Last updated: August 31, 2025
In Isabela, Puerto Rico, May ushers in warm tropical weather, with maximum temperatures reaching 31°C (88°F), an average of 26°C (79°F), and minimums hovering around 23°C (74°F). This month witnesses a significant amount of rainfall, totaling 97 mm (3.8 in) across approximately 19 rainy days. The air carries a consistent humidity level of 75%, creating a lush environment perfect for exploring the island's natural beauty. Enjoy the vibrant landscapes and rich culture under the warm Caribbean sun, but be prepared for the occasional shower that nourishes this paradise.
In May, Isabela, Puerto Rico, experiences a delightful warm-up, marking the transition to summer with minimum temperatures around 23°C (74°F) and average highs reaching 31°C (88°F). This month sees a subtle increase in warmth from April, as average temperatures rise to 26°C (79°F), setting the tone for the hotter months ahead. The comforting beach days are complemented by a gradual increase in humidity, making it an ideal time for outdoor enthusiasts to soak up the vibrant natural beauty of the region. As the islands bask in these sunny conditions, May truly showcases the alluring tropical charm that captivates visitors.
In Isabela, Puerto Rico, May marks a significant uptick in precipitation, with an impressive 97 mm (3.8 in) of rain falling over 19 days. This increase not only represents the highest monthly total so far in the year, but it also sets the stage for the wetter summer months ahead, as both June and July follow closely with substantial rainfall. The trend in May suggests a transition into the more humid season, as the island shifts from the relatively drier spring months, evident in April's 66 mm (2.6 in) of rain over just 14 days. As storm patterns develop, May serves as a pivotal month, ushering in increased moisture that nurtures the lush landscapes and vibrant ecosystems of the region.
In Isabela, Puerto Rico, May brings a humidity level of 75%, maintaining a comfortable consistency seen since April. As we transition from early spring into summer, the humidity stabilizes, slightly below the spikes that will follow in the hotter months. Throughout the year, there's a clear upward trend starting in late spring, culminating in July and August where humidity peaks at 80%. This steady rise is a characteristic feature of Isabela's tropical climate, setting the stage for the warmer months ahead while allowing May to enjoy a moment of mild reprieve before the summer heat truly takes hold.
As the sun shines brightly in Isabela, Puerto Rico, the UV Index steadily climbs through the months, peaking at a striking 14 in May. This elevated level falls under the extreme exposure category, signifying a mere 10 minutes of unprotected sun exposure can lead to significant skin damage. Following closely, April and March also boast extreme indices of 13, warning residents and visitors alike to stay vigilant. Interestingly, the year begins with a very high index of 9 in January, tapering off to a more moderate 8 by December. The prolonged stretch of extreme UV ratings from February to October underscores the importance of sun safety in Isabela. For more insights into maintaining skin health against these rays, visit Isabela UV Index.
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In Isabela, Puerto Rico, the month of May shines particularly bright, boasting an impressive 361 hours of sunshine. This peak in brightness follows a steady increase from January's 261 hours and reflects a delightful trend that begins each year in the winter months. After reaching a peak in May, sunshine hours consistently remain high through July before settling back into the 350s as summer wanes. This pattern not only enriches the vibrant landscape of Isabela but also invites locals and tourists alike to bask in the tropical warmth of the island during its sunniest period. With May acting as a spectacular transition into longer, sun-filled days, it’s no wonder people flock to enjoy the beauty and energy of this enchanting destination.
In Isabela, Puerto Rico, the likelihood of sunny weather in May sits at a pleasant 55%, reflecting a trend of fluctuating sunshine throughout the year. Following a dip in April to 50%, May marks a slight rebound, positioning itself comfortably in the mid-range alongside January and December, both boasting similar odds. Notably, the spring months of February and March enjoy higher probabilities of sun, at 77% and 66% respectively, suggesting a transition into sunnier weather. As summer approaches, the chances dip significantly, with June plummeting to 31%. Therefore, while May offers a fair chance for sunny skies, it serves as a bridge between the vibrant sunshine of spring and the more overcast conditions characteristic of summer.
In Isabela, Puerto Rico, the daylight duration showcases a subtle yet captivating rhythm throughout the year. Starting from 11 hours in January and February, the days gradually lengthen, reaching 12 hours by March and maintaining that balance through April and May. As summer approaches, daylight peaks at 13 hours in June and July, inviting longer evenings filled with warmth and activity. The trend shifts back as late summer and autumn roll in, reverting to 12 hours from August to September, and finally decreasing to 11 hours in the cooler months of October through December. This annual cycle not only marks the passage of time but also heralds the vibrant seasonal changes that enrich life in this beautiful coastal town.
In Isabela, Puerto Rico, the winds of May pick up a gentle yet refreshing pace, with an average wind speed of 4.3 m/s (10 mph). This marks a slight increase from the calmer conditions of April, where breezes slowed to 3.8 m/s (9 mph). As spring transitions into summer, the winds fluctuate but generally remain consistent, with the months surrounding May—particularly June and July—often seeing higher speeds, reaching up to 5.3 m/s (12 mph). Overall, May serves as a harmonious bridge, where the winds begin to pick up again, setting the stage for the breezy summer months ahead, while still offering a pleasant atmosphere for outdoor activities.
Weather in Isabela varies notably across the year, with each month offering distinct climate conditions. This page compares May’s weather to other months in Isabela, focusing on differences in temperature, rainfall, humidity, and UV levels.
In May, temperatures are generally warmer, with a minimum of 23°C (74°F) and an average high of 31°C (88°F), compared to January's milder range, which sees a minimum of 20°C (69°F) and a maximum of 29°C (84°F). Additionally, May experiences significantly more precipitation, totaling 97 mm (3.8 in) over 19 days, while January receives only 34 mm (1.3 in) across 11 days. Humidity levels are quite similar in both months, with May at 75% and January slightly lower at 76%. For more details on January’s weather, you can visit Isabela weather in January.
In comparison to February, May experiences slightly warmer temperatures, with an average of 26°C (79°F) compared to February’s average of 25°C (76°F). While both months maintain a similar humidity level of 75%, May is characterized by higher precipitation, totaling 97 mm (3.8 in) over 19 days, in contrast to February's 39 mm (1.5 in) over just 13 days. This increase in rainfall in May suggests a wetter climate, making it noticeably different from the relatively drier conditions observed in February. For more detailed information on February weather in Isabela, you can visit Isabela weather in February.
May tends to be warmer than March, with average temperatures reaching 26°C (79°F) compared to March's 25°C (76°F). The maximum temperatures in May can climb to 31°C (88°F), while March peaks at 29°C (84°F). While both months experience a similar level of humidity, May has slightly higher levels at 75%, compared to March's 74%. Notably, May also sees more precipitation, with 97 mm (3.8 in) falling over 19 days, compared to March's 72 mm (2.8 in) across 17 days. For more detailed information about March weather, you can visit Isabela weather in March.
In comparing the weather between April and May, we see that May tends to be slightly warmer, with average temperatures rising from 25°C (78°F) in April to 26°C (79°F) in May. Both months experience similar humidity levels at 75%, but May also brings increased precipitation, averaging 97 mm (3.8 in) over 19 days compared to April's 66 mm (2.6 in) over 14 days. This shift in weather patterns indicates that while temperatures rise, May becomes noticeably wetter and more humid. For more detailed insights into April's weather, you can visit Isabela weather in April.
In comparing the weather between May and June, both months exhibit warm temperatures with only slight variations. May has a minimum temperature of 23°C (74°F) and an average temperature of 26°C (79°F), while June sees a slight increase to a minimum of 24°C (76°F) and an average of 27°C (81°F). Interestingly, both months share the same maximum temperature of 31°C (88°F). However, June experiences less precipitation at 85 mm (3.3 in) across 17 days, compared to May's 97 mm (3.8 in) across 19 days. Humidity levels are also slightly higher in June at 77%, compared to 75% in May. For more detailed insights on June weather, you can visit Isabela weather in June.
In comparing the weather between May and July, both months experience warm temperatures with only slight variations. May has a minimum temperature of 23°C (74°F) and an average of 26°C (79°F), while July sees a slightly higher minimum of 24°C (76°F) and an average of 27°C (81°F). Both months can reach a maximum of 31°C (88°F). Precipitation levels are fairly close, with May receiving 97 mm (3.8 in) over 19 days compared to July's 91 mm (3.6 in) spread across 18 days. Humidity levels are also higher in July, at 80%, compared to 75% in May. For more detailed information, you can check the conditions here: Isabela weather in July.
May and August both feature warm temperatures and significant humidity, but there are some notable differences. In May, temperatures range from a minimum of 23°C to a maximum of 31°C, with an average of 26°C. The month experiences 97 mm of precipitation across 19 days, pairing a humidity level of 75%. By contrast, August sees slightly warmer conditions, with temperatures ranging from a minimum of 24°C to a maximum of 32°C, averaging 27°C. Precipitation remains the same at 97 mm over 20 days, but humidity increases to 80%. For more detailed weather information, check out Isabela weather in August.
In comparing the weather of May and September, we see that both months enjoy warm temperatures, with averages hovering around 26°C (79°F) in May and slightly warmer at 27°C (81°F) in September. However, September experiences a bit more humidity, peaking at 79%, compared to May's 75%. While each month can reach a maximum of 31°C (88°F), September tends to have a higher minimum temperature at 25°C (77°F) versus May's 23°C (74°F). Rainfall also varies significantly, with September receiving more precipitation at 188 mm (7.4 in) over 23 days, compared to May's 97 mm (3.8 in) across 19 days. For more specific information about the weather in September, you can check Isabela weather in September.
In May, temperatures range from a minimum of 23°C (74°F) to a maximum of 31°C (88°F), with an average of 26°C (79°F). The month sees about 97 mm (3.8 in) of precipitation spread over 19 days, accompanied by a humidity level of 75%. In contrast, October experiences slightly higher temperatures, with a minimum of 24°C (76°F) and an average of 27°C (81°F), yet it also reaches the same maximum of 31°C (88°F). However, October is generally wetter, with 127 mm (5.0 in) of rainfall over 21 days and a humidity level of 78%. For more detailed information, you can visit Isabela weather in October.
May and November share a similar temperature range, with both months exhibiting minimum temperatures around 23°C (74°F) and average values of 26°C (79°F). However, May tends to be slightly warmer, peaking at 31°C (88°F) compared to November's maximum of 30°C (85°F). Precipitation levels are closely matched, with May receiving 97 mm (3.8 in) and November slightly higher at 99 mm (3.9 in), both occurring over 19 days. Humidity is marginally greater in November at 78%, compared to May's 75%. For more details on November conditions, you can check Isabela weather in November.
May and December present similar warm temperatures, with May generally being a bit hotter. In May, temperatures range from a minimum of 23°C (74°F) to a maximum of 31°C (88°F), with an average of 26°C (79°F). In contrast, December sees slightly cooler temperatures, with a minimum of 23°C (73°F), an average of 25°C (78°F), and a maximum of 30°C (86°F). However, May experiences significantly more precipitation, with 97 mm (3.8 in) spread over 19 days, compared to December's 43 mm (1.7 in) over 15 days. Humidity levels are comparable, with May at 75% and December slightly higher at 76%. For more detailed information, visit Isabela weather in December.
In May, Isabela experiences a warm and humid climate that sets the tone for the coming summer months. With temperatures ranging from a pleasant 23°C to 31°C, this month typically offers a balmy vibe, though it comes with an uptick in precipitation, as rain graces about half of the days. Compared to other months, May stands out for its blend of warmth and moisture, fostering a lush landscape that's perfect for exploration. For a deeper look into Isabela's climate patterns throughout the year, be sure to check out Isabela Climate.