Hawaii Extended Forecast Discussion NWS Weather Prediction Center College Park MD 200 AM EST Mon Dec 13 2021 Valid 00Z Tue Dec 14 2021 - 00Z Tue Dec 21 2021 High pressure established to the north of Hawaii has ushered in relatively dry weather conditions with breezy trades and limited windward and mountain showers today under upper ridging. A prefered blend of well clustered models and ensembles indicates that a weakening boundary will sag southward over the state later today into midweek, leading to a period with pooled moisture and instability to fuel an increase in showers/downpours. The upper ridge erodes through mid-later week as uncertain weaknesses settle aloft. Deeper shower fueling moisture may be drawn into the islands by the weekend and into early next week as trades further respond to ample upper troughing set to dig just to the northwest of the islands that has a growing guidance signal. Schichtel