Area Forecast Discussion   Issued: 03/15/2026 12:19:00 AM UTC

                        
309
FXHW60 PHFO 141419
AFDHFO

Area Forecast Discussion
National Weather Service Honolulu HI
419 AM HST Sat Mar 14 2026

.SYNOPSIS...
A powerful kona storm will remain anchored northwest of the state
producing periods of hazardous weather impacts across the
Hawaiian Islands through the weekend. Expect a combination of
threats ranging from significant flash flooding, damaging winds,
strong to severe thunderstorms, and snow and ice over the highest
Big Island summits. Strong southwesterly winds will hold today
produce damaging wind gusts. The highest threats for damaging
winds remain along north and east slopes of island mountains.
Unsettled wet weather continues with decreasing southwesterly
wind trends from Sunday into next week. This kona storm begins to
lift northeastward from Sunday to Monday, heavy rain and strong
winds will decrease as severe weather conditions start to ease
across the Hawaii region. However, periods of unsettled wet
weather in a light and variable low level wind pattern will
continue across the state into next weekend.

&&

.DISCUSSION...
Looking into this mornings satellite water vapor imagery, we
continue to see a strong kona storm locked into position northwest
of the Hawaiian Islands. Several higher topped cloud bands
continue to develop and train over the islands in Maui County and
over the Big Island. This satellite picture matches well with
latest local radar imagery, indicating the highest rainfall
amounts are currently falling across the eastern half of the state
at a rate of roughly 1 to 2 inches per hour.

The latest short term forecast guidance shows two negatively
tilted upper troughs passing over the islands today. Upper level
divergence ahead of each of these troughs will trigger pulses of
heavier smaller scale (mesoscale) shower bands potentially training
over the islands. These pulses of shower activity will affect
each island differently, heavy rainfall will pulse down with
decreasing showers after the upper trough passes, and then pulse
back up as the next trough moves into the region. The biggest
challenge today will be forecasting the intensity and track of
these smaller scale heavy rain shower bands, which can
significantly alter observed precipitation amounts over any
location on an hour by hour basis. Overall we remain in a very
unstable weather pattern and additional heavy rain bands will
develop over the islands today.

The Flood Watch remains in effect to cover the threats from
additional heavy shower bands with the ground already saturated
from the large amount of rain that has recently fallen across the
state. Strong southwesterly wind gusts will also continue today
favoring north and east slopes of island terrain and a High Wind
Warning remains in effect. A Winter Storm Warning for snow also
continues for the Big Island summits above 12,000 feet elevation.

From Sunday to Monday, the kona storm begins to rapidly weaken
and lift northeastward. Strong winds across the state will
significantly decrease in the lower elevation areas, and heavy
shower activity will diminish in coverage across the region.
However, periods of unsettled wet weather in a light and variable
low level wind pattern will continue through much of next week.

The extended forecast for next week has evolved over the past 24
hours. A high pressure system is no longer building in north of
the region, rather an upper level troughing pattern will continue
to dominate Hawaiian Island weather conditions through the end of
the week. This means variable light winds each day with periods
of showers and possible thunderstorms lasting into next weekend.

&&

.AVIATION...
Widespread showers, some heavy, along with isolated thunderstorms,
will continue today. The majority of the showers are forecast to
focus on the eastern islands. Expect widespread MVFR to IFR with
local LIFR. Winds will remain strong and primarily out of the
south to southwest. Widespread gusts up to and over 35 kt are
forecast.

AIRMET Sierra remains in effect all islands due to mountain
obscuration, and Oahu, Molokai, Maui, and Lanai for IFR. This is
expected to remain in effect through tonight.

AIRMET Tango remains in effect for moderate upper-level turbulence
between 130 and FL380. and for low-level turbulence due to strong
surface winds. Both of these are expected to remain in effect
through Saturday.

AIRMET Zulu remains in effect, as high clouds from these showers
present icing concerns between FL120 and FL260. This is also
expected to continue through Saturday.

&&

.MARINE...
Gale-force winds in the waters near Kauai will continue to
decline and the Gale Warning was cancelled for waters around
Kauai. Seas will remain elevated in this area so a Small Craft
advisory has been issued around Kauai waters. The gales from Oahu
to the Big Island will continue in association with the strong
kona storm impacting the area. Gusty winds, steep and fast seas,
and low visibility in heavy showers will continue across the
entire marine waters through the weekend.

These gale force southerly winds will create large and rough surf
along south facing shores through this afternoon and as such a
High Surf Advisory is in effect for south facing shores until 6 PM.
The winds by early next week will shift westerly and diminish as
the storm gains increasing distance far to the north of the
islands. As the winds diminish the gale warnings will be expired
and due to high seas a Small Craft advisory will be expanded to
include waters around the smaller islands. Seas will gradually
fall as the system moves off to the north.

A small, short to medium period west to west-northwest swell will
bring small to moderate surf to north and west facing shores
through the weekend. A small, medium period north swell will peak
Saturday before gradually declining. The current south swell will
continue to decline today and through the weekend.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
Flood Watch through this afternoon for Kauai County.

Flood Watch through late tonight for Oahu.

Flood Watch through late Sunday night for Maui County and the Big
Island.

High Wind Warning until 6 AM HST Sunday for all Hawaiian Islands.

High Wind Warning until 6 PM HST Sunday for Haleakala Summit-Big
Island Summits.

Winter Storm Warning until 6 AM HST Monday for Big Island
Summits above 12,000 feet elevation.

High Surf Advisory until 6 PM HST this evening for south facing
shores of all Hawaiian Islands.

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

Gale Warning until 6 AM HST Sunday for Oahu Windward Waters-
Kaiwi Channel-Maui County Windward Waters-Maui County Leeward
Waters-Maalaea Bay-Pailolo Channel-Alenuihaha Channel-Big Island
Windward Waters-Big Island Leeward Waters-Big Island Southeast
Waters.

Small Craft Advisory from 6 AM to 6 PM HST Sunday for Oahu
Windward Waters-Kaiwi Channel-Maui County Windward Waters-Maui
County Leeward Waters-Maalaea Bay-Pailolo Channel-Alenuihaha
Channel.

&&

$$

DISCUSSION...Bohlin
AVIATION...Parker
MARINE...Walsh