Hawaii Extended Forecast Discussion NWS Weather Prediction Center College Park MD 826 AM EDT Sun Sep 24 2017 Valid 00Z Mon Sep 25 2017 - 00Z Mon Oct 02 2017 A closed low that has been rather stagnant just northeast of Hawaii will finally begin to weaken and lift northeastward early this week, ahead of a large scale upper trough progressing eastward through the north Pacific. At the surface, the influence from a strong and expansive dome of high pressure in the northeast Pacific will continue to diminish while the large scale trough approaches from the west Monday and Tuesday, but then surface ridging could potentially rebuild over the northeast Pacific late this week and into early next weekend. Model guidance is in good agreement with the large scale pattern surrounding Hawaii this week. However, a considerable amount of spread and uncertainty develop by next weekend as an amplifying upper trough approaches from the northwest and possibly closes off an upper low northwest of the Islands. Gerhardt