23°C (74°F)	105 mm (4.2 inches)	75%	extreme
June Weather	26°C (79°F)	121 mm (4.8 inches)	75%	extreme
July Weather	27°C (82°F)	154 mm (6.1 inches)	80%	extreme
August Weather	27°C (81°F)	141 mm (5.6 inches)	81%	extreme
September Weather	25°C (77°F)	98 mm (3.9 inches)	83%	very high
October Weather	20°C (69°F)	71 mm (2.8 inches)	78%	very high
November Weather	13°C (55°F)	61 mm (2.4 inches)	85%	high
December Weather	10°C (51°F)	129 mm (5.1 inches)	87%	moderate