Hawaii Extended Forecast Discussion NWS Weather Prediction Center College Park MD 812 AM EDT Tue Apr 23 2019 Valid 00Z Wed Apr 24 2019 - 00Z Wed May 01 2019 Upper ridging to the west of the region will slide to the east over Hawai'i late Wednesday into Thursday, favoring generally light windward showers amid a typical trade pattern. By the weekend, an upper low to the south of the Aleutians is forecast to drop southeastward to between 35-40N passing 160W around 12Z Sunday. The 00Z GFS/Canadian and their means were a bit farther south than the 00Z ECMWF and its ensemble mean as the upper low is forecast to push to the southeast to near 36N/153W late next Tuesday (though all models were tightly clustered by the end of the period). The 00Z ECMWF ensemble mean was displaced to the northeast perhaps as a result of some very strong members to the north (over Alaska) with upper ridging. Blend of the GFS/ECMWF would suffice for now given the relatively low spread. Below average precipitable water values are expected to rise this weekend into next week as the front associated with the deep upper low to the north approaches Kauai at the end of the weekend. Easterly trades will veer to southeasterly and southerly next week which will increase the threat for more widespread and potentially locally heavier rainfall. However, the ensembles do not appear to tap deep tropical moisture and/or it may stay to the east of the region as the upper low continues eastward. Fracasso