Hawaii Extended Forecast Discussion NWS Weather Prediction Center College Park MD 714 AM EST Mon Jan 29 2018 Valid 00Z Tue Jan 30 2018 - 00Z Tue Feb 06 2018 Expect a period of relatively dry conditions early this week with the departure of the shortwave trough initially over the Big Island. Any light showers that develop should vary in focus Monday-Tuesday as low level winds transition from light trades to light/variable and by Tuesday southerly/southwesterly with the approach of a cold front. Guidance agrees fairly well that this front will bring the potential for areas of locally moderate-heavy rainfall into the northern and central islands late Tuesday onward. The front will likely dissipate but persistence of mean troughing aloft to the west/northwest should hold the axis of enhanced moisture in place over at least portions of the state through the weekend and possibly into next week. As has been the case in recent days, GFS/GEFS mean runs still show lower heights aloft on the southeast side of the upper trough compared to most other guidance especially from Saturday onward. Into the weekend this has the effect of the GFS-based guidance showing more focused moisture/rainfall over the islands. Then by next Sunday-Monday the GFS pushes a front toward and eventually through the area while ECMWF runs show much slower progression. Similar to yesterday the 00z CMC shows progression of a surface boundary even though its upper trough is not as deep as the GFS. Overall would recommend a compromise solution for moisture/rainfall into the weekend as the general pattern appears favorable for rainfall and multi-day ECMWF trends appear wetter though not with the focus of the GFS. Then the recent tendency for GFS runs to slow down fronts relative their days 6-7 forecasts would recommend leaning somewhat more in the ECMWF/ECMWF mean direction by Sunday-Monday. Rausch