984
FXUS61 KRNK 161348
AFDRNK

Area Forecast Discussion
National Weather Service Blacksburg VA
948 AM EDT Thu May 16 2024

.SYNOPSIS...
A wavy boundary and lingering moisture will keep isolated
showers and thunderstorms in the forecast today before ending
this evening. Another storm system will cross the area
Saturday through late Sunday. This system will bring widespread
rain to the area. Monday and Tuesday look drier. High
temperatures generally look to be in the 60s and 70s, with a
slight cool off beginning Sunday.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 945 AM EDT Thursday...

Fog has diminished, but still have low clouds hanging around
this morning. Should see clouds thin a bit as the day goes, but
will not be a totally sunny day. Overall still expecting a
mostly dry day, but a few afternoon showers and perhaps an
isolated thunderstorm will be possible. Any rain/storms will be
weakening by sunset.


As of 230 AM EDT Thursday...

Key Messages:

1) Isolated showers this morning with lingering cloud cover
today...some clearing.

2. Chances for showers/isolated storms return briefly this
afternoon, and end after dark.

A trough of upper level low pressure and associated PVA will
continue to move off the East Coast this morning. A weak surface
trough was helping to keep a few areas of light rain over parts
of the Piedmont this morning. Elsewhere, stratus and fog as
well as a little drizzle were noted.

Stratus and fog will gradually lift later this morning, with
some clouds, especially over the mountains, hanging around a
good portion of the day. A wavy boundary approaching from the
north and breaks in cloud cover will keep a chance for showers
and thunderstorms in the forecast for this afternoon and
evening, with the higher chances over the mountains. East of the
Blue Ridge will have less of a chance due to weak NW flow, but
we may see some spillover. This activity will end after dark.
Instability will again be very limited so not expecting anything
strong...however moderate rain is possible.

Highs today will be limited by clouds, but rising heights and
breaks in cloud cover should get us into the mid 60s to mid 70s
for the mountains, and the mid 70s to near 80 for the Piedmont.
Tonight into Friday morning, expect more fog, some of it dense,
with lows in the 50s.

Confidence in the near term forecast is high.

&&

.SHORT TERM /FRIDAY THROUGH SUNDAY NIGHT/...
As of 200 AM EDT Thursday...

Key Messages:

1. Rain and thunderstorms late Friday and through the weekend.
2. Near normal temperatures, cooler over the weekend.

Friday will start off dry, with weak ridging aloft over the
southeast and high pressure overhead. An upper trough will
slowly track eastward from the central US into the Ohio and
Tennessee Valleys through the end of the work week, while a low
pressure deepens over the Gulf Coast states. South to
southeasterly flow at the surface behind a lifting warm front,
and southwesterly flow aloft ahead of the approaching trough
will advect warmer air and more moisture into the area, PWATs
forecast to reach 1.25" to 1.5", which is above the 90th
percentile relative to climatology, by late Friday. With ample
moisture in the atmosphere, there is the potential for heavy
rainfall Friday through Saturday, which raises some concerns for
localized flooding of urban areas and areas that have recent
rainfall already this week. The marginal risk of excessive
rainfall is mainly for the west on Friday, where the rain will
reach first, before expanding to the rest of the forecast area
for Saturday, as coverage of showers and possible storms becomes
more widespread.

Storm potential Friday will depend on how much surface heating
the area will receive through the day. Forecast SBCAPE values
are around 1000 J/kg by Friday afternoon, so enough to get some
scattered storms to develop, and with forecast shear between 30
to 40 knots, some multicell storms are possible. Saturday will
be similar, although showers through most of the day, and with
the upper trough just to the west of the area, may see more
widespread coverage of showers and storms. Coverage should start
to wane after Sunday morning, as the upper wave passes the
area, and surface low moves off the coast, though there is not
much agreement among models as to when the low finally departs.

Temperatures will be warmest on Friday, especially if there are
more breaks in the clouds. Saturday will be cooler with clouds
and rain, and Sunday looks be cooler as well, with winds
turning northeasterly, but also depending on when showers move
out of the area.

&&

.LONG TERM /MONDAY THROUGH WEDNESDAY/...
As of 230 AM EDT Thursday...

Key Messages:

1. Drier weather for first half of the week.
2. Warming temperatures, reaching above normal by midweek.

Following the weekend system, 500mb ridging starts to move back
into the area, and high pressure centered over the northeast
will wedge down the east side of the mountains. That being said,
the area may be cooler and hold on to clouds longer on Monday
than current guidance suggests, especially if there is still
ample moisture present, with the low sitting just off the VA/NC
coast. With models trending a bit slower with the passage of the
upper trough and surface low, still somewhat uncertain in how
long any rain showers will linger in the area, though confidence
is increasing that late Monday and Tuesday should be drier as
ridging builds overhead.

A broad 500mb trough will track eastward through the central US
through the midweek and will help to flatten the upper ridge
over the eastern US. The associated cold front looks to reach
the Midwest and Ohio Valley by Wednesday. Although towards the
end of the forecast period, with warming temperatures and
increasing dewpoints ahead of the front, will have to watch for
any storm potential.

Temperatures will be on a gradual warming trend through the
period, reaching near to just above normal by midweek.

&&

.AVIATION /14Z THURSDAY THROUGH MONDAY/...
As of 240 AM EDT Thursday...

A wavy boundary and lingering moisture will keep isolated
showers and thunderstorms in the forecast today before ending
this evening. IFR conditions will burn off/lift during the 14Z
to 18Z time frame, resulting in mostly overcast VFR conditions
by early afternoon. May see a few showers and storms develop
with late afternoon heating and a boundary nearing from the
north. SHRA/TSRA looks scattered again, but more likely for the
mountain terminals. Late tonight into Friday morning expect
another round of IFR to MVFR fog and stratus.


EXTENDED AVIATION OUTLOOK...

Friday: Deteriorating conditions. Flight restrictions possible
by afternoon due to low CIGs with an increasing coverage of
SHRA/TSRA.

Friday night and Saturday: Flight restrictions expected due to
low CIGs/VSBYs in SHRA/TSRA.

Sunday: Some restrictions possible, especially early, with a
decreasing coverage of SHRA/TSRA.

Monday: Mainly dry. Isolated SHRA/TSRA possible over the
mountains.

&&

.RNK WATCHES/WARNINGS/ADVISORIES...
VA...None.
NC...None.
WV...None.

&&

$$

SYNOPSIS...SH
NEAR TERM...BMG/SH
SHORT TERM...AS
LONG TERM...AS
AVIATION...SH