Area Forecast Discussion
Issued by NWS Honolulu, HI
Issued by NWS Honolulu, HI
807 FXHW60 PHFO 240133 AFDHFO Area Forecast Discussion National Weather Service Honolulu HI 333 PM HST Sat Nov 23 2024 .SYNOPSIS... Light winds and mostly dry weather will generally prevail, but a weak front moving over the area will bring a chance of showers Sunday afternoon through Monday, mainly to windward portions of Kauai and Oahu. A brief period of moderate trade winds is possible around the middle of the week, with winds potentially diminishing by the end of the week. && .DISCUSSION... Light winds and mostly dry weather will prevail this coming week, with a couple of exceptions. A weak front moving over the islands from the N will bring a chance of showers from Sunday afternoon through Monday, mainly to N and E facing slopes and coasts of Kauai and Oahu, with a return to mostly dry weather thereafter. Except for an increase in trade wind speeds around the middle of the week, a nearby surface ridge will keep winds on the lighter side. After another 24 hours of light and variable winds and essentially zero rainfall, a relatively weak high building NW of the area will push a weak frontal boundary over the islands. This front will bring an increase in low-level moisture that will likely fuel some light showers. The high and associated nearby ridge will support light N to NE winds as the front gradually dissipates through Tuesday, with land and sea breezes in sheltered areas on land. High clouds streaming over the area from the W should shift S, then diminish over the next 24 to 48 hours. Strengthening ENE trade winds may briefly reach moderate levels around mid-week when the high moves to a position NE of the islands. Although confidence is low, trade winds may diminish again by the end of the week as a low passes N of the islands. Limited (windward) to no (leeward) rainfall is expected after the front dissipates. && .AVIATION... Light winds with sea/land breezes are expected through Sunday. Some isolated MVFR cigs and light showers will remain possible over windward Big Island through early this evening. A weak front may bring some MVFR cigs/vsbys to Kauai Sunday afternoon. No AIRMETs are currently in effect. AIRMET Tango will likely be required for moderate upper level turbulence around 30 kft tonight. && .MARINE... A weak front will approach from the northwest tonight, then move into the far western waters Sunday afternoon. The front will then shift slowly southeast down the island chain Sunday night and Monday before dissipating around Maui or the Big Island by Tuesday. Winds will remain light and variable during this time with land and sea breezes developing near the island coastlines. A weak area of high pressure will build in north of the islands around the middle of next week, bringing a return of light to moderate trade winds. A fresh pulse of long-period NNE swell will result in surf peaking below High Surf Advisory heights through tonight, then gradually diminish over the next several days. A new, medium-period NW swell will build tonight and Sunday, with peak surf heights near High Surf Advisory levels along most north and west facing shores, then diminish Monday. Moderate-sized northwest swell will persist for most of the upcoming week. A large long-period NW swell is expected Friday and Saturday, with peak surf heights approaching High Surf Warning levels. No other significant swells are expected. && .FIRE WEATHER... KBDI values remain elevated across leeward areas, and no significant leeward rainfall is anticipated for at least the next several days. Relative humidity values may approach the critical 45% threshold during the late morning and afternoon hours as a relatively dry air mass remains in place. However, light winds will prevent critical fire weather conditions from developing. && .HFO WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION/FIRE WEATHER...Birchard AVIATION...Jelsema MARINE...Jelsema/Birchard