A Flash Flood Watch for Niihau, Kauai and Oahu through Wednesday (4PM) and a Flash Flood Advisory for Oahu until 9:15AM Tuesday. Heavier showers and isolated thunderstorms are expected to continue for majority of the day, showers could be affecting Maui county by the afternoon. Variable winds below 10 MPH and temperature highs 85-90 degrees. Lows 72-77 degrees. Box jellyfish for South and East facing shores today. East 2-3', West and South 1-2', North 1-3'.