May Weather in Heidelberg, South Africa

Last updated: August 31, 2025

In May, the average temperature in Heidelberg, South Africa hovers around 13°C (56°F). Expect a minimum drop to -1°C (31°F) and a pleasant maximum of 26°C (79°F). With an average humidity of 82% and 14 mm (0.5 in) of precipitation over just 1 day, it's a month where layers and an umbrella might come in handy!

May Temperature in Heidelberg

In May in Heidelberg, the average temperature is 13°C (56°F), with maximums reaching 26°C (79°F) and minimums dipping as low as -1°C (31°F). Be prepared for a wide range of temperatures during your travels, ensuring you pack both warm and lighter clothing options.

May Weather in Heidelberg: Daily Temperature Highs, Lows, and Averages

The chart illustrates May temperature patterns in Heidelberg, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Heidelberg, May typically has an average temperature of 13°C (56°F), with highs reaching up to 26°C (79°F) and lows dropping to around -1°C (31°F).

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

May Precipitation in Heidelberg

In Heidelberg in May, the precipitation amount is 14 mm (0.5 in) over the course of 1 day.

May Precipitation Trends in Heidelberg

The chart displays monthly precipitation patterns in Heidelberg, with values for each month alongside May’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how May’s conditions compare to those of other months. In Heidelberg, May typically receives around 14 mm (0.5 inches) of precipitation spread over approximately 1 days.

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

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Millimeters (mm) Inches (in)

May Humidity in Heidelberg

In Heidelberg in May, humidity is 82%. With an average temperature of 13°C (56°F), this humidity feels like a damp blanket wrapping around you, making it feel much cooler than it is and creating a heavy atmosphere that can be exhausting for travelers.

May Average Humidity in Heidelberg

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

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

May UV Index in Heidelberg

In Heidelberg in May, the maximum UV index is 7, which corresponds to the high Exposure Category. This means that the time to burn is approximately 25 minutes. For more detailed information, you can check the Hourly UV Index in Heidelberg.

Maximum UV Index Levels in Heidelberg for May

The chart shows the monthly maximum UV Index (UVI) for Heidelberg in May, 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 May, the maximum UV index in Heidelberg typically reaches 7, which falls under the high exposure category.

Data source: Heidelberg May 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 May Weather in Heidelberg Compares to Other Months

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

This table compares monthly weather conditions in Heidelberg, showing how May’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	21°C (69°F)	121 mm (4.8 inches)	79%	extreme
February Weather	20°C (69°F)	126 mm (5.0 inches)	77%	extreme
March Weather	19°C (67°F)	72 mm (2.8 inches)	77%	extreme
April Weather	16°C (62°F)	60 mm (2.4 inches)	81%	very high
May Weather	13°C (56°F)	14 mm (0.5 inches)	82%	high
June Weather	11°C (51°F)	5 mm (0.2 inches)	73%	high
July Weather	10°C (51°F)	2 mm (0.1 inches)	71%	high
August Weather	14°C (57°F)	2 mm (0.1 inches)	68%	very high
September Weather	18°C (64°F)	9 mm (0.4 inches)	74%	extreme
October Weather	19°C (66°F)	66 mm (2.6 inches)	74%	extreme
November Weather	20°C (69°F)	106 mm (4.2 inches)	82%	extreme
December Weather	20°C (69°F)	156 mm (6.1 inches)	81%	extreme