May Weather in Swansea, United Kingdom

Last updated: March 17, 2025

May in Swansea, United Kingdom, presents a refreshing mix of springtime warmth and occasional showers. With a maximum temperature reaching 21°C (70°F) and an average of 12°C (53°F), this month invites outdoor activities amidst the changing scenery. However, be prepared for the cooler minimum of 5°C (40°F) during the chillier nights. Rainfall is a common companion, totaling 79 mm (3.1 in) over 11 days, contributing to the region's lush greenery. With a humidity level hovering around 80%, the air is often crisp, creating an invigorating atmosphere for both locals and visitors alike. Embrace the vibrant spirit of Swansea this May!

May Temperature in Swansea

In May, Swansea begins to shake off the lingering chill of spring, with temperatures gradually rising as the month progresses. The minimum temperature settles at a mild 5°C (40°F), while pleasant days see averages of around 12°C (53°F) and peaks reaching a comfortable 21°C (70°F). This notable warmth marks a significant shift from the cooler months of January through April, where highs barely reached the mid-teens. As May unfolds, the vibrant city embraces longer, sunnier days, inviting residents and visitors alike to enjoy the blossoming landscapes and outdoor festivities that herald the arrival of summer.

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

The chart illustrates May 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.
JanFebMarAprMayJunJulAugSepOctNovDec444546495359626259555047
Data source: Temperature data for Swansea generated using information from the Copernicus Climate Change Service.
Choose your preferred temperature unit
The average of daily temperatures (24 hours) calculated across all days in the month.

May Precipitation in Swansea

In May, Swansea experiences a moderate increase in precipitation, accumulating 79 mm (3.1 in) over 11 days. This amount reflects a noticeable recovery from the dry spell of April, which recorded only 56 mm (2.2 in) across 9 days. Although May's rainfall is less than the preceding months, it sets the stage for the wetter summer months ahead. The overall trend suggests a gradual rise in precipitation leading into the summer, impacting the lush greenery that characterizes the region. As the temperature warms, May serves as a bridge, transitioning from the milder spring rains to the heavier downpours of June and beyond.

May Precipitation Trends in Swansea

The chart displays monthly precipitation patterns in Swansea, 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.
JanFebMarAprMayJunJulAugSepOctNovDec10612811456809391123120184143184
Data source: Precipitation data for May generated using information from the Copernicus Climate Change Service.
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May Humidity in Swansea

In Swansea, May marks a notable shift in humidity as levels drop to 80%, providing a breath of fresh air compared to the earlier months of the year. While January and February linger at a high 88%, and March and April gradually decrease to 86% and 84% respectively, May signals the start of a more temperate atmosphere. This reduction in humidity continues into June with a stable 80%, hinting at a more pleasant and inviting environment as summer approaches. Overall, May's humidity reflects a positive trend towards drier conditions, paving the way for the warm and enjoyable months ahead.

May Average Humidity in Swansea

This chart illustrates the average monthly humidity levels in Swansea, 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.
JanFebMarAprMayJunJulAugSepOctNovDec89%88%86%84%80%80%70%73%79%89%90%89%
Data source: Humidity data for May generated using information from the Copernicus Climate Change Service.

May UV Index in Swansea

As May rolls into Swansea, the UV Index spikes to 7, marking a shift into the high exposure category and a burn time of just 25 minutes. This trend reflects the increasing intensity of the sun as spring transitions towards summer, with the May UV level remaining higher than the previous months like April’s 6 and significantly more pronounced than the winter months where UV exposure was low. The rise in the UV Index underlines the importance of sun protection during this time, as both locals and visitors enjoy the warming weather. Moreover, the upward trajectory continues into June, where the UV Index reaches 8, emphasizing the need for vigilance in sun safety. For more detailed information on UV levels and recommendations, check out Swansea UV Index.

Maximum UV Index Levels in Swansea for May

The chart shows the monthly maximum UV Index (UVI) for Swansea 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.
JanFebMarAprMayJunJulAugSepOctNovDec124678876421
Data source: Swansea 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 Swansea

As spring unfolds into summer in Swansea, May stands out with an impressive 404 hours of sunshine, marking a delightful peak in the city's sunlight hours. This month not only showcases a significant surge from April's 333 hours but also sets the tone for the vibrant summer months ahead. June and July, while still basking in generous sunlight with 391 and 418 hours respectively, see a gradual decline following May's splendour. Interestingly, the trend displays a consistent escalation from the bleak winter months, where January recorded a mere 93 hours, culminating in May's sun-kissed glory. As Swansea transitions into late summer and autumn, the sunshine hours contract, but the joy infused during May lingers in residents' memories, reminding them of the bright days ahead.

Monthly Sunshine Duration in Swansea: May Highlighted

The May sunshine duration represents the total number of hours Swansea 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.
JanFebMarAprMayJunJulAugSepOctNovDec93h151h219h333h404h391h418h374h309h241h135h110h
Data source: Swansea May Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Swansea During May

May in Swansea offers a moderate chance of sunny weather, with around 35% likelihood of sunshine. This marks a slight decline from the more promising 56% in April, suggesting that while early spring may bask in brighter skies, May's sunshine can be somewhat unpredictable. As we transition from spring to early summer, the weather shifts again, with June experiencing a further drop to 27% chance of sun. This trend highlights how Swansea's climate can be quite variable, making it essential for locals and visitors alike to prepare for an array of weather conditions throughout the month.

Percentage of Sunny Days in May in Swansea

The chart illustrates the percentage of sunny days in Swansea 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 Swansea experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec24%25%31%56%35%27%42%35%29%22%27%22%
Data source: Swansea May chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Swansea in May

As spring gracefully transitions into summer, May emerges as a month of abundant daylight in Swansea, with 15 hours of sunlight gracing the skies. This surge marks a noticeable increase from the 13 hours experienced in April, reflecting the longer days that characterize the late spring season. As nature comes alive, the extended daylight not only encourages outdoor activities but also enhances the vibrant atmosphere of the city. Following May, daylight peaks in June at 16 hours, before gradually tapering off into the warmer months of summer and toward autumn. The clear trend of lengthening days throughout spring underscores the region's seasonal transformation, inviting both residents and visitors alike to savor the beauty of longer, brighter evenings.

Average Daylight Hours in Swansea for May

The chart illustrates the variation in daylight duration in Swansea 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: Swansea daylight hours, calculated by summing the hours between sunrise and sunset for each day.

May Winds in Swansea

In Swansea, the wind begins to shift as spring transitions into summer, with May showcasing an average wind speed of 5.8 m/s (13 mph). This moderate breeze offers a refreshing respite compared to the gusts seen earlier in the year, particularly January and February, which recorded higher speeds of 6.5 m/s (15 mph) and 7.4 m/s (17 mph), respectively. As temperatures rise, the winds gradually soften, culminating in the gentle 4.1 m/s (9 mph) observed in both June and July. This trend underscores a seasonal pattern where spring heralds slightly stronger winds before the summer months bring calmness, encouraging outdoor activities in Swansea’s beautiful coastal setting.

Average May Wind Speed in Swansea

The chart displays monthly wind speed patterns in Swansea, 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.
JanFebMarAprMayJunJulAugSepOctNovDec6.57.46.24.75.8 m/s4.14.15.24.76.65.77.3
Data source: Swansea May wind data, generated using information from the Copernicus Climate Change Service.

How May Weather in Swansea Compares to Other Months

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

May and January present distinctly different weather patterns. In May, temperatures range from a minimum of 5°C (40°F) to a pleasant maximum of 21°C (70°F), with an average of 12°C (53°F). The month sees about 79 mm (3.1 in) of precipitation over approximately 11 days, accompanied by a humidity level of 80%. In contrast, January is cooler, with temperatures ranging from 0°C (32°F) to a maximum of 14°C (57°F), resulting in an average of 7°C (45°F). It experiences slightly higher precipitation at 106 mm (4.2 in) over 14 days, and humidity is a touch higher at 88%. For more detailed insights, you can visit Swansea weather in January.

In comparing the weather between May and February, we see a noticeable shift in both temperature and precipitation. May generally enjoys milder temperatures, with a minimum of 5°C (40°F) and a maximum of 21°C (70°F), whereas February can be quite chilly, marked by a minimum of -1°C (30°F) and a maximum of 13°C (55°F). While May experiences about 79 mm (3.1 inches) of precipitation over 11 days, February sees higher precipitation levels at 128 mm (5.0 inches) spread across 17 days. Additionally, humidity is slightly higher in February at 88%, compared to May's 80%. For more detailed insights on February weather, you can refer to Swansea weather in February.

In comparing the weather between March and May, it's clear that May experiences milder temperatures, with a minimum of 5°C (40°F) and an average of 12°C (53°F), compared to March's colder minimum of -4°C (25°F) and average of 8°C (46°F). May also boasts warmer maximum temperatures, reaching up to 21°C (70°F), while March peaks at 15°C (59°F). However, March has higher precipitation levels, accumulating 114 mm (4.5 in) over 18 days, compared to May's 79 mm (3.1 in) across 11 days. Additionally, March tends to be slightly more humid at 86%, compared to May's 80%. For more detailed insights, check out Swansea weather in March.

In comparing the weather between April and May, it is clear that May tends to be warmer, with average temperatures rising from 9°C (49°F) in April to 12°C (53°F). The maximum temperature in May reaches 21°C (70°F), which is significantly higher than April's maximum of 17°C (63°F). However, May also experiences more precipitation, with 79 mm (3.1 in) over 11 days compared to April's 56 mm (2.2 in) over 9 days. Humidity levels are slightly lower in May at 80%, compared to April's 84%. For more details on April weather, visit Swansea weather in April.

In comparison, May generally presents cooler temperatures than June, with an average of 12°C (53°F) and a maximum of 21°C (70°F) in May, contrasted with June's higher average of 15°C (59°F) and max of 24°C (76°F). Both months experience similar humidity levels at 80%, but June sees slightly more precipitation, measuring 93 mm (3.6 in) over 15 days compared to May’s 79 mm (3.1 in) over 11 days. This trend suggests that as spring transitions into summer, temperatures rise while the likelihood of rain remains relatively consistent. For more details about June's weather, you can check Swansea weather in June.

In comparison to May, July experiences warmer temperatures, with minimums rising from 5°C (40°F) to 11°C (52°F) and average highs increasing from 21°C (70°F) to 24°C (76°F). While May is characterized by a higher average humidity of 80%, July's humidity sits at a more comfortable 70%. Precipitation levels are slightly elevated in July, with 91 mm (3.6 in) falling over 13 days compared to May's 79 mm (3.1 in) over 11 days. For more details on July weather, you can check this link: Swansea weather in July.

May and August present contrasting weather patterns, reflecting the transition from spring to summer. In May, temperatures range from a minimum of 5°C (40°F) to a maximum of 21°C (70°F), with an average temperature of 12°C (53°F). The month is relatively wet, with 79 mm (3.1 in) of precipitation over approximately 11 days and a high humidity level of 80%. Conversely, August offers warmer conditions, with temperatures ranging from 12°C (53°F) to 24°C (75°F) and an average of 17°C (62°F). However, it is also wetter, receiving 123 mm (4.8 in) of rainfall over about 18 days, though humidity decreases to 73%. For more details on August's weather, visit Swansea weather in August.

In May, temperatures in Swansea range from a minimum of 5°C (40°F) to a maximum of 21°C (70°F), with an average of 12°C (53°F). The month typically experiences about 79 mm (3.1 in) of rainfall spread over 11 days, accompanied by a humidity level of 80%. In contrast, September sees warmer temperatures, with a minimum of 9°C (48°F) and a maximum of 24°C (76°F), averaging 15°C (60°F). However, it also brings more rain, with approximately 120 mm (4.7 in) falling over 15 rainy days, while the humidity remains relatively stable at 79%. For more detailed insights, you can check Swansea weather in September.

When comparing May and October weather, we notice some distinct differences. May typically features milder temperatures, with a minimum of 5°C (40°F) and an average of 12°C (53°F), while October starts cooler, with a minimum of 3°C (38°F) and an average of 13°C (55°F). Precipitation levels are considerably higher in October, with 184 mm (7.2 in) falling over 19 days compared to May's 79 mm (3.1 in) over 11 days. Additionally, October experiences a higher humidity level at 89%, compared to May's 80%. For further details on October conditions, you can check out Swansea weather in October.

May typically experiences milder temperatures with averages around 12°C (53°F), peaking at a pleasant 21°C (70°F), while November's temperatures are noticeably cooler, averaging just 10°C (50°F) and reaching a maximum of 16°C (60°F). In terms of rainfall, May sees lighter precipitation at 79 mm (3.1 in) over about 11 days, whereas November is much wetter with 143 mm (5.6 in) falling across 19 days. Additionally, humidity levels are slightly higher in November at 90% compared to May's 80%, contributing to a more overcast and potentially damp atmosphere. For more detailed insights, check out Swansea weather in November.

In May, temperatures gradually warm up with a minimum of 5°C (40°F) and an average high of 21°C (70°F), making it feel quite pleasant. The month sees moderate rainfall, with about 79 mm (3.1 in) spread over approximately 11 days, and humidity levels are relatively comfortable at around 80%. In contrast, December brings much cooler weather, with temperatures ranging from a low of 2°C (35°F) to a high of only 13°C (55°F). This month is characterized by significantly higher precipitation, totaling 184 mm (7.3 in) over about 21 days, and increased humidity at 89%. For more detailed information, you can check Swansea weather in December.

Compare Swansea's Climate with Cities Worldwide

Conclusion: What to Expect From May Weather in Swansea

As May ushers in the bloom of spring in Swansea, the weather brings a refreshing change compared to the colder months. With temperatures gradually rising, days become more pleasant, though cool evenings remind us that summer is just around the corner. This month sees a notable increase in humidity and a slight uptick in rainfall, with approximately 11 days experiencing precipitation, making it essential to carry an umbrella. While May may still bring some overcast skies, the overall ambiance is vibrant, setting the stage for outdoor activities and exploration. To better understand the unique characteristics of Swansea's climate throughout the year, be sure to check out Swansea Climate.