High Surf in Hawaii, January 9 to 12, 2022

Area Forecast Discussion
National Weather Service Honolulu HI
829 PM HST Sat Jan 8 2022

.SYNOPSIS...
Prevailing light winds, and mostly dry weather will continue into
Monday. A weak front will move down the island chain Monday night
and Tuesday, bringing a brief increase in winds and showers and
ushering in cooler air. Light and variable winds will produce a
land and sea breeze pattern Wednesday through Friday.

&&

.DISCUSSION...
No changes to the forecast this evening. Satellite this evening shows
the cloud band associated with the dissipated front continuing to
fall apart, leaving few clouds across the state. A ridge north of
the islands, and edging southward, will maintain light and
variable winds through Sunday. Expect land and seas breezes to set
up, with skies clearing overnight. The front may have left enough
moisture for a few showers, mainly over Oahu, Sunday afternoon.
Another pocket of low level moisture to the east and southeast may
edge over the Big Island Sunday afternoon helping to produce some
afternoon clouds and showers. Dewpoints are in the low 60s, and
expected to linger there through the remainder of the weekend.
With the light winds tonight, expect overnight low temperatures to
run a couple degrees below normal.

The next front looks to approach the state Monday, and move slowly
across Kauai and Oahu, before falling apart the Big Island
Tuesday. This front looks to have a bit more moisture associated
with it, so expect slightly higher rainfall totals with it,
particularly over the north slopes of Kauai. Ahead of the front
southwest winds will increase to moderate levels on Monday. Both
the ECMWF and GFS suggest some pre-frontal convergence over the
central islands Monday which would increase shower activity there
ahead of the front. Behind the front, drier dewpoints, in the mid
to upper 50s, are expected to spread across the northern end of
the state which will leading to a cool feel.

Behind the front, another ridge is expected to move back over the
state bring another period of light and variable winds. Expect
more land and sea breezes during the second half of the week. A
persistent, zonal west Pacific jet stream could send a disturbance
aloft over the state which could trigger an increase in spotty
showers on Wednesday or Thursday. Otherwise, little significant
rainfall is expected.

The GFS and ECMWF are showing another front stalling just north of
the state next Saturday, favoring continued light winds.

&&

.AVIATION...
Surface ridging over the state will keep winds light and variable
through Sunday. Land breezes will clear skies over the interior
of the islands overnight. Sea breezes will develop again Sunday
afternoon and increase interior clouds, though any showers should
remain light and isolated across the smaller islands. By late
Sunday, an area of moisture that is currently southeast of the
state will move northwestward into the Big Island, increasing
clouds and showers along its east and south facing shores.
Otherwise, VFR flight conditions are expected to prevail
throughout the forecast period.

There are currently no AIRMETs in effect and none are anticipated
through Sunday afternoon.

&&

.MARINE...
Several strong low pressure systems with storm to hurricane force
winds will produce three large northwest swells, from the 300-320
direction, over the next seven day time period. Expect an extended
period of surf heights above High Surf Advisory (HSA) thresholds
affecting exposed north and west facing shores of all Hawaiian
Islands. The peak energy associated with each of these northwest
swells will be strong enough produce surf heights above High Surf
Warning (HSW) levels for the same areas.

The first in this series of northwest swells will continue to
fill in overnight, peaking later tonight and early Sunday, then
slowly lowering from Sunday afternoon through Monday. A HSW
remains in effect until Sunday evening for exposed north and west
facing shores.

A second and slightly larger northwest swell will arrive late
Monday, peaking late Monday night into early Tuesday, and then
slowly lowering from late Tuesday through Wednesday. A third and
equally large northwest swell will fill in Wednesday night,
peaking on Thursday, and then slowly lowering from Thursday night
to Friday. Both of these northwest swells are forecast to produce
two additional periods of warning level surf for all exposed
north and west facing shores.

Winds will remain below Small Craft Advisory (SCA) levels throughout
the forecast period. However, seas will reach or exceed SCA levels
across exposed waters as the above mentioned northwest swells move
across the area. A SCA remains in effect for all Hawaiian Waters,
except Maalaea Bay, through Monday morning due to elevated seas.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
High Surf Warning until 6 PM HST Sunday for north and west facing
shores of Niihau, Kauai, Oahu, and Molokai, for north facing
shores of Maui, and for west facing shores of the Big Island.

Small Craft Advisory until 6 AM HST Monday for all Hawaiian
waters except Maalaea Bay-

&&

DISCUSSION...M Ballard
AVIATION...Thomas
MARINE...Bohlin