Moderate to breezy trade winds will strengthen through the week and deliver showers to windward and mountain areas.
Light shower activity will continue to wane through the morning, however periodic MVFR remains possible across windward sites so long as shower activity persists. Moderate trades are expected through the forecast period, with skies partially clearing across the islands by the afternoon.
AIRMET Sierra is in effect for the windward Kauai, Oahu, and Maui due to low clouds from ongoing showers. Conditions, however, are expected to improve by the afternoon.
High pressure far northeast of the state will maintain fresh to locally strong trades through tonight. A Small Craft Advisory (SCA) remains in effect for the typical windier channels and waters around Maui and the Big Island for the strengthening trade winds. Trades are expected to strengthen another notch Thursday into Friday as a 1036 mb high develops far north of the state. Widespread fresh to strong winds are expected during this time with near gales possible for the windier waters around Maui County and the Big Island. The SCA will be expanded to other area waters as the trades pick up later this week. The strong high to the north is expected to eventually shift westward and weaken some, which should allow the trade winds to weaken a notch around Sunday. Trends in the strength and direction of winds early next week become less clear as a result of the uncertain track of a weakening Hurricane Fausto (forecast to become a tropical storm by Monday) in the central Pacific.
The current medium-period south-southeast swell producing above average surf along south-facing shores will continue to gradually fade over the next few days, allowing surf to diminish somewhat this afternoon after this morning's bump in south shore surf. Offshore buoys are showing an increase in 23 second energy this morning as forerunners from the next notable incoming south swell slowly fill in throughout the day today. This will allow surf to increase again tonight into Thursday and peak above advisory thresholds and possibly approaching warning levels late Thursday into Friday. Over the weekend, reinforcing long-period swell energy may allow advisory level surf to persist.
Surf along east-facing shores will remain slightly below seasonal levels through the evening due to the weaker trades upstream of the islands. The Hilo buoy continues to show a small, medium- period east swell this evening, which was likely generated by former TC Elida. Stronger trade winds will also support an increase of short-period energy heading into Thursday and Friday. This weekend, larger surf generated by Hurricane Fausto is possible and could bring advisory level surf along east facing shores.
Surf along north-facing shores will remain at flat to tiny levels through the weekend.
Small Craft Advisory until 6 AM HST Thursday for Alenuihaha Channel-Big Island Leeward Waters-Big Island Southeast Waters- Maalaea Bay-Pailolo Channel.
