San Juan Weather in May

The climate in San Juan during May can be summarized as hot, humid and reasonably dry.

May is in the spring in San Juan and is typically the 5th warmest month of the year. Daytime maximum temperatures average around a steamy 32°C (90°F), whilst at night 22°C (72°F) is normal.

On average May is the 2nd wettest month of the year in San Juan with around 77mm 3 inches of rain making it a reasonably dry time to visit. This rainfall is typically spread over 4 days, although this may vary considerably.

On the flip side this corresponds to an average of 8 hours of sunshine per day.

The data used in these monthly averages covers a period of over 100 years right up until last year. As such they are a valid prediction of what to expect for the weather in San Juan in May 2025.