Drought in Hawaii, June 15 to 30, 2021

Area Forecast Discussion
National Weather Service Honolulu HI
831 PM HST Mon Jun 14 2021

.SYNOPSIS...
High pressure north of the state will keep moderate to locally
breezy trades in place through Friday. Fairly dry trade wind
weather will prevail through Tuesday morning, with the remnants of
an old front bringing an increase in shower coverage and intensity
to Kauai and Oahu Tuesday afternoon through Wednesday. A more
typical trade wind shower pattern will resume Wednesday night and
hold through early next week, with showers favoring windward and
mauka areas and a few showers reaching leeward communities from
time to time.

&&

.DISCUSSION...
Currently at the surface, a 1027 mb high is centered around 950
miles north-northeast of Honolulu, and is driving moderate to
locally breezy trade winds across the island chain this evening.
Infrared satellite imagery shows quite a bit of high cloud moving
overhead, while the leading edge of a roughly 100 mile wide cloud
band (the remnants of an old front) are evident around 100 miles
north of the smaller islands. Radar imagery shows scattered
showers over windward Big Island and a few isolated showers along
the leeward Big Island slopes. Elsewhere, very little shower
activity is seen, with perhaps a few showers developing over the
coastal waters east and northeast of Kauai. Main short term
concern revolves around the rain chances associated with the old
frontal remnants during the next couple days.

High pressure will build eastward well to the north of the islands
during the next few days, while a weak disturbance slides westward
well to the south of the state. This will keep moderate to locally
breezy trades in place through Friday. A front is then expected
to approach from the northwest Friday night and Saturday, then
stall out several hundred miles northwest of the islands Sunday
through early next week. As a result, we should see the trades
ease into the light to moderate range Friday night and Saturday,
and hold at similar levels Sunday into early next week.

As for the remaining weather details, expect a fairly dry night
across the island chain with a few windward showers mainly
affecting Kauai and the Big Island, and sparse shower coverage
elsewhere. The old frontal remnants are expected to bring an
increase in showers particularly to windward sections of Kauai and
Oahu beginning Tuesday morning, with fairly wet trade wind
weather then holding through Wednesday for these two islands,
although some improvement is expected over Oahu Wednesday
afternoon. Showers will favor windward and mauka areas, but a few
showers will also reach leeward communities. Drier trade wind
weather will prevail over Maui County and the Big Island, with
mainly windward showers.

A disturbance aloft will move southward over or just north of the
state Wednesday night and Thursday, then meander in the vicinity
of the islands through early next week. Overall, this should
bring an increase in trade wind shower coverage and intensity
Thursday through early next week. Showers will continue to favor
windward and mauka areas, but the elevated inversions will likely
send a few more showers into leeward areas as well. Additionally,
a thunderstorm or two could develop over the Big Island Thursday
afternoon.

&&

.AVIATION...
High pressure north of the state will continue to bring moderate
east northeast trades across the islands for the remainder of the
night. Isolated to scattered showers will be limited to windward
locations with brief periods of MVFR ceilings and visibility
possible. Expect VFR conditions and partly cloudy skies elsewhere.

No AIRMETS are currently in effect.

&&

.MARINE...
High pressure north of the islands will maintain moderate to
fresh trade winds through the week. Winds may reach Small Craft
Advisory thresholds at times around Maui and the Big Island. Trade
winds may decrease over the weekend as a front develops well
northwest of the state.

Surf along south facing shores will remain small through Wednesday,
then slowly rise, approaching High Surf Advisory levels over the
weekend. A short-period north swell will produce small surf along
north facing shores Tuesday through Wednesday night. Surf along
north facing shores will be minimal through the rest of the week,
but a small northwest swell is possible early next week. Trade
winds upstream of the islands will produce only small and choppy
surf along east facing shores.

&&

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

&&

DISCUSSION...Jelsema
AVIATION...Thomas
MARINE...Morrison