National Weather Service Weather Forecast Office

• Home
• Site Map
• News
• Organization
• Search for: NWS All NOAA 

000
FXHW60 PHFO 151611 AAA
AFDHFO

Area Forecast Discussion...UPDATED
National Weather Service Honolulu HI
611 AM HST Mon Apr 15 2024

.SYNOPSIS...
The wet pattern will continue over the eastern end of the state
today as a cold front around Maui County continues eastward.
Meanwhile, light to moderate west-northwest winds with drier air
filling in from west to east will continue in the wake of the
front as high pressure builds north of the state. Expect a more
typical trade wind pattern to return with showers favoring
windward and mauka locations Wednesday through the second half of
the week.

&&

.DISCUSSION...
Updated to correct Watch/Warning/Advisory section.

The short-term guidance remains in good agreement and depicts the
wet pattern persisting today over the eastern end of the state
due to an upper trough to the north and its attendant surface
front slowly advancing down the island chain. Radar imagery
showed the back edge of the moderate showers with decent rainfall
rates along/ahead of the front around Maui early this morning
beginning to weaken. The latest rainfall summary depicted 24-Hr
rainfall totals (through 2 AM HST) ranging from 3 to 5 inches on
Kauai to 1 to 2 inches over Oahu and Maui County. In addition to
the wet conditions, expect a wintry mix over the Big Island
summits this morning with warning level westerly winds. Elsewhere,
light to moderate west-northwest winds and drier conditions have
begun to fill in from west to east. Dewpoints are forecasted to
dip into the upper 50s to low 60s this afternoon, which will limit
rainfall chances. The drying trend will continue over the eastern
end of the state on Tuesday as high pressure builds to the north
and the fronts slips east of the area. A return of a more typical
trade wind pattern with clouds/showers favoring windward areas is
anticipated Wednesday through the second half of the week.

&&

.AVIATION...
A quick-moving cold front will exit Hawaii to the northeast today.
Clearing has already begun on Kauai. Frequent rain showers
possibly mixed with isolated thunderstorms will persist across the
central Islands this morning then taper off from the west in the
afternoon. The front is weakening as it presses eastward, so the
heaviest showers are not expected to reach the Big Island.

Meanwhile, east-southeast flow in advance of the front will carry
repeated bands of light showers towards the Big Island with the
greatest impact being felt along the windward coast south of
Laupahoehoe tonight.

AIRMET Sierra for mountain obscuration is currently in effect for
Maui and Molokai. Conditions are expected to improve in the
early afternoon.

Moderate upper level turbulence could redevelop across the state
later today as the upper level trough to the northwest of Hawaii digs
southward.

Occasional light rime icing is expected in layered clouds above 15
kft. Conditions are expected to persist into the evening hours.

&&

.MARINE...
A front over Maui County will continue to push slowly eastward
today and tonight, then stall out and slowly dissipate near the
Big Island Tuesday and Wednesday. Light to moderate west to
northwest winds will fill in behind the front today, with winds
becoming rather light for Tuesday. Moderate north to northeast
winds will fill in by late Wednesday, with fresh to strong trades
expected Thursday and Friday as high pressure builds eastward well
to the north of the state. The trades appear to ease a bit over
the weekend as the high to the north weakens.

A Small Craft Advisory remains posted for the Alenuihaha Channel
and leeward Big Island waters today due to funneling effects
between Maui and the Big island. A SCA has also been issued for 10
foot seas around Kauai today.

Surf along north and west facing shores will trend up today as a
northwest swell builds. Surf may flirt with low end advisory
levels along north facing shores of the smaller islands late today
and tonight, but should hold just below the advisory threshold of
15 feet. Surf along east facing shores will remain very small
through the week. Small, medium to long period south swells will
keep some small surf rolling into south facing shores through the
week.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
Wind Advisory until 6 AM HST Tuesday for Haleakala Summit.

High Wind Warning until 6 AM HST Tuesday for Big Island Summits.

Winter Weather Advisory until 11 AM HST this morning for Big
Island Summits.

Small Craft Advisory until 6 PM HST this evening for Kauai
Northwest Waters-Kauai Windward Waters-Kauai Leeward Waters-
Alenuihaha Channel-Big Island Leeward Waters.

&&

$$

DISCUSSION...Gibbs
AVIATION...Bedal
MARINE...Jelsema