May Weather in Wales, United Kingdom

Last updated: March 17, 2025

May in Wales, United Kingdom, offers a delightful blend of mild weather and occasional rain. With maximum temperatures reaching up to 25°C (78°F) and an average of 12°C (53°F), the month showcases the region's gradual transition into summer. However, visitors should be prepared for a typical Welsh welcome, as precipitation occurs on 13 days, accumulating to 64 mm (2.5 in) throughout the month. Coupled with an average humidity level of 80%, the atmosphere can feel quite refreshing, making it an ideal time for exploring Wales' stunning landscapes and vibrant flora.

May Temperature in Wales

In May, temperatures in Wales, United Kingdom begin to showcase the charm of spring fully unfolding, with a minimum temperature of 0°C (32°F) and an average of 12°C (53°F). As the month progresses, the maximum temperature can reach an inviting 25°C (78°F), hinting at the warm days of summer ahead. This pattern marks a notable climb from the colder, winter months, reflecting a transition from the chilly lows of January and February, where temperatures dip below freezing. The increase in warmth in May not only fosters a vibrant natural landscape but also enhances outdoor activities, making it an ideal time to explore the scenic beauty of Wales.

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

The chart illustrates May temperature patterns in Wales, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends.
JanFebMarAprMayJunJulAugSepOctNovDec404144475359636257524542
Data source: Temperature data for Wales 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 Wales

May in Wales typically brings a welcomed balance of spring warmth and notable precipitation, with averages of 64 mm (2.5 in) falling over 13 days of the month. This amount sits comfortably between the drier April, which saw only 40 mm of rain, and the heavier June, which tends to bring 80 mm. The uptick in rainfall compared to April is indicative of Wales’ transition into the lush greenery of early summer. As temperatures rise, the showers of May contribute to the vibrant landscapes Wales is renowned for, setting the stage for a rich and inviting summer ahead.

May Precipitation Trends in Wales

The chart displays monthly precipitation patterns in Wales, 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.
JanFebMarAprMayJunJulAugSepOctNovDec516768406480807763826580
Data source: Precipitation data for May generated using information from the Copernicus Climate Change Service.
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May Humidity in Wales

In May, Wales experiences a noticeable shift in humidity, dropping to 80% from the higher levels of preceding months. This decline marks the beginning of a trend that continues into the warmer months, with June rising slightly to 81%, and then a more significant decrease in July to 76%. As spring transitions into summer, the overall humidity staves off the oppressive heat, providing a more comfortable atmosphere for both residents and visitors. Following this dip, humidity begins to climb again in late summer and autumn, reaching peaks of 85% in September and returning to 90% by October. This cyclical pattern underscores Wales' characteristic maritime climate, where humidity levels are markedly high in winter and autumn, yet allow for a breath of fresh air during the early summer months.

May Average Humidity in Wales

This chart illustrates the average monthly humidity levels in Wales, 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.
JanFebMarAprMayJunJulAugSepOctNovDec90%88%86%84%80%81%76%77%85%90%92%90%
Data source: Humidity data for May generated using information from the Copernicus Climate Change Service.

May UV Index in Wales

As May approaches in Wales, the UV Index sees a significant jump to 7, marking a shift into the high exposure category. This increase reflects the warmer weather and longer days, with a reduced burn time of just 25 minutes for those with fair skin. Compared to the preceding months, where the Index climbed steadily from 1 in January to 5 in April, May signals the start of stronger sun protection measures. By understanding this trend, individuals can enjoy the emerging sunshine while staying safe. For further insights on UV levels throughout the year, visit Wales UV Index.

Maximum UV Index Levels in Wales for May

The chart shows the monthly maximum UV Index (UVI) for Wales 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.
JanFebMarAprMayJunJulAugSepOctNovDec124578875421
Data source: Wales 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 Wales

May shines brightly in Wales, boasting an impressive 380 hours of sunshine, making it one of the sunniest months of the year. This peak follows a significant gradual increase from the 81 hours in January and a vibrant 313 hours in April, highlighting spring's transition to summer. The warm embrace of May serves as a delightful prelude to the sunshine that continues through June and July, albeit slightly reduced, with 344 and 375 hours respectively. As summer fades into autumn, the sunshine hours gradually decline, yet May remains a cherished milestone, celebrated for its lively days and the blooming beauty of the Welsh landscape.

Monthly Sunshine Duration in Wales: May Highlighted

The May sunshine duration represents the total number of hours Wales 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.
JanFebMarAprMayJunJulAugSepOctNovDec81h144h194h313h380h344h375h351h277h223h123h96h
Data source: Wales May Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Wales During May

As May rolls around in Wales, the probability of sunny weather stands at 30%, which contrasts with the significant 46% chance seen in April. This slight dip reflects a transition as spring gives way to early summer, where June presents a 28% likelihood of sunshine. Interestingly, while May's sunshine chances are not as robust as its predecessor, they still outperform several months throughout the year, like January and February, which struggle to break the 25% mark. Thus, while May may not be the sunniest month, it offers a decent shot at enjoying pleasant weather, making it a time for outdoor activities and vibrant spring blooms.

Percentage of Sunny Days in May in Wales

The chart illustrates the percentage of sunny days in Wales 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 Wales experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec21%25%25%46%30%28%35%22%29%22%30%20%
Data source: Wales May chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Wales in May

As spring blossoms into summer, the daylight duration in Wales showcases a remarkable transformation. Starting with a modest 8 hours in January, the days gradually lengthen through February and March, reaching 14 hours by April. May peaks with 15 hours of daylight, allowing for ample time to indulge in outdoor activities and bask in the increasing warmth. June and July maintain this bright momentum with 16 hours of daylight, creating a vibrant atmosphere perfect for exploring the lush Welsh landscapes. However, as summer wanes in August, daylight begins a gentle decline, settling at 14 hours before transitioning to shorter days in September and October, ultimately returning to 8 hours by November. This clear trend underscores the dynamic nature of daylight in Wales, inviting residents and visitors alike to embrace the bright months while they last.

Average Daylight Hours in Wales for May

The chart illustrates the variation in daylight duration in Wales throughout the year, with May highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec8h 8m9h 50m11h 54m14h 1m15h 53m16h 52m16h 21m14h 40m12h 37m10h 30m8h 36m7h 35m
Data source: Wales daylight hours, calculated by summing the hours between sunrise and sunset for each day.

May Winds in Wales

In May, Wales experiences a moderate average wind speed of 3.9 m/s (9 mph), marking a slight uptick from the calmer, breezier months of April. This gentle gustiness creates a refreshing atmosphere as spring unfolds, contrasting with the stronger winds seen in the early and late months of the year, such as 5.3 m/s (12 mph) in October and 4.5 m/s (10 mph) in January. Following the trend of fluctuating wind speeds, May offers a transition towards the more consistent breezes of late spring and summer, while still being less blustery than the preceding spring months. As summer approaches, Wales retains its charm, with just a hint of wind to accompany the vibrant greenery and blossoming landscapes, inviting both residents and visitors to revel in the beauty of this picturesque region.

Average May Wind Speed in Wales

The chart displays monthly wind speed patterns in Wales, 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.
JanFebMarAprMayJunJulAugSepOctNovDec4.55.04.83.33.9 m/s3.32.93.93.65.34.84.6
Data source: Wales May wind data, generated using information from the Copernicus Climate Change Service.

How May Weather in Wales Compares to Other Months

The weather in Wales 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 Wales and find detailed weather information for every month.

May and January present distinctly different weather patterns. In May, temperatures start to rise, ranging from a chilly minimum of 0°C (32°F) to a pleasant maximum of 25°C (78°F), with an average of 12°C (53°F). The month sees about 64 mm (2.5 in) of precipitation over 13 days, accompanied by relatively high humidity at 80%. In contrast, January is much colder, with temperatures dipping as low as -4°C (24°F) and peaking at only 14°C (58°F), averaging around 5°C (40°F). While January has slightly less rainfall at 51 mm (2.0 in) over 10 days, it experiences a higher humidity level at 90%. For more details on January weather, you can check out Wales weather in January.

When comparing the weather in May and February, notable differences emerge. May typically experiences milder temperatures, ranging from a minimum of 0°C (32°F) to a maximum of 25°C (78°F), while February can be quite chilly, with temperatures dropping as low as -5°C (23°F) and peaking at 17°C (63°F). Precipitation is relatively similar in both months, with May receiving 64 mm (2.5 in) over 13 days and February slightly higher at 67 mm (2.6 in) over 12 days. Additionally, humidity levels are more pronounced in February at 88%, compared to 80% in May. For more detailed information about February weather, you can check Wales weather in February.

When comparing the weather in May and March, it's evident that May tends to be milder and warmer. In May, temperatures range from a minimum of 0°C (32°F) to a maximum of 25°C (78°F), with an average of 12°C (53°F). In contrast, March experiences a broader temperature range with a minimum of -7°C (20°F) and a maximum of 20°C (68°F), averaging at 7°C (44°F). Both months see a similar amount of precipitation, with March receiving slightly more at 68 mm (2.7 in) compared to May's 64 mm (2.5 in), but March also has higher humidity at 86% compared to May's 80%. For more detailed information on March weather in Wales, you can check Wales weather in March.

In comparing the weather between April and May, we can see notable differences in both temperature and precipitation. April experiences slightly cooler temperatures, with a minimum of -2°C (28°F) and an average of 8°C (47°F), while May offers a warmer minimum of 0°C (32°F) and a higher average of 12°C (53°F). Both months peak at a maximum of 25°C (77°F) but May is generally more humid at 80% compared to April's 84%. When it comes to precipitation, April has less rainfall at 40 mm (1.6 in) over 7 days, whereas May sees an increase to 64 mm (2.5 in) over 13 days. For a more detailed look at April's weather, visit Wales weather in April.

May and June both exhibit pleasant weather, but June tends to be warmer and slightly wetter. In May, temperatures range from a chilly 0°C (32°F) to a mild 25°C (78°F), with an average of 12°C (53°F). The month experiences around 64 mm (2.5 in) of precipitation over 13 days and maintains a humidity level of 80%. In contrast, June sees minimum temperatures of 6°C (43°F) and maximums reaching 29°C (84°F), with an average of 15°C (59°F). Although June has slightly higher precipitation at 80 mm (3.1 in) over the same number of days, the humidity remains relatively constant at 81%. For more detailed weather insights, visit Wales weather in June.

In May, temperatures range from a chilly 0°C (32°F) at night to a comfortable high of 25°C (78°F) during the day, with an average temperature of 12°C (53°F). The month experiences about 64 mm (2.5 in) of precipitation spread over 13 days, accompanied by relatively high humidity at 80%. In contrast, July brings warmer weather with minimum temperatures starting at 7°C (45°F) and reaching a sweltering maximum of 35°C (95°F), averaging 17°C (63°F). July sees a slight increase in precipitation, totaling 80 mm (3.1 in) over 12 days, but the humidity drops to a more manageable 76%. For more details on weather patterns, check out Wales weather in July.

May typically showcases cooler temperatures, with averages around 12°C (53°F) and a maximum of 25°C (78°F), while August enjoys a warmer climate with an average of 16°C (62°F) and peaks reaching up to 32°C (90°F). Precipitation is slightly higher in August at 77 mm (3.0 in), compared to May's 64 mm (2.5 in), although the number of rainy days is nearly the same, with May experiencing rain on 13 days and August on 12. Humidity levels are also comparable, with May averaging 80% and August just a bit lower at 77%. For more details on the August weather in Wales, you can visit Wales weather in August.

May and September offer distinct yet mild weather patterns, perfect for enjoying outdoor activities. In May, temperatures range from a cool 0°C (32°F) at night to a pleasant 25°C (78°F) during the day, with an average of 12°C (53°F). The month experiences around 64 mm (2.5 in) of precipitation, spread across 13 days, and humidity levels hover around 80%.

In contrast, September sees slightly warmer temperatures, with a minimum of 4°C (39°F) and a maximum of 28°C (83°F), averaging 14°C (57°F). Precipitation is similar at 63 mm (2.5 in) but occurs over fewer days, with rain expected on just 11 days. The humidity is a bit higher at 85%, contributing to a lush late summer ambiance. For a closer look at September weather, check out Wales weather in September.

When comparing the weather in May and October, we see some notable differences. May typically offers a warmer overall temperature range, with average highs reaching up to 25°C (78°F) compared to October's average maximum of 23°C (73°F). However, October brings a higher level of precipitation, with 82 mm (3.2 in) falling over 14 days, whereas May experiences 64 mm (2.5 in) over 13 days. Additionally, October is slightly more humid, with levels at 90% compared to May's 80%. For more detailed insights into October weather patterns, you can explore Wales weather in October.

May and November present distinctly different weather patterns. In May, temperatures range from a minimum of 0°C (32°F) to a pleasant maximum of 25°C (78°F), with an average of 12°C (53°F). This month experiences about 64 mm (2.5 in) of precipitation over 13 days, and humidity levels hover around 80%. In contrast, November sees colder weather, with temperatures dipping as low as -4°C (26°F) and a maximum of 17°C (63°F), averaging at 7°C (45°F). The precipitation levels are similar at 65 mm (2.5 in) across 12 days, but the humidity rises to a higher 92%. For more details about the weather in November, check out Wales weather in November.

In comparing the weather of May and December, we see notable differences in temperature and precipitation. May typically experiences milder conditions with minimum temperatures around 0°C (32°F) and an average of 12°C (53°F), reaching a maximum of 25°C (78°F). In contrast, December is significantly colder, with minimum temperatures dipping to -3°C (27°F) and an average of just 5°C (42°F), peaking at 14°C (58°F). Moreover, while May sees about 64 mm (2.5 in) of precipitation over 13 days, December is slightly wetter with 80 mm (3.1 in) spread across 15 days, accompanied by higher humidity levels of 90%. For more information on December weather specifics, you can visit Wales weather in December.

Compare Wales's Climate with Cities Worldwide

Conclusion: What to Expect From May Weather in Wales

May in Wales heralds the arrival of spring with its mild temperatures and blossoming landscapes, offering a welcome contrast to the chill of earlier months. While the average temperature of 12°C (53°F) invites outdoor explorations, occasional highs of 25°C (78°F) remind us of warmer days ahead. However, don’t forget to pack an umbrella; with about 64 mm (2.5 in) of precipitation over 13 days, rain can make an appearance. The humidity at 80% can create a refreshing yet damp feel, typical of Welsh weather. As May unfolds, visitors can enjoy a vibrant tapestry of nature awakening, offering glimpses of what summer has in store. To learn more about the broader climate patterns in this beautiful region, visit Wales Climate.