Area Forecast Discussion
Issued by NWS Honolulu, HI
Issued by NWS Honolulu, HI
440 FXHW60 PHFO 031302 AFDHFO Area Forecast Discussion National Weather Service Honolulu HI 302 AM HST Wed Sep 3 2025 .SYNOPSIS... Light to moderate trade winds will produce mostly light showers over windward and mauka areas into the weekend. Most leeward areas will continue to be rather dry, except the Kona slopes of the Big Island where scattered showers will develop each afternoon. && .DISCUSSION... Looking at satellite and radar this morning, some isolated showers continue moving across the region with some low clouds riding in on the trades. No major changes are expected to the forecast. A subtropical ridge sitting about 250 miles north of the islands and continues to be weakened by an area of low pressure farther to the north. A ridge aloft is producing stable and dry conditions. Trades expected to remain stable and in the light to moderate range through the weekend. Guidance has been hinting at a band of moisture moving through Saturday night or Sunday, which could lead to a brief boost in windward and mauka showers. Heading into the middle of next week, forecast uncertainty increases due to the passage of Hurricane Kiko over the region. Given uncertainty at this time, it remains too early to tell what, if any, impacts this system will have on local weather. && .AVIATION... Light to moderate trades expected for the next few days. Low cigs and isol SHRA possible over windward and mauka areas. MVFR conds in SHRA otherwise VFR prevails. No AIRMETS are in effect. && .MARINE... A weak surface ridge to the north will remain nearly stationary through the forecast period. This will maintain moderate to locally fresh trade winds with some localized sea breezes, especially across leeward waters. Surf along north facing shores will gradually decline today as a mix of the north and northwest swells fade through Thursday. Reinforcing small short- to medium-period north-northwest swells are expected through the end week which will keep surf from going flat. In the extended forecast, the northwest Pacific looks to get active as low pressure systems traverse the basin over the weekend sending the potential for a few small to moderate swells during the middle of next week. Surf along south facing shores will see background medium- to long- period energy through the week before a small to moderate long- period south-southwest swell fills, and peaks over the weekend. Below average surf is expected to continue along east facing shores through the rest of the week. In the extended forecast, easterly energy from Hurricane Kiko in the Eastern Pacific is expected early next week that could potentially bring surf to near High Surf Advisory (HSA) criteria. Peak monthly high tides, combined with water levels running higher than predicted, may lead to minor flooding along the shoreline and in low-lying coastal areas. A Coastal Flood Statement has been issued through Sunday afternoon. && .FIRE WEATHER... Light to moderate trade winds will remain below the critical fire weather thresholds through at least the weekend. Dry and stable conditions will prevail, with afternoon relative humidity dropping to around 45 percent each afternoon through Saturday. && .HFO WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...Walsh AVIATION...Walsh MARINE...Shigesato FIRE WEATHER...Walsh