May Weather in London, United Kingdom

Last updated: March 17, 2025

In May, London showcases a delightful mix of spring warmth and occasional showers. With a maximum temperature reaching 25°C (78°F) and an average of 13°C (55°F), the city experiences a pleasant climate. However, be prepared for cooler moments as temperatures can drop to a minimum of 1°C (35°F). Rainfall is moderate, with 62 mm (2.5 in) spread over approximately 11 days, contributing to a relative humidity of 79%. This makes May a perfect time to explore the city's vibrant parks and gardens, where nature is in full bloom, but don't forget to bring your umbrella for unexpected drizzles!

May Temperature in London

In May, London begins to shed its winter coat, welcoming a mild transformation as temperatures gradually rise. With a minimum temperature of 1°C (35°F) and an average of 13°C (55°F), the city experiences a noticeable warmth compared to the earlier months. This month boasts a maximum of 25°C (78°F), making it an ideal time for locals and tourists to enjoy outdoor activities amid the blooming sights of spring. As the chill of previous months fades, May serves as a gentle bridge into the summer, with increasingly pleasant weather mirroring the vibrant energy of the city.

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.
JanFebMarAprMayJunJulAugSepOctNovDec414345495562656459534643
Data source: Temperature data for London generated using information from the Copernicus Climate Change Service.
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The average of daily temperatures (24 hours) calculated across all days in the month.

May Precipitation in London

In May, London experiences a notable uptick in precipitation, with an average of 62 mm (2.5 inches) falling over roughly 11 days. This increase marks a shift from the drier April, which recorded just 33 mm (1.3 inches) across 8 days. As spring approaches its zenith, the city often witnesses this transitional weather, bringing lush greenery to parks and gardens. This pattern reflects a broader trend in London's climate, where late spring and early summer months consistently yield higher rainfall, especially when compared to the preceding months. Overall, May calls for an umbrella, as residents embrace the refreshing rains that herald the vibrant season ahead.

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.
JanFebMarAprMayJunJulAugSepOctNovDec545354336277647045845284
Data source: Precipitation data for May generated using information from the Copernicus Climate Change Service.
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May Humidity in London

As May rolls into London, the humidity begins to dip significantly, settling at a comfortable 79%. This marks a notable drop from the earlier months, where levels hovered above 85%. The transition from a damp winter to a more temperate spring is evident, allowing residents to enjoy the blooming scenery with slightly fresher air. After May, humidity levels see a minor increase in June, hinting at the warmer months ahead. Overall, this gradual decline in moisture levels throughout spring reflects London's shifting climate, offering a pleasant reprieve before the heat of summer takes hold.

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, allowing you to see how May's humidity levels compare to other months.
JanFebMarAprMayJunJulAugSepOctNovDec91%89%86%85%79%81%71%76%82%91%92%92%
Data source: Humidity data for May generated using information from the Copernicus Climate Change Service.

May UV Index in London

As spring transitions into early summer, May sees a notable rise in the UV Index in London, climbing to 7, which falls into the high exposure category. This increase signifies a more intense sun, with a reduced burn time of just 25 minutes for unprotected skin. Compared to the previous months, where the indices were relatively low to moderate (peaking at 5 in April), May clearly marks the onset of a season where sun safety becomes crucial. With the impending very high indices of summer months, it’s essential to stay vigilant and protect your skin. For more insights on UV levels throughout the year, visit London UV Index.

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.
JanFebMarAprMayJunJulAugSepOctNovDec124578876421
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.

May Sunshine in London

May shines as a bright highlight in London's yearly sunshine calendar, boasting 398 hours of sunlight. As spring blooms into summer, this month stands out with a significant leap from the 319 hours recorded in April, showcasing the city’s transition into longer, sunnier days. Following May, June and July continue to bask in sunlight, with both months exceeding 389 hours, yet May retains a distinct charm as the peak of just blossoming warmth. As summer wanes into August, sunshine hours gradually decline to 368, hinting at the impending shifts of autumn. Overall, May encapsulates the essence of spring's vibrancy, offering the promise of warmth that the city eagerly anticipates after the dreary winter months.

Monthly Sunshine Duration in London: May Highlighted

The May sunshine duration represents the total number of hours London experiences direct sunlight during the month of May, excluding cloudy or obstructed periods. This chart compares the sunshine duration of May with the other months of the year.
JanFebMarAprMayJunJulAugSepOctNovDec98h148h210h319h398h389h404h368h300h241h144h109h
Data source: London May Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in London During May

As spring transitions into summer, May in London offers a notable chance of sunny weather, with approximately 33% of the days graced by sunshine. This marks a decline from the preceding month of April, where the likelihood of sunshine peaks at 49%, suggesting that while May retains decent potential for sunny spells, it does not quite hold the same allure. Interestingly, this trend of fluctuating sunshine continues into June and July, where chances rise again, hinting at a dynamic rather than consistent weather pattern. In this vibrant month, Londoners can anticipate a mix of sunny and cloudy days, perfect for outdoor activities, while still being mindful that the typical unpredictability of British weather keeps the element of surprise alive.

Percentage of Sunny Days in May in London

The chart illustrates the percentage of sunny days in London throughout the year, with May highlighted. It highlights the variation in sunshine across each month and provides an overview of the typical frequency of sunny days, offering insights into how often London experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec19%25%29%49%33%28%38%25%29%25%32%17%
Data source: London May chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in London in May

As May arrives in London, residents revel in a delightful increase in daylight duration, enjoying an impressive 15 hours of sunlight—a notable leap from 13 hours in April. This uplifting trend continues into the summer months, peaking at 16 hours in both June and July, creating the perfect ambiance for outdoor activities and longer evenings. As the year progresses, however, daylight gradually diminishes, decreasing to 14 hours in August and tapering off to 10 hours in October. The stark contrast between the bright, long days of spring and summer and the shorter, darker days of winter underscores the rhythm of London’s seasons, inviting both residents and visitors to make the most of the sun-filled days while they last.

Average Daylight Hours in London for May

The chart illustrates the variation in daylight duration in London throughout the year, with May highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec8h 23m9h 58m11h 55m13h 54m15h 38m16h 32m16h 3m14h 30m12h 35m10h 36m8h 50m7h 53m
Data source: London daylight hours, calculated by summing the hours between sunrise and sunset for each day.

May Winds in London

In May, London experiences a gentle embrace of winds, with an average speed of 4.2 m/s (9 mph), paralleling the breezy conditions seen in January but distinctly lighter than the spring gusts of March. As temperatures rise and flowers bloom, the winds remain consistent, reflecting a slight increase from the calming breezes of April, which saw an average speed of 3.5 m/s (8 mph). This stability in May's winds hints at the transition into summer, marking it as a time when the city's parks and gardens come alive, inviting both residents and tourists to relish the mild conditions. Notably, May's wind speed is part of a trend where the spring months show a general ebb and flow, with the winds declining into the summer months while hinting at a return to brisker conditions as the year progresses into autumn.

Average May Wind Speed in London

The chart displays monthly wind speed patterns in London, with values for each month shown alongside May's data, which is highlighted for easy comparison. It illustrates the average wind speed, offering insights into how May's wind conditions compare to the rest of the year.
JanFebMarAprMayJunJulAugSepOctNovDec4.24.74.43.54.2 m/s3.13.33.83.34.43.84.4
Data source: London May wind data, generated using information from the Copernicus Climate Change Service.

How May Weather in London Compares to Other Months

The weather in London changes throughout the year, offering a unique experience in each season. Below is a month-by-month comparison of May's weather with other months, highlighting differences in temperature, precipitation, and other key factors. Click on each section to discover seasonal trends in London and find detailed weather information for every month.

May weather in London is characterized by a significant warming trend, with temperatures ranging from a minimum of 1°C (35°F) to a pleasant maximum of 25°C (78°F), resulting in an average of 13°C (55°F). The month sees around 62 mm (2.5 in) of precipitation spread over approximately 11 days, with humidity levels at 79%. In contrast, January experiences chillier conditions, with temperatures ranging from a minimum of -5°C (24°F) to a maximum of 14°C (58°F), leading to a lower average of 5°C (41°F). January is slightly drier, with 54 mm (2.1 in) of rain over 10 days, but the humidity is notably higher at 91%. For more information, you can check London weather in January.

May typically brings milder and more enjoyable weather compared to February. With average temperatures ranging from a low of 1°C (35°F) to a high of 25°C (78°F), May is warmer, boasting an average of 13°C (55°F). In contrast, February experiences colder temperatures, from a minimum of -5°C (23°F) to a maximum of 18°C (65°F), with an average of 6°C (43°F). Additionally, while May sees an average precipitation of 62 mm (2.5 in) over 11 days, February has slightly less precipitation at 53 mm (2.1 in) over the same number of days. The humidity is also higher in February at 89%, compared to May's 79%. For more details, check out London weather in February.

In comparing the weather of May and March, May generally brings warmer temperatures, with a minimum of 1°C (35°F), an average of 13°C (55°F), and a maximum of 25°C (78°F). In contrast, March has chillier conditions, recording a minimum of -5°C (23°F) and an average of 7°C (46°F), with a maximum of 22°C (71°F). While May sees slightly more rainfall at 62 mm (2.5 in) over 11 days, March has 54 mm (2.1 in) spread over 13 days, indicating a wetter month despite being cooler. Additionally, March experiences a higher humidity level of 86% compared to May's 79%. For more detailed weather information, you can refer to London weather in March.

When comparing the weather in April and May, we see a noticeable shift in both temperature and precipitation. May enjoys a warmer average temperature of 13°C (55°F) compared to April’s 10°C (49°F), with minimum and maximum temperatures hovering between 1°C (35°F) to 25°C (78°F) in May, while April ranges from -2°C (29°F) to 26°C (80°F). Although May is slightly wetter with 62 mm (2.5 in) of precipitation over 11 days, April has a lower total of 33 mm (1.3 in) and fewer rainy days at 8. Additionally, the humidity in April is marginally higher at 85% compared to May’s 79%. For more detailed information, you can check London weather in April.

May and June exhibit notable differences in weather patterns. In May, temperatures range from a chilly minimum of 1°C (35°F) to a pleasant maximum of 25°C (78°F), with an average of 13°C (55°F). The month sees about 62 mm (2.5 in) of precipitation over 11 days, with humidity sitting at 79%. In contrast, June experiences a warmer climate, with temperatures beginning at 7°C (45°F) and peaking at 31°C (89°F), resulting in an average of 16°C (62°F). Although rainfall increases slightly to 77 mm (3.0 in) over just 9 days, humidity remains slightly higher at 80%. For more details on the weather during this month, check out London weather in June.

In comparing the weather of May and July, it is clear that July offers significantly warmer temperatures, with a minimum of 9°C (49°F) and a maximum soaring up to 36°C (96°F), compared to May's more moderate range of 1°C (35°F) to 25°C (78°F). The average temperature rises from 13°C (55°F) in May to 18°C (65°F) in July, making July feel much more summery. Interestingly, both months experience comparable levels of precipitation, around 64 mm (2.5 in) over 11 days, but July's humidity is slightly lower at 71%, versus May's 79%. For a detailed look at July's climate, check out London weather in July.

May and August offer distinctly different weather experiences. In May, temperatures range from a chilly 1°C (35°F) at night to a pleasant 25°C (78°F) during the day, with an average temperature around 13°C (55°F). The month sees about 62 mm (2.5 in) of precipitation over 11 days, accompanied by a relatively high humidity of 79%. In contrast, August boasts a milder nighttime low of 8°C (47°F) and can reach up to a sweltering 34°C (93°F), averaging 18°C (64°F). Although August has slightly more precipitation at 70 mm (2.7 in) over 12 days, its humidity is slightly lower at 76%. For more details on the August climate, check out London weather in August.

May and September offer distinct weather experiences, with May starting off cooler and gradually warming up, while September showcases a mild transition into autumn. In May, temperatures range from a chilly minimum of 1°C (35°F) to a comfortable maximum of 25°C (78°F), with an average of 13°C (55°F). The month sees about 62 mm (2.5 in) of precipitation over 11 days, contributing to a humidity level of 79%. In contrast, September presents slightly warmer conditions with minimum temperatures of 4°C (39°F) and maximums reaching 28°C (83°F), averaging 15°C (59°F). It is also drier, with only 45 mm (1.8 in) of rain falling over 10 days, leading to a marginally higher humidity of 82%. For a more detailed look at September's climate, check out London weather in September.

May and October offer distinct weather experiences. In May, temperatures range from a minimum of 1°C (35°F) to a pleasant average of 13°C (55°F), peaking at 25°C (78°F). The month enjoys an average of 62 mm (2.5 in) of precipitation over 11 days, with humidity at 79%. In contrast, October sees slightly cooler conditions with temperatures ranging from 1°C (34°F) to an average of 12°C (54°F) and a maximum of 22°C (73°F). Precipitation increases to 84 mm (3.3 in) across 12 days, accompanied by higher humidity levels at 90%. For more details, you can check London weather in October.

May and November present contrasting weather patterns, reflective of the transition from spring to late autumn. In May, temperatures range from a minimum of 1°C (35°F) to a pleasant average of 13°C (55°F), peaking at 25°C (78°F), making it generally warmer and more vibrant. The month also sees an average precipitation of 62 mm (2.5 in) over 11 days, coupled with a humidity level of 79%. In stark contrast, November experiences cooler temperatures, with a minimum of -2°C (29°F) and an average of 8°C (47°F), reaching a maximum of just 16°C (62°F). Despite slightly lower precipitation at 52 mm (2.0 in) across the same number of days, the humidity is notably higher at 92%, contributing to a damp and chilly atmosphere. For a more detailed look at November weather, you can explore London weather in November.

May and December present contrasting weather conditions. In May, temperatures range from a minimum of 1°C (35°F) to a pleasant maximum of 25°C (78°F), with an average of 13°C (55°F). The month experiences 62 mm (2.5 in) of precipitation spread over 11 days, accompanied by a humidity level of 79%. In contrast, December brings much colder temperatures, with a low of -4°C (24°F) and a high of only 14°C (58°F), averaging around 6°C (44°F). This winter month is wetter, seeing 84 mm (3.3 in) of rain over 13 days, and a higher humidity of 92%. For more insights on December weather, check out London weather in December.

Compare London's Climate with Cities Worldwide

Conclusion: What to Expect From May Weather in London

As May unfolds in London, the city's weather begins to transition, bringing a breath of warmth that stands in contrast to the lingering chill of early spring. With temperatures gradually rising, it's a promising time for outdoor activities, albeit accompanied by a touch of unpredictability in rainfall and humidity. The month sees an increase in both sun and showers, creating a varied palette of weather that keeps residents and visitors alike on their toes. Overall, May serves as a vibrant prelude to summer, striking a delicate balance between cool evenings and pleasant daytime warmth, making it an exceptional time to explore the city's charm. To learn more about how this month compares to others, check out London Climate.