Kahului, Hawaii 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

554
FXHW60 PHFO 050110
AFDHFO

Area Forecast Discussion
National Weather Service Honolulu HI
310 PM HST Thu Dec 4 2025

.SYNOPSIS...
Breezy ESE winds will weaken and back to easterly during the
weekend. Limited clouds and showers will focus windward and mauka
during this time.

&&

.DISCUSSION...
Convergence and moisture pooling along a cold front supports ongoing
convection west of Kauai. This convection will persist through
today, then dissipate this evening into tonight as the supporting
upper trough lifts to the north. This then allows moderate to breezy
ESE winds to usher remaining frontal moisture west of the area
leaving the islands mostly dry, including Kauai. The only sensible
wx effect of the front locally will be increased cirrus gracing
western skies. Given the observed inversion at Lihue this morning
around 4.5kft, expect relatively little to no shower activity.

A batch of moisture embedded within the tropical easterlies is
observed on visible imagery around 150W/18N. Modeling indicates this
moisture advances toward the area within prevailing ESE low/mid
level flow and focuses showers chiefly over favored slopes of the
Big Island and Windward Haleakala on Maui tonight through Friday.
This moisture may supply ESE flow with enough moisture to support a
few showers across both windward and leeward portions of the smaller
islands during this time, but no organized or heavy rainfall is
anticipated.

Another punch of dry mid-level air brings reinforcing stability over
the weekend as the Pacific Jet extends eastward leaving the islands
in a region of large scale subsidence. Dry, moderate trades continue
into next week.

&&

.AVIATION...

Strengthening winds out of the southeast will continue through
Friday as high pressure builds across the area. VFR conditions
prevail with only isolated mountain obscurations this afternoon. A
few clouds and showers may impact windward and southeast Big
Island overnight, but partly cloudy skies will continue across the
rest of the state.

AIRMET Tango for tempo moderate leeward turbulence is expected to
go into effect later tonight as the southeast winds pick up. No
other AIRMETs are in effect or anticipated tonight.


&&

.MARINE...

A trough west of Kauai will gradually weaken and retrograde
westward, away from the islands. Meanwhile, a ridge of surface
high pressure building northeast of the state will allow for
moderate to locally strong east or east southeast winds to
persist through early Saturday. A Small Craft Advisory (SCA)
remains in effect through 6 AM Saturday morning for most of the
marine zones surrounding the Big Island and Maui County for strong
winds, and the north and western zones around Kauai and Oahu have
been added starting at 6 PM this evening for building seas.

A moderate, medium period northwest swell (320 degrees) is
filling in across north and west facing shores of Kauai and Oahu
this afternoon as seen at the Waimea buoy, bringing surf heights
above High Surf Advisory (HSA) criteria. This swell is expected to
peak tonight into early Friday, then ease into the weekend. A HSA
is in effect for north and west facing shores of Oahu and Kauai
this afternoon and will expand across north and west shores of
Molokai and north shores of Maui this evening. This swell will
hold through Friday, then gradually fade and veer to the north
northwest through the remainder of the weekend and into early next
week and bring below average surf for December for north and west
facing shores.

East shore surf will gradually build and become choppy tonight through
Friday as trade winds increase. Expect minimal background energy
for south facing shores through much of the week.

Peak monthly tides combined with water levels that are running
higher than predicted will likely lead to minor flooding along
the shoreline and in low-lying coastal areas. Coastal flooding is
possible around the daily peak tide, which will be during the
early morning hours. This could also magnify effects of the high
surf on coastal areas along north and west facing shores around
the same time frame.


&&

.FIRE WEATHER...
Critical fire weather conditions are not expected this week.
Light winds will give way to mainly moderate east to southeast
winds today, but winds will be below the critical fire weather
threshold. The inversion morning sloped from around 4.5kft at
Lihue to around 7.5kft at Hilo.


&&

.HFO WATCHES/WARNINGS/ADVISORIES...
High Surf Advisory until 6 PM HST Friday for Niihau-Kauai
Leeward-Waianae Coast-Oahu North Shore-Kauai North.

High Surf Advisory until 6 PM HST Friday for Maui Windward West-
Molokai Windward-Molokai North-Molokai West-Maui Central Valley
North-Windward Haleakala.

Small Craft Advisory until 6 AM HST Saturday for Kauai Northwest
Waters-Kauai Windward Waters-Kauai Channel-Oahu Windward Waters-
Kaiwi Channel.

Small Craft Advisory until 6 AM HST Saturday for Maui County
Windward Waters-Pailolo Channel-Alenuihaha Channel-Big Island
Windward Waters-Big Island Leeward Waters-Big Island Southeast
Waters.


&&

$$


DISCUSSION...JVC
AVIATION...Foster
MARINE...Farris
FIRE WEATHER...JVC