Last updated: August 31, 2025
May in Castries, Saint Lucia offers a delightful blend of warm temperatures and a touch of humidity. With daily highs reaching a comfortable 31°C (88°F) and an average temperature around 27°C (81°F), the weather is perfect for exploring the vibrant local culture. However, be prepared for the occasional rainfall, as 39 mm (1.6 in) of precipitation falls over 13 days throughout the month. The humidity level hovers around a notable 80%, creating a tropical atmosphere that adds to the island's charm. Embrace the warmth and occasional showers for a memorable experience in this Caribbean paradise.
In May, Castries, Saint Lucia basks in warm tropical bliss, with temperatures reflecting a delightful transition toward summer. The minimum temperature reaches a comfortable 23°C (74°F), hinting at balmy evenings, while the average climbs to a pleasant 27°C (81°F), ideal for daytime adventures or beach lounging. With a peak of 31°C (88°F), the month showcases a consistent warmth that sets the tone for the forthcoming summer months. This upward trend in temperature from the cooler beginnings of the year, particularly evident from April to May, suggests a vibrant and inviting atmosphere, perfect for exploring the scenic beauty and vibrant culture of this Caribbean paradise.
May in Castries, Saint Lucia, marks a transition into a wetter season, with precipitation levels rising to an average of 39 mm (1.6 in) over 13 days of rain. This slight increase from April’s 35 mm (1.4 in) reflects the beginning of the island's lush, tropical greenery flourishing as humidity intensifies. As the month progresses, rainfall continues to escalate into June, where totals jump significantly to 65 mm (2.6 in). Such patterns highlight a clear trend: May serves as a precursor to the more intensely rainy months ahead, paving the way for the dramatic increases experienced in mid-year, making it an essential time for nature's rejuvenation.
In May, the humidity in Castries, Saint Lucia settles at a comfortable 80%, mirroring the levels observed in the preceding months of February, March, and April. This reveals a trend of relatively stable humidity rates leading into the warmer months, with May serving as a transitional period before a gradual increase begins in June and continues into the summer. The consistent humidity levels during this time create a pleasant tropical atmosphere, allowing visitors to enjoy the stunning scenery without feeling overwhelmed by muggy conditions. As the island moves into the peak heat of summer, it’s clear that while May remains mild, the humidity will soon begin to rise, emphasizing the lush vibrancy of Castries’ environment.
In May, Castries, Saint Lucia experiences a notably high UV Index of 14, categorizing the sun exposure as extreme. With a burn time of just 10 minutes, the risk of skin damage is significant, urging residents and visitors to take precautions when outdoors. This trend of elevated UV levels continues from April and stretches into the early summer months, peaking again in August. Observing these patterns, it's crucial to stay vigilant throughout May and prepare for consistent extreme UV conditions. For further insights on the UV Index, check out Castries UV Index.
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May truly shines as a highlight in Castries, Saint Lucia, boasting an impressive 355 hours of sunlight. This marks a peak in the spring months, following the steady increase from January's 268 hours to February's 304 hours and March's 345 hours. April also enjoyed a generous 336 hours, setting the stage for May's brilliant luminosity. However, as the heat of summer approaches, the sunlight hours do experience a slight decrease in June to 325 hours. Nevertheless, the trend remains clear: May offers some of the best days for basking in the sun, making it a perfect time for visitors and locals alike to enjoy the vibrant beauty of this paradise.
In Castries, Saint Lucia, the likelihood of sunny weather in May stands at 45%, reflecting a moderate chance of clear skies as the island transitions into the hotter months. This is a slight increase from April, which has a 36% chance of sunshine, but shows a dip compared to higher probabilities seen in February (66%) and November (58%). The months preceding May present varying prospects, with March at 42% and April at 36%, signaling an overall trend of fluctuating sunshine chances as the year progresses. As summer approaches, the likelihood in June decreases further to 29%, suggesting that visitors might want to seize the opportunity in May for a delightful mix of sun and relaxation before the peak rainy season begins.
In Castries, Saint Lucia, daylight duration reveals a captivating trend throughout the year. From January to February, residents enjoy a consistent 11 hours of daylight, setting a warm, sunlit tone for the new year. As spring approaches, March and April see a gentle increase to 12 hours, heralding the longer days of the tropical season. This splendid 12-hour span persists from May through September, offering ample daylight for outdoor adventures and relaxation. As the year winds down in October, the daylight returns to 11 hours and remains steady through to December, concluding the cycle with a sense of continuity and balance between light and dark. This rhythm of daylight fosters a vibrant lifestyle, celebrating the beauty of each season in paradise.
In May, Castries enjoys a refreshing transition as average wind speeds reach 6.4 m/s (14 mph), matching the mild breezes of June and December. This gentle wind heralds a shift from the calmer April days, creating an inviting atmosphere for outdoor activities and exploration. Throughout the year, the city experiences a dynamic range of winds, with February showcasing the highest velocity at 7.3 m/s (16 mph), while September brings a notable dip to 3.9 m/s (9 mph). As summer approaches, the winds gradually become more favorable, sustaining the playful spirit of the Caribbean. The overall trend reveals that while summer months maintain a consistent gentle breeze, the slightly stronger winds in early spring and late fall impulsively remind us of the island's vibrant natural rhythms.
Weather in Castries varies notably across the year, with each month offering distinct climate conditions. This page compares May’s weather to other months in Castries, focusing on differences in temperature, rainfall, humidity, and UV levels.
When comparing the weather in May and January, both months exhibit warm temperatures typical of a tropical climate. In May, the average temperature slightly increases to 27°C (81°F), with maximums reaching 31°C (88°F) and a notable humidity level of 80%. Precipitation in May averages 39 mm (1.6 in) over 13 days. Meanwhile, January showcases very similar conditions, with an average temperature of 26°C (78°F) and maximums of 30°C (86°F), accompanied by slight precipitation of 36 mm (1.4 in) over 15 days. Thus, while both months are warm and humid, May is typically a bit hotter and wetter than January. For a detailed overview, visit Castries weather in January.
Comparing the weather between May and February reveals some interesting patterns. In May, temperatures are slightly warmer, with a minimum of 23°C (74°F) and an average of 27°C (81°F), while February has a minimum of 21°C (71°F) and averages 25°C (78°F). The maximum temperature in both months is quite close, with May reaching 31°C (88°F) and February peaking at 30°C (86°F). Precipitation levels are relatively similar, with May seeing 39 mm (1.6 in) over 13 days and February experiencing 33 mm (1.3 in) over 12 days. Both months maintain a high humidity level of around 80%. For more specific details about February's weather, you can check Castries weather in February.
When comparing the weather in May and March, we see some subtle differences. In May, temperatures range from a minimum of 23°C (74°F) to a maximum of 31°C (88°F), with an average of 27°C (81°F). March offers slightly cooler temperatures, with a minimum of 22°C (72°F) and a maximum of 30°C (85°F), averaging 26°C (79°F). Both months experience similar precipitation levels, with May receiving 39 mm (1.6 in) over 13 rainy days and March registering 38 mm (1.5 in) across 15 days. Notably, humidity remains constant at 80% for both months. For more detailed insights, you can refer to Castries weather in March.
In comparing the weather of May and April, both months feature similar temperature ranges, with May showing a slight increase in average temperature at 27°C (81°F) compared to April's 26°C (80°F). The minimum temperatures in both months remain consistent at 23°C (74°F). However, May experiences a marginally higher amount of precipitation at 39 mm (1.6 in) over 13 days, compared to April's 35 mm (1.4 in) over 14 days, indicating a slightly wetter month ahead. Humidity levels also remain comparable, with May at 80% and April at 79%. For more specific insights on April weather, you can visit Castries weather in April.
In comparing the weather of May and June, both months share similar temperature ranges, with May having a minimum of 23°C (74°F), an average of 27°C (81°F), and a maximum of 31°C (88°F), while June slightly increases to a minimum of 24°C (75°F). However, June experiences more precipitation, with a total of 65 mm (2.6 in) over 16 days compared to May’s 39 mm (1.6 in) across 13 days. The humidity also rises slightly in June to 83%, up from 80% in May, creating a more tropical feel as the month progresses. For detailed weather insights, you can check Castries weather in June.
In comparing the weather between May and July, both months share a similar average temperature of 27°C (81°F) and peak at 31°C (88°F to 89°F in July). However, July experiences slightly higher minimum temperatures, starting at 24°C (76°F) compared to May's 23°C (74°F). While May has a total precipitation of 39 mm (1.6 in) over 13 days, July sees a significant increase in rainfall, totaling 105 mm (4.1 in) over 24 days, contributing to the higher humidity levels in July at 84%, compared to May's 80%. This shift in weather patterns highlights a transition from the relatively drier conditions of May to the wetter, more humid environment typical of July. For more details on July weather in Castries, you can visit Castries weather in July.
May and August showcase similar temperature ranges, with average highs around 31°C (88°F) for both months. However, May tends to be slightly cooler, with an average temperature of 27°C (81°F) compared to August's 28°C (82°F). Notably, August experiences significantly more precipitation, with 113 mm (4.5 in) over 25 days, while May sees only 39 mm (1.6 in) over 13 days. Humidity levels remain consistent, with May at 80% and August slightly higher at 81%. For more detailed information, check out Castries weather in August.
In comparing the weather between May and September, both months exhibit warm temperatures, but September tends to be slightly warmer overall. In May, the average temperature is around 27°C (81°F), with highs reaching 31°C (88°F), while in September, the average is a bit higher at 28°C (83°F), peaking at 32°C (90°F). Additionally, September is significantly wetter, receiving 121 mm (4.8 in) of precipitation over 19 days compared to May's 39 mm (1.6 in) over 13 days. Despite both months having a consistent humidity level of 80%, the increased rainfall in September may lead to a more humid atmosphere. For a detailed look at September weather, check out Castries weather in September.
In comparing the weather of May and October, both months present warm temperatures, with average highs around 27°C (81°F). However, October tends to be slightly warmer, with a maximum temperature of 32°C (89°F) compared to May's 31°C (88°F). While May experiences moderate precipitation of 39 mm (1.6 in) over 13 days, October sees a significant increase, with 128 mm (5.1 in) of rainfall spread over 21 days, contributing to a higher humidity level of 82%. For a more detailed look at weather conditions during October, you can refer to Castries weather in October.
May and November in Castries present similar average temperatures, both hovering around 27°C (81°F). However, November tends to be slightly cooler with minimum temperatures at 24°C (75°F) compared to May's 23°C (74°F). In terms of precipitation, November significantly stands out with 103 mm (4.1 in) of rain over 21 days, while May sees only 39 mm (1.6 in) spread across 13 days. Additionally, November's humidity is slightly higher at 83%, compared to May's 80%. For more detailed weather insights, you can check Castries weather in November.
May and December exhibit relatively similar weather patterns, though there are some notable differences. In May, temperatures range from a minimum of 23°C (74°F) to a maximum of 31°C (88°F), with an average of 27°C (81°F). The month experiences about 39 mm (1.6 in) of precipitation over 13 days and humidity levels around 80%. In contrast, December features slightly cooler temperatures, with a minimum of 22°C (72°F), an average of 26°C (80°F), and a maximum of 30°C (86°F). Precipitation is a bit higher at 46 mm (1.8 in), spanning 16 days, while humidity increases slightly to 82%. For a detailed look at the December weather in Castries, you can check Castries weather in December.
As May ushers in the warm embrace of summer in Castries, the weather offers a delightful blend of warmth and humidity, setting it apart from the cooler months that precede it. With average temperatures rising to a comfortable 27°C (81°F) and maximums reaching up to 31°C (88°F), visitors can expect a balmy atmosphere perfect for exploring the vibrant landscapes of Saint Lucia. However, be prepared for occasional tropical rain, with about 13 days of precipitation adding a refreshing contrast to the sultry conditions. The high humidity levels of around 80% create a lush, vibrant environment, making May a unique experience in Castries. For more insights into weather patterns throughout the year, check out the detailed information at Castries Climate.