438
FXHW60 PHFO 300650
AFDHFO

Area Forecast Discussion
National Weather Service Honolulu HI
850 PM HST Sat Jun 29 2024

.SYNOPSIS...
Gentle to moderate trade winds will prevail with afternoon sea
breezes along terrain sheltered western slopes of each island
through the weekend. Trade winds will strengthen into the
moderate to breezy range as sea breezes diminish from Monday
onward. Clouds and passing showers will favor the windward and
mountain areas, trending higher in the overnight to early morning
hours. More stable conditions are forecast from Monday onward
with brief passing showers mainly forming over windward and
mountain areas.

&&

.DISCUSSION...
A subtropical high pressure ridge north of the Hawaiian Islands
will keep trade winds in the forecast through next week. An upper
level low roughly 200 miles north of Oahu will continue to drift
west on Sunday, and then weaken as it moves northward on Monday
away from the region. A weak low level trough under this upper low
will keep trade winds in the gentle to moderate range for one more
day. Upper level forcing from this passing low will enhance shower
activity over the island chain, mainly over windward and mountain
areas in the overnight to early morning hours. Sea breezes will
also develop each day over terrain sheltered areas west of island
mountains. Large scale trades and local scale sea breeze winds
will converge, producing afternoon clouds and showers over these
terrain sheltered locations.

By Monday, the ridge will build into the islands as the upper low
weakens and drifts northward away from the region. Trade winds
will strengthen into the moderate to breezy range through much of
next week. Stronger subsidence under this ridge will stabilize
the atmosphere by lowering the trade wind thermal inversion
heights and reducing cloud heights. Expect mostly brief passing
showers from Monday onward as more stable conditions return to the
Hawaii Region.

&&

.AVIATION...
High pressure north of the islands will maintain moderate trades
through the weekend as an upper-level low continues to drift west.
Leeward sea breezes will continue through this evening. SHRA and
low cigs will return to windward and mauka areas tonight. VFR
should prevail, with brief periods of MVFR under heavier SHRA.

No AIRMETs are currently in effect. However, AIRMET Sierra may
become necessary over portions of the state as SHRA coverage
increases.

&&

.MARINE...
High pressure north of the state will maintain moderate to fresh
trade winds through the remainder of this weekend. By early next
week, trades are expected to strengthen back to fresh and strong
levels, and a Small Craft Advisory will likely be required for the
typically windy waters around Maui and the Big Island.

No significant south swells are expected. However, a series of
small south-southwest and southeast swells will keep south facing
shores from going flat this upcoming week.

Typical mostly flat summertime conditions will continue along
north facing shores through next week.

East shore surf will remain below normal on Sunday, then trend up
and closer to seasonal levels by early next week as the trades
strengthen over and upstream of the islands.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

DISCUSSION...Bohlin
AVIATION...SMW
MARINE...JT