


Area Forecast Discussion
Issued by NWS Honolulu, HI
Issued by NWS Honolulu, HI
622 FXHW60 PHFO 120129 AFDHFO Area Forecast Discussion National Weather Service Honolulu HI 329 PM HST Sat Oct 11 2025 .SYNOPSIS... A surface trough just to the north of the state will help bring relatively light winds today. A significant upper level low approximately 1000 miles north of the islands will move south through midweek. Models indicate it could move very close to or perhaps even over the state. This will increase instability and introduce a chance for stronger showers and a few thunderstorms. East to southeast surface winds continue, becoming stronger from Wednesday into next weekend. && .DISCUSSION... Relatively light surface winds have allowed sea breezes to develop again today, although not as strong as yesterday. Isolated to scattered showers were developing statewide as of 3 PM HST. These are forecast to last into the early evening hours before diminishing rapidly after sunset. A strong upper level low dropping south toward the state will help determine our weather for the coming week. As this low approaches and brings cooler air aloft, the atmosphere will become increasingly unstable. Low-level moisture is also forecast to increase Monday. These factors will combine to favor a few stronger showers and most likely a few thunderstorms after Tuesday. Thunderstorms may develop as early as Tue night, but probably not until Wednesday/Thursday. Conditions will remain favorable for thunderstorms through at least Friday. Models do have some important differences in timing/location of this feature, so we agree with the previous forecast in not attempting to nail down exact thunderstorm locations this early. However, confidence is increasing that at least a few thunderstorms will form next week (most likely over the western half of the state). && .AVIATION... A trough north of the state is resulting in light E to ESE winds across the island chain today. For some locations, this has resulted in variable winds, switching between easterly trades and onshore sea breeze winds. Clouds and showers remain limited overall, though some clouds and showers will remain possible through early evening over island interiors and select leeward locations. VFR flight conditions are expected to prevail for most areas. This same pattern will persist into Sunday, with light background winds and sea breezes increasing interior clouds and showers during the day. Overnight, land breezes are forecast to diminish cloud cover over the islands. There are currently no AIRMETs in effect, and none are anticipated at this time. && .MARINE... Broad troughing north of the islands will keep the local pressure gradient somewhat weak, maintaining mainly gentle to moderate trade winds over coastal waters into Tuesday. The trough will gradually fill late Tuesday and Wednesday, and building surface high pressure north of 30N will drive strengthening trade winds. Small Craft Advisory conditions may develop over the typically windy waters around the Big Island and Maui as early as Wednesday night and likely by Thursday. As trades strengthen, a disturbance aloft will drift southward over the islands and bring instability. Small north shore surf today will give way to a long lived event Sunday. Currently, a mix of building medium period northwest swell and short- to medium-period north-northeast swell is producing small surf along north facing shores. The north- northeast swell will fade tonight as the northwest swell picks up slightly. Long-period forerunners of a new northwest (320 deg) swell will build on Sunday, and surf should peak at High Surf Advisory levels Monday and Tuesday for most north and west shores from Kauai to Maui. Surf will gradually decline Thursday and Friday, with some small northwest swell lingering into next weekend. Small inconsistent southwest swell will decline by Monday, with tiny background swell prevailing through the rest of the week. Along east facing shores, the small north-northeast swell will fade overnight, but a slight increase to near seasonal normal is expected tonight into Monday as medium-period easterly swell from a distant tropical cyclone moves across the area. Low swell energy from the east is already on the rise at the Hilo PacIOOS buoy and should slowly build overnight. East shore surf will be small Tuesday, then increase and become rough during the second part of the week as trade winds build over and upwind of the islands. Water levels during morning high tides will continue to gradually lower during the next couple of days. Since water levels peaked just below the flooding level at most stations today, the Coastal Flood Statement has been canceled. However, conditions will be borderline at the Honolulu station Sunday morning. && .FIRE WEATHER... Light winds and isolated to scattered showers will help maintain fire weather below critical thresholds for the next several days. Inversion heights will range from 7,000 to 8,500 feet. && .HFO WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...Parker AVIATION...Vaughan MARINE...Wroe FIRE WEATHER...Parker