The National Weather Service (NWS) reports that Honolulu can expect an increased likelihood of rainfall as a band of unstable clouds moves in with the trade winds. The heightened shower activity is anticipated to continue from this morning through tomorrow. Simultaneously, the ongoing Kilauea eruption continues to pose a risk of localized ashfall and increased vog on the Big Island. The NWS has published a Special Weather Statement on their website for further details.
While the trade winds are set to usher in showers, particularly on the windward sides of the islands, the weakening of these winds will allow for lighter, east to southeast flows beginning tomorrow. This shift in wind direction could lead to the development of land and sea breezes in sheltered areas into the upcoming weekend. A temporary lapse in wind strength paves the way for thermally driven breezes to dictate local weather patterns, with afternoon showers likely in the interior and upslope areas before clearing at night.
In terms of aviation, the ongoing conditions include moderate trade winds. As per the NWS report, "Moderate trades through the forecast period. Low cigs and SHRA should be mainly focused over windward and mauka locations. MVFR conds possible in any SHRA otherwise VFR will prevail." Additionally, Kilauea's eruption, now in its 34th episode, may lead to possible ashfall and an ash cloud that could reach up to 25,000 feet, with SIGMET Series Whiskey in effect for volcanic ash.
On the marine front, moderate trades are expected for the next few days, sustained by surface high pressure to the north. However, the NWS notes that the pressure gradient will be disrupted as a trough moves northwest of the state by Friday, resulting in weaker winds. In addition, surf conditions on the north and west shores are set to intensify, with waves building to well over head high by Sunday due to a northwest swell.
The risk of fire remains low throughout the state as wind speeds are forecasted to stay below critical thresholds. The temperature inversion heights are also stable, ranging from 7,000 to 8,000 feet across the islands. Currently, there are no HFO Watches, Warnings, or Advisories in effect for the region.
