Hawaii Extended Forecast Discussion NWS Weather Prediction Center College Park MD 725 AM EST Thu Nov 15 2018 Valid 00Z Fri Nov 16 2018 - 00Z Fri Nov 23 2018 Expect some increase in the trade winds over the next day or two ahead of upper troughing building over the region by this weekend. There is good agreement between models and ensembles that this troughing and the associated cold front will usher in a moist and unstable air mass over the island chain. This will increase precipitable water values and showery activity, with thunderstorms and locally heavy rainfall possible, especially for windward locations. Surface high pressure builds in behind the system north of the state which will dry things out, but gusty trade winds may continue through the middle of next week. Santorelli