Hawaii Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
759 AM EDT Sat May 18 2019

Valid 00Z Sun May 19 2019 - 00Z Sun May 26 2019

Models/ensembles show good consensus that upper-level ridging
should generally remain dominant across Hawaii through the next
week with a surface high north of the state keeping a trade wind
pattern in place into early next week. A weakness in the ridge is
forecast to traverse the state late Sun into Mon, but with limited
moisture only a modest increase in windward shower activity is
expected with this feature. By mid to late next week, upper
ridging is expected to expand northward between Hawaii and Alaska
as part of a broad mid-latitude flow amplification forecast around
much of the northern hemisphere. With an upper trough amplifying
well northwest of Hawaii and a surface front expected to stall
several hundred miles west of Hawaii, this setup should begin to
increase moisture across the state, with further increase in
low-level moisture aided by veering of low-level winds to
east-southeasterly through late next week.

Ryan