First Alert Weather: Kauai, Oahu under flood watch as unstable system develops

HONOLULU (HawaiiNewsNow) - A flood watch has been issued for the islands of Kauai County and Oahu from noon Tuesday until 6 p.m. Wednesday as an unstable system develops rapidly to the west of the state.

Heavy showers and isolated thunderstorms are expected to increase Tuesday afternoon and continue into Wednesday.

Periods of heavy rainfall will be possible over leeward and windward communities of Kauai and Oahu.

The National Weather Service in Honolulu said a stationary frontal boundary is about 300 miles west of Kauai, along with a large low pressure area about 700 miles to the northwest.

This system has caused a southerly wind flow, which is drawing up an area of deep tropical moisture over the islands, with bands of heavy rain and thunderstorms.

The storm system is expected to remain just away from the islands. However, forecasters said a difference of just 50 to 100 miles in its location could result in stronger impacts on weather conditions.