Hawaii Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
347 AM EDT Mon Apr 17 2023

Valid 00Z Tue Apr 18 2023 - 00Z Tue Apr 25 2023

Guidance remains fairly agreeable and consistent through this week
and the start of the weekend, with some differences still
appearing late in the period.  Initially expect winds to turn more
southerly and strengthen ahead of an approaching front.  This
front, with an associated band of tropical moisture (precipitable
water values reaching 3+ standard deviations above normal), should
progress eastward across the state and bring the heaviest rainfall
to western areas on Tuesday and central locations on Wednesday. 
Some heavy rain may extend into the Big Island by Thursday as the
front reaches the eastern half of the islands, though with totals
or coverage that may be a little lower than over areas farther
west.  Expect the front to weaken by around Friday with the
lingering moisture band returning back to the northwest from
Friday into the weekend as easterly to southeasterly trades likely
develop.  From the weekend into early next week, GFS runs continue
to bring the next upper system much closer to the state versus
most other solutions.  The 00Z GEFS mean has a more open trough
but still leans in the GFS direction for trough progression. 
Continue to favor a compromise that would keep the front and
associated rainfall focus somewhat westward of the GFS/GEFS mean.

Rausch