Flash Flood Warning 8, NWS Honolulu, HI

817 
WGHW70 PHFO 022045
FFSHFO

Flash Flood Statement
National Weather Service Honolulu HI
1045 AM HST Sun Oct 2 2022

HIC007-022055-
/O.CAN.PHFO.FF.W.0008.000000T0000Z-221002T2100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Kauai HI-
1045 AM HST Sun Oct 2 2022

...FLASH FLOOD WARNING IS CANCELLED FOR THE ISLAND OF KAUAI IN KAUAI 
COUNTY...

The heavy rain has moved offshore and no longer poses a threat. 
Water levels in streams are trending down and Kauai Emergency
Management reports no impacts at this time.

LAT...LON 2222 15933 2216 15930 2215 15928 2205 15932
      2196 15932 2195 15934 2193 15934 2186 15944
      2188 15962 2194 15968 2198 15978 2206 15980
      2216 15974 2224 15958 2222 15952 2225 15949
      2224 15943 2225 15940

$$

AG/LT

Area Forecast Discussion
National Weather Service Honolulu HI
350 AM HST Sun Oct 2 2022

.SYNOPSIS...
A cold front will move in from the north this morning, stall near
Maui tonight and dissipate Tuesday. Widespread rain and building
trade winds are expected to accompany this frontal passage. An
area of tropical moisture will move over the Big Island during the
second half of this week.

&&

.DISCUSSION...
An east to west oriented cold front is moving south over the
island of Kauai early this morning. Infrared satellite shows this
front as a 200 mile wide band of showery low clouds with embedded
thunderstorms along the southern edge. The 12Z Lihue sounding
shows an unstable vertical profile with a precipitable water
value of 1.75 inches. Showers have already picked up over the
windward coastal waters of Kauai and Oahu this morning, and will
move over both islands in the next couple of hours, and then over
Maui County later today.

Trade winds will briefly strengthen today along the front due to
high pressure building behind this boundary, but should begin to
weaken by tonight. While the trades will focus more of the
rainfall across windward areas, both windward and leeward areas of
smaller islands will see widespread showers today. Isolated
thunderstorms are also possible today and tonight across the
smaller islands.

The front will pass Kauai by the end of today, and Oahu tonight
with drier air moving in behind. The front will stall over Maui
or the northern end of the Big Island on Monday and Tuesday and
trades will keep showers moving across this area over the next
couple of days as the front dissipates. The rest of the Big
Island will stay a bit drier than the rest of the state.

An area of tropical moisture will pass to the south during the
second half of the week. The the northern edge of this moisture
will likely hit the Big Island Thursday through Saturday and focus
showers across the windward and southeast portions of the island.
Some of this moisture may spread far enough north that the trade
winds will carry a small bit of it over the smaller islands.

&&

.AVIATION...
A front will move into the smaller islands today, bringing
numerous to widespread showers and MVFR cigs/vsbys along with it.
Windward areas will have the highest potential for reduced
cigs/vsbys, with some IFR conditions not out of the question. The
front will likely stall out somewhere in the vicinity of Maui
County tonight, keeping unsettled conditions in place here, while
some improvement will be possible over Kauai and Oahu.

Additionally, a few thunderstorms will be possible along and near
the front today and tonight.

Drier conditions will prevail during the next 24 hours over the
Big Island as the front should remain north of the area. A few
convective showers can be expected as a result of daytime heating
however.

AIRMET Sierra is in effect for mountain obscuration over windward
sections of Kauai. This AIRMET will likely be required for
additional areas, including leeward locales later today.

&&

.MARINE...
The southern advancement of a cold front across the northern
Hawaiian offshore waters this morning will maintain moderate to
fresh northeasterlies to the north of this boundary...moderate
trades south of it. As the front nears the islands today,
northeast winds will slightly strengthen over the windward
coastal Kauai and Oahu (possibly Maui) waters. The front will
stall out and dissipate over the state through Tuesday, with
generally moderate easterly trades prevailing through the middle
of the week. The mid to late week regional pressure will remain
weak across the state from a Gulf of Alaska low blocking high
pressure from re-establishing itself north of the area. This will
result in late week light to gentle trades.

The recent moderate size, medium period northwest swell that
lifted surf along the north-facing shores of Kauai, Oahu and Maui
Saturday will shift to a more northerly direction today as it
continues to decline through Monday. The next moderate size,
medium period north to northeast swell originating from a low
northeast of the islands will begin arriving Monday afternoon and
evening. Surf associated with this swell should peak surf below
High Surf Advisory (HSA) levels by late Monday and hold through
Tuesday. A gale in the western Aleutians Sunday will push a north
swell southeast toward the islands the next couple of days. This
slightly larger, medium period swell may reach the state by
Thursday and peak surf to near HSA heights along north-facing
shores Friday. A small, medium period south swell arriving today
will lead to slightly higher south-facing shore surf that will
hold through mid week. Surf along east-facing shores will remain
small through the upcoming week in response to lighter trades over
and upstream of the islands.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
None.

&&

DISCUSSION...Foster
AVIATION...Jelsema
MARINE...Blood