Area Forecast Discussion for Hawaii

Area Forecast Discussion   Issued: 07/18/2026 11:18:00 AM UTC

                        
411
FXHW60 PHFO 180118
AFDHFO

Area Forecast Discussion
National Weather Service Honolulu HI
318 PM HST Fri Jul 17 2026

.SYNOPSIS...
Locally breezy trade winds will remain through the weekend, easing
a bit early next week. Typical trade wind showers will favor
windward and mauka areas.

&&

.DISCUSSION...
This afternoon, radar and satellite imagery shows a typical
summertime trade wind pattern, with a larger amount of windward
showers over the Big Island. Windward and mountain areas of all
islands will see passing showers through tomorrow then a
noticeable decrease is possible by Sunday as drier air moves
through. Next week will see a usual summertime trade shower
pattern, favoring windward and mountain areas as well as the
overnight/early morning hours. The Kona slopes will also have
their daily afternoon cloud and shower buildups.

High pressure will remain far north of the area will maintain
light to locally breezy east- northeast trade winds through
Saturday. By Sunday into early next week the high looks to get
disrupted and move east. This will allow trade winds to weaken a
little bit during the beginning of next week. Long range guidance
then shows the high re- strengthening and allowing trades to
become breezy again during the second half of next week. A ridge
aloft will maintain stable conditions that will keep most showers
light to moderate.

&&

.AVIATION...
AIRMET Sierra is posted for tempo mountain obscurations above 2500
feet this afternoon for the Big Island due to convective cloud
build ups and showers. Expect these clouds to dissipate overnight
with AIRMET Sierra cancelled at that time.

Otherwise, moderate trades will continue through the weekend.
Passing clouds and showers will be focused over the typical
windward and mauka locations. VFR conditions are expected to
prevail, with some windward MVFR conditions in clouds and
showers.

&&

.MARINE...

As high pressure far north of the islands edges slightly south and
east through this weekend and interacts with a couple of lows and
troughs passing to the south and southwest of Hawaii, trades will
remain fresh to locally strong. A Small Craft Advisory (SCA) is
in effect for the windier waters and channels around Maui County
and the Big Island through Saturday afternoon. Winds will begin to
diminish again late this weekend as high pressure to the north
starts to weaken, which should eliminate the need for a SCA Sunday
into early next week.

A small, medium-period west-northwest swell will gradually fade today
into the weekend, causing surf along north-facing shores to drop to
flat/tiny by the weekend. Surf along south facing shores will
remain elevated keeping levels near average through Saturday. A
larger, moderate south swell is expected to build Sunday through
early next week, bringing potentially High Surf Advisory level
conditions Monday and Tuesday. As this swell slowly fades into the
middle of next week, another moderate south swell is expected next
Thursday.

East facing shores will remain choppy through Saturday and will
gradually drop as trade winds ease. Energy from Tropical Storm
Elida may reach the islands during the middle of next week
bringing a slight boost for east facing shores.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
Small Craft Advisory until 6 PM HST Saturday for Maalaea Bay-
Pailolo Channel-Alenuihaha Channel-Big Island Leeward Waters-Big
Island Southeast Waters.

&&

$$


DISCUSSION...Tsamous
AVIATION...Foster
MARINE...Shigesato