Hawaii Extended Forecast Discussion NWS Weather Prediction Center College Park MD 728 AM EDT Fri Jun 29 2018 Valid 00Z Sat Jun 30 2018 - 00Z Sat Jul 07 2018 An upper level trough remains north of the islands over the weekend into early next week, when it resumes a slow westward motion. In its place a high amplitude north Pacific ridge builds east of the islands and slowly approaches in the middle to latter portions of next week. The low level ridge with embedded closed highs drifts north of the islands late this week before drifting northeast this weekend and back north of the islands early next week. This weekend, the high located to the northeast allows the trades to slacken. As the high moves north of the islands and strengthens next week, moderate to brisk trades resume. The persistence of the large, sprawling high results in a uniform pressure gradient supporting moderate to brisk easterly trades through most of next week. The 06Z GFS/GEFS and 00Z ECMWF/ECMWF ensemble mean showed good agreement on the forecast into next week and a blend of those solutions is recommended. Expect mostly windward showers through the weekend and next week, with higher totals in windward areas with stronger terrain gradients. The ECMWF shows a tropical wave moving east to west across the islands early next week. An enhancement of showers across the islands would occur if this comes to fruition, followed by drying aloft as the high to the north forces the moisture channel south of the islands. Petersen