Last updated: August 21, 2025
In May, San Jose, Costa Rica experiences a delightful blend of warmth and moisture, making it a vibrant time of year. With maximum temperatures reaching 26°C (79°F) and an average of 19°C (67°F), the climate is pleasantly mild. However, visitors should prepare for the rainy season, as this month sees approximately 425 mm (16.7 in) of precipitation, spread over 29 days. Humidity hovers around 69%, adding to the lush, tropical atmosphere that characterizes this beautiful city. Whether you’re exploring the rich culture or nature, the dynamic weather presents both challenges and opportunities for unforgettable experiences.
In May, San Jose, Costa Rica experiences a delightful continuation of the warm season, with temperatures gently rising. The month typically begins with minimums around 14°C (58°F), transitioning to averages of 19°C (67°F) and peaking at maxima of 26°C (79°F). This pattern marks a slight increase from April, where warmer daytime highs of 26°C (80°F) begin to settle in, making May pleasantly warm but not overly humid. As the month progresses, the balmy climate makes it an inviting time for outdoor adventures, before the cooler nights set in, reflecting the region’s lovely spring atmosphere. Embrace this transitional period, as it showcases the appealing mildness of San Jose’s weather.
May in San Jose, Costa Rica, stands out as the tipping point into the rainy season, with a staggering 425 mm (16.7 in) of precipitation recorded over 29 days. This substantial amount marks a sharp increase from the preceding months, underscoring May as one of the wettest periods of the year. Following April's significant rainfall of 113 mm (4.4 in), the jump in precipitation signals a transition towards more consistent and heavier rainfall patterns that continue into June and beyond. This trend highlights May's pivotal role in establishing the lush, vibrant landscapes characteristic of Costa Rica as it embraces its rainy season. As the month progresses, the almost daily showers keep the environment rich and green, while inviting a surge in natural beauty that defines this tropical paradise.
In May, San Jose, Costa Rica, experiences a slight increase in humidity, reaching 69%—a trend that signals the approach of the rainy season. This increase marks a subtle rise from the previous months, as humidity fluctuates between 66% and 68% from January to April. As the year progresses into the wetter months of June and July, humidity levels will soar to 84% and 85%, respectively, creating a lush, vibrant environment typical of this tropical region. Thus, May serves as a notable transitional period, with its mild humidity inviting both locals and tourists to enjoy the rich greenery before the heavy rains set in.
In May, San Jose, Costa Rica, experiences an impressive UV Index of 14, maintaining its status as an extreme exposure category, where a mere 10 minutes of unprotected skin can lead to sunburn. This month continues the trend observed from the beginning of the year, with only a slight dip from April’s peak of 16, indicating that the intense sun remains a formidable presence. Following this pattern, the UV Index is consistently high throughout the surrounding months, emphasizing the need for sun protection and awareness. Travelers and locals alike should take care to stay safeguarded against these potent rays. For more detailed information on UV exposure in San Jose, check out San Jose UV Index.
UV Risk Categories
May in San Jose, Costa Rica, offers a delightful blend of sunshine, with 248 hours of daylight illuminating the lush landscape. This month sees a slight dip compared to the sun-soaked highs of March, which boasts 329 hours, yet it remains significantly sunnier than mid-year months like July, with only 229 hours. Notably, the early part of the year, especially February and March, shines brightly, while May stands out as a transitional month, bridging the robust sunlight of the dry season to the more scattered rays of the rainy season ahead. While the sun isn’t quite as abundant as in April, May's warmth and light continue to invite exploration of this vibrant city, making it a cherished time for both locals and visitors alike.
As May rolls into San Jose, Costa Rica, the likelihood of sunny weather takes a noticeable dip, with only a 12% chance of sun. This marks a significant decrease from the preceding months, especially compared to January's 47% and February's 42%. The trend showcases a transition into the rainy season, beginning in earnest by late April, which continues to affect the weather into June and beyond. With May's cloudy disposition, travelers should anticipate more overcast skies and potential downpours, making it a stark contrast to the sun-kissed days of earlier months.
In San Jose, Costa Rica, May brings an enduring embrace of daylight, lasting 12 hours—a pattern that persists from March through June. As the year begins, daylight starts at 11 hours in January and February, before gradually extending into the spring months. This consistent 12-hour duration offers a perfect backdrop for outdoor activities, allowing residents and visitors alike to enjoy the vibrant life of the city. As the year wanes into October, daylight begins to recede back to 11 hours, highlighting a seasonal rhythm that characterizes the tropical climate. Throughout the year, the shift in daylight length not only marks time but also enhances the beauty of everyday life in this lush locale.
In May, San Jose, Costa Rica experiences a gentle decline in wind speed, averaging 1.6 m/s (4 mph), making it one of the calmer months of the year. This trend follows the slight reduction seen in April, which recorded 1.7 m/s (4 mph). As the dry season transitions toward the rainy months, the winds continue their softening trend, with June expected to dip further to 1.3 m/s (3 mph). This subtle shift not only enhances the tranquility of the city but also sets the stage for the lush transformation that the rainy season brings. Overall, May serves as a serene pause before the winds take a slower course, offering residents and visitors a perfect backdrop to enjoy the vibrant culture of this remarkable destination.
Weather in San Jose varies notably across the year, with each month offering distinct climate conditions. This page compares May’s weather to other months in San Jose, focusing on differences in temperature, rainfall, humidity, and UV levels.
When comparing the weather in May and January, we see notable differences in temperature, precipitation, and overall humidity. May experiences warmer temperatures, with a minimum of 14°C (58°F) and an average of 19°C (67°F), reaching a maximum of 26°C (79°F). In contrast, January starts slightly cooler, with minimums of 11°C (53°F), averaging 17°C (63°F), and peaking at 24°C (76°F).
Precipitation also varies significantly between the two months; May sees a substantial 425 mm (16.7 in) over 29 days, while January has much less, totaling 93 mm (3.7 in) over just 11 days. Despite these differences, both months maintain similar humidity levels, with May at 69% and January at 68%. For more detailed insights, you can visit San Jose weather in January.
When comparing the weather in May and February, it’s clear that May tends to be warmer and much wetter. In May, temperatures range from a minimum of 14°C (58°F) to a maximum of 26°C (79°F), with an average of 19°C (67°F). In contrast, February's temperatures are slightly cooler, with a minimum of 11°C (52°F) and a maximum of 25°C (78°F), averaging 17°C (64°F). Precipitation also sees a significant difference, as May experiences 425 mm (16.7 in) over 29 days, while February has a much dryer climate with only 43 mm (1.7 in) over 12 days. Humidity levels are relatively similar, with May at 69% and February at 68%. For more detailed insights into February weather, visit San Jose weather in February.
In comparing the weather of May and March, May tends to be warmer with an average temperature of 19°C (67°F), while March averages slightly cooler at 18°C (64°F). Both months experience comfortable minimum temperatures, with May starting at 14°C (58°F) and March at 11°C (53°F). However, May sees significantly more rainfall, with 425 mm (16.7 in) of precipitation spread across 29 days, compared to just 49 mm (1.9 in) over 14 days in March. Humidity levels are somewhat similar, at 69% for May and 66% for March. For a more detailed breakdown of March weather in San Jose, you can check out San Jose weather in March.
The weather in May is characterized by slightly warmer temperatures compared to April, with a minimum of 14°C (58°F) and a maximum of 26°C (79°F), while April has a minimum of 13°C (56°F) and a similar maximum of 26°C (80°F). Both months share an average temperature of around 19°C (67°F), indicating a consistent warmth throughout. However, May experiences significantly higher precipitation, with 425 mm (16.7 in) spread over 29 days, compared to April's 113 mm (4.4 in) over 23 days. The humidity is also higher in May at 69%, compared to April's 67%. For more detailed insights, you can check San Jose weather in April.
In comparing the weather between May and June, we notice some interesting similarities and differences. Both months feature a minimum temperature around 14-15°C (58-59°F), with average highs peaking at approximately 26°C (79°F) in May and 26°C (78°F) in June. However, June experiences slightly less rainfall at 341 mm (13.4 inches) compared to May's 425 mm (16.7 inches), despite both months having similar precipitation days—29 for May and 28 for June. Additionally, June shows a noticeable increase in humidity, rising to 84% compared to May's 69%. Overall, both months offer warm temperatures, but June tends to be slightly drier and more humid. For more detailed insights, you can check San Jose weather in June.
In comparing the weather between May and July, we observe a slight increase in average temperature, with May showing a minimum of 14°C (58°F), an average of 19°C (67°F), and a maximum of 26°C (79°F). In contrast, July's temperatures range from a minimum of 15°C (59°F) to a maximum of 25°C (77°F). While both months experience considerable precipitation, May is significantly wetter, with 425 mm (16.7 in) falling over 29 days compared to July's 266 mm (10.5 in) over 28 days. Notably, July also experiences a higher humidity level at 85%, compared to May's 69%. For more detailed information on July weather, check out San Jose weather in July.
May and August share similar temperature ranges, with both months averaging around 19°C (67°F) and reaching maximums of 26°C (79°F). However, May tends to be wetter, receiving 425 mm (16.7 in) of precipitation over 29 days, compared to August’s 304 mm (12.0 in) across 28 days. Additionally, August experiences higher humidity, averaging at 82%, while May sits at 69%. For more detailed information, you can check San Jose weather in August.
Comparing the weather in May and September reveals some noticeable similarities and differences. Both months have a minimum temperature of 14°C (58°F) and an average temperature of 19°C (66-67°F), however, September’s maximum temperature is slightly lower at 25°C (78°F) compared to May’s 26°C (79°F). In terms of precipitation, May is notably wetter with 425 mm (16.7 in) of rainfall over 29 days, while September sees slightly less with 379 mm (14.9 in) also spread over 29 days. Additionally, September has a higher humidity level at 81%, compared to May's 69%. For a more detailed analysis of September's weather, you can visit San Jose weather in September.
May and October exhibit similar temperature ranges, with both months featuring a minimum of 14°C (58°F) and an average temperature around 19°C (66-67°F). However, October tends to be slightly cooler with a maximum of 25°C (78°F), compared to May's 26°C (79°F). Precipitation is notably higher in October, with 517 mm (20.4 in) falling over 29 days, while May sees 425 mm (16.7 in) of rain during the same number of days. Additionally, October boasts a higher humidity level at 80%, compared to May’s 69%. For a more detailed look at October weather, visit San Jose weather in October.
May and November both present mild temperatures in San Jose, but there are notable differences in their weather patterns. In May, the average temperature reaches 19°C (67°F), peaking at 26°C (79°F), while November's average is slightly cooler at 18°C (65°F), with a maximum of 24°C (75°F). Precipitation levels are significantly higher in May, with 425 mm (16.7 in) over 29 days compared to November's 260 mm (10.3 in) across 24 days, indicative of a wetter start to the year. Moreover, November experiences higher humidity levels at 80%, compared to May's 69%. For more specific insights about weather conditions, check San Jose weather in November.
In comparing May and December weather, we see noticeable differences in temperature and precipitation patterns. May experiences warmer temperatures, with averages around 19°C (67°F) and highs reaching up to 26°C (79°F), while December's temperatures are slightly cooler, averaging 18°C (64°F) with a maximum of 24°C (75°F). Precipitation also differs significantly, as May receives a considerable amount of rainfall at 425 mm (16.7 in) over 29 days, compared to December's 156 mm (6.1 in) over 16 days. Additionally, humidity levels remain relatively high in both months, with December being slightly more humid at 72% versus May's 69%. For more detailed insights, you can check San Jose weather in December.
As May ushers in the heart of the rainy season in San Jose, visitors can expect a delightful mix of warmth and moisture. While temperatures hover around a comfortable average of 19°C, the combination of higher humidity and increased rainfall—often seen with 29 days of precipitation—sets May apart from the drier months. This vibrant weather pattern not only nourishes the lush landscapes but also creates a refreshing atmosphere ideal for exploring the city's cultural offerings. For a deeper understanding of what to expect throughout the year, check out San Jose Climate.