008
FXHW60 PHFO 130115
AFDHFO

Area Forecast Discussion
National Weather Service Honolulu HI
315 PM HST Sat Jul 12 2025

.SYNOPSIS...
High pressure well northeast of the islands will maintain
moderate to locally breezy trade winds through much of the week.
Expect passing clouds and showers to favor windward and mauka
areas, with a slight uptick in shower activity Monday and
Tuesday.

&&

.DISCUSSION...
Moderate to locally breezy trade winds brought a shallow band of
moisture over the islands today. An upper-level low drifting
several hundred miles north of the state produced some enhancement
of showers within the moisture band near Kauai, where many
windward sites received over a half of an inch of rainfall today.
Precipitation was more subdued elsewhere, generally less than a
quarter of an inch. Trade winds will push the band westward
tonight and allow drier air to spread to at least Oahu, while
higher chances of rainfall linger on windward Kauai.

Trade winds will remain in the moderate to locally breezy range on
Sunday as high pressure holds far northeast of the state, and
somewhat dry conditions will prevail as precipitable water values
fall below seasonal normal. Expect modest showers to be confined
to windward areas, and with the exception of a few afternoon
showers on the Kona slopes of the Big Island, leeward areas will
be rather dry.

Another area of enhanced moisture will pass over the islands
Monday afternoon into Tuesday. The upper-level low currently near
the state will retreat northward, and a building mid-level ridge
will bring stable conditions. Trade winds will be slightly weaker
and more easterly than usual, which could keep the bulk of the
moisture just north of the islands. Regardless, expect an
increase in showers on windward Big Island midday Monday,
spreading the central islands Monday night, then pushing westward
to Kauai and Oahu on Tuesday.

Tuesday evening through the rest of the coming week, typical
summertime trade wind weather is expected to largely confine
rainfall to windward areas. The northeast Pacific high may drift
closer to the state, leading to a slight uptick in trade winds.

&&

.AVIATION...
Moderate trades will persist through the weekend. Clouds and
showers will generally favor windward and mountain areas across
all islands and may result in MVFR conditions at times. Low clouds
and showers will likely persist for windward areas of most islands
through the afternoon and evening as a band of moisture moves
through the island chain from the east. Otherwise, VFR conditions
will generally prevail.

AIRMET Sierra is in effect for mountain obscuration for the
windward areas of the Big Island from Upolu Point around Cape
Kumukahi to Apua Point due to a line of showery low clouds moving
through. Conditions may improve over Big Island by this evening.
Additional islands may need to be added to the AIRMET later.

&&

.MARINE...
High pressure far northeast of the Hawaiian waters will help
drive moderate to locally fresh trades across the region through
Monday. However, winds may briefly strengthen back to locally
strong speeds tomorrow between the passage of a weak surface
trough across the island chain this afternoon and another one on
Monday. Then as this second weak trough exits the area and the
high to the far northeast gradually strengthens early next week,
trade winds will increase back to moderate to locally strong
levels.

Surf along south facing shores will remain small through the
weekend. A small, long period south swell will arrive Sunday
night into Monday morning and peak late Monday into Tuesday. Then
a mix of this fading south swell and a reinforcing small south-
southeast swell should provide near or slightly below summer
average surf through midweek.

Wind wave driven surf heights along east facing shores will
remain on the small and choppy side through Tuesday, then
increase slightly as trade wind speeds pickup by Wednesday. A very
small northwest swell may pass through early next week, providing
tiny surf along north facing shores on Monday and Tuesday before
becoming nearly flat through the remain forecast period.

&&

.FIRE WEATHER...
Trade winds will remain in the moderate to locally breezy range
for the next several days. While the atmosphere will be rather
dry on Sunday through early Monday, expect typical summertime fire
weather conditions. Higher humidity is favored late Monday into
Tuesday, followed by a return to drier and typical summertime
conditions late Tuesday and Wednesday.

&&

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

&&

$$

DISCUSSION...Wroe
AVIATION...TS
MARINE...Farris/Kino
FIRE WEATHER...Wroe