Hawaii Extended Forecast Discussion NWS Weather Prediction Center College Park MD 724 AM EST Mon Feb 26 2018 Valid 00Z Tue Feb 27 2018 - 00Z Tue Mar 6 2018 The inverted surface trough and upper level low that was northwest of the state will weaken and lift to the north. A strong surface high will become established between Hawaii and California through Thursday with steady easterly trade winds expected with periods of mainly orographically forced showers, with the axis of greatest QPF centered near 165W over the open waters of the Pacific. The models and ensembles are in decent agreement on the synoptic scale pattern over the Hawaii domain going into the second half of the forecast period for the end of the week and into the weekend. A hint of an omega block flow pattern over the central Pacific is indicated in the guidance for Thursday and Friday, with the main ridge axis situated generally near 150W with upper level troughs to the southwest and southeast of the upper level high. The EC mean remains slightly more amplified with the upper level ridge than the GEFS mean, with both solutions breaking down the ridge by next Sunday. Another weak upper low will likely form near 170W by Friday and into Saturday according to both the GEFS and EC means. This may once again advect deeper moisture northward across the westernmost part of the Islands for the end of the week. By the end of the forecast period, the upper level high becomes established northwest of the Islands. D. Hamrick