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Area forecast discussion 
National Weather Service Honolulu HI
330 am HST Wednesday Jul 27 2016

Synopsis...
high pressure building north of the state will keep a moderate to
breezy trade wind flow in place through the week. Relatively dry
and stable trade wind weather will prevail through Friday, with a
more showery trade wind pattern expected this weekend into early
next week.

&&

Discussion...
currently at the surface, a 1028 mb high is centered around 1800
miles to the northeast of Honolulu, driving the moderate to breezy
trade winds across the Aloha state. Infrared satellite imagery
shows clear to partly cloudy skies in place in leeward areas and
partly to mostly cloudy skies across windward areas. Meanwhile,
radar imagery continues to depict very little in the way of
shower activity across the area. Main short term concern for the
next several days revolves around rain chances.

Today through Friday...
high pressure will strengthen to the north of the island chain,
and this will keep a breezy trade wind flow in place through the
remainder of the work week. Inversion heights will remain low with
precipitable water values near to below climatological norms
through the period. As a result, the amount of trade wind shower
activity will remain suppressed, with clouds and light showers
focused primarily over windward and Mauka areas. Although
temperatures will remain near to slightly above normal, the
breezy trades and comfortable humidity levels will result in a
very pleasant stretch of mid Summer weather.

Friday night through next Tuesday...
model solutions are in good agreement showing high pressure
remaining nearly stationary to the north of the state through the
period, keeping a moderate to breezy trade wind flow in place.
Guidance also shows lowering upper level heights and increasing
moisture, the remnants of Georgette, getting caught up within the
trade wind flow over the weekend. As a result, we should see a
more active and showery trade wind pattern this weekend, with a
more typical trade wind regime returning for early next week.
Clouds and showers will continue to favor windward and Mauka areas
through the period.

&&

Aviation...
trade winds will increase across the islands today and tonight,
with a dry and stable airmass remaining in place. VFR conditions
will prevail, with areas of low clouds and isolated MVFR ceilings
over windward areas.

Airmet Tango for moderate low level turbulence is in effect for
the mountain terrain and immediate downwind areas of The Big
Island and Maui. This airmet may need to be expanded to cover the
other islands later today as the trade winds strengthen.

&&

Marine...
high pressure north of the state will keep a breezy trade wind
flow in place across the marine area through the forecast period.
A Small Craft Advisory is in effect for most marine zones from
the leeward Oahu waters eastward, through Friday. The Small Craft Advisory may need
to be expanded to include additional marine zones tonight or
later in the work week, as the trade winds strengthen a bit more.

Breezy trade winds will result in elevated short period choppy
surf along east facing shores, but surf heights are expected to
remain below advisory levels. There will also be a series of small
southerly swells through the week and into the upcoming weekend.

&&

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

&&

$$

Discussion/marine...jelsema
aviation...Jacobson

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