Hawaii Extended Forecast Discussion NWS Weather Prediction Center College Park MD 656 AM EST Wed Feb 20 2019 Valid 00Z Thu Feb 21 2019 - 00Z Thu Feb 28 2019 A surface boundary is expected to linger just east of the Big Island through the weekend. Moisture pooling in the vicinity of the boundary (PWs of 1.50-1.80 in.) will continue to bring scattered and locally heavy showers to the Big Island through Sunday. Meanwhile, drier air in place across the other islands should keep shower activity to a minimum. By early next week the surface boundary should move east allowing drier air to spread across the Big Island, reducing shower activity. West of the boundary, light north to northeasterly flow at the surface will persist through the weekend. Aloft, Hawaii will remain on the southern periphery of stronger westerly flow across the North Central Pacific into next week. Models show good agreement that a weak cold front should approach the western islands by Sat night/Sun as a shortwave passes well north of Hawaii. The front appears moisture starved so no significant precipitation impacts are expected, but the front may bring a brief period of gusty north-northeast winds to the western islands. By the middle of next week models show a more significant trough amplifying across the North Central Pacific, with modest height falls extending south to Hawaii and a stronger cold front approaching. Model solutions differ on the precise evolution of this feature, but show general agreement on its existence, thus a solution resembling the ECENS or GEFS ensemble means would be the preference at this time by the early to middle portion of next week. Moisture availability also appears very limited with this front, so the main impact will once again be a period of gusty north winds spreading across Hawaii Tue night through Wed. Ryan