985
FXHW01 KWNH 060657
PMDHI

Hawaii Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
157 AM EST Sat Dec 6 2025

Valid 00Z Sun 07 Dec 2025 - 00Z Sun 14 Dec 2025

A cold front in association with a deep trough and cutoff low
west of the state should weaken and retrograde as an easterly wave
this weekend. Winds should moderate back to normal easterly
trades this weekend with the usual windward shower paradigm
expected. A compact cut off low will meander east and northeast of
the state as late as Wednesday but is forecast to have minimal,
if any, impact on precipitation amounts across Hawai`i before it
moves east, out of the picture.

Another cold front moves into the western main islands late Wednesday
at the leading edge of a positively tilted trough. While timing
is no longer a factor, the guidance now allows the front to sweep
cleanly through the main Hawaiian Islands by next Saturday. There
is some difference as to where a closed/occluded low sets up
within the trough, with the GFS a bit farther south with its
cyclone which could bring cooler/drier air across the state. A
compromise position for the deep layer low, north of the 00z GFS,
is currently preferred. In any event, moderate to heavy
showers/thunderstorms are expected to accompany the frontal
passage, though expected rainfall doesn`t appear to be excessive
at the present time as the front is forecast to be progressive.

Roth

$$