Area Forecast Discussion
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FXUS62 KILM 230804
Area Forecast Discussion
National Weather Service Wilmington NC
404 AM EDT SAT JUL 23 2016
A ridge of high pressure will expand across the Carolinas bringing
increasingly warm temperatures through the weekend. This heat
wave will continue through much of the upcoming week.
.NEAR TERM /THROUGH TONIGHT/...
As of 400 AM Saturday...Impressively large ridge aloft will
dominate the southern half of CONUS while gradually building over
the eastern seaboard. Flow aloft will keep the upper levels quite
dry. At the surface the Bermuda high will continue to dominate,
bringing a very moist and warm south to southwesterly flow to the
region through the near term. Temperatures will climb above normal
and with dewpoints in the 70s we can expect heat indices this
afternoon to range from around 100 to 104F. lack of both moisture
aloft and strong forcing will greatly limit coverage of convection
today. However, there are some indications that a broad, weak
short-wave will drop across the region today, so do have isolated
convection area-wide for the afternoon and evening hours.
Otherwise, we can expect isolated sea- breeze forced convection
along the coastal counties.
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
As of 400 AM Saturday...A hot and humid airmass will continue to
dominate the eastern Carolinas as broad ridging prevails aloft and
the Bermuda high persists at the surface. Both days will feature
afternoon heat index values exceeding 100F, with a Heat Advisory
quite possible for Sunday. Much like on Saturday, very dry air aloft
and lack of strong forcing will limit convective coverage to
isolated storms each day, primarily along the sea breeze front and
any other boundries that happen by.
.LONG TERM /TUESDAY THROUGH FRIDAY/...
As of 330 AM Saturday...Overall, Bermuda High and Piedmont
trough will be the main players in forecast much of the week.
Therefore persistent S-SW winds will continue to feed warm and
moist air into the area with potential for localized shwrs/tstms
each day. The upper ridge helping to keep convection more limited
will break down a bit into mid week as a northern stream trough
digs down as it pushes a cold front south and east. Although the
front does not look like it will make it, it will drop south into
North Carolina which in turn may help to increase the gradient
flow and localized convergence around the Bermuda High and
Piedmont trough inland. It will also turn the N-NE upper level
flow around the east side of ridge extending into the Carolinas
from the Midwest to a more W-NW flow aloft, around base of
stretched out upper trough extending down from the north. Should
also see a bit more in the way of clouds and convection reaching
into area from upstream. Do not expect much in the way of upper
level support as Atlantic ridge builds quickly back in from the
east by Thurs/Fri.
By mid week, the influence of the front to the north and
retreat of ridge extending in from the Midwest should increase
chc of convection and clouds across the area which may shave a few
degrees off the max temps. But ridge builds back in from Atlantic
and overall expect very warm temps most of the week. Right now, it
looks like heat advisory conditions may exist over several days
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
As of 06Z...VFR at TAF issuance time at all terminals. Lingering
high clouds streaming in from the north across mainly inland areas.
Confidence is high for VFR through sunrise, although where rainfall
occurred last evening at KLBT there is a chance of MVFR vsbys
despite 20kt boundary layer winds. Models continue to show another
impulse moving down in the deep northerly flow aloft tomorrow
which may combine with localized shwrs/tstms possible due to sea
breeze front and piedmont trough inland. Timing should be aftn
into eve with convection at terminals, but overall confidence is
low. Therefore included a Prob30 group in most TAFs. Winds will
be WSW, but will back to the SSW- SW by mid- late morning.
EXTENDED OUTLOOK...Brief periods of MVFR/IFR from isolated
afternoon convection Sunday through Wednesday. Otherwise expect
NEAR TERM /THROUGH TONIGHT/...
As of 400 AM Saturday... The Bermuda High over the western
Atlantic will keep winds from the SW at 10 to 15 kts, with seas of
2 or 3 ft through the near term.
SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
As of 400 AM Saturday...High pressure over the western Atlantic
will continue to keep winds from the SW at 10 to 15 kts through
much of the the period, with seas of 2 or 3 ft.
LONG TERM /TUESDAY THROUGH WEDNESDAY/...
As of 330 AM Saturday...South to southwest winds will continue
around the Bermuda High. Winds will generally stay in the 10 to
15 kt range with a slight spike in late aftn into early eve,
enhanced by the sea breeze and piedmont trough. By late Wed
gradient will tighten as cold front drops into North Carolina.
This should increase winds and seas Wed night. Overall expect seas
2 to 3 ft but increasing slightly through Wed up to 3 to 4 ft and
may see a few 5 fters in outer waters in stiffer 15 to 20 kt SW