In terms of precipitation, rainfall in Nelson ranges from 2.8 - 3.1 inches per month. May is typically the wettest month, when rainfall can reach 3.1 in. January is typically the driest time to visit Nelson when rainfall is around 2.8 in.
If weather is an important factor for your trip to Nelson, use this chart to help with planning. For those seeking warmer temperatures, January is the ideal time of year to visit, when temperatures reach an average of 62.6 F. Travelers looking to avoid the cold should look outside of July, when temperatures are typically at their lowest (around 44.6 F).