Area Forecast Discussion
Issued by NWS Honolulu, HI
Issued by NWS Honolulu, HI
509 FXHW60 PHFO 031345 AFDHFO Area Forecast Discussion National Weather Service Honolulu HI 345 AM HST Thu Jul 3 2025 .SYNOPSIS... Dry conditions will prevail within better established trade winds. Breezy winds will strengthen to locally windy through the holiday weekend. Thicker clouds and higher shower frequency remain focused over primarily windward exposures and upslope mauka during the overnight hours. && .DISCUSSION... A near 1030 mb high will settle a little over a thousand miles north northeast of the island chain the next several days. This will tighten the downstream pressure enough across the state to produce and maintain breezy to locally strong trade winds through the 4th of July holiday weekend. After this early morning pocket of moisture passes by the eastern third of the state, there will be many days where the suppressing mid level ridge takes over, rooting itself over and north of the islands. This will result in a significantly dry mid to upper level regional atmosphere. A more shallow nocturnal boundary layer will only be sufficiently moist enough to produce showers due to upslope forcing brought about by enhanced trades. Trades should generally become strong enough to overcome any mentionable local scale breeze behavior. Sunnier skies as a result of stable mid to upper ridging producing a drier (overall) column will still occur, especially over better wind protected areas (such as leeward Big Island), building afternoon clouds and introducing more frequent afternoon showers. The combination of drier conditions within breezy to locally strong trade flow will elevate fire weather concerns, particularly each subsequent mostly sunny day without any substantial rainfall. Many windward areas are abnormally dry with leeward regions falling under more moderate drought conditions. Confidence remains low but, if the state does experience a near term period of low to nil rain, the main topic of concern the next few days will be centered around greater wildfire potential. && .AVIATION... Moderate to locally breezy trade winds expected through the next several days. Low cigs and SHRA should mainly impact windward and mauka slopes. We could see some iso showers spill over into leeward areas. MVFR conds possible in SHRA otherwise VFR prevails. AIRMET Tango is not in effect but may be need for mod turb due to the trades later today. && .MARINE... High pressure far north of the state will strengthen Friday into the weekend with fresh to locally strong trade winds expected. Winds are expected to further strengthen early next week with widespread strong trade winds possible. A Small Craft Advisory (SCA) is in effect for the typical windier waters and channels around Maui County and the Big Island starting at 6 AM today and continuing through at least 6 PM Friday. The current south swell will slowly decline Friday into the weekend. Surf heights should still hold near the summer time averages before dropping Friday into the weekend. Tiny, long- period south swell energy will hold into next week, with below average surf expected. Along east facing shores, an increase of rough and choppy surf is expected this weekend into next week as the trade winds strengthen. No significant swells are expected through next week. && .HFO WATCHES/WARNINGS/ADVISORIES... Small Craft Advisory until 6 PM HST Friday for Maalaea Bay- Pailolo Channel-Alenuihaha Channel-Big Island Leeward Waters-Big Island Southeast Waters. && $$ DISCUSSION...Blood AVIATION...Walsh MARINE...Walsh