Another southwestern Indiana county has joined the list of area counties to impose an outdoor burn ban. Martin County issued a burn ban Thursday, joining Gibson, Posey, Vanderburgh, Warrick and Spencer Counties. The ban is due to continuing dry conditions that could lead to flash fires. Lawrence County here in southeastern Illinois also has imposed a burn ban. The Illinois Drought Monitor released this week indicates that parts of Lawrence and Wabash Counties are considered to be abnormally dry.