In terms of precipitation, rainfall in Barreiras ranges from 0.0 - 7.4 inches per month. December is typically the wettest month, when rainfall can reach 7.4 in. July is typically the driest time to visit Barreiras when rainfall is around 0.0 in.
If weather is an important factor for your trip to Barreiras, use this chart to help with planning. For those seeking warmer temperatures, September is the ideal time of year to visit, when temperatures reach an average of 78.8 F. Travelers looking to avoid the cold should look outside of June, when temperatures are typically at their lowest (around 71.6 F).