646
FXUS62 KRAH 251956
AFDRAH

Area Forecast Discussion
National Weather Service Raleigh NC
356 PM EDT Tue Jun 24 2024

.SYNOPSIS...
Weak high pressure will pass over the area today, then push quickly
offshore by this evening, allowing hot and humid conditions to
return for Wednesday. Another front will approach from the northwest
early Thursday, then settle slowly southeast through the Carolinas
Thursday through Thursday night.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 355 PM Tuesday...

The weak area of surface high pressure has moved offshore of the
southern Mid-Atlantic, with a cold front well to our south across
southern GA/SC. Looking aloft, a mid/upper low now centered over
Nova Scotia will lift NE through tonight as ridging builds over the
Deep South. Warming and drying from this ridging is resulting in a
subsident inversion at 700 mb evident again on this morning`s GSO
sounding.

Dry air and good mixing are helping dew points be noticeably lower
than yesterday, as they have dropped to the upper-50s to mid-60s
across much of central NC. This is mostly keeping heat indices in
check. However, the air remains more soupy than expected across far
SE locations like KMEB and KFAY, where dew points are in the lower-
70s and heat indices are in the lower-100s. This is due to SE return
flow around the high which was enhanced by outflow from convection
off the SC coast. So a moisture gradient stretches NE across the
Sandhills and central/southern Coastal Plain. Radar depicts a couple
tiny showers recently popping up over Scotland and Cumberland
counties along this boundary, though they are already diminishing.
SPC mesoanalysis shows 2000-3000 J/kg of SBCAPE from roughly
Scotland County south and east, so added slight chance POPs there
through early this evening. Still not expecting anything widespread
or robust give the dry subsident air aloft.

Tonight will be another warm night with lows in the upper-60s to
lower-70s as the moisture boundary and higher dew points move
inland. This moisture return will help low stratus be possible
late tonight and early tomorrow morning especially in the south.

&&

.SHORT TERM /WEDNESDAY AND WEDNESDAY NIGHT/...
As of 245 PM Tuesday...

Hot with near Heat Advisory criteria...

Hot conditions look to be close to heat advisory criteria for
portions of the eastern Piedmont, Sandhills, and Coastal Plain
Wednesday afternoon and early evening. The heat index numbers
currently indicate that the urban areas around Raleigh and
Fayetteville should top out in the 100-104 range, just short of
criteria. Surrounding areas are a few degrees lower in the 98-101
range for heat indices. Maximum temperatures should top out between
96-100, except 93-96 in the NW-N Piedmont. We will hold off on a
heat advisory for now, but we may need one for Wednesday in later
forecasts, especially for the urban areas around the Triangle and
Fayetteville. Otherwise, mostly sunny and hot conditions under
strong ridging will continue. There may be an isolated thunderstorm
SE Coastal Plain associated with the seabreeze late day.

Another mid level trough will approach late Wednesday night. There
is a slight chance of showers/thunderstorm NW-N overnight, but
chances appear minimal at this time as models suggest plenty of CINH
overnight. Lows will be mostly in the 70s.

&&

.LONG TERM /THURSDAY THROUGH TUESDAY/...
As of 345 PM Tuesday...

Best chance of showers/storms looks to be Thu/Thu night and Sun/Sun
night, both just ahead of mid level northern stream shortwave
troughs and corresponding surface fronts. Temps will stay above
normal through the weekend, esp Thu and Sat/Sun, before moving
closer to normal Mon/Tue.

Thu/Thu night: A northern stream mid level trough will cross the St
Lawrence Valley into New England/Can Maritimes as the tail end of
this front eases SE through the Carolinas, taking a frontal zone
into our area. The greatest chance for overlapping of strong
heating, high PW (near 2"), and decent surface dewpoints will be
across our S and E, where the majority of NBM members have precip in
the afternoon and early evening. Following this, will have a good
chance of showers/storms NW and likely pops across the SE. The deep
layer bulk shear will be rather low at just around 10-15 kts with
marginal mid level lapse rates, and the moderate SBCAPE does shift E
of I-95 late in the day, so expect a decrease in pops in the evening
and mostly dry weather overnight as the mid levels dry out behind
the mid level trough axis. Expect highs in the lower 90s NW trending
to upper 90s SE. Lows in the upper 60s to mid 70s.

Fri/Fri night: The surface front is likely to settle just to our S
Fri morning, then quickly wash out as the surface high to our N
shifts offshore by afternoon. Behind Thu`s shortwave trough, mid
level ridging spreads in from the SW across the Carolinas and
Southeast coast during this time. PW remains well above normal
across our S and SW where low level confluent flow may help organize
scattered afternoon convection, perhaps aided in part by an upslope
low level component. Will carry chance pops, near climo, across the
S and W with little or nothing in the NE, within the exiting surface
ridge. With near normal thicknesses balanced by abundant heating,
temps should be a bit lower than Thu, with highs around 90 to the
mid 90s. Heat index values are projected to be 100-105 over all but
the NW.

Sat-Sun night: Mid level ridging builds further from the S Plains
across the Gulf states Sat through early Sun, as our thicknesses
rise to 10-15 m above normal with deep mixing and warm/dry mid
levels and weak lee surface troughing over the Piedmont. We should
see highs a bit warmer Sat, from the low 90s NW to upper 90s SE, and
will have near-climo pops Sat focused on the W CWA where mountain
convection may drift late in the day. A potent northern stream
trough that moves from the Upper Midwest and across the N Great
Lakes Sat will move through S Que/St Lawrence Valley and into the
interior Northeast Sun/Sun night, and this plus the westward
propagation of the mid level ridge further W into the S Plains and
lower Miss Valley will induce mid level troughing down the Eastern
Seaboard toward E NC. While SBCAPE and deep layer shear will be
marginal Sun, the increasing and deepening moisture (projected PWs
nearly 2.5") and the approaching surface frontal zone both support
higher pops in the good chance to likely range, highest across the N
Sun afternoon through the evening, with the front pushing to our SE
overnight. Expect highs again from the low 90s NW to upper 90s SE
with high dewpoints well into the 70s, indicative of increased heat
stress as heat index values reach 100-110 over nearly the entire
CWA, all but the extreme NW, both days, although confidence is lower
Sun given the potential for clouds and convection.

Mon-Tue: Pops should be on the low side, 10-25% along the S and W,
as surface high pressure builds in from the N within mid level
troughing. Low level thicknesses suggest highs fairly close to
normal, with highs in the upper 80s to lower 90s. -GIH

&&

.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
As of 145 PM Tuesday...

24-hour TAF period: Dry weather and VFR conditions will prevail
across central NC through this evening, with just some scattered
stratocumulus and altocumulus. There could be a very isolated shower
or storm from the sea breeze in the far SE, mainly southern Sampson
County, later this afternoon. Model soundings (including on the RAP,
HRRR and NAM) show potential for IFR or low MVFR stratus late
tonight into early tomorrow morning. The highest confidence of this
occurring is at FAY, but it can`t be ruled out at RDU and RWI
either. Any ceilings will quickly lift and scatter out by mid
morning. Winds will be light (less than 10 kts) and from the S/SE
today, shifting to SW tomorrow morning.

Outlook: IFR-MVFR stratus will be possible especially at FAY and RWI
each early morning from Thu through the weekend. A chance of mainly
afternoon-evening showers/storms will also return to the forecast
for Wed through the weekend, with the relative highest probabilities
at FAY/RWI on Thu. Additionally, the development of an Appalachian-
lee, nocturnal low-level jet across and offshore the Middle Wed
night may result in marginal low-level wind shear in cntl NC during
that time.

&&

.CLIMATE...

Record High Temperatures:

June 25:
KRDU: 100/1952
KFAY: 102/1914

June 26:
KRDU: 102/1952
KFAY: 101/1951

June 27:
KFAY: 102/1998

June 30:
KFAY: 102/2012


Record High Minimum Temperatures:

June 25:
KRDU: 77/2010
KFAY: 75/1952

June 26:
KGSO: 74/2010
KRDU: 76/1902
KFAY: 76/1997

June 27:
KGSO: 76/1969
KRDU: 76/1952
KFAY: 77/1998

June 28:
KGSO: 76/1969
KRDU: 76/1952
KFAY: 78/1914

June 29:
KGSO: 74/2010
KRDU: 78/1914
KFAY: 76/1969

June 30:
KGSO: 74/1936
KRDU: 80/1936
KFAY: 79/1936

July 1:
KGSO: 77/1970
KRDU: 75/2012
KFAY: 76/1990


&&

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

&&

$$
SYNOPSIS...Hartfield
NEAR TERM...Danco
SHORT TERM...Badgett
LONG TERM...Hartfield
AVIATION...Danco/MWS
CLIMATE...RAH