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Area forecast discussion 
National Weather Service Honolulu HI
405 PM HST Thursday Mar 5 2015

Synopsis...
cool and breezy northeast trade winds will prevail through
Saturday. A stable atmosphere will focus showers over the windward
slopes into the weekend. Enhanced moisture will linger just south
of the state and may bring increasing showers to Maui and The Big
Island late Sunday and Monday. Northeast winds will diminish
Sunday and turn north Monday.

&&

Discussion...

High clouds associated with an exiting upper level trough have
finally exited east of The Big Island. Gusty north-northeast winds are
bringing a cool airmass over the state with showery low clouds
pushing into windward areas. Northeast trades will continue into
the weekend with showers mainly affecting windward areas. High
temperatures will dip below normal through the weekend with highs
only reaching the middle to upper 70/S in most areas. Night time temperatures
will drop below normal Sunday and into next week as dew points
drop further and winds weaken allowing for increased radiational
cooling. The decreasing winds are expected Sunday as a surface
trough forms north of The Big Island and an upper trough swings in
from the northwest over the state. The weakening winds will allow
tropical moisture to again infiltrate The Big Island and possibly
Maui... increasing the chance of rain with the possibility of
heavy showers. Drier weather will remain over the western half of
the state.

A large-scale low aloft will persist north of the islands through
next week. The most active weather will come as short wave troughs
pinwheel around the parent low and swing by the islands from the
northwest. Models are in fair agreement with the Sunday/Monday
shortwave discussed above with less agreement for a short wave
coming through Wednesday/Thursday. The trough aloft will increase
winds over The Big Island summits over the next few days bringing
the potential for a long-lived wind warning starting over the
weekend and continuing into next week.

&&

Aviation...
airmet Tango in effect for high level moderate turb due to strong winds
aloft across the state...but will likely be dropped at 04z. An
airmet Tango is also in effect for moderate low level turb over leeward
Kauai which will likely remain in effect at least until Friday due
to strong trade winds.

Passing trade wind clouds and showers will produce isolated MVFR
ceilings and brief mountain obscure over windward slopes. Otherwise VFR
conditions should prevail tonight.

&&

Marine...
a Small Craft Advisory remains in effect for strong trade winds
and rough seas over the windier coastal waters around the state.
A moderate... short period north-northeast swell will continue into Friday and
then slowly diminish over the weekend. A small northwest swell will
linger through the weekend. A north swell arriving Sunday may
produce advisory level surf along north facing shores Monday.



&&

Hfo watches/warnings/advisories...
Small Craft Advisory until 6 am HST Saturday for Kauai northwest
waters-Kauai leeward waters-Kauai Channel-Oahu leeward waters-
Kaiwi Channel-Maui County leeward waters-Maalaea Bay-Pailolo
Channel-Alenuihaha Channel-Big Island leeward waters-Big Island
southeast waters.



&&

$$

Morrison...discussion and marine
Foster...aviation

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