The appearance of "murky reddish water and powerful, swift currents" is a critical early warning sign of a flash flood, usually caused by heavy accumulated rainfall in the upstream forests of Khao Yai National Park. Visitors are strongly advised to exit the water immediately and stay far away from the stream banks, as water levels can rise abruptly and carry dangerous debris like fallen branches or large rocks. During such conditions, park rangers typically prohibit swimming and may close certain areas for safety; therefore, it is essential to strictly follow official warnings, whistles, or flags until the water stabilizes and regains its clarity.