Hawaii Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
814 AM EDT Wed Aug 08 2018

Valid 00Z Thu Aug 09 2018 - 00Z Thu Aug 16 2018

The Central Pacific Hurricane Center is advising on Hurricane
Hector, whose track should pass south of the state along 16-17N
latitude today.  Effects on the islands will be very sensitive to
exact track.  The Big Island in particular should see a period of
strong and gusty winds along with some locally heavy rainfall,
given the combination of terrain enhancement as well as an axis of
high precipitable water values expected to spread over the state
near and behind Hector into very early Friday.  An upper trough
stuck across the western sector of the Papahanaumokuakea Marine
National Monument should allow high clouds to spread across the
northwestern section of the archipelago through late this week and
could lead to Hector edging more west-northwest with time as it
approaches the weakness aloft.  See CPHC advisories for more on
the expectations with Hector as it approaches the International
Dateline.

Flow around a strong surface high covering much of the eastern
Pacific building in behind Hector will provide generally moderate
to fresh trades into next week.  Expect another period of
relatively light windward showers this weekend into Monday within
the more climatological air mass.  An upper low/trough is forecast
to slowly approach the 50th state mid next week which should
weaken the trades somewhat, but should remain far enough afield to
prevent any major issues.  The guidance agrees on Kristy, or its
remnants, remaining well southeast of Hawai'i mid to late next
week, though some modest increase in moisture/shower and
thunderstorm coverage appears to be in the cards for Tuesday into
next Wednesday between it and the approaching upper trough.  The
guidance has been unusually variable with its handling of Kristy
over the past five days due to its proximity to John, so the
forecast remains far from certain for next week.  Stay tuned.

Roth/Rausch