HONOLULU -- The National Weather Service on Monday issued a flash flood watch for all of the Hawaiian Islands to start on Tuesday night and last through Thursday.

A disturbance west of Kauai is forecast to move over the islands Wednesday and Thursday, it is likely to bring some unsettled weather, including the chance for heavy rains and flash flooding.

The instability may favor the Big Island's Kona slopes, enhancing a slight chance of isolated thunderstorms.

Forecasters also issued the first winter storm watch of the season. The advisory is to start on Wednesday morning and will last through Thursday morning for Mauna Loa dn Mauna Kea above the 12,000-feet level.

There is a chance of heavy snowfall, forecasters said.

Stay with KITV and KITV.com for updates on the developing weather forecast.