855
FXUS62 KRAH 190723
AFDRAH

Area Forecast Discussion
National Weather Service Raleigh NC
325 AM EDT Thu Sep 19 2024

.SYNOPSIS...
An upper level low over the Carolinas will drift east then
northeast, tracking along the Mid Atlantic and Northeast coast
through Friday. A trailing upper level trough will persist just off
the East Coast through the weekend, as an upper level high pressure
ridge builds over the Gulf States. This ridge will shift east into
the Southeast states early next week.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 915 PM Wednesday...

The bulk of convective activity so far this evening has largely been
associated with the the dampening upper wave/low moving east along
the NC/SC line. In comparison, convection associated with the weak
front draped across the far northern counties has been more sparse.
Only time will tell if this trend will persist, but hi-res model
guidance indicates that both these features will support a
continued chance of isolated to widely scattered activity well into
the overnight hours.

Low overcast will overspread the area from north to south through
the overnight hours. Some patchy fog may be possible, but guidance
has lowered probabilities of fog in favor of mostly stratus.
Overnight lows will settle in the mid/upper 60s for most areas.

&&

.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
As of 305 PM Wednesday...

Aloft, the trough situated over the East Coast should slowly slide
eastward through Thu night, but remain along/just off the East Coast
by Fri morn as high pressure builds over the Plains and MS Valley.
At the surface, a low will meander off the northern mid-Atlantic/New
England Coast Thu/Thu night, while high pressure over the ern Great
Lakes ridges swd along the Appalachians. Meanwhile, the low that has
lingered over the northeast NC coast should shift esewd but linger
just off the central NC coast Thu before moving further southeast
over the Atlantic. Expect generally nly/nely flow across central NC
through Thu night. Some showers may linger into Thu morning over the
Piedmont. There could be a brief lull in activity before additional
scattered showers and isolated storms develop Thu aft, mainly along
lingering surface boundaries. Skies may remain mostly cloudy through
Thu morn and into the aft, which could further limit daytime
heating. Highs should top out in the mid 70s to low 80s, but could
be a couple/few degrees higher if cloud cover decreases earlier that
forecast. While the weather should dry out, there should be
lingering partly to mostly cloudy skies Thu night, with lows
expected to range from upper 50s north to mid 60s south.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
As of 325 AM Thursday...

The weekend into early next week still looks mostly dry, although
rain chances are poised to return by late Tue. Above-normal temps
Sat-Sun will trend to near or a bit below normal Mon-Wed.

Sat-Sun: The mid-upper level trough will hold just to our E off the
East Coast this weekend, while ridging builds from the TX/Mexico
border northeast into the Gulf States and Mid South. A narrow weak
surface high will continue to extend from New England and the
Canadian Maritimes SSW through central NC, held in place by the
persistence of a deep surface low well off the Mid Atlantic coast.
By early Sun, models roughly agree on a weak shortwave trough
originating near Lk Huron tracking SE through the Mid Atlantic
region, dragging a reinforcing backdoor cold front SSW through
central NC. Some deterministic models such as the GFS favor some
shallow showers with this front passage late Sat night/early Sun,
but given that deep moisture will be lacking with a NW low-mid level
flow and below normal PWs, will keep pops under 20% for now.
Whatever showers do manage to form are apt to be very light and
sparse. The backdoor front will usher in some cooler air by late
Sun, but before that, thicknesses suggest highs both days in the
upper 70s to mid 80s, coolest NE.

Mon-Wed: The surface ridge will continue to nose through our area
Mon into Tue, as the surface low drifts steadily S from off the Mid
Atlantic to off the Carolina coast. The mid level ridge from TX into
the Gulf States/Mid South will shift E into the Southeast during the
early work week, nudged by deep mid-upper troughing over central
Canada through the US Plains states. This onset of WSW flow aloft
into the W Carolinas could support rising chances for convection
over the NC mountains and foothills, and perhaps into the W
Piedmont, esp near the old backdoor frontal zone with lift enhanced
by upslope low level flow. Expect mostly dry weather to hold Mon and
through much of Tue, but with improving moisture return in our W,
will bring in 20-30% pops (higher NW and just isolated elsewhere)
late Tue through Wed, still mostly under climatology. Thicknesses
will stay a bit below normal Mon before trending back toward normal
Wed as the resident air mass modifies, but overall expected temps to
be just a shade below normal with increasing clouds. -GIH

&&

.AVIATION /06Z THURSDAY THROUGH MONDAY/...
As of 210 AM Thursday...

A line of showers and isolated storms is currently draped along a
boundary across the southern Piedmont and northern Sandhills, but it
has remained stationary and is beginning to weaken. Guidance
continues to show additional showers developing later tonight into
mid morning around RDU and RWI. MVFR or IFR visibilities will be
possible in any showers. Fog potential continues to look limited at
best tonight given the widespread low stratus across most of central
NC, but it can`t be totally ruled out especially in the far south
(including FAY) where the low stratus will be slowest to reach.
Otherwise, the low stratus is resulting in widespread IFR ceilings
across the north (including INT/GSO/RDU/RWI), and they should lower
further to LIFR over the next 2-3 hours. The IFR/LIFR ceilings
should reach around FAY by 9-10z. Ceilings will gradually lift and
scatter through the day, with MVFR by late morning and early
afternoon, and VFR by late afternoon into the evening. After a brief
lull in precipitation, scattered showers and isolated storms are
possible in the south and east (including RDU, RWI and FAY)
starting in the early afternoon, diminishing after 00z.

Outlook: Areas of overnight and early morning fog/low stratus will
remain possible Fri and Sat mornings, though coverage and chances
appear less compared to previous days. Aviation conditions should
largely trend VFR Sun and Mon. Precipitation chances will be minimal
if any through the period.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

SYNOPSIS...Hartfield
NEAR TERM...CBL/Swiggett
SHORT TERM...KC
LONG TERM...Hartfield
AVIATION...Danco/Kren