http://www.prh.noaa.gov/hnl/pages/AFD.php Area Forecast Discussion for Hawaii en-us W-HFO.Webmaster@noaa.gov (Honolulu Webmaster) W-HFO.Webmaster@noaa.gov (Honolulu Webmaster) 13 Feb 2012 20:11:00 GMT http://weather.gov/images/xml_logo.gif http://www.prh.noaa.gov/hnl/pages/AFD.php http://www.prh.noaa.gov/hnl/pages/AFD.php Moderate trade winds will temporarily weaken to gentle east- southeast flow beginning tonight, and back to moderate on Thursday. Winds will then strengthen to fresh to locally strong by Friday backing to easterly. An upper level trough settling over the islands will bring a wetter trade wind pattern to the islands for this weekend. 13 Feb 2012 20:11:00 GMT http://www.prh.noaa.gov/hnl/pages/AFD.php#Synopsis http://www.prh.noaa.gov/hnl/pages/AFD.php An upper level ridge will remain stagnated over the islands through Thursday, keeping conditions stable and precipitation light through the majority of this work week. Radar shows only isolated showers and scattered windward and mauka clouds across the Hawaiian islands this morning, with not many clouds upstream. This should make for a mostly sunny day across leeward spots and partly cloudy for windward areas. Moderate trade winds dominate over the Hawaiian islands at the surface driven by a high centered around 1200 miles northeast of Oahu. A ridge extends west-southwestward from the high, passing 200 miles north of Kauai. A cold front 950 miles northwest of Kauai will move eastward, bringing the ridge closer to the islands and shifting winds out of the east-southeast beginning tonight and weakening our winds slightly. The east-southeast flow should encompass the typical windward sides of the island and adjacent waters. Leeward and interior areas will be a bit more blocked from the weak flow and will likely experience some localized onshore winds on Tuesday. The air mass is slated to remain stable that will minimize of prevent any convective clouds from forming. Medium-range models show that the front will stall around 300 miles northwest of Kauai Wednesday and Wednesday night and dissipate. Winds will boost slightly Wednesday but remain to the east- southeast. A ridge then moves north allowing moderate trades to return Thursday. The high will settle far to the northeast of Hawaii and strengthen, and will back trades easterly while bringing them up to fresh to locally strong. An upper level low will dig on top of the Hawaiian islands Friday night and persist through the duration of next weekend, which will provide enhancement the trade wind driven showers moving beneath. Look for an increase in both windward and leeward showers Friday night through Sunday. In tandem with the breezy trades, an upper trough is slated to settle down over the Big Island end of the state over the upcoming weekend, thus raising the frequency of the trade wind showers. We currently have this wetter trade pattern commencing Thursday night but it could be delayed to Friday night. 13 Feb 2012 20:11:00 GMT http://www.prh.noaa.gov/hnl/pages/AFD.php#Discussion http://www.prh.noaa.gov/hnl/pages/AFD.php Airmet tango is in effect for leeward mechanical turbulence expected to last through today. 13 Feb 2012 20:11:00 GMT http://www.prh.noaa.gov/hnl/pages/AFD.php#Aviation http://www.prh.noaa.gov/hnl/pages/AFD.php The current northwest swell is at 11 feet, and 15 second period at buoy 51101 and rising. At the Waimea buoy it is at 7 feet, 15 seconds, near advisory level surf. Wavewatch iii and buoy 51101 would indicate surf pulsing up this afternoon and back to current levels Tuesday morning. Therefore, the high surf advisory will run through then, with enough of a lull to warrant expiring it tomrrow morning. The next northwest swell will arrive Wednesday night, this one a little bit larger and longer lasting. High surf levels will likely continue from then through Friday. The small craft advisory /sca/ continues as well for all Hawaiian waters except Maalaea Bay Maui. The SCA is due mainly to the current northwest swell which will continue until Tuesday morning. As winds gradually weaken the next 24 hours, some leeward water zones in the SCA may have to drop out Tuesday due to combined seas not reaching the 10 foot criteria. The lowering of the northwest swell should push almost all areas out of the SCA by Tuesday night. 13 Feb 2012 20:11:00 GMT http://www.prh.noaa.gov/hnl/pages/AFD.php#Marine http://www.prh.noaa.gov/hnl/pages/AFD.php High surf advisory until 6 am HST Tuesday for north and west shores of Niihau Kauai Oahu and north shores of Molokai and Maui. Small craft advisory until 6 am HST Tuesday for all Hawaiian waters except Maalaea Bay. 13 Feb 2012 20:11:00 GMT http://www.prh.noaa.gov/hnl/pages/AFD.php#HFO http://www.prh.noaa.gov/hnl/pages/AFD.php FOSTER 13 Feb 2012 20:11:00 GMT http://www.prh.noaa.gov/hnl/pages/AFD.php#footer