Statewide Weather Update: Flood Watch and Rainfall Totals Across Hawaii

Current Weather System and Flood Watch Details

A surface trough shifting over the eastern half of the state continues to present a threat of minor flooding and ponding. Because of this unstable airmass and the potential for heavy rain, a flood watch remains in effect for Oahu, Molokai, Lanai, Maui, Kahoolawe, and Hawaii Island through early Thursday. Kauai is no longer included under the active watch advisory.

Meteorologists note that the airmass overhead is carrying double its usual amount of moisture. This elevated moisture content creates a higher capacity for heavier downpours and maintains a more humid environment across the region.

Rainfall Totals and Island Impacts

Heavy rain and thunderstorms have targeted Maui County and parts of Hawaii Island, including the Hamakua coast. On Molokai, rising waters led to flooded roads and prompted the closure of all local schools on Wednesday.

Despite these localized impacts, overall rainfall totals have proven beneficial. Molokai recorded the highest rainfall amounts, whereas Kauai received the least. Hawaii Island totals range from a trace up to roughly 3 inches in certain areas, though precipitation has not been uniform.

Forecasters point out that these rainfall totals are generally lower than original weather model projections. Because the upper-level jet and dynamics of the broad trough were less intense than anticipated, many neighborhoods experienced light drizzle rather than severe thunderstorms.

Forecast and Expected Improvements

Moderate to heavier showers alongside isolated thunderstorms are expected to persist along their current track through tonight. Lighter showers will likely focus on windward and mauka areas over the western end of the state.

Weather conditions are anticipated to improve by Thursday or Friday. A brief period of trade winds is projected to return late Friday into Saturday, followed by breezy northeast winds on Sunday as a shallow front approaches. Residents tracking forecasts for Halloween trick-or-treating should prepare for potentially wet conditions primarily limited to windward and mauka neighborhoods.

Sources: Hawaii News Now, KHON2, Honolulu Star-Advertiser.