Area Forecast Discussion
Issued by NWS Honolulu, HI
Issued by NWS Honolulu, HI
322 FXHW60 PHFO 031327 AFDHFO Area Forecast Discussion National Weather Service Honolulu HI 327 AM HST Mon Nov 3 2025 .SYNOPSIS... As the surface level trough and upper-level low move away from the islands, weak ridging will fill the void aloft well north of the state. Shower trends will decrease a bit from Tuesday into Thursday as a result. Towards the end of the week, an upper-level trough will drop in on Friday and bring some enhanced trade wind showers ahead of another, weaker cold frontal boundary advancing southward into the western islands by this weekend. && .DISCUSSION... A trough, formerly the southward advancing cold frontal boundary, and accompanied upper-level low immediately behind the trough now sit west of Kauai and are progged to continue westward away from the Hawaiian Islands throughout the day. With it, much of the moisture has also vacated to the west and away from the western islands. Remnant isolated showers persist around the state, producing little to no precipitation. As the aforementioned trough and upper-level low exit the vicinity of the islands, upper- level ridging will gradually rebuild north of the state, opening the doors for moderate trades to reestablish beginning Tuesday and prevail through the next couple of days. Later today, a pocket of tropical moisture will extend north, clipping the Big Island, and bring enhanced shower activity to windward and southeast slopes. Heaviest of showers will be focused over windward Big Island, however, the typical trade wind pattern will likely bring periods of showers to windward and mauka areas on all other islands as well. Thereafter, latest deterministic models suggest another upper- level trough will advance southward toward the islands, escorted by yet another, weaker cold frontal boundary. Models are projecting that the frontal boundary will approach the islands by the middle of the weekend and stall out within the proximity of Kauai and Oahu. Much like this recent cold frontal boundary, as this one reaches the islands, expect increased cloud coverage and enhanced shower activity to the surrounding islands, as well as a period of relatively gusty winds. && .AVIATION... Moderate trades will continue for the next couple of days as ridge builds north of the state. Upper to mid level clouds are streaming in from the southwest to northeast across the eastern half of the state from a rather active ITCZ. An upper level low will continue to move westward allowing for drier and stable conditions to build in. Expect mostly VFR conditions today. The exception could be along southeast and Kona portions of the Big Island where a plume of moisture is pooling along that area and could generate MVFR conditions due to cld and shra as seabreezes develop. No AIRMETs are in effect. AIRMET SIERRA may be need later today for portions of the Big Island for MVFR ceilings from mountain obscuration. && .MARINE... A trough and upper level disturbance west of Kauai leeward waters will continue to drift westward today, decreasing shower activity statewide. Gentle to fresh trade winds will strengthen slightly into the fresh to locally strong range from Tuesday through Thursday. Seas in excess of 10 feet will continue today for the northwestern coastal waters, and then decline below Small Craft Advisory levels by tonight. The SCA remains in effect for these waters due higher seas through this afternoon. The High Surf Advisory was cancelled this morning as the north- northwest swell continues to decline just below advisory levels today. Looking into the swell future we see pulses of medium and long period swell energy continuing from the northwest to north direction through much of next week. The next north-northwest moderate swell build into the region starting late Tuesday, peaking by Wednesday, and then declining. A brief, overlapping small long period northwest (320 deg) swell will build in from Wednesday night through Thursday. The next moderate to large, medium period northerly (350-020 deg) swell builds into the region from late Friday, peaking on Sunday above advisory levels, before gradually declining into the first half of next week. Another longer period northwest (320-330 deg) swell arrives in time for the middle period of next week. Surf along east and south facing shores will remain small into next week. Only slight pulses of long period south swell energy are expected over the next seven days. Bust out your long boards. && .FIRE WEATHER... Increased relative humidity values and light to moderate trades will maintain below critical fire weather conditions the next several days. Temperature inversion heights near the Big Island and Maui will range from 7,500 to 8,500 feet today. && .HFO WATCHES/WARNINGS/ADVISORIES... Small Craft Advisory until 6 PM HST this evening for Kauai Northwest Waters-Kauai Windward Waters-Kauai Leeward Waters- Kauai Channel-Oahu Windward Waters. && $$ DISCUSSION...Pierce AVIATION...Almanza MARINE...Bohlin FIRE WEATHER...Pierce