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Area forecast discussion 
National Weather Service Honolulu HI
400 am HST Wednesday Jul 29 2015

Synopsis...
winds will become locally breezy today with passing showers focusing
over windward slopes. Trade winds will persist into the weekend. An
increase in tropical moisture over the weekend will likely bring
additional showers to portions of the island chain.

&&

Discussion...
still rather fair weather prevails across the state early this
morning...with minimal showers in the island vicinity. Latest radar
data did show a smidgen more showers just east of the islands in the
past few hours. These showers...carried by the trade winds...will
reach the islands later in the morning...affecting mainly windward
areas. There are still some high clouds streaming over the islands
at this time...though the amount has decreased quite a bit since
last night. On the other hand...high clouds over the islands may
increase later this morning again as more convection has fired up
just west-southwest of the area in the past few hours. Early morning
Lihue sounding still depicted a rather unstable and somewhat moist
airmass...though Hilo sounding is drier and slightly more stable.
Trade winds are expected to firm up a bit as the day
progresses...since the surface troughs that have been lingering to
the north and northwest of the islands will finally move
away...while a surface high pressure will hold far north of the
area. Forecast solutions continue to show middle to upper level ridging
in the island vicinity. Thus mainly fair weather is expected to
continue today...with some passing low clouds and showers affecting
mainly windward areas.

Trade wind weather is expected to continue through the rest of the
week...as a surface high pressure persists far north of the area.
Low clouds with embedded showers carried by the winds will affect
mainly windward and mountain areas at times...especially at night
and early morning.

An increase in mainly windward rainfall is possible this weekend.
The latest official forecast from National Hurricane Center still
indicates the dissipation of Tropical Depression Eight-east far east of
the state on Thursday. There are still differences in the model
solutions on when and how much remnant moisture from the dissipated
system will reach the area over the weekend. The islands may at
least experience more humid weather...with possible additional
showers for the eastern end of the state.

&&

Aviation...
VFR conditions are expected to prevail across the state today. In
addition...trade winds are expected to strengthen slightly. No
airmets are in effect at this time...though increasing trade winds
may lead to possible airmet Tango for low level turbulence over and
immediate Lee areas of mountains.

&&

Marine...
latest readings from the near-shore buoy just southwest of Oahu
continue to show a steady decline of the current southerly swell.
Therefore...the high surf advisory for all south facing shores is
canceled. The swell will gradually decline further through Thursday.
Short period choppy surf along east-facing shores will slowly build
under the increasing trade winds.

A Small Craft Advisory is posted for the typical windier coastal
waters around The Big Island and Maui today. The advisory is valid
through Thursday but will likely be extended into the weekend for
the same areas.

&&

Hfo watches/warnings/advisories...
Small Craft Advisory until 6 PM HST Thursday for Maalaea Bay-Pailolo
Channel-Alenuihaha Channel-Big Island leeward waters-Big Island
southeast waters.

&&

$$

Hui

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