May Weather in Guaynabo, Puerto Rico

Last updated: August 31, 2025

May in Guaynabo, Puerto Rico offers a tropical experience characterized by warm temperatures and regular rainfall. With a maximum temperature reaching 31°C (87°F) and an average of 26°C (79°F), the climate is pleasantly warm, making it ideal for outdoor activities. However, visitors should prepare for some humidity at 75% and frequent showers, as the island sees about 98 mm (3.9 in) of precipitation over 24 days. This combination of warmth and moisture creates a lush, vibrant environment, perfect for exploring the lush landscapes and enjoying the unique cultural experiences that Guaynabo has to offer.

May Temperature in Guaynabo

In May, Guaynabo, Puerto Rico, experiences a delightful transition into warmer weather, with temperatures averaging a pleasant 26°C (79°F). The month begins with minimum temperatures around 22°C (72°F), gradually rising towards a maximum of 31°C (87°F), making it one of the warmest months before the summer heat sets in. This steady increase from April’s average of 25°C (77°F) showcases the area's tropical charm, inviting residents and visitors alike to bask in the sun. With consistently mild evenings, May in Guaynabo is perfect for outdoor activities and enjoying the vibrant local culture as the temperatures rise in this beautiful Caribbean locale.

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

The chart illustrates May temperature patterns in Guaynabo, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Guaynabo, 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).
JanFebMarAprMayJunJulAugSepOctNovDec757575777980818181807877
Data source: Temperature data for Guaynabo 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 Guaynabo

In Guaynabo, Puerto Rico, May marks a notable shift in the precipitation pattern, with an average rainfall of 98 mm (3.9 in). This month experiences increased humidity and a rise in wet days, tallying up to 24 days of rain, which is the highest number prior to the peak rainy months of August and September. The jump from April's 77 mm indicates that May is a transition period, as the island braces for the heavier rains of summer. As temperatures warm, the influx of moisture not only reflects in the downtown scenery but also rejuvenates the lush landscapes surrounding Guaynabo, embodying the vibrant essence of the island's tropical climate.

May Precipitation Trends in Guaynabo

The chart displays monthly precipitation patterns in Guaynabo, 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 Guaynabo, May typically receives around {2} mm ({3} inches) of precipitation spread over approximately {4} days.
JanFebMarAprMayJunJulAugSepOctNovDec485380779810012413020018312066
Data source: Precipitation data for May generated using information from the Copernicus Climate Change Service.
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May Humidity in Guaynabo

In Guaynabo, Puerto Rico, May brings a consistent humidity level of 75%, which aligns closely with the preceding months of April and February. This stability is characteristic of the region as it transitions into the warmer summer months, where humidity levels begin to rise notably. As the year progresses, a noticeable increase in humidity is observed in June (77%) and July (80%), signaling the onset of the sultry summer climate. Overall, May serves as a comfortable prelude to the season’s heightened humidity, maintaining a pleasant atmosphere ideal for enjoying the lush surroundings that Puerto Rico has to offer.

May Average Humidity in Guaynabo

This chart illustrates the average monthly humidity levels in Guaynabo, 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 Guaynabo is approximately {2}%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec76%75%74%75%75%77%80%80%79%78%78%76%
Data source: Humidity data for May generated using information from the Copernicus Climate Change Service.

May UV Index in Guaynabo

In May, Guaynabo, Puerto Rico experiences an extremely high UV Index of 14, reflecting a noticeable trend of increasing sun intensity as the year progresses. Following a peak in April, where the UV Index reached 13, May solidifies this trend with a burn time of just 10 minutes, urging residents and visitors alike to take serious precautions against sun exposure. This intensity is consistent with the months preceding and succeeding May, where values remain in the extreme category, underscoring the necessity for sun protection strategies year-round. For more information on UV levels throughout the year, visit the Guaynabo UV Index.

Maximum UV Index Levels in Guaynabo for May

The chart shows the monthly maximum UV Index (UVI) for Guaynabo 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 Guaynabo typically reaches {2}, which falls under the {3} exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec911131314131213131298
Data source: Guaynabo 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 Guaynabo

In Guaynabo, Puerto Rico, May shines as one of the sunniest months of the year, boasting an impressive 356 hours of sunlight. This peak in luminosity marks an upward trend from April's already bright total of 346 hours. As we transition from the earlier months, January and February both showcase fewer sunlit hours, at 257 and 303 respectively. However, the days grow noticeably longer as spring unfolds, with March and April offering tantalizing glimpses of the abundant sunshine to come. Following May, the summer months remain consistently bright, with June and July still basking in the sun with 343 and 353 hours, respectively. This delightful pattern of increasing sunlight through early summer enhances the charm of Guaynabo, inviting both residents and visitors to embrace the warmth of the island.

Monthly Sunshine Duration in Guaynabo: May Highlighted

The May sunshine duration represents the total number of hours Guaynabo 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.
JanFebMarAprMayJunJulAugSepOctNovDec257h303h346h346h356h343h353h349h313h313h299h319h
Data source: Guaynabo May Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Guaynabo During May

In Guaynabo, Puerto Rico, May offers a moderate 50% chance of sunny weather, making it a delightful time to enjoy the outdoors. As the seasons transition from the cooler months, where February boasts a notable 65% likelihood of sunshine, the sunny prospects wane slightly in the following months, with April dipping to 43%. While May holds steady with an equal split between sunny and cloudy days, it serves as a precursor to the summer months, especially June, which sees a sharp drop to just 20%. Overall, May strikes a balance, inviting residents and visitors alike to bask in the warmth before the seasonal shift brings increased rain.*

Percentage of Sunny Days in May in Guaynabo

The chart illustrates the percentage of sunny days in Guaynabo 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 Guaynabo experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec48%66%60%43%50%20%39%37%44%44%55%58%
Data source: Guaynabo May chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Guaynabo in May

In Guaynabo, Puerto Rico, May marks a delightful midpoint in the year with 12 hours of daylight, maintaining the trend set by the previous two months. As spring transitions toward summer, daylight gradually increases from 11 hours in January and February to a peak of 13 hours in June and July, creating ample opportunities for outdoor activities and enjoying the vibrant natural surroundings. As the year progresses, daylight begins to taper off slightly in late summer and fall, but May remains a time of abundant light, encouraging both locals and visitors to savor the beauty and warmth of this Caribbean paradise.

Average Daylight Hours in Guaynabo for May

The chart illustrates the variation in daylight duration in Guaynabo throughout the year, with May highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec11h 9m11h 32m12h 2m12h 33m12h 59m13h 11m13h 4m12h 42m12h 12m11h 42m11h 15m11h 2m
Data source: Guaynabo daylight hours, calculated by summing the hours between sunrise and sunset for each day.

May Winds in Guaynabo

In Guaynabo, Puerto Rico, the wind patterns in May showcase a gentle breeze with an average speed of 3.4 m/s (8 mph), consistent with the lighter winds typically seen in April. As spring transitions into summer, the wind speed slightly increases, mirroring a trend observed in the months leading up to May. Notably, the wind speeds pulse upwards in June and July, reaching 4.0 m/s (9 mph), while September marks a dip to 2.4 m/s (5 mph), hinting at the seasonal variations influenced by geography and weather systems. Overall, May serves as a delightful precursor to the breezier summer months, offering a perfect balance of warmth and refreshment for residents and visitors alike.

Average May Wind Speed in Guaynabo

The chart displays monthly wind speed patterns in Guaynabo, 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.
JanFebMarAprMayJunJulAugSepOctNovDec3.14.03.42.93.4 m/s3.74.03.52.42.62.73.3
Data source: Guaynabo May wind data, generated using information from the Copernicus Climate Change Service.

How May Weather in Guaynabo Compares to Other Months

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

In comparison to January, May experiences warmer temperatures with a minimum of 22°C (72°F) and an average high of 31°C (87°F), contrasted with January's minimum of 19°C (66°F) and a maximum of 29°C (84°F). While May has a higher average temperature, it also sees significantly more precipitation, totaling 98 mm (3.9 in) over 24 days, compared to January's 48 mm (1.9 in) across 16 days. Humidity levels are similar, with May at 75% and January at 76%. For more detailed weather information, you can view Guaynabo weather in January.

May and February present distinctly different weather patterns. In May, temperatures rise, with a minimum of 22°C (72°F) and averaging around 26°C (79°F), peaking at 31°C (87°F). February, on the other hand, experiences slightly cooler temperatures, starting at a minimum of 20°C (69°F) and averaging 24°C (75°F) with a maximum of 28°C (83°F). While both months feature high humidity levels of 75%, May sees significantly more rainfall, with 98 mm (3.9 in) spread over 24 days compared to February's 53 mm (2.1 in) over 18 days. For more details about February weather in Guaynabo, you can visit Guaynabo weather in February.

In May, the weather is generally warmer with temperatures ranging from a minimum of 22°C (72°F) to a maximum of 31°C (87°F), averaging around 26°C (79°F). The month experiences higher precipitation at 98 mm (3.9 in) over 24 days, resulting in a humidity level of 75%. In contrast, March is slightly cooler, with temperatures ranging from a minimum of 20°C (69°F) to a maximum of 29°C (85°F), and an average of 24°C (76°F). It also sees less precipitation, totaling 80 mm (3.2 in) over 21 days, while maintaining a similar humidity of 74%. For more detailed information, check Guaynabo weather in March.

In comparing the weather of April and May, both months exhibit warm temperatures and high humidity levels, but May tends to be slightly warmer and wetter. In May, the minimum temperature reaches 22°C (72°F), with averages of 26°C (79°F) and a maximum of 31°C (87°F), while April has a minimum of 21°C (70°F) and averages around 25°C (77°F), peaking at 30°C (86°F). Additionally, May sees increased precipitation, with 98 mm (3.9 in) over 24 days compared to April's 77 mm (3.0 in) across 20 days. This uptick in rainfall and the overall higher temperatures make May feel more humid, although both months maintain a consistent humidity level of 75%. For those interested in a detailed look, check out Guaynabo weather in April.

In comparing the weather between May and June, we observe that temperatures remain fairly consistent, with May averaging 26°C (79°F) and June slightly warmer at 27°C (80°F). The minimum temperatures in June are marginally higher, starting at 23°C (74°F) compared to May's 22°C (72°F). Both months experience similar precipitation levels, with May recording 98 mm (3.9 in) over 24 days and June slightly exceeding it at 99 mm (3.9 in) over 23 days. Humidity also sees a slight increase from 75% in May to 77% in June. For a more detailed look at June weather, you can visit Guaynabo weather in June.

In comparing the weather of May and July, both months feature warm temperatures with maximums reaching around 31°C (88°F). However, July experiences slightly warmer conditions overall, with an average temperature of 27°C (81°F) compared to May's 26°C (79°F). Additionally, July sees increased precipitation, totaling 124 mm (4.9 in) over 24 days, which is higher than May's 98 mm (3.9 in) during the same number of days. Humidity also rises in July, averaging 80%, compared to May's 75%. For more detailed information, you can check out Guaynabo weather in July.

May and August in Guaynabo exhibit similar warm weather patterns, with average temperatures slightly increasing from 26°C (79°F) in May to 27°C (81°F) in August. The minimum temperatures also rise slightly, from 22°C (72°F) in May to 23°C (74°F) in August. However, August experiences more rainfall, with precipitation reaching 130 mm (5.1 in) over 25 days compared to May's 98 mm (3.9 in) across 24 days. Additionally, humidity levels are higher in August at 80%, compared to May's 75%, contributing to a more tropical feel. For more insights, you can check Guaynabo weather in August.

May and September showcase similar warm temperatures but differ significantly in precipitation and humidity. In May, temperatures range from a minimum of 22°C (72°F) to a maximum of 31°C (87°F), with an average of 26°C (79°F) and a total precipitation of 98 mm (3.9 in) over 24 days. In contrast, September experiences slightly warmer conditions, with minimum temperatures around 23°C (74°F) and maxing out at 32°C (90°F), leading to an average temperature of 27°C (81°F). However, September sees increased rainfall, totaling 200 mm (7.9 in) across 27 days, accompanied by higher humidity at 79%. For more detailed information, check out Guaynabo weather in September.

In comparing the weather in May and October, both months exhibit warm temperatures, with average highs reaching around 31°C (88°F). May tends to start with slightly cooler temperatures, with an average of 26°C (79°F), while October has a marginally higher average at 27°C (80°F). However, October experiences more precipitation, accumulating 183 mm (7.2 in) over 27 days compared to May's 98 mm (3.9 in) over 24 days. Additionally, the humidity is slightly higher in October at 78% compared to 75% in May. For a more detailed look at October's weather, you can refer to Guaynabo weather in October.

In comparing the weather of May and November, both months experience warm temperatures with a minimum of around 22°C (72°F) and an average of approximately 26°C (79°F). However, May typically sees slightly higher maximum temperatures, reaching up to 31°C (87°F) compared to November's peak of 30°C (86°F). Rainfall is more frequent in November, with 120 mm (4.7 in) of precipitation over 23 days, as opposed to May's 98 mm (3.9 in) over 24 days. Humidity is also a bit higher in November at 78%, compared to May's 75%. For a detailed look at the weather trends, check out Guaynabo weather in November.

In May, the weather tends to be slightly warmer than in December, with average temperatures ranging from a minimum of 22°C (72°F) to a maximum of 31°C (87°F). Additionally, May experiences more precipitation, averaging 98 mm (3.9 in) over 24 days, coupled with a humidity level of 75%. In contrast, December offers a more moderate climate, with temperatures ranging from 21°C (71°F) to 30°C (86°F) and reduced rainfall of 66 mm (2.6 in) across 22 days, while the humidity remains close at 76%. For a detailed overview of December weather specifically in Guaynabo, you can visit Guaynabo weather in December.

Compare Guaynabo's Climate with Cities Worldwide

Conclusion: What to Expect From May Weather in Guaynabo

As the vibrant month of May unfolds in Guaynabo, expect a distinct shift in weather patterns compared to other months. Temperatures rise, averaging a warm 26°C, while maxing out at a pleasant 31°C, inviting outdoor activities and exploration. However, this warmth comes hand in hand with increased humidity levels around 75%, creating a tropical ambiance. May is also characterized by notable precipitation, with rain on nearly 24 days, accentuating the lush greenery and vibrant blooms of the region. Whether you're a local or a visitor, this blend of warmth and rain makes for a uniquely enchanting experience. For a deeper dive into Guaynabo's overall climate trends, check out Guaynabo Climate.