The National Weather Service in Honolulu forecasts strengthening trade winds over the weekend, reaching moderate to breezy levels. A low-level trough tied to the remnants of former Tropical Cyclone Ivo is expected to move across the Hawaiian Islands on Sunday, bringing increased cloud cover and showers to windward and mauka areas through Monday. Conditions are projected to turn drier and more stable by Tuesday as high pressure reestablishes over the region.
The forecast discussion notes that a satellite-imaged trough northwest of Kauai is moving out of the area, allowing high pressure and stronger trade winds to build. Model guidance shows some differences regarding the trough’s impact, with one suggesting it will centralize over the islands and bring wetter conditions, while another projects a northern pass that would limit shower activity mainly to Oahu and Kauai. Both outcomes depend on higher-resolution model data as the system approaches. In terms of aviation, moderate trade winds are expected to strengthen following the trough’s exit, with “brief periods of MVFR conditions in clouds or shower activity” along windward and mauka areas, while VFR conditions are expected elsewhere, the NWS details.
A Small Craft Advisory (SCA) is in place through Sunday morning, alerting mariners of the expanding brisk easterly trades that could extend the advisory further. The marine forecast sees trades tapering off by Monday as Ivo’s remnants cross over, only to swiftly regain strength by late Monday. The south-southwest swell remains steady, producing average surf levels, and is expected to stay below advisory thresholds. Similar swells are forecast early to mid next week, as reported by NWS…