RIO DE JANEIRO – New rains in waterlogged southern Brazil are expected to be heaviest between Sunday and Monday, authorities have warned, bringing fresh misery to victims of flooding that has killed 136 people so far.State authorities warned late Saturday of the risk of further rising waters and landslides.”We are still experiencing an emergency situation,” Rio Grande do Sul Governor Eduardo Leite said in a video on Instagram.Heavy rains last week caused rivers in the agricultural state to overflow, leaving 806 injured and 125 missing in addition to those killed, the civil defense agency…