Taking the local weather in Balneário Martinez into account is an important factor for planning your visit, especially if you plan to spend your trip by the pool. The hottest months are usually February and January, with an average temperature of 25°C, while the coldest months are July and August, with an average of 20°C. The rainiest months in Balneário Martinez are January, February, March and December, with each month seeing an average of 278 mm of rainfall.