FXHW60 PHFO 091301

AFDHFO



Area Forecast Discussion

National Weather Service Honolulu HI

301 AM HST Fri May 9 2025



.SYNOPSIS...

High pressure north of the islands will keep breezy trade winds in

place through the forecast period. Clouds and showers will favor

windward and mauka areas, particularly at night and during the

early morning hours. A few showers will occasionally reach 

leeward communities due to the strength of the trades, and some 

leeward shower development is expected each afternoon on the Big 

Island.



&&



.DISCUSSION...

Currently at the surface, a 1028 mb high is centered around 1050

miles north-northwest of Honolulu, and is driving moderate to

breezy trade winds across the island chain early this morning.

CIRA ProxyVis imagery shows partly cloudy conditions across much

of the state, with a bit more cloud cover moving into windward

slopes and coasts as well as lingering over portions of leeward 

Big Island. Radar imagery shows isolated to scattered showers

moving into windward slopes and coasts, a few showers spilling

leeward at times over the smaller islands, and some showers 

hugging the leeward Big Island coast. Main short term focus 

revolves around rain chances and trade winds trends.



High pressure north-northwest of the state will shift eastward and

then northeastward through early next week, maintaining breezy 

trade winds across the island chain. The trades may ease slightly

during the middle to latter part of next week as a front passes by

to the north of the state. Fairly typical trade wind weather will

prevail through the forecast period, with showers favoring

windward and mauka areas, particularly at night and during the

early morning hours. A few showers will occasionally reach leeward

communities due to the strength of the trades, and some leeward 

shower development is expected each afternoon on the Big Island.



&&



.AVIATION...

High pressure to the north along with a stable atmosphere will 

allow a breezy trade wind pattern to continue through the next 

several days. Showers will primarily focus over windward and 

mountain areas especially during the overnight and early morning

hours. Periods of enhanced shower activity could lead to 

temporary MVFR conditions at times, however VFR conditions will 

likely prevail.



AIRMET Tango remains in effect for moderate low-level turbulence 

over and immediately SW through NW of all island mountains due to 

the locally breezy trade winds. This AIRMET will likely continue 

for the next few days. AIRMET Sierra for mountain obscuration 

is currently in effect for windward Kauai where a band of 

moisture is lingering over the island generating some MVFR 

conditions.



&&



.MARINE...

Fresh to strong easterly trades will persist through early next

week as a surface ridge remains anchored north of the islands. A 

Small Craft Advisory will persist each day for the typical windier

waters and channels around Maui County, the Big Island, and Kauai.

The advisory may need to be expanded to Maui County windward

waters and the Kaiwi Channel in later packages over the weekend. 



Surf along south-facing shores will trend up above average this 

weekend as a long-period south-southwest swell arrives. 

Forerunners will begin filling in later today, with the surf 

peaking late Saturday through Sunday. This swell peaked above 

guidance at the American Samoan PacIOOS buoy Tuesday night into 

Wednesday, which will translate to a peak locally late Saturday 

into Sunday, likely driving surf to the advisory level. A gradual

downward trend will follow early next week. 



Surf along east-facing shores will remain rough and choppy, with 

heights hovering around average each day.



Surf along exposed north-facing shores will remain small through 

the weekend, with mainly background short-period north-northeast 

energy continuing. A long-period northwest swell arriving late 

Sunday will lead to the surf picking back up to near average 

levels as it peaks Monday. Expect this trend to remain steady 

Tuesday through midweek as another medium-period pulse out of the 

same direction arrives Tuesday night. Expect a downward trend 

through the second half of next week. 



&&



.HFO WATCHES/WARNINGS/ADVISORIES...

Small Craft Advisory until 6 PM HST Saturday for Kauai Northwest 

Waters-Kauai Leeward Waters-Maalaea Bay-Pailolo Channel-

Alenuihaha Channel-Big Island Leeward Waters-Big Island 

Southeast Waters.



&&



$$



DISCUSSION...Jelsema

AVIATION...Almanza

MARINE...Gibbs