Area Forecast Discussion
Issued by NWS Honolulu, HI
Issued by NWS Honolulu, HI
490 FXHW60 PHFO 200101 AFDHFO Area Forecast Discussion National Weather Service Honolulu HI 301 PM HST Wed Jun 19 2024 .SYNOPSIS... Persistent high pressure far north of the islands will support locally strong trade winds through the weekend. Brief, passing showers will favor windward areas, especially during nights and mornings, with a few sprinkles occasionally spreading leeward. && .DISCUSSION... Benign trade wind weather continues through the forecast period. The inversion on this afternoon`s soundings is anchored between 5 and 6kft. At the surface, this is translating into stable low clouds that are delivering limited showers to windward and mauka zones. Little change expected during the next 24 hours as highly stable and breezy trades persist. Thereafter, trades get a modest boost as the pressure gradient strengthens over the forecast area with locally strong trade winds then continuing into the weekend. At the same time, upstream moisture embedded within the prevailing trade wind pattern will arrive late Thursday night marking the onset of a somewhat wetter trade wind pattern. An upper low parked over the area will slowly drift westward funneling periodic high clouds into the area for the next several days. && .AVIATION... Breezy to locally windy trade winds will persist through forty- eight hours and beyond. Bands of light showers off the Pacific will be steered twoards east and northeast facing slopes and coasts. Isolated spillover showers are to be expected along leeward slopes, especially in the late night and morning hours. A weak eddy just west of the Big Island may keep the Kona coast covered in clouds overnight. Low ceilings and visibities could redevelop along windward slopes of the Big Island late tonight or Thursday morning. Elsewhere, VFR condtions will prevail except for brief MVFR conditions in passing showers. AIRMET Tango remains in effect for low level turbulence lee of mountains due to the breezy trade winds. && .MARINE... Fresh to strong trade winds will increase Thursday and Friday as surface high pressure to the north-northeast strengthens and settles about 800 nm north of the islands. A Small Craft Advisory remains in effect for most waters around the Big Island and Maui County and will expand to most waters as the trade winds increase. Fresh to near-gale winds will hold through the weekend and likely into early next week. Expect minimal south shore surf into Friday. A mix of a small, long-period south swell and a shorter period southeast swell may push surf close to seasonal average during the weekend. As these swells slowly decline early next week, another small, long-period south-southwest swell is expected to fill in. Surf along east-facing shores will gradually trend up during the weekend. The trade wind swell is currently at 6 to 7 feet at 7 to 8 seconds and will rise slightly to around seasonal average with the increased winds this weekend. Surf along north facing shores will be at seasonally tiny levels through much of the week, with very small pulses of northwest swell possible Thursday and early next week. && .HFO WATCHES/WARNINGS/ADVISORIES... Small Craft Advisory until 6 PM HST Saturday for Kaiwi Channel- Maui County Windward Waters-Maalaea Bay-Pailolo Channel- Alenuihaha Channel-Big Island Leeward Waters-Big Island Southeast Waters. && $$ DISCUSSION...JVC AVIATION...Bedal MARINE...Wroe