Hawaii Extended Forecast Discussion NWS Weather Prediction Center College Park MD 818 AM EDT Wed Sep 30 2015 Valid 00Z Thu Oct 01 2015 - 00Z Thu Oct 08 2015 ...Widespread heavy rain possible this coming weekend into early next week... Rather typical conditions should prevail over the Hawaiian islands for the balance of the week as a deep upper low dips to near 30N along 150W late Friday. Windward showers and modest trades are expected. Over the weekend and into next week, the models and ensembles still suggest one or multiple tropical moisture surges or organized systems pushing northward from the monsoon trough south of the region. There remains good agreement on a large surge in PW values well above climo values -- nearing 3 inches per many ensemble members. Even if this is overdone, as can be the case, PW values of 2 inches support the risk for heavy rainfall over basically all of the island chain. The ECMWF still lies on the east side of the ensemble spread, but remains a viable solution as the ensembles suggest genesis anywhere between 170W and 150W. Upper trough forming to the NW of the islands early next week should help pull moisture over the region through next Wednesday when the ensembles take the trough axis east of 155W. The GFS and ensembles represent a reasonable solution as of now. Fracasso