Hawaii Extended Forecast Discussion NWS Weather Prediction Center College Park MD 809 AM EDT Sun Mar 26 2017 Valid 00Z Mon Mar 27 2017 - 00Z Mon Apr 03 2017 The upper level pattern over Hawaii for the upcoming week features large-scale ridging centered along roughly 30 degrees north latitude, with good agreement amongst the operational models and their ensembles that any major systems should remain well north of the state. Expect a mainly typical trade wind pattern, with some weakening in speed early in the week as the upper ridge breaks down and a trough approaches to the north. Precipitation should remain light and confined to mainly windward and mountainous areas during that time. By mid-week, models continue to advertise a surface low intensifying across the northern Pacific and tracking towards Alaska. The implications for Hawaii will be the trailing cold front towards the end of the week, which will bring another break in the subtropical ridge. Models are not indicating anything in terms of significant precipitation with this system, but would expect to see an increase in showery activity across the islands by Thursday and Friday. Santorelli