Area Forecast Discussion
Issued by NWS Honolulu, HI
Issued by NWS Honolulu, HI
659 FXHW60 PHFO 141414 AFDHFO Area Forecast Discussion National Weather Service Honolulu HI 414 AM HST Sat Jun 14 2025 .SYNOPSIS... Trade winds will persist through the next several days and will be breezy and gusty Saturday through Tuesday. Showers will be focused along typical windward and mauka areas, as well as the Kona slopes of the Big Island each afternoon. && .DISCUSSION... Typical summertime trade wind weather is expected to persist through next week, with only subtle variations expected through the forecast period. This morning`s radar and satellite imagery show a slight uptick and clouds and showers riding in on the trades, most of which are being confined to windward and mauka areas under a strong inversion, as seen in the 2 AM HST upper air soundings. A weak upper level trough/low will remain near the western end of the state through weekend, but isn`t expected to have much of an impact on local weather, except for potentially increasing the chance of rain over Kauai. Surface high pressure to our north is currently being split by a front passing through the northeast Pacific. Even so, model guidance indicates that this split high will gradually strengthen, causing the the local pressure gradient to tighten and bring breezy and gusty easterly trades to the island chain this weekend. These breezy to gusty trades will persist into early next week, or perhaps slightly strengthen, as the split high to the north consolidates into one to our far northeast and builds. At the same time, mid to upper level ridging will build overhead and remain there through the rest of the forecast period, maintaining a stable trade wind pattern. As such, clouds and showers are expected to continue to favor the typical windward and mauka areas, particularly during the overnight to early morning time periods. && .AVIATION... Moderate to breezy trade winds will gradually strengthen this weekend and continue to focus incoming low clouds and showers over windward and mauka areas. Brief MVFR ceilings and visibility will be possible in any showers. Otherwise, VFR conditions are expected to prevail. AIRMET Sierra for tempo mountain obscurations is in effect through the early morning hours for windward portions of the smaller islands. AIRMET Tango is posted for tempo moderate turbulence leeward of mountains across all islands. This will likely continue through the weekend as trade winds strengthen. && .MARINE... High pressure north of the region will strengthen and dominate through the forecast period. As a result, trade winds will strengthen a notch through the rest of this weekend and remain through next week. A Small Craft Advisory (SCA) for the windier waters and channels around Maui County and the Big Island remains in effect through Monday, but will likely need to be extended and possibly expanded in coverage as the trades strengthen. Surf along south facing shores will be small through today. A series of small, long period, south swells originating from fetches near New Zealand will help boost surf heights near the summer average (5 feet) throughout next week. The first boost should fill in Sunday into Monday, followed by another bump Wednesday into Thursday of next week. Rough and choppy surf along east facing shores are expected to slightly increase this weekend into early next week due to trade winds strengthening. Surf will remain at seasonable levels (nearly flat) along north facing shores throughout the forecast period. Some select exposures could see some tradewind swell wrap. && .HFO WATCHES/WARNINGS/ADVISORIES... Small Craft Advisory until 6 PM HST Monday for Maalaea Bay- Pailolo Channel-Alenuihaha Channel-Big Island Leeward Waters-Big Island Southeast Waters. && $$ DISCUSSION...Farris AVIATION...Farris MARINE...Tsamous