Last updated: August 21, 2025
May in Castel, Guernsey showcases a delightful blend of mild temperatures and occasional showers, perfect for welcoming the spring season. With maximum temperatures reaching 18°C (65°F) and an average of 12°C (54°F), the weather invites both outdoor activities and leisurely strolls. However, residents and visitors should prepare for 8 days of rain, accumulating about 55 mm (2.2 in), and factor in a relatively high humidity level of 81% for that refreshing coastal feel. Whether exploring the charming surroundings or enjoying the lush greenery, May offers a picturesque backdrop in this serene slice of the Channel Islands.
In May, Castel, Guernsey begins to shed the chill of winter, with temperatures gradually rising to a minimum of 7°C (45°F) and peaking at a delightful 18°C (65°F). The average temperature stabilizes around 12°C (54°F), marking a noticeable shift as the island embraces spring. This transition not only brings milder weather compared to the cooler months—where January and February linger around 3°C to 0°C (37°F to 33°F)—but also sets the stage for the warmth of summer ahead. As the days grow longer, May offers the perfect balance of fresh breezes and sunny spells, enticing visitors to enjoy Castel's stunning landscapes and vibrant outdoor activities.
May in Castel, Guernsey typically experiences a moderate precipitation level of 55 mm (2.2 in) over about 8 days, mirroring the lighter spring rains that give way to the lush greenery of summer. This month showcases a significant decline in rainfall from the heavy showers of earlier months, particularly April's 34 mm (1.3 in), and serves as a precursor to the slightly wetter June, which sees an uptick to 59 mm (2.3 in). The overall trend indicates that while May brings adequate moisture, it’s a more tranquil period compared to the preceding winter months, laying the foundation for the vibrant landscapes that characterize the summer months ahead.
In May, humidity levels in Castel, Guernsey begin their descent, dropping to 81%, a marked shift from the cozy grip of winter and early spring. This decline reflects the transition into the warmer months, as the air becomes lighter and less saturated. Such a drop is part of a wider trend observed from April's 84% and serves as an early indication of the approaching summer. As the season progresses, humidity continues to decrease, reaching its lowest point in July at 63%, before slowly rising again in the late summer and autumn months. The gradual change in humidity not only signifies the arrival of sunnier days but also sets the tone for the vibrant outdoor activities that the island has to offer.
As spring transitions into summer, the UV Index in Castel, Guernsey rises significantly in May, reaching a level of 7, which falls within the high exposure category. This marks a noticeable increase from April’s 6 and is a sign that sun protection becomes essential, as the burn time diminishes to just 25 minutes. The upward trend continues into June, where the UV Index peaks at 9, highlighting the necessity for proactive sun safety measures. Therefore, it's crucial for residents and visitors alike to stay informed and prepared for the strengthening sun, ensuring they enjoy the beautiful days ahead while minimizing their risk. For more detailed information, check out the Castel UV Index.
UV Risk Categories
May heralds a brilliant embrace of sunshine in Castel, Guernsey, as the island basks in 414 hours of radiant light, marking a significant leap from the 359 hours recorded in April. This upward trend in glorious daylight continues into June, which reaches an impressive 416 hours, showcasing the growing warmth and vibrancy of the season. As spring transitions into summer, the sunlit hours peak in July with 436 hours, before gradually easing into August's 396 hours. This pattern beautifully illustrates not just a seasonal peak in daylight but also reflects the inviting warmth that draws residents and visitors alike to explore the picturesque landscapes of Guernsey.
As spring unfolds, Castel, Guernsey sees a notable shift in sunny weather, with May showcasing a 42% chance of sunshine. Although this figure is a dip from the high of 62% in April, it's a significant leap compared to the winter months, where January and February languish at 21% and 28% respectively. Following May, the likelihood of sunny days fluctuates again, peaking in July at 49% and falling to 33% in June. This trend highlights May as a transitional month, poised between the vibrant sunshine of late spring and the varying summer weather, making it an ideal time for outdoor activities amid fresh blooms and mild temperatures.
As spring unfolds into summer in Castel, Guernsey, the daylight duration sees a significant transformation, enhancing the beauty of the landscape and the island's vibrant lifestyle. Starting January with a modest 8 hours of daylight, the days gradually lengthen, reaching 10 hours by February and 11 hours in March. The trend accelerates through April, where daylight stretches to 13 hours, and blossoms into May with a lush 15 hours of sunlight. This peak illuminates the early summer months, with June boasting an impressive 16 hours. As summer wanes, daylight begins to recede, settling back to 15 hours in July and 14 hours in August, before tapering off to 12 hours in September and further to 10 hours in October. The cycle continues into the cooler months, with November and December returning to the shorter days, with just 9 and 8 hours of daylight, respectively. This rhythm of light not only marks the changing seasons but also enriches the experience of life in Castel, highlighting the interplay of nature and daily routines.
In May, the winds in Castel, Guernsey, present a refreshing shift, averaging 8.2 m/s (18 mph), slightly more invigorating than the calmer breezes of April. This month marks the transition into the warmer season, with wind speeds showing a gradual recovery from their late spring lows, which dipped to a mere 6.8 m/s (15 mph). Following a consistent pattern, May maintains a stronger gales throughout the month, setting the stage for the summer months ahead. Notably, while June sees a decline in wind speeds to 4.6 m/s (10 mph), it's interesting to observe how May serves as a bridge, offering a taste of the gusty charm that characterizes the more blustery months to come.
Weather in Castel varies notably across the year, with each month offering distinct climate conditions. This page compares May’s weather to other months in Castel, focusing on differences in temperature, rainfall, humidity, and UV levels.
In May, temperatures typically range from a minimum of 7°C (45°F) to a maximum of 18°C (65°F), with an average of 12°C (54°F). The month sees approximately 55 mm (2.2 in) of precipitation over about 8 days, accompanied by a humidity level of 81%. In contrast, January is cooler, featuring temperatures from a minimum of 3°C (37°F) to a maximum of 14°C (57°F), averaging at 9°C (49°F). This month has higher precipitation levels at 94 mm (3.7 in) across 14 days, with humidity peaking at 89%. For more detailed information, you can check Castel weather in January. Overall, May offers milder temperatures and less rain compared to the chillier and wetter conditions of January.
In comparing the weather between February and May, it's clear that May generally offers milder temperatures and less precipitation. During February, temperatures range from a minimum of 0°C (32°F) to a maximum of 13°C (56°F), with an average of 9°C (48°F). In contrast, May enjoys a broader range with minimums of 7°C (45°F) and maximums peaking at 18°C (65°F), alongside an average of 12°C (54°F).
However, February experiences more rainfall, totaling 86 mm (3.4 in) over 16 days compared to May's 55 mm (2.2 in), spread over only 8 days. Humidity remains high throughout both months, with February at 88% and May slightly lower at 81%. For a more detailed look at the weather in February, you can visit Castel weather in February.
In comparing the weather of May and March, we can see notable differences in temperature and precipitation. May tends to be warmer, with average temperatures ranging from a minimum of 7°C (45°F) to a maximum of 18°C (65°F), while March has cooler temperatures that range from 0°C (32°F) to 13°C (55°F). Additionally, May experiences less rainfall, with a total precipitation of 55 mm (2.2 in) over 8 days, compared to March's higher precipitation of 73 mm (2.9 in) spread across 15 days. Humidity levels are slightly lower in May at 81%, compared to March's 85%. For more detailed insights into March weather, you can check Castel weather in March.
In comparing the weather between April and May, we see that May enjoys slightly warmer temperatures, with an average of 12°C (54°F) compared to April's 10°C (50°F). The minimum temperatures in May are also a bit higher, at 7°C (45°F) versus April's 5°C (41°F), while the maximums rise to 18°C (65°F) from April's 15°C (59°F). Additionally, May experiences more precipitation, totaling 55 mm (2.2 in) over the same number of rainy days (8), although the overall humidity is slightly lower in May at 81% compared to April's 84%. For a closer look at April's weather specifics, check out Castel weather in April.
May and June showcase subtle shifts in weather patterns, with June generally experiencing milder temperatures. In May, the temperature ranges from a minimum of 7°C (45°F) to a maximum of 18°C (65°F), averaging around 12°C (54°F). In contrast, June sees slightly warmer conditions, with temperatures varying from a minimum of 11°C (53°F) to a maximum of 19°C (67°F) and an average of 14°C (58°F). Both months experience similar levels of precipitation, with May recording 55 mm (2.2 in) and June slightly higher at 59 mm (2.3 in), although both have precipitation on about 8 days. Humidity levels are also comparable, with May at 81% and June slightly lower at 77%. For more specific details on June weather conditions, you can visit Castel weather in June.
In comparing the weather between May and July, we see a notable increase in temperatures. May experiences minimum temperatures around 7°C (45°F) with an average of 12°C (54°F) and a maximum of 18°C (65°F). In contrast, July offers milder conditions, where minimum temperatures rise to 14°C (57°F), with averages of 16°C (62°F) and maxima reaching 21°C (70°F). Precipitation also differs, with May receiving 55 mm (2.2 in) over 8 days, while July has a lighter precipitation total of 37 mm (1.5 in) across 7 days. Furthermore, humidity levels are higher in May at 81%, compared to July's more comfortable 63%. For more details, check out Castel weather in July.
Weather in May and August presents a striking contrast. In May, temperatures range from a chilly 7°C (45°F) at night to a mild 18°C (65°F) during the day, with an average of around 12°C (54°F). The month experiences about 55 mm (2.2 in) of precipitation over 8 days and high humidity levels at 81%. In comparison, August offers warmer conditions with minimum temperatures of 14°C (57°F) and maximums reaching 22°C (72°F), averaging 17°C (63°F). Rainfall is slightly less at 50 mm (2.0 in) but still spreads over 9 days, accompanied by a reduction in humidity to 71%. For more detailed information, check out Castel weather in August.
May and September offer distinct weather profiles, reflecting the transition from spring to autumn. In May, temperatures range from a cooler minimum of 7°C (45°F) to a maximum of 18°C (65°F), with an average of 12°C (54°F). The month tends to be quite humid with an average humidity of 81% and experiences about 55 mm (2.2 in) of precipitation over 8 days. In contrast, September warms up slightly, with minimum temperatures of 12°C (54°F) and a higher average of 17°C (62°F), peaking at 21°C (71°F). Though it sees a bit more rainfall at 63 mm (2.5 in) across 9 days, the humidity drops to 76%. For a detailed exploration of what to expect weather-wise, check out Castel weather in September.
May and October exhibit distinct weather patterns that highlight the transition from spring to autumn. In May, temperatures range from a minimum of 7°C (45°F) to a maximum of 18°C (65°F), with an average of 12°C (54°F). The month sees about 55 mm (2.2 in) of precipitation over approximately 8 days, accompanied by a comfortable humidity level of 81%. In contrast, October is slightly warmer, with temperatures ranging from a minimum of 9°C (48°F) to a maximum of 20°C (68°F), averaging 15°C (59°F). However, it experiences significantly higher precipitation at 144 mm (5.7 in) over around 17 days, coupled with increased humidity at 89%. For a more detailed look at October weather, visit Castel weather in October.
In May, the weather is generally mild with temperatures ranging from a minimum of 7°C (45°F) to a maximum of 18°C (65°F), accompanied by an average temperature of 12°C (54°F). The month receives about 55 mm (2.2 in) of precipitation over approximately 8 days, with humidity levels around 81%. In contrast, November presents a similar average temperature of 12°C (54°F), but with slightly lower maximum temperatures reaching up to 17°C (63°F) and minimum temperatures of 6°C (43°F). However, November sees a significant increase in precipitation, totaling 126 mm (5.0 in) over 18 days, and elevated humidity at 90%. For more information on the weather conditions in November, you can visit Castel weather in November.
In May, temperatures generally range from a minimum of 7°C (45°F) to a maximum of 18°C (65°F), with an average of 12°C (54°F). The month experiences moderate precipitation of about 55 mm (2.2 in) over approximately 8 days, accompanied by a humidity level of 81%. In contrast, December tends to be cooler, with temperatures ranging from 5°C (41°F) to 14°C (58°F) and an average of 11°C (51°F). This month sees significantly higher precipitation, totaling 163 mm (6.4 in) across about 21 days, and an increase in humidity to 90%. For more detailed information, check out Castel weather in December.
As May arrives in Castel, the weather transforms into a refreshing springtime ambiance, characterized by a mild temperature range that encourages outdoor activities. Unlike the colder months, May brings a significant increase in warmth, beckoning flowers to bloom and nature to flourish. While precipitation is relatively moderate, with a few rainy days scattered throughout the month, the overall humidity remains high, creating a lush environment. This unique blend of warmth and moisture sets May apart from the prior winter months, offering residents and visitors a delightful taste of the season. For more details on what to expect in this charming locale, check out the Castel Climate.