May Weather in London, United States

Last updated: June 24, 2025

In London, United States, the average temperature in May is a pleasant 21°C (70°F). However, temperatures can vary widely, with minimums dropping to 5°C (42°F) and maximums reaching a scorching 34°C (93°F). During this month, you can expect around 198 mm (7.8 in) of precipitation spread over 14 days, coupled with a high average humidity of 82%.

May Temperature in London

In May in London, the average temperature is 21°C (70°F), with maximums reaching 34°C (93°F) and minimums dropping as low as 5°C (42°F). This range makes London a perfect destination for travelers seeking both warm days and cooler evenings.

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

The chart illustrates May temperature patterns in London, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In London, May typically has an average temperature of 21°C (70°F), with highs reaching up to 34°C (93°F) and lows dropping to around 5°C (42°F).

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

May Precipitation in London

In London in May, the total precipitation amount is 198 mm (7.8 in) over a duration of 14 days.

May Precipitation Trends in London

The chart displays monthly precipitation patterns in London, 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 London, May typically receives around 198 mm (7.8 inches) of precipitation spread over approximately 14 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 London

In London in May, humidity is 82%. With an average temperature of 21°C (70°F), this humidity feels like a warm, sticky embrace that can quickly lead to discomfort for travelers, making outdoor activities less enjoyable and requiring frequent breaks for hydration.

May Average Humidity in London

This chart illustrates the average monthly humidity levels in London, 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 London 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 London

In London in May, the maximum UV index reaches 10, which corresponds to a very high Exposure Category. With a time to burn of just 15 minutes, it's crucial to take precautions. For more detailed information, you can check the Hourly UV Index in London.

Maximum UV Index Levels in London for May

The chart shows the monthly maximum UV Index (UVI) for London 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 London typically reaches 10, which falls under the very high exposure category.

Data source: London 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 London Compares to Other Months

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

This table compares monthly weather conditions in London, showing how May’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	5°C (41°F)	88 mm (3.4 inches)	82%	moderate
February Weather	7°C (44°F)	135 mm (5.3 inches)	79%	high
March Weather	12°C (54°F)	140 mm (5.5 inches)	77%	very high
April Weather	15°C (60°F)	150 mm (5.9 inches)	78%	very high
May Weather	21°C (70°F)	198 mm (7.8 inches)	82%	very high
June Weather	26°C (78°F)	122 mm (4.8 inches)	81%	extreme
July Weather	27°C (82°F)	86 mm (3.4 inches)	75%	extreme
August Weather	26°C (80°F)	127 mm (5.0 inches)	61%	very high
September Weather	24°C (76°F)	65 mm (2.6 inches)	59%	very high
October Weather	17°C (64°F)	103 mm (4.1 inches)	69%	high
November Weather	10°C (51°F)	88 mm (3.4 inches)	82%	moderate
December Weather	8°C (46°F)	100 mm (3.9 inches)	87%	moderate