488
FXUS62 KRAH 271935
AFDRAH

Area Forecast Discussion
National Weather Service Raleigh NC
335 PM EDT Thu Mar 27 2025

.SYNOPSIS...
Canadian high pressure over the Carolinas will drift offshore
through tonight. A warm front will lift northeast across the Middle
Atlantic on Friday, with following Bermuda high pressure that will
extend across the South Atlantic states through the weekend.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 320 PM Thursday...

A mid-level sub-tropical high over the nrn Gulf will drift ewd and
across and offshore the South Atlantic states, while a Canadian
surface high, and associated continental air now centered over SC
and sern NC, will drift offshore.

After a continued sunny afternoon and clear evening, the ern flank
of a warm advection wing of 700 mb-centered saturation from the upr
Midwest to the OH Valley will stream across the Virginias and
especially nrn NC overnight-Fri morning. While it may be accompanied
by a little virga, it will be falling from ~8-10 thousand ft
ceilings atop a deeply dry sub-cloud layer; and none should survive
to the surface. In addition to the increasing clouds, light swly
stirring should help keep low temperatures in the 40s.

&&

.SHORT TERM /FRIDAY AND FRIDAY NIGHT/...
As of 310 PM Thursday...

A mid-level sub-tropical high over the nrn Gulf will drift ewd and
across and offshore the South Atlantic states, while a shortwave
trough now over nwrn Mexico will migrate ewd and deamplify by the
time it reaches the lwr MS Valley Sat morning. Between the two,
initially thin cirrostratus will overspread cntl NC Fri afternoon-
evening, then thicken and lower to around 500 mb overnight-Sat
morning.

At the surface, ~1028 mb high pressure now centered over SC and sern
NC will drift ewd and become centered near Bermuda for the next few
days. A warm front will meanwhile retreat newd across the OH Valley,
then become quasi-stationary across the lwr Great Lakes and nrn
Middle Atlantic Fri night-Sat morning. Warm, sly to sswly flow will
result across cntl NC.

The pattern noted above will favor well above average temperatures
(10-20 F) in the upr 70s to around 80 Fri, accompanied by a swly
breeze that will gust to 20-25 mph, followed by mostly mid-upr 50s
Fri night. Low-level moisture recovery, characterized by surface
dewpoints in the 50s, likely will not occur in cntl NC until Fri
night. That moistening may support the development of areas of
stratus early Sat morning, in addition to the increasing mid/high-
level moisture noted above.

&&

.LONG TERM /SATURDAY THROUGH THURSDAY/...
As of 239 PM Thursday...

Upper pattern through the extended: A weak short-wave will traverse
the TN Valley Saturday before washing out over the Appalachians
through Sunday morning.  A deeper trough will then lift across the
eastern seaboard Sunday through Tuesday. Beyond Tuesday, guidance
diverges, with the ECMWF depicting enhanced ridging over the eastern
US while the GFS depicts a strong mid-week short-wave.

Saturday through Tuesday: The western ridge of an anchored, offshore
sfc high will promote continued sly flow across central NC Saturday
and Sunday.  On Saturday, anomalous moisture and associated stronger
isentropic upglide will largely remain west of our area. As such,
most of Saturday should remain dry with warm daytime highs reaching
the upper 70s to lower 80s.

POPs will increase from west to east later Saturday night into early
Sunday as the aforementioned washed out upper wave and associated
perturbations/moisture moves through our area.  QPF with this round
should be limited (Sunday 12Z through Monday 12Z), with median
ensemble QPF of a few hundredths to a few tenths (90th percentiles
max out around a half inch). Models show at least a bit of
instability possibly developing Sunday afternoon, but for now, think
thunder chances should be fairly limited Sunday.  Highs on Sunday
will reach the upper 70s.

After a little lull Sunday evening, POPs will increase again from
west to east early Monday as pre-frontal showers/storms move across
our area. Guidance is in pretty good agreement with the best upper
forcing moving over our area Monday afternoon and evening. As such,
have trended highest POPs during this period.  While there remains
some uncertainty wrt to severe storm potential Monday, ensembles do
seem to be trending towards shunting the best shear/CAPE combo to
our south.  Will have to keep monitoring as we get closer, but this
may also limit QPF amounts Monday into Tuesday over central NC as
well.

Wednesday/Thursday: As was mentioned above, guidance splits on
middle of next week wrt to the upper pattern. As such, decided to
maintain low POPs in this time frame for now. After cooler early to
mid week temps in the 70s, we could see a good warm up heading into
later next week.

&&

.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
As of 155 PM Thursday...

The influence from dry, Canadian high pressure that will drift off
the coast of the Carolinas by tonight will favor continued VFR
conditions in cntl NC through Fri. A little virga may accompany a
band of mid-level, 8-11 thousand ft AGL ceilings that will
overspread cntl NC overnight-Fri morning, but with no operationally
significant impacts at the surface.

A modest low-level jet and related strong temperature inversion
tonight will also favor marginal low-level wind shear conditions
overnight-Fri morning, especially along the axis of the jet near RDU
and GSO. Swly surface winds will then strengthen and become gusty to
around 20 kts with daytime heating by mid to late morning Friday.

Outlook: Low-level moisture will increase, characterized by surface
dewpoints in the 50s, such that areas of IFR stratus will be
possible both Saturday and Sunday morning. Additionally, a nocturnal
low-level jet coupled with a modest temperature inversion will
promote a risk of marginal low-level wind shear conditions this
weekend. A chance of showers and storms will return Sun and
especially with the passage of a cold front on Mon.

&&

.FIRE WEATHER...
As of 335 PM Thursday...

* Increased fire danger remains in effect through this evening.

* Increased fire danger has been coordinated with NCFS and
  surrounding NWS forecast offices for Fri; and the SPS statement
  will be issued this evening.

Low afternoon RH values mostly between 15 and 25 percent, occasional
wind gusts up to 15-20 mph, and dry fuels will yield increased fire
danger this afternoon.

While surface dewpoints are expected to increase Fri, temperatures
will also warm. As a result, afternoon RH will be continued low and
in the mid 20s to around 30 percent. Additionally, swly winds will
strengthen and become more-frequently gusty to around 20-25 mph.
Increased fire danger will result.

Low-level moisture recovery, with min RH mostly between 35-45
percent Sat, 45-55 percent Sun, and 55-65 percent Mon, along with an
increasing probability of showers/storms Sun-Mon, should gradually
lessen the fire danger threat this weekend-early next week.

&&

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

&&

$$
SYNOPSIS...MWS
NEAR TERM...MWS
SHORT TERM...MWS
LONG TERM...Luchetti
AVIATION...MWS
FIRE WEATHER...MWS