828
FXUS62 KRAH 150817
AFDRAH

Area Forecast Discussion
National Weather Service Raleigh NC
315 AM EST Fri Nov 15 2024

.SYNOPSIS...
An upper level disturbance will finish crossing the region today.
Surface high pressure will dominate the eastern United States into
the beginning of next week.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 255 AM Friday...

Surface low pressure is just off Cape Hatteras and will continue to
deepen as it moves east. An upper low near Washington DC will move
southeast and strengthen as it moves offshore this afternoon.
Although the bulk of rainfall has moved offshore, rain still extends
southwest from the Delmarva Peninsula southwest to Rocky Mount. The
rain will slowly shift eastward, not coming to an end in
northeastern counties until after sunrise. As the surface low
deepens off the coast, it will cause an increase in the pressure
gradient between the low and high pressure over the Plains. The
increasing pressure gradient will bring an increase in wind, with
sustained wind speeds around 10 mph and gusts up to 20 mph. Clearing
should gradually occur from west to east through the daytime, while
skies should remain mostly cloudy until nearly sunset in the east.
Due to the differences in cloud cover, highs will be the coolest in
the northeast where the clouds persist the longest, only reaching
the mid to upper 50s. However, with mostly sunny skies most of the
day, southwestern counties should rise into the mid 60s.

With the surface low well offshore by the evening and the high
pressure moving into the Ohio Valley, the wind should relax
overnight, dropping back to 3-5 mph. Skies will remain mostly clear
through the night. Overnight lows will range from the upper 30s to
the mid 40s.

&&

.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
As of 315 AM Friday...

Tranquil weather returns for the weekend as the low pressure system
off the North Carolina coast departs further east and an upper ridge
over the Deep South builds across the eastern US.  High pressure
over the Great Lakes will extend toward the region but will retreat
and eventually be replace by high pressure over the Southeast US.
Thus Saturday will the the start of a transition back toward above
normal temperatures, with highs ranging from the lower 60s in the
northeast to mid 60s in the southwest.  There may be some lingering
moisture beneath a rapidly stregthening subsidence inversion early
in the day, but otherwise mostly clear skies should prevail. Low-
level thicknesses dropping into the 1330m range support overnight
lows Satruday night in the mid 30s in the rural and typically colder
areas under clear and calm conditions.  Some frost concerns may
exist.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
As of 315 AM Friday...

**Above normal temperatures through midweek, followed by a strong
pattern change and potential for below normal temperatures next
weekend.


**Multiple rounds of rain possible mid to late week, but forecast
remains low in the details.


Upper level ridging will continue to build across the eastern US
through early next week.  A surface high pressure will settle across
the southeast US and eventually off the Florida coast. This pattern
will result in high temperatures rising into the upper 60s by Sunday
and low to mid 70s Monday/Tuesday (and possibly Wednesday as well
depending on the timing of the next cold front). Normal high
temperatures for November 1619 are in the low to mid 60s so high
are expected to be as much as 10 above normal.

Forecast confidence decreases significantly during the latter half
of the week as an upper level low is forecast to replace the ridging
over the Eastern US. Initially, an upper low is forecast to lift out
of the southwestern US toward the upper Midwest early in the week.
This will send a lead cold front toward the east coast by Wednesday.
The wave is forecast to be followed by a northern stream wave that
will deepen significantly over the Midwest by Thursday, with a more
significant cold front Thursday that will result in a strong pattern
change with cooler temperatures for next weekend (as advertised by
CPCs 8-14 Day Outlook).

The details of the developing upper low will have significant
impacts on how much rainfall we get with either or both cold fronts.
There appear to be two main clusters within the greater ensemble
guidance; one with a more progressive upper level low/trough that
reaches the Mid-Atlantic states by Friday and another, slower
solution where the trough is back over the Midwest on Friday.  The
ensemble spread appears to be high, and thus guidance indicates high
temperature spread from the lower 50s to mid 60s by Thursday. The
rainfall forecast is further complicated by moisture associated n
part with Tropical Storm Sara, which is not forecast to move into
the Southeast US but some tropical moisture could get drawn north
along the cold front(s).

&&

.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
As of 1235 AM Friday...

TAF period: Widespread IFR/LIFR ceilings remain across central North
Carolina, with RWI the only terminal that is likely to receive any
more measurable precipitation. There is a signal that INT/GSO may
scatter out rather quickly before ceilings rise too much higher, but
have decided to err on the side of caution and keep lower ceilings
in the forecast through sunrise. Farther east, RDU/FAY will likely
remain IFR through the night with ceilings rising after sunrise and
scattering out around noon. Finally, RWI will likely require most of
the daytime for skies to scatter out. The wind will generally be out
of the north-northwest through the period, between 5-10 kt overnight
and into the morning before afternoon gusts develop between 15-20
kt. Gusts should end around sunset, but remain out of the northwest
between 5-10 kt and will likely diminish further later in the
evening.

Outlook: Dry VFR conditions are expected through early next week;
the next chance of rain will occur after the outlook period
concludes.

&&

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

&&

$$

SYNOPSIS...Green
NEAR TERM...Green
SHORT TERM...BLS
LONG TERM...BLS
AVIATION...Green