963 
FXHW60 PHFO 200117
AFDHFO

Area Forecast Discussion
National Weather Service Honolulu HI
317 PM HST Wed Jan 19 2022

.SYNOPSIS...

Sea breezes will favor interior clouds and isolated showers this 
afternoon through Friday afternoon. Land breezes will bring clearing 
overnight. Showers will increase over windward sections of Oahu and 
Kauai this weekend as a diminishing cold front settles over the 
western end of the state.
&&


.DISCUSSION...

The weak gradient over the area will support a land and sea breeze 
pattern into Friday afternoon. Interior clouds and isolated showers 
can be expected during peak heating though the high degree of 
stability and dry low-level airmass will limit the coverage and 
intensity of any showers. Land breezes will bring clearing 
overnight. Light to moderate trades will return late Friday as a 
weakening cold front settles over the western end of the state 
bringing windward showers to Kauai on Saturday and Oahu Saturday 
night. Given that the islands will remain south of a strong zonal 
pacific jet during this time, little to no change to background 
stability is expected. As a result, showers should be rather benign 
and mainly confined to windward and mauka zones overnight and during 
the morning. Building trades will then usher the remnant frontal 
moisture axis through remaining islands perhaps supporting a slight 
uptick in showers over windward portions of Maui and the Big Island 
on Sunday. Building mid-level ridging immediately downstream of the 
aforementioned Pacific jet will further increase stability early 
next week leading continued dry conditions as locally breezy trades 
take hold by Tuesday.

&&

.AVIATION...

Light winds will allow local land and sea breezes to develop 
through Thursday. Expect overnight land breezes to clear out the
low clouds which developed across interior areas today. Land 
breezes will then give way to sea breezes Thursday afternoon, 
which will increase cloud cover and trigger a few light showers 
over island interiors. Expect brief MVFR conditions in showers, if
any develop. Otherwise, VFR will prevail.

No AIRMETs are in effect, and none are expected through the 
forecast period.


&&

.MARINE...

A current west northwest swell will peak early tonight, then 
lower gradually through Thursday night. A High Surf Advisory is 
currently posted for most north and west facing shores through 
tonight. A larger northwest swell is expected to fill in on 
Friday, peak Friday night, then lower gradually Saturday through 
Sunday. Surf heights are expected to reach or exceed High Surf 
Warning criteria during the peak of this swell. Another, but 
smaller northwest swell is expected to fill in Sunday night, peak 
on Monday, then lower gradually on into Tuesday. Advisory level 
surf is expected during the peak of this swell. A small east 
northeast swell is possible over the weekend, generated by a 
developing gale low E of the state over the next couple of days. 
There will also be a slight increase in short period choppy surf 
for east facing shores over the weekend and on into early next 
week as light to moderate trade winds return. No other significant
swells are expected. 

Winds and seas will remain below Small Craft Advisory (SCA)
criteria through Thursday night. The above mentioned large
northwest swell will cause seas to exceed SCA levels over exposed
waters Friday afternoon through Saturday night. Strengthening 
trade winds early next week may allow winds to reach SCA levels 
over the typically windy waters around Maui County and the Big 
Island. 


&&

.HFO WATCHES/WARNINGS/ADVISORIES...
High Surf Advisory until 6 AM HST Thursday for Niihau-Kauai 
Leeward-Waianae Coast-Oahu North Shore-Maui Windward West-Kona-
Kohala-Kauai North-Molokai Windward-Molokai North-Molokai West-
Maui Central Valley North-Windward Haleakala.


&&

$$


DISCUSSION...JVC
AVIATION...Powell
MARINE...Burke