Area Forecast Discussion
Issued by NWS Honolulu, HI
Issued by NWS Honolulu, HI
073 FXHW60 PHFO 091320 AFDHFO Area Forecast Discussion National Weather Service Honolulu HI 320 AM HST Wed Jul 9 2025 .SYNOPSIS... An area of strong high pressure will begin to weaken and lift northeast of the islands today. Trades will weaken slightly as a result of the eased pressure gradient. Expect passing showers encapsulated within a band of fairly stable clouds today, leading up to more typical trade shower activity for windward and mauka areas for the remainder of the week. && .DISCUSSION... An area of strong high pressure responsible for maintaining breezy to strong trades will begin to weaken and lift northeastward, easing the local pressure gradient. As a result, trades will slightly weaken through the remainder of the week. While trends are showing weakening, brief periods of stronger winds may still remain in wind-prone locations. However, latest observations, including across the summits, have begun to show this decrease, as overall trades are expected to be moderate to locally breezy beginning today. As trades weaken, fire concerns will also be on the decline. Expect humidity levels rebound back above criteria levels and the local KBDI value at Honolulu remains below the 600 threshold. While conditions are not favorable for fire concerns, it is worth noting that any unintentional spark could lead to a fire and to remain vigilant when recreating outdoors during this transition period. Latest satellite observations also showcase some passing showers encapsulated within a band of fairly stable clouds moving west to east into the windward and mauka areas. Pockets of moisture will likely be escorted by these trades, bringing periodic shower activity to windward and mauka areas through the remainder of the week. && .AVIATION... Moderate to locally breezy trades persist through the day under predominately stable conditions. Passing showers favoring windward and mountain areas may lead to brief MVFR conditions. Otherwise, VFR conditions will prevail. AIRMET Tango remains in effect for moderate low-level turbulence over and downwind of island terrain. && .MARINE... High pressure far northeast of the islands will support fresh to strong trades across the area. A Small Craft Advisory (SCA) is now in effect for all Hawaiian coastal waters through 6 AM HST Wednesday. The surface high will move eastward and weaken slightly during the second half of the week, but winds are likely to remain breezy to locally strong in the windier channels and waters of Maui County and the Big Island through the rest of the week. A SCA is in effect from 6AM Wednesday through 6AM Thursday for the typical windier waters around Maui and the Big Island. A small mid-period south swell will continue through Thursday. A slight boost to the period expected on Saturday. Another small, long- period swell expected next Sunday night into Monday. Surf along south facing shores will boost along with the arrival of the mentioned swells. Surf along east-facing shores will be rough and choppy due to the breezy trade winds that will persist the rest of the week. && .HFO WATCHES/WARNINGS/ADVISORIES... Small Craft Advisory until 6 AM HST early this morning for Kauai Northwest Waters-Kauai Windward Waters-Kauai Leeward Waters- Kauai Channel-Oahu Windward Waters-Oahu Leeward Waters-Kaiwi Channel-Maui County Windward Waters-Maui County Leeward Waters- Big Island Windward Waters. Small Craft Advisory until 6 AM HST Thursday for Maalaea Bay- Pailolo Channel-Alenuihaha Channel-Big Island Leeward Waters-Big Island Southeast Waters. && $$ DISCUSSION...Pierce AVIATION...Pierce MARINE...Walsh