-- Discussion containing changed information from previous version are highlighted. --
998
FXUS62 KRAH 250553
AFDRAH

Area Forecast Discussion
National Weather Service Raleigh NC
153 AM EDT Sat May 25 2024

.SYNOPSIS...
Above normal temperatures and unsettled weather are expected through
the holiday weekend, with Sunday expected to be the day with the
smallest chance for rainfall. Cooler and drier weather is expected
by the middle of next week.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 750 PM Friday...

Latest analysis shows two shortwaves of interest in the mid-levels.
The first is presently over eastern NC and southeastern VA. At the
surface tied to this feature are some subtle surface troughs, one
moving south into the VA/NC border near the northern Coastal Plain.
The second trough stretches from the eastern Sandhills to roughly
the central Coastal Plain. Convection continues to fire along and
east of these trough features. The convection over the central and
southern Coastal Plain should continue to drift to the east over the
next hour or so, exiting central NC as the mid-level energy pushes
east. The convection moving SSE toward Roanoke Rapids is weakening
as it moves south, into an area of little effective shear but CAPE
still upwards of 1500 J/kg. A low-end chance of showers/storms will
exist for the next few hours, into late evening, over the northern
Coastal Plain as a result, with some convection firing along the
outflow. Storms should not be severe given waning instability and
weak shear.

The second shortwave is roughly over the TN valley, with convection
currently over much of SC. Models take this feature eastward
overnight, reaching the west/southern Piedmont toward the early
morning hours of Sat. Some of the CAMs, such as the HRRR, kick off
some isolated showers or storms in this region, but confidence is
low on coverage, if any, given convective minimum and increasing
CIN. For now, we left slight chances in the southern Piedmont.

There will be the potential for fog over the NE Piedmont to
central/northern Coastal Plain, though little rain has fallen over
the Coastal Plain so confidence is low on placement and extent, if
any. High clouds spreading east from SC may also limit radiational
cooling. Lows are expected to range in the low to mid 60s.

&&

.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
As of 240 PM Friday...

There are lower chances of thunderstorms Saturday, but hot
temperatures expected.

A remnant MCV may be over portions of southwest or far southern NC
at the start of Saturday. The flow aloft would support this MCV
tracking ESE into southern NC or upstate SC Saturday. In addition,
weak surface troughing will hold across our Piedmont with mid/upper
troughing. Strong surface heating will aid in temperatures reaching
the 87-92 range most areas. With high moisture through the column
and higher than average dewpoints in the mid 60s to around 70,
isolated to scattered thunderstorms are possible with heating, with
highest chance across the southwest, south, and southeast zones or
per the track of the remnant MCV and near the surface boundary. Some
of the latest hi-res models suggest that much of the convection
Saturday afternoon may be over GA/SC with a minimum over NC. This
trend will be monitored. Otherwise, isolated to scattered
thunderstorms are expected to diminish Saturday evening. Lows will
be generally 65-70.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
As of 245 PM Friday...

Low pressure will move from the central Plains Sunday morning to the
Great Lakes Monday morning, and it appears the relative lull in
precipitation should continue Sunday. Will keep just an isolated
chance of a shower/storm in the forecast during the daytime, and
pops will only increase slightly Sunday night as a cold front enters
the Mississippi River valley. The cold front now appears likely to
cross the region late Monday afternoon, although the highest pops
will still remain to the north where the better dynamics will occur.
There could be a severe threat with the thunderstorms, considering
favorable low-level lapse rates and CAPE values over 1000 J/kg,
although shear to organize storms appears to be on the low side.
There is currently no area outlooked for severe weather on Memorial
Day, however that is likely related to days 4-8 outlooks requiring
at least a slight (level 2 of 5) risk, and a marginal (level 1 of 5)
risk may be added to the forecast issued tonight for Monday.
Widespread rain should depart to the east Monday night, although an
isolated thunderstorm is possible anywhere Tuesday afternoon, with
slightly higher chances south and east of Raleigh. A second cold
front is expected to pass over the region late Wednesday, but this
front should move through without any precipitation. High pressure
will then establish itself over the eastern United States for
Thursday and Friday.

Monday will be the warmest day out of the next seven, with highs
ranging from the mid 80s to the low 90s, with Sunday only a degree
or two cooler. Monday`s cold front should drop highs by about 5
degrees going into Tuesday, with highs falling another 3-5 degrees
on Wednesday and Thursday as well, with similar highs Thursday and
Friday. By the end of next week, highs should range from the mid 70s
to the low 80s. In addition, can`t rule out a couple of possible
cool spots dropping into the upper 40s Thursday night, with
widespread lows in the 50s.

&&

.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
-- Changed Discussion --
As of 150 AM Saturday...

Tricky aviation forecast for this morning through daybreak. Cirrus
over much of central NC has prevented prolonged fog development thus
far, but a thinning trend has been evident on satellite imagery over
the past couple hours with most locations calm at the surface.
Crossover temperatures at most terminals will likely be too low for
prevailing fog with the exception of RWI. Guidance continues to
favor RWI and the vicinity for IFR/LIFR fog this morning with the
06z TAFs leaning on climatology for timing of lowest restrictions.
Shallow fog/stratus will lift through 13z with isolated to scattered
afternoon/evening showers and storms yet again. Best chance for
organized convection will be near the Triad terminals (GSO/INT) with
airmass storms possible elsewhere.

Looking ahead: Primarily diurnally driven showers/storms will be
possible at all terminals through Mon, with the best chances Mon
aft/eve ahead of a cold front, which should move through the area
Mon night.
-- End Changed Discussion --

&&

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

&&

$$
SYNOPSIS...Green
NEAR TERM...Kren
SHORT TERM...Badgett
LONG TERM...Green
AVIATION...Swiggett/KC