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000
FXUS62 KILM 121935
AFDILM

Area Forecast Discussion
National Weather Service Wilmington NC
335 PM EDT Wed Aug 12 2020

.SYNOPSIS...
High pressure extending westward toward the Carolinas from the
central Atlantic will maintain southerly winds along with
seasonably warm and humid conditions. Weak trough of low
pressure over the area will produce greater coverage of storms
into the weekend, but will diminish into early next week as
trough moves offshore late Sunday into Monday.

&&

.NEAR TERM /THROUGH THURSDAY NIGHT/...
Mid-level troughing to the west today will remain in place Thu,
pumping an abundance of Gulf moisture over the region. Bermuda High
and Piedmont trough will also contribute to broad southwest flow and
enhanced low level moisture advection. Precipitable water around 2.1
inches today will rise to 2.3 to 2.4 inches later Thu and Thu night.
Combine the deep moisture with CAPE in the neighborhood of 2500
J/kg, storm motion under 5 kt and a very deep warm cloud layer and
the result will once again be storms capable of excessive rainfall.
Coverage remains limited this afternoon and evening, but will
increase on Thu. Weak trough in the vicinity today and Thu with
hints of one, and possibly more, weak surface wave(s) developing
along the trough Thu. The increase in low level convergence should
help increase storm coverage Thu afternoon/evening. An increase in
marine convection Thu night compared to tonight is also likely given
the presence of the aforementioned surface wave(s). Increase in
clouds and storms will keep highs near to slightly below climo. Lows
will run several degrees above climo.

&&

.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
A lingering trough will remain over the Carolinas as low
pressure lifts north on Friday. At the same time, the mid to
upper trough extending down just east of the Mississippi Valley
will dig southward as it shifts eastward through Saturday. These
two features along with localized boundaries including sea
breeze and an abundance of moisture, will all contribute to a
bit more widespread coverage of thunderstorms both Fri and Sat.
Pcp water values will be over 2 inches. By Sat aftn the sfc
boundary seems to lift more inland and north leaving a stiff SW
flow. This should focus better coverage over NC, but upper
trough will be aligned with the best shortwave energy running up
from the SW to W right over our forecast area. May see
convection running into the night as trough shifts slowly
eastward. Overall, expect hot and humid weather to continue with more
widespread clouds and convection Fri into the weekend and temps
up around 90 during the day and 70s overnight.

&&

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
Mid to upper trough continues to shift eastward with shortwave pushing
a sfc front eastward and both reaching off the Southeast coast
later on Sunday. Overall, expect winds to shift around to the
W-NW and with limited coverage of tstorms Sun night into Mon in
a more zonal flow aloft. Pcp water values up near 2 inches early
Sun morning will be down near or less than 1.5 inches by late
Sun through at least Mon. Dewpoint temps should drop several
degrees Sun night into Mon.

By midweek, the trough becomes more amplified again, as it digs
down from the Great Lakes down to the Gulf coast. Shortwaves
will rotate around up the upper trough through the Southeast
allowing for greater coverage of storms once again Tues or Wed
through midweek.

&&

.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
Some light to moderate convection this afternoon into early evening.
Given the wind direction, most of the convection will be inland as
the resultant pushes west. Some isolated fog after midnight, with
some MVFR ceilings possible by daybreak.

Extended Outlook...TSTMs, isolated to scattered will continue for
the next 7 days. Patches of morning fog generally between 8z-11z
should be expected, or localized MVFR stratus. Winds outside of
TSTMs should remain light, and southerly.

&&

.MARINE...
Southerly flow continues into Thu before winds become more southwest
as remains of weak surface trough push inland. Gradient tightens up
a bit Thu with speeds increasing from 10 kt or less this afternoon
and evening to 10 to 15 kt Thu and Thu night. Nocturnal convection
is expected both tonight and Thu night, although coverage is likely
to be higher Thu night. Seas run 2 to 3 ft through Thu and could
bump to 2 to 4 ft Thu night. Southerly wind wave will continue to be
dominant over a weak southeast swell.

S-SW flow will continue Fri through the weekend. Enhanced
troughing over NC will push winds up a bit Fri into the weekend,
which in turn will kick seas up a bit. Overall, expect seas in
the 2 to 4 ft range, but may see a few 5 fters in the outer
waters, especially on Fri. Winds should veer around to the W-NW
as a weak front/trough moves through the waters from west to
east late Sun into Mon morning. Expect increased coverage of
thunderstorms this weekend. Coverage should decrease slightly by
early next week after front/trough moves through.

&&

.ILM WATCHES/WARNINGS/ADVISORIES...
SC...None.
NC...None.
MARINE...None.

&&

$$
SYNOPSIS...ILM
NEAR TERM...III
SHORT TERM...RGZ
LONG TERM...RGZ
AVIATION...III/43
MARINE...III/RGZ