Hawaii Extended Forecast Discussion NWS Weather Prediction Center College Park MD 720 AM EST Wed Nov 13 2019 Valid 00Z Thu Nov 14 2019 - 00Z Thu Nov 21 2019 ...Weekend Heavy Rain Threat... Models and ensembles agree in showing a relatively benign weather pattern for Hawaii into Friday in a pattern with weak flow and limited moisture and showers. The pattern amplifies and becomes more active over the weekend into early next week as guidance shows an increasing signal for significant upper trough amplification to the northwest of the state. Lowering heights and increasing instability will accompany the approach of a cold front into the islands along with a lead increase in deep layered tropical moisture influx into the state. Solutions also agree on the potential for moisture from an easterly wave to potentially also be drawn northward into the frontal zone, with precipitable water values rising upwards to 2 inches. This setup should support the potential for an increasingly widespread threat of heavy rainfall this weekend. By Mon/Tue next week, model guidance still shows upper closed low development is possible, which along with surface high pressure rebuilding north of the state causing the resumption of trades could prolong the threat for locally heavy rainfall especially for the southern islands. A composite guidance solution is favored given favorable solution evolution/clustering. Tate/Schichtel