Hawaii Extended Forecast Discussion NWS Weather Prediction Center College Park MD 824 AM EDT Wed Apr 11 2018 Valid 00Z Thu Apr 12 2018 - 00Z Thu Apr 19 2018 An upper ridge and 1032mb surface high pressure to the north of Hawai'i will slide eastward and weaken through the end of the week as a lingering moisture plume drifts northwestward across the islands. This will support weakening trades and scattered generally light (but locally moderate) showers over favored upslope/mauka areas. By late Friday an upper low will form just west of the area and move westward underneath another upper ridge axis along 165W. This should guide a surface front toward the northern islands by early this weekend before dissipating and ensembles generally shunt the moisture axis west of the region next week. This should keep showers on the lighter side next week as another surface high (near 1040mb early Sunday) sinks southeastward, increasing trades again. Fracasso