May Weather in Castletown, Isle of Man

Last updated: August 21, 2025

May in Castletown, Isle of Man brings a gentle embrace of springtime weather, characterized by a maximum temperature reaching 16°C (60°F) and an average of 10°C (51°F). With minimum temperatures dipping to 5°C (42°F), residents and visitors can expect a mild climate, albeit accompanied by 79% humidity that adds a fresh feel to the air. Rainfall is moderate, with a total precipitation amount of 44 mm (1.7 in) spread across 9 days, providing vital moisture to the lush landscapes. This vibrant month offers a delightful backdrop for outdoor activities, inviting exploration of the scenic beauty that the Isle of Man has to offer.

May Temperature in Castletown

In May, Castletown, Isle of Man, experiences a delightful transition into spring as temperatures begin to warm up noticeably. With minimums averaging 5°C (42°F) and maximums reaching 16°C (60°F), May marks a significant increase from the chill of earlier months. The average temperature climbs to 10°C (51°F), hinting at brighter days and more outdoor activities. This month stands out as part of a clear upward trend, where the weather begins to mirror the lush beauty of the island, making it an ideal time for visitors and locals alike to explore the scenic landscapes as nature awakens. The incremental rise from the preceding April offers a reassuring promise of a stretch of milder weather ahead.

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

The chart illustrates May temperature patterns in Castletown, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Castletown, May typically has an average temperature of {2}°C ({3}°F), with highs reaching up to {4}°C ({5}°F) and lows dropping to around {6}°C ({7}°F).
JanFebMarAprMayJunJulAugSepOctNovDec464545475155585958555047
Data source: Temperature data for Castletown 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 Castletown

May in Castletown, Isle of Man, sees a moderate precipitation total of 44 mm (1.7 in) spread over nine days, marking a slight uptick from the driest month of April, which recorded only 36 mm. This trend illustrates the transition into late spring, where the weather begins to shift, paving the way for the wetter summer months ahead. In comparison to the earlier months, May tends to offer a more balanced mix of dry spells and refreshing showers, providing a vibrant backdrop for the island's blooming flora. As the year progresses, precipitation levels generally rise, peaking in the autumn months, making May a quaint interlude before the heavier rains return.

May Precipitation Trends in Castletown

The chart displays monthly precipitation patterns in Castletown, 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 Castletown, May typically receives around {2} mm ({3} inches) of precipitation spread over approximately {4} days.
JanFebMarAprMayJunJulAugSepOctNovDec8110687364470709492142144144
Data source: Precipitation data for May generated using information from the Copernicus Climate Change Service.
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May Humidity in Castletown

As May greets Castletown, Isle of Man, humidity levels dip to 79%, marking a slight but significant shift from the wetter months of winter and early spring. This reduction follows a consistent trend of decreasing humidity from January through April, where levels hovered around the high 80s and low 90s. Interestingly, this refreshing decline brings a sense of respite just before the summer months roll in, when humidity begins to rise again in June. With May acting as a transitional period, the more moderate atmosphere offers an ideal backdrop for enjoying the island's lush landscapes before the humidity creeps back up during the peak summer months.

May Average Humidity in Castletown

This chart illustrates the average monthly humidity levels in Castletown, 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 Castletown is approximately {2}%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec89%88%86%85%79%81%78%79%85%90%91%89%
Data source: Humidity data for May generated using information from the Copernicus Climate Change Service.

May UV Index in Castletown

As spring transitions into summer, May brings a notable increase in UV intensity in Castletown, Isle of Man, with the UV Index rising to 7, categorized as high. This marks a significant shift from the more moderate levels observed in the preceding months, where UV exposure was relatively low. With a burn time of just 25 minutes, it's essential for sun-seekers to be vigilant about protection during this month. This trend is consistent with the general progression into summer, where UV levels in June and July reach even higher peaks, highlighting the need for sun safety as summer approaches. Stay informed and plan your outdoor activities accordingly by checking the detailed UV forecast here: Castletown UV Index.

Maximum UV Index Levels in Castletown for May

The chart shows the monthly maximum UV Index (UVI) for Castletown 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 Castletown typically reaches {2}, which falls under the {3} exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec123578875321
Data source: Castletown 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 Castletown

May brings a vibrant burst of sunshine to Castletown, Isle of Man, with 418 hours of sunlight—an impressive peak that marks a significant transition from the dreary winter months. As the year progresses, the trend of increasing daylight becomes strikingly evident; January's mere 90 hours gradually gives way to a joyful 341 hours in April. The arrival of May signals not just more hours of sun, but a palpable shift towards summer, with July and August mirroring May’s effulgence at 418 hours each. Following this radiant period, the daylight hours gradually taper off as the year draws to a close, with November and December dipping down to just 131 and 104 hours respectively. This rhythmic ebb and flow of sunshine encapsulates the enchanting charm of Castletown throughout the year, culminating beautifully in the delightful embrace of May.

Monthly Sunshine Duration in Castletown: May Highlighted

The May sunshine duration represents the total number of hours Castletown 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.
JanFebMarAprMayJunJulAugSepOctNovDec90h161h233h341h418h411h418h376h314h244h131h104h
Data source: Castletown May Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Castletown During May

May brings a modest 40% chance of sunny weather to Castletown, Isle of Man, marking a noticeable increase compared to the preceding months. After a relatively gray start to the year, April's sunnier 52% chance sets the tone for a brighter May. However, this peak in sunlight begins to wane over the summer months, as percentages drop again in June and August to 29%. Overall, while May may not be the sunniest month of the year, it certainly offers a promising outlook for those seeking to enjoy a bit more sunshine before the summer season fully unfolds.

Percentage of Sunny Days in May in Castletown

The chart illustrates the percentage of sunny days in Castletown 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 Castletown experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec28%26%25%52%40%29%40%29%24%22%22%21%
Data source: Castletown May chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Castletown in May

As spring blossoms into summer in Castletown, Isle of Man, daylight duration dramatically increases, culminating in May with 16 hours of sunlight. This marks a significant leap from the 14 hours seen in April, reflecting the vibrant transition of the season. Following the upward trend, June reaches its peak with 17 hours, providing a brilliant backdrop for outdoor activities. After May, the days gradually shorten, with July retaining a generous 16 hours, before tapering off as autumn approaches. This progression not only enriches the experience of long, sunlit days but also highlights the playful ebb and flow of daylight throughout the year.

Average Daylight Hours in Castletown for May

The chart illustrates the variation in daylight duration in Castletown throughout the year, with May highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec8h9h 46m11h 54m14h 5m16h 1m17h 2m16h 29m14h 45m12h 38m10h 28m8h 30m7h 26m
Data source: Castletown daylight hours, calculated by summing the hours between sunrise and sunset for each day.

May Winds in Castletown

In Castletown, Isle of Man, May welcomes a gentle shift in the breeze, with an average wind speed of 6.4 m/s (14 mph). This marks a modest increase from the previous month, suggesting a transition from the quieter winds of April, which averaged 5.8 m/s (13 mph). As spring deepens, the winds remain relatively mild compared to the gusts that characterize the winter months, with January and February peaking at 8.5 m/s (19 mph) and 10.5 m/s (24 mph) respectively. With summer approaching, May's breezy charm is set to continue, hinting at the warm, lively days ahead while still maintaining an inviting atmosphere for outdoor activities. The consistent wind patterns suggest that while the intensity of gales diminishes, the refreshing air remains a cherished hallmark of life on the Isle of Man during this vibrant time of year.

Average May Wind Speed in Castletown

The chart displays monthly wind speed patterns in Castletown, 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.
JanFebMarAprMayJunJulAugSepOctNovDec8.510.58.55.86.4 m/s6.64.35.76.09.39.39.1
Data source: Castletown May wind data, generated using information from the Copernicus Climate Change Service.

How May Weather in Castletown Compares to Other Months

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

In comparing May and January, we see distinct differences in temperature and precipitation. May experiences slightly warmer temperatures, with a minimum of 5°C (42°F) and a maximum of 16°C (60°F), while January's temperatures range from a minimum of 3°C (38°F) to a maximum of 13°C (56°F). Additionally, May sees less precipitation, totaling 44 mm (1.7 in) over 9 days, compared to January's higher 81 mm (3.2 in) spread over 14 days. Humidity levels are also notably different, with May having an average of 79% and January at 89%. For more details on January weather, you can visit Castletown weather in January.

When comparing the weather in May and February, we see notable differences in temperature and precipitation. May tends to be milder, with average temperatures ranging from a minimum of 5°C (42°F) to a maximum of 16°C (60°F), whereas February is cooler, with temperatures averaging between 1°C (34°F) and 12°C (54°F). In addition to being warmer, May also experiences less rainfall, totaling 44 mm (1.7 in) over approximately 9 days, compared to February's 106 mm (4.2 in) spread over 18 days. Furthermore, humidity levels are slightly lower in May at 79%, compared to February’s higher humidity at 88%. For more detailed weather insights specific to February, you can visit Castletown weather in February.

When comparing the weather in May and March, it is evident that May tends to be warmer and drier. In May, temperatures range from a minimum of 5°C (42°F) to a maximum of 16°C (60°F), with an average of 10°C (51°F), while March sees lower temperatures, with a minimum of -1°C (30°F) and a maximum of 11°C (52°F), averaging at 7°C (45°F). Precipitation is notably less in May, with 44 mm (1.7 in) over 9 days, compared to March's higher total of 87 mm (3.4 in) across 18 days. Additionally, humidity levels are slightly lower in May at 79%, as opposed to March's 86%. For more details, you can check Castletown weather in March.

In comparing the weather between April and May, May presents a notable increase in temperatures, with a minimum of 5°C (42°F) and an average of 10°C (51°F), compared to April's minimum of 3°C (38°F) and average of 8°C (47°F). Additionally, the maximum temperature in May reaches 16°C (60°F), surpassing April's high of 13°C (56°F). Precipitation also sees a slight rise in May, with 44 mm (1.7 in) over 9 days compared to April's 36 mm (1.4 in) over 8 days, resulting in a slightly lower humidity in May at 79% compared to 84% in April. This transition between the months indicates a shift towards warmer and more dynamic weather patterns. For more detailed insights, you can visit Castletown weather in April.

May and June display distinct differences in weather patterns. May typically experiences milder temperatures with a minimum of 5°C and an average of 10°C, peaking at 16°C. In contrast, June sees a noticeable increase, starting from a minimum of 9°C and averaging 13°C, with a maximum reaching 17°C. Rainfall is also more significant in June, with 70 mm over 11 days compared to May's 44 mm across 9 days, and humidity levels remain fairly high in both months, at 79% in May and 81% in June. For more detailed insights into the weather conditions in June, you can visit Castletown weather in June.

In May, the weather is generally cooler, with temperatures ranging from a minimum of 5°C (42°F) to a maximum of 16°C (60°F) and an average of 10°C (51°F). This month also experiences higher humidity at 79% and sees about 44 mm (1.7 in) of precipitation spread over 9 days. In contrast, July brings warmer conditions, with temperatures starting at 12°C (53°F) and peaking at 19°C (67°F), averaging around 14°C (58°F). However, July has more rainfall, totaling 70 mm (2.8 in) across 12 days, while humidity levels remain similar at 78%. For more detailed information, you can check Castletown weather in July.

May and August present notable differences in weather patterns. In May, temperatures range from a minimum of 5°C (42°F) to a maximum of 16°C (60°F), with an average of 10°C (51°F). The month experiences about 44 mm (1.7 in) of precipitation over approximately 9 days, coupled with a humidity level of 79%. In contrast, August features milder temperatures, with a minimum of 12°C (54°F), an average of 15°C (59°F), and a maximum of 18°C (65°F). This month sees increased rainfall, totaling 94 mm (3.7 in) over 15 days, while maintaining a consistent humidity level of 79%. For more details on weather in August, you can check Castletown weather in August.

In May, the weather tends to be cooler with temperatures ranging from a minimum of 5°C (42°F) to a maximum of 16°C (60°F), averaging around 10°C (51°F). The month experiences about 44 mm (1.7 in) of precipitation over approximately 9 days, coupled with a humidity level of 79%.

In contrast, September sees warmer conditions with a minimum temperature of 10°C (51°F) and a maximum of 19°C (67°F), averaging 14°C (58°F). However, this month also brings more rain, with a total of 91 mm (3.6 in) of precipitation occurring over about 14 days and a higher humidity of 85%.

For further details about the weather patterns, you can explore Castletown weather in September.

In May, temperatures range from a minimum of 5°C (42°F) to a maximum of 16°C (60°F), with an average of 10°C (51°F). The month sees around 44 mm (1.7 in) of precipitation over approximately 9 days, accompanied by a humidity level of 79%. In contrast, October experiences slightly warmer temperatures with a minimum of 7°C (45°F) and a maximum of 17°C (63°F), averaging 13°C (55°F). However, it is significantly wetter, with 142 mm (5.6 in) of rain spread over about 18 days, and humidity rises to 90%. For more detailed insights, you can visit Castletown weather in October.

When comparing the weather in May and November, both months exhibit similar average temperatures, hovering around 10°C (51°F). However, May enjoys slightly warmer maximum temperatures of up to 16°C (60°F), while November peaks at 14°C (58°F). The contrast becomes apparent in terms of precipitation; May sees about 44 mm (1.7 in) over 9 days, whereas November experiences significantly higher rainfall with 143 mm (5.6 in) spread over 20 days. Additionally, November is characterized by higher humidity levels at 91%, compared to May's 79%. For more insights into November's weather conditions, you can visit Castletown weather in November.

May and December present contrasting weather patterns, particularly in terms of temperature and precipitation. In May, temperatures range from a minimum of 5°C (42°F) to a maximum of 16°C (60°F), with an average of 10°C (51°F). The month experiences 44 mm (1.7 in) of precipitation over about 9 days, with a humidity level of 79%. In contrast, December is cooler, with temperatures ranging from 4°C (39°F) to 13°C (56°F) and an average of 9°C (48°F). It sees a significant increase in precipitation, totaling 144 mm (5.7 in) across 22 days, along with higher humidity at 89%. This noticeable difference in weather makes May feel much milder and less damp compared to the often rainy and humid conditions of December. For more detailed information, check out Castletown weather in December.

Compare Castletown's Climate with Cities Worldwide

Conclusion: What to Expect From May Weather in Castletown

As May unfolds in Castletown, the weather shifts into a more inviting phase compared to the earlier months. With temperatures reaching a pleasant maximum of 16°C, there's a noticeable warmth that beckons longer outdoor adventures. The average temperature settles at a comfortable 10°C, offering a nice balance for enjoying the blossoming scenery. While May does bring about some rainfall, averaging about 44 mm over 9 days, the high humidity of 79% often enhances the lushness of the landscape rather than detracting from it. This month's temperate climate marks the perfect transition into the vibrant summer ahead, making it a delightful time to explore all that Castletown has to offer. For a comprehensive look at the weather throughout the year, visit Castletown Climate.