...and more
In terms of precipitation, rainfall in San Juan ranges from 2.2 - 6.1 inches per month. November is typically the wettest month, when rainfall can reach 6.1 in. February is typically the driest time to visit San Juan when rainfall is around 2.2 in.
If weather is an important factor for your trip to San Juan, use this chart to help with planning. For those seeking warmer temperatures, June is the ideal time of year to visit, when temperatures reach an average of 82.4 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 77.0 F).