A flash flood watch goes into effect at 6 p.m. on Saturday for the Big Island as Tropical Depression Wali treks toward Hawaii.
Deep tropical moisture associated with an upper-level trough will bring the threat of heavy rain and thunderstorms from Saturday night through 6 p.m. Monday, according to the National Weather Service in Honolulu. Showers are expected to reach the windward side of the Big Island on Saturday night.
The greatest chance of flooding will occur along the windward slopes, forecasters say. There is a lesser chance of flooding along leeward slopes.
A flash flood watch means that conditions may develop that lead lead to flash flooding, according to the service. Remember that it does not have to be raining heavily where you are for flash flooding to occur. The public is advised to avoid camping or hiking near streams of low-lying flood-prone areas.