Hawaii Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
830 AM EDT Mon Jul 18 2016

Valid 00Z Tue Jul 19 2016 - 00Z Tue Jul 26 2016

To commence the period, a closed anticyclone centered between
40/50N latitude will retrograde toward the west this week while a
series of decaying tropical systems track westward underneath. The
first feature of interest is what remains of Celia with infrared
satellite imagery and lightning data indicating a brief flare-up
near its center last night. It appears this remnant circulation
should miss north of the island chain although expect an increase
in shower coverage given the uptick in tropospheric moisture
content. By mid-week, models agree on a shortwave ridge settling
over Hawai`i while the next tropical cyclone approaches from the
east. More specifically, what is currently Hurricane Darby should
begin to approach the Big Island by early in the weekend. This
system may still be tropical in nature based on the latest
National Hurricane Center forecast which extends through Friday
night. While uncertain, there seems to be a modest consensus in
lifting the circulation more northward in response to a weakness
in the mid-level ridge. Considerable weakening appears likely at
this point as the compact low begins to dissipate. Regardless of
the eventual evolution, increasing northeasterly flow is likely in
response to Darby by as early as Thursday. This should bring
sustained surface winds up to 25 knots. 
 

Rubin-Oster