A weakening high pressure ridge north of the Hawaiian Islands will keep trade wind speeds on the decreasing trend lasting into Saturday, then ridge and wind speeds strengthen from Saturday afternoon into early next week. Passing showers are possible over windward and mountain areas during this time period, mainly during the overnight to early morning hours. The next best chance for statewide rainfall may develop from Monday into Tuesday of next week, as the cloud remnants from an old cold front drift across the islands on the trade winds.
Trade winds will continue with brief periods of passing showers over windward and mountain areas favoring the overnight to early morning hours. Improving weather trends during the daylight hours.
AIRMET Sierra may be needed for mountain obscurations later tonight.
AIRMET Tango remains in effect for low level moderate turbulence over and downwind of island mountains.
A high pressure system north of Hawaii will slowly weaken through Saturday, allowing trade winds to slightly decrease tonight. A Small Craft Advisory (SCA) remains in effect for the typical windy waters near Maui County and the Big Island. By Saturday evening, a new high pressure will build north of the islands and restrengthen trade winds, likely leading to an expansion of the SCA to include additional waters. Next week will likely see continuing fresh to strong trades with some minor fluctuations each day. A moderate to large north-northwest swell is also expected to fill in early Sunday morning and elevate seas above 10 feet for coastal waters.
A moderate, north-northwest swell will continue to decline tonight into the weekend, allowing surf to become moderate to small and then small. A new small, north-northwest swell will support continued small surf into Saturday before the arrival of a more significant north swell. This moderate, long-period north swell arriving Saturday night may bring surf to advisory levels on Sunday for north and west- facing shores. Surf to at least moderate levels will last into Monday before the swell really begins to fade on Tuesday. A small to moderate northwest swell is then possible by next weekend.
Surf along east-facing shores will decrease slightly tonight and Saturday as trades ease early this weekend. Surf will increase again Sunday into early next week as trades restrengthen. South shore surf will stay tiny to small for the next few days, then a small, long-period swell could boost surf heights towards the end of next week.
Small Craft Advisory until 6 PM HST Saturday for Alenuihaha Channel-Big Island Leeward Waters-Big Island Southeast Waters- Maalaea Bay-Pailolo Channel.
