Breezy trades expected through the middle of next week. An upper level trough and moisture associated with the remnants of Norbert will fill in across the state from east to west Thursday into Friday, increasing the chances of heavy rain, isolated thunderstorms, and flash flooding, especially for the windward and mauka areas. Drier air will move back in this weekend behind the departing trough. Moisture from the remnants of Tropical Depression 15-E may bring another round of enhanced trade showers around next Tuesday and Wednesday.
The remnants of Norbert in the form of an approaching easterly trough will pass across the islands through early Friday. Higher moisture accompanying this trough will introduce a greater frequency of showers and/or brief periods of light rain. Decks will lower into MVFR categories during times of rain or passing light to moderate intensity showers. Typically breezy trades through the period with wind sheltered areas remaining light and variable.
AIRMET SIERRA is in effect for island-wide mountain obscuration.
A broad trough, associated with the remnants of Tropical Storm Norbert, will approach the state from the east tonight, allowing moderate to locally strong northeast trades to hold through tonight. This afternoon ASCAT pass showed borderline Small Craft Advisory (SCA) conditions around Maui County and the Big Island leading to less confidence that SCA conditions will hold as the trough passes over the state Thursday, thus have not extended the SCA at this time. After the trough moves through the state Thursday into Friday, a surface high far northeast of the state could allow moderate to locally strong trades to return over the weekend through the forecast period. Above normal moisture and upper level support will allow isolated thunderstorms with localized heavy rain and gusty outflows to develop over the offshore waters tonight through Saturday.
A series of long to medium period south-southwest to south swells will continue fill tonight. Surf along south facing shores should begin to see more consistent sets tonight into Thursday as build to near average. A reinforcing southerly swell will fill in Friday bumping surf near High Surf Advisory thresholds by this weekend as swells shift more out of a south direction.
Surf along east- facing shores increases today into Thursday as trade winds strengthen and a small, medium- period east swell from the remnants of Norbert arrives. Flat to tiny surf along north facing shores is expected through the forecast period.
Flood Watch through late Thursday night for Big Island East-Big Island Interior-Big Island North-Big Island South-Big Island Southeast-Big Island Summits-Central Oahu-East Honolulu-Ewa Plain-Haleakala Summit-Honolulu Metro-Kahoolawe-Kauai East-Kauai Mountains-Kauai North-Kauai South-Kauai Southwest-Kipahulu- Kohala-Kona-Koolau Leeward-Koolau Windward-Lanai Leeward-Lanai Mauka-Lanai South-Lanai Windward-Maui Central Valley North-Maui Central Valley South-Maui Leeward West-Maui Windward West- Molokai Leeward South-Molokai North-Molokai Southeast-Molokai West-Molokai Windward-Niihau-Oahu North Shore-Olomana-South Haleakala-South Maui/Upcountry-Waianae Coast-Waianae Mountains- Windward Haleakala.
Small Craft Advisory until 6 AM HST Thursday for Alenuihaha Channel-Big Island Leeward Waters-Big Island Southeast Waters- Maalaea Bay-Pailolo Channel.
