Hawaii Extended Forecast Discussion NWS Weather Prediction Center College Park MD 755 AM EDT Sun Sep 03 2017 Valid 00Z Mon Sep 04 2017 - 00Z Mon Sep 11 2017 To the northwest of the islands, a slowly approaching cold front is forecast to only slowly drift southeast towards the islands or even stall into next week. The consensus is the front actually weakens and not actually make it into the islands during the middle portion of the week. Trades are forecast to be lighter than normal. Scattered showers and thunderstorms are forecast each day, driven by sea breezes each afternoon. During the middle and latter portions of next week, the models/ensemble means are in better than average agreement on the low level high building north of Hawaii. Trades should then return to near normal levels during this middle to latter portions of the week. Both the gfs and ecmwf show a tropical wave moving south of the islands in middle of the week. The current rainfall forecasts show the higher amounts remaining south of the islands. The higher available moisture does support the possibility of enhanced coverage of showers near when the wave passes, particularly in the big island. Another tropical wave may approach from the east next weekend. There remains better than average agreement among the 06z gfs and 00z ecmwf 700-500 mb forecasts next week to use a blend of the two to mitigate differences. Petersen