488
FXHW60 PHFO 250707
AFDHFO

Area Forecast Discussion
National Weather Service Honolulu HI
907 PM HST Thu Sep 24 2026

.SYNOPSIS...
Hurricane Nolo will drift northward toward the Big Island through
Friday night, before making a turn to the west. As the deep
moisture along the northern edge of the system moves northward,
rainfall will increase across the Big Island and Maui, leading to
the potential for significant flash flooding on windward and
southeast Big Island.

&&

.DISCUSSION...
No changes to the forecast with the evening package, but
considering issuing a wind advisory for Kauai and Oahu with the
morning package.

The relatively typical trade wind pattern continues with lower
clouds and showers riding in on the easterly winds. Hurricane Nolo
continues its slow northward movement towards the Big Island, and
plenty of high clouds are reaching Maui County and the Big Island,
with some of the high clouds reaching Oahu. Trades continue to
gust are currently gusting to around 20-25 mph in most locations
with localized gusts approaching 50 mph in some of the more
typical windier areas of Maui County and the Big Island.

Satellite derived precipitable water (PW) shows the deeper
moisture just south of the Big Island, so expecting that to move
overhead in the coming hours. Despite consensus on the position
of Nolo, and subsequent placement of deeper moisture, there
remains significant differences in the QPF between the global
models, particularly over the Kau District of the Big Island. As
mentioned in the previous discussion, the rainfall totals were
trended down some, however the possibility of localized
significant totals remains. Strengthening northeast winds are
expected to drive moderate to heavy showers over windward
portions of the Big Island and Maui as moisture deepens and
spreads northward over the region.

As mentioned above, continuing to evaluate headlines for Kauai and
Oahu. Am leaning towards a Wind Advisory, but will see what the
latest forecast track for Nolo is by morning to make that
decision. A High Wind Watch for Oahu Saturday and Saturday night
remains a possibility. The Hurricane Watch and Tropical Storm
Warning remain in effect for the Big Island and the Tropical Storm
Watch continues for Maui County.

By the middle of next week, troughing will draw Nolo sharply north
or northeastward west of Kauai. The end of next week will then feature
light south to southeast flow as Nolo lifts north of the area and
gradient over the state weakens substantially.

&&

.AVIATION...
Gusty trade winds continue with scattered showers extending from
the Big Island to Oahu this evening. Highest confidence in MVFR
conditions on the Big Island with IFR to LIFR conditions becoming
more likely late Friday morning into the afternoon as more
widespread rain reaches the island. Thunderstorm chances remain
low for the Big Island but will increase slightly heading into
Friday evening as Nolo moves closer to the islands. Winds
strengthen throughout the day on Friday with peak gusts between 30
to 40 knots expected across the islands. Expect winds to stay
largely out of the east to southeast. VFR conditions continue for
the rest of the islands but brief periods of MVFR conditions are
possible if a stronger shower develops.

AIRMET Sierra is in effect for mountain obscuration for windward
areas of Maui and the entire Big Island. This AIRMET will likely
be expanded Friday to include other areas as Hurricane Nolo
continues its approach.

AIRMET Tango remains in effect for moderate turbulence downwind of
island terrain due to breezy trade winds. Expect this to continue
through the forecast period.

TC SIGMET series Oscar covers Hurricane Nolo.

&&

.MARINE...
At 8 PM HST, the center of Hurricane Nolo is located approximately
220 nautical miles south of South Point, Big Island. Nolo is
expected to continue strengthening over the next couple of days
as it tracks slowly north through Friday, then turns west passing
south of the Hawaiian Islands this weekend. Nolo`s maritime
impacts will include increasing winds, waves, and rainfall
probabilities across both the nearshore and offshore waters
primarily south of the Hawaiian Islands through the weekend. A
Tropical Storm Warning and a Hurricane Watch continues for the
nearshore waters surrounding Big Island, including the Alenuihaha
Channel, while a Tropical Storm Watch remains in effect for the
waters of Maui County including the Kaiwi Channel, and a Small
Craft Advisory remains in effect for the remainder of the near
coastal waters and channels surrounding Kauai and Oahu.

For the western islands, the current small south swell will
continue to fade as another small overlapping southwest swell
builds in from Friday into the weekend. Meanwhile, Hurricane Nolo
will likely produce a southerly swell resulting in surf reaching
advisory thresholds for exposed south-facing shores, initially for
Big Island, then potentially expanding westward across the state
this weekend. Additionally, strong trades will likely result in
advisory level surf for the eastern island east-facing shores
tonight into Friday, potentially expanding to remaining islands
later Friday into the weekend as stronger winds continue to expand
westward. A High Surf Advisory is in effect for the east and
southeast-facing shores of Big Island, Maui and Molokai.

A new small, long period, northwest swell will fill in this
weekend keeping surf slightly elevated along north and west-
facing shores into early next week. Finally, dangerously large
wind waves will produce a rough and choppy sea state for much of
the area over the next few days, with the largest waves (which
could exceed 20 feet in some locations) expected around Maui
County and Big Island.


&&

.FIRE WEATHER...
Issued at 854 PM HST Thu Sep 24 2026

Winds will steadily as Hurricane Nolo moves closer. By Friday,
very strong winds are possible on Big Island though heavy rainfall
will likely mitigate fire danger over most areas. From Kauai to
Maui County, rainfall over the last month has led to some
improvement in fuels, but the gusty trade winds will produce
moderate fire weather conditions over drier leeward areas through
the weekend.


&&

.HFO WATCHES/WARNINGS/ADVISORIES...
Flood Watch through Saturday afternoon for Big Island East-Big
Island Interior-Big Island North-Big Island South-Big Island
Southeast-Big Island Summits-Haleakala Summit-Kahoolawe-Kipahulu-
Kohala-Kona-Lanai Leeward-Lanai Mauka-Lanai South-Lanai Windward-
Maui Central Valley North-Maui Central Valley South-Maui Leeward
West-Maui Windward West-Molokai Leeward South-Molokai North-
Molokai Southeast-Molokai West-Molokai Windward-South Haleakala-
South Maui/Upcountry-Windward Haleakala.

Tropical Storm Watch for Haleakala Summit-Kahoolawe-Kipahulu-
Lanai Leeward-Lanai Mauka-Lanai South-Lanai Windward-Maui
Central Valley North-Maui Central Valley South-Maui Leeward West-
Maui Windward West-Molokai Leeward South-Molokai North-Molokai
Southeast-Molokai West-Molokai Windward-South Haleakala-South
Maui/Upcountry-Windward Haleakala.

High Surf Advisory until 6 PM HST Saturday for Big Island East-
Big Island North-Big Island Southeast-Kipahulu-Maui Windward
West-Molokai Southeast-Molokai Windward-South Haleakala-Windward
Haleakala.

Hurricane Watch for Big Island East-Big Island Interior-Big
Island North-Big Island South-Big Island Southeast-Big Island
Summits-Kohala-Kona.

Tropical Storm Warning for Big Island East-Big Island Interior-
Big Island North-Big Island South-Big Island Southeast-Big
Island Summits-Kohala-Kona.

Tropical Storm Watch for Kaiwi Channel-Maalaea Bay-Maui County
Leeward Waters-Maui County Windward Waters-Pailolo Channel.

Hurricane Watch for Alenuihaha Channel-Big Island Leeward Waters-
Big Island Southeast Waters-Big Island Windward Waters.

Tropical Storm Warning for Alenuihaha Channel-Big Island Leeward
Waters-Big Island Southeast Waters-Big Island Windward Waters.

Small Craft Advisory until 6 PM HST Saturday for Kauai Channel-
Kauai Leeward Waters-Kauai Northwest Waters-Kauai Windward
Waters-Oahu Leeward Waters-Oahu Windward Waters.


&&

$$

DISCUSSION...M Ballard
AVIATION...DT
MARINE...Blood
FIRE WEATHER...JVC