In terms of precipitation, rainfall in Portland ranges from 0.8 - 3.9 inches per month. June is typically the wettest month, when rainfall can reach 3.9 in. February is typically the driest time to visit Portland when rainfall is around 0.8 in.
If weather is an important factor for your trip to Portland, use this chart to help with planning. For those seeking warmer temperatures, February 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 48.2 F).