Moderate to locally breezy trades will prevail through the next several days, resulting in periods of shower activity across windward and mauka locations. An upper-level trough and developing low will slowly move eastward and become stationary northeast of the islands, enhancing clouds and shower activity. By the weekend, the upper-level trough is expected to dislodge and meander northeastward away from the state, however, periods of showers are expected to continue.
Issued at 324 AM HST Wed Apr 29 2026
Moderate easterly trade winds will continue with an upper level trough producing periods of MVFR conditions in passing showers mainly over windward mountain areas, and favoring the overnight to early morning hours. Terrain sheltered leeward areas along the western island slopes may see afternoon showers as sea breezes converge with trade winds each day.
No AIRMETs in effect. However, AIRMET Sierra may be needed later today for mountain obscurations mainly over north and east slopes of island mountains.
Issued at 930 AM HST Wed Apr 29 2026
Moderate to fresh east-northeast trades will continue today as a weak trough shifts to the west and a ridge builds north of the state. A Small Craft Advisory (SCA) has been issued for the typical windier waters surrounding Maui County and the Big Island. The SCA is likely to be extended through at least Friday before a trough approaches from the northwest this weekend, which will lead to a period of more relaxed trade winds.
A new northwest to north-northwest (320-330 degree) swell filling in today should increase surf along north and west facing shores through Thursday. Looking further ahead, a storm-force low currently in the North Pacific will send a moderate, longer-period northwest swell toward the islands for late Friday into Saturday, with above average surf expected along north and west facing shores. Average H1/10 heights for north facing shores is 6 feet for the month of May (Goddard-Caldwell Database).
Surf along south-facing shores will remain small through much of the week, with mainly background south to southwest swell expected. A small south-southwest pulse should arrive this weekend from recent activity east of New Zealand, providing an increase in surf.
Surf along east-facing shores will remain small and choppy through midweek, with a slight rise possible Thursday and Friday as trades strengthen.
Small Craft Advisory until 6 AM HST Thursday for Alenuihaha Channel-Big Island Leeward Waters-Big Island Southeast Waters- Maalaea Bay-Pailolo Channel.
