PHFO issues Area Forecast Discussion (AFD) valid 2019-11-28T01:35:00Z 579 FXHW60 PHFO 280135 AFDHFO Area Forecast Discussion National Weather Service Honolulu HI 335 PM HST Wed Nov 27 2019 .SYNOPSIS... A cold front stalling just west of the islands will keep moisture and rainfall chances elevated over Kauai and Oahu through tonight, while southerly winds keep a muggy air mass in place. Somewhat drier east-southeast winds over Maui and the Big Island will spread to all islands Thursday and Friday as the front gradually weakens and moves away. High pressure passing north of the islands this weekend will support cooler weather, with strong and gusty trade winds bringing passing windward showers, although showers may be especially active around Sunday. && .DISCUSSION... Light to moderate ESE winds over Maui county and the Big Island will gradually spread westward over the next 24 hours, as a stalled front just W of Kauai weakens and begins to drift W. While low-level convergence near the front will keep rain chances elevated over the western end of the island chain through tonight, the Flash Flood Watch for Kauai county was cancelled earlier this afternoon as upper- level support for heavy rain development is absent. The ESE winds will be supported by a relatively weak high centered about 850 miles NE of the islands, with this flow delivering a few windward clouds and showers into the weekend. A new high passing far N of the islands over the weekend will bring an increase in ENE trade winds, especially on Sunday, when the trade winds are expected to push a showery low cloud band (remnants of the front) across the island chain from the NE. After the passage of this weak "backdoor" cold front, slightly cooler air is expected to briefly filter in from the NE Sunday, with dew points potentially dipping into the lower 60's. Latest guidance indicates this will be short-lived, as developing low pressure W of the islands weakens the flow and turns it to the ESE once again from late Monday into Wednesday. && .AVIATION... A cold front, stalled just northwest of the state, will continue to provide additional mid-high cloudiness and some shower activity over/around Kauai and Niihau through tonight, before beginning to weaken and retreat back westward through Thursday. East through southeast slopes of the Big Island will continue to see enhanced clouds and showers in the east-southeasterly wind flow through tonight. Brief MVFR conditions with tempo mountain obscurations are possible in showers, but are not expected to be widespread enough for AIRMET Sierra. Elsewhere mostly VFR conditions are forecast through Thursday. && .MARINE... The current northwest swell will lower gradually through Friday. A larger northerly swell is expected to fill in late Saturday and Saturday night, peak Sunday and Sunday night, then lower gradually gradually Monday and Monday night. Short period surf will continue to affect east facing shores through Saturday with larger surf expected Saturday night through Monday due to the north swell wrapping into exposed shorelines. No other significant swells are expected. A Small Craft Advisory will remain posted through tonight for windward waters of Maui and the Big Island as data from the Hilo buoy continues to show seas of around 10 feet. This will likely be lowered by Thursday morning. Trade winds are expected to increase Friday and on through the weekend. This along with the new northerly swell, will likely cause Small Craft Advisory conditions over a vast majority of the coastal waters. High astronomical tides over the next couple of days may allow for some localized coastal flooding during the morning high tide cycle. A Special Weather Statement is posted with more details. && .HFO WATCHES/WARNINGS/ADVISORIES... Small Craft Advisory until 6 AM HST Thursday for Maui County Windward Waters-Big Island Windward Waters. && $$ DISCUSSION...Birchard AVIATION...TS MARINE...Burke