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fxus62 kilm 170626 
afdilm

Area forecast discussion
National Weather Service Wilmington NC
226 am EDT Wed Jul 17 2019

Synopsis...
heat and humidity will continue into early next week as ridging
from high pressure anchored well offshore from the southeast
U.S. Coast, extends inland across Florida. Showers and
thunderstorms will be isolated at first but they will become
more widespread next week. A cold front will arrive and break
the heat Tuesday or Wednesday.

&&

Near term /through Thursday/...
as of 300 am Wednesday...main concern for the next 36 hours is
afternoon high heat indices that could result in heat illnesses.

Building high pressure aloft and southerly wind flow at ground level
will allow afternoon temperatures to rise into the mid to upper 90s
inland, with values closer to the coast in the upper 80s to lower
90s. Regardless of how high afternoon temperatures actually reach,
the combination with dew points in the mid to upper 70s will result
in afternoon heat indices up to 106+ for many locations. Heat
illnesses are possible for those spending time outdoors during the
hours of 12 PM to 7 PM this evening.

Afternoon instability remains across the area today with plenty of
afternoon heating, which will likely lead to another round of
isolated showers and thunderstorms during the peak afternoon
heating. Latest short term high resolution guidance also hints at
precipitation development, but with lack of upper level wind, storms
are not expected to be severe.

Heat and chances for afternoon showers and thunderstorms continue to
be the headlines in the forecast for Thursday.

&&

Short term /Thursday night through Friday night/...
as of 300 am Wednesday...mid level ridging will be broad and
expansive through the period across a good part of the country. It
will not be strong enough to cap all convection however and there
may even be some weak shortwave energy that drops in from the
northwest. The seabreeze shouldn't progress too far inland but will
serve as a convective initiation mechanism as will the well defined
inland Piedmont trough. Pops will thus be fairly uniform across the
area and as usual will have a diurnal/afternoon maximum (though
there may be enough shortwave energy Thursday night for a less than
normal diurnal decrease in storms, at least compared to Friday
night). Temperatures will be elevated a few degrees above
climatology but high dewpoints will once again offer up advisory-
worthy heat indices.

&&

Long term /Saturday through Tuesday/...
as of 300 am Wednesday...mid level ridge/surface Piedmont trough
will be in place over the weekend, though the former weakens on
Sunday. Interestingly guidance is not suggesting any increase in quantitative precipitation forecast
on Sunday. The inherited forecast didn't either and so no tweaks to
pops have been made. Afternoon heat advisories seem likely once
again both days. Monday and Tuesday will bring about a gradual
pattern change as a trough tries to get established in the eastern
US. Thunderstorm coverage should increase on Monday as the
suppressing effects of the mid level ridge wanes but temperatures
will remain hot enough that yet another heat advisory appears
likely. Even higher rain chances slated for Tuesday as cold front
approaches while increased cloud cover should finally preclude a
heat advisory.

&&

Aviation /06z Wednesday through Sunday/...
as of 06z...VFR for area terminals for the next 24 hours.
Showers and thunderstorms expected to develop in the afternoon
hours in the vicinity of airports with moderate confidence in
development, but low confidence on actual locations of afternoon
storms.

Extended outlook...VFR conditions are expected outside any isolated
to widely scattered convection the first part of the upcoming
week.

&&

Marine...
light southerly winds with afternoon gusts up to 20-25 kts as sea
breeze circulation develops for the next 36 hours. Wave heights
between 2 to 4 feet expected out of the southwest around 4 to 6
seconds with swell from the southeast around 10 seconds.

Winds will remain out of the southwest Thursday night through Friday
night as high pressure remains well offshore. A well defined
Piedmont trough will bolster wind speeds by about a category, which
should maintain the offshore 4 ft wave. The mainly wind driven seas
will coexist with a 2 ft 9 second southeasterly swell. Previous
forecasts had very slightly weaker winds Saturday and Sunday but now
this is less certain. The trough may maintain its strength and so
winds may as well. Have trended the forecast accordingly. Weekend
seas will remain similar to those during the week.

&&

Ilm watches/warnings/advisories...
SC...heat advisory from 11 am this morning to 7 PM EDT this evening
for scz017-023-024-032-033-039-054>056-058-059.
Beach hazards statement from 6 am EDT this morning through
this evening for scz054-056.
NC...heat advisory from 11 am this morning to 7 PM EDT this evening
for ncz087-096-099-105>110.
Beach hazards statement from 6 am EDT this morning through
this evening for ncz106-108.
Marine...none.

&&

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