Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Honolulu HI
830 PM HST Monday Jul 28 2014
high pressure far northeast of the state will maintain moderate to
locally fresh trade winds across the islands. Showers carried by the
trades will affect mainly windward and Mauka areas for the next
several days. A surge in moisture from the southeast could bring an
increase in showers and more humid conditions late in the week.
fair weather continues over the islands under moderate trade winds.
Satellite imagery revealed there are only a few low clouds in the
island vicinity this evening...while radar data only have a few
speckles of returns. Satellite imagery did show some more low clouds
east of the islands. These clouds...carried by the trade
winds...will reach the islands later this evening into early
Tuesday morning...and may provide brief showers to mainly windward
and mountain areas.
A surface high that provides the trade winds will remain nearly
stationary far northeast of the state through the week. The
tightening of the pressure gradient across the islands due to low
pressure well to our south has resulted in an increase of the winds
across the area. Trade winds have already increased a bit earlier
today...and will firm up slightly more Wednesday. As forecast models
continue to suggest a rather dry air mass to persist for the next
couple of days...expect Summer trade wind weather to prevail...with
passing showers focusing mainly across windward and Mauka areas.
Winds will locally be breezy at times.
A change in the weather is still expected by the end of the
week...as a surge in tropical moisture from the southeast may spread
across the islands. Forecast models hint a weak upper trough will be
in the island vicinity at about the same time...though model
precipitation amounts forecasts do not look that impressive.
Regardless...humid and wet weather may return to the islands this
week...and may reach The Big Island late Thursday into Friday...then
spread across the rest of the state during the weekend.
convection along the Lee slopes of Mauna Kea and Mauna Loa have
dissipated as expected this evening. Elsewhere...there are only a
few low clouds in the island vicinity. Therefore VFR conditions
will prevail for the sites for the rest of the evening into early
Tuesday morning. There may some brief passing showers bringing isolate
MVFR ceiling condition mainly for windward and Mauka areas.
Moderate to locally gusty trade winds will persist. Therefore airmet
Tango remains in effect for low level turb in the Lee of the terrain.
a Small Craft Advisory continues for the typically windier coastal
waters near Maui and The Big Island this evening. As the moderate
trade winds prevail...expect this advisory to persist over the
affected areas through at least Wednesday.
A series of small southerly swells will reach the islands through
the week. A larger south swell arriving on Friday afternoon may
bring near to above normal surf for south facing shores by Saturday.
Short period trade wind swell will continue across east facing
shores...possibly increasing a bit through the week as trades
Small Craft Advisory until 6 PM HST Wednesday for Maalaea Bay-
Pailolo Channel-Alenuihaha Channel-Big Island leeward waters-Big
Island southeast waters.