231
FXUS61 KRNK 160545
AFDRNK

Area Forecast Discussion
National Weather Service Blacksburg VA
145 AM EDT Mon Sep 16 2024

.SYNOPSIS...
High pressure will continue to cover the Mid Atlantic region
through this evening, as a low develops off the Carolina coast.
This low will track through Virginia Tuesday and Wednesday,
bringing rain to much of the area. Low pressure nearby may keep
a few showers around into late week.

&&

.NEAR TERM /THROUGH TODAY/...
As of 725 PM EDT Sunday...

1. Dry, but breezy conditions continue through Monday morning.
2. Chances for rain increase over the Piedmont and Southside
Monday afternoon.

Modest adjustments made to cloud cover for this evening update,
as high level clouds continue to overspread the eastern portions
of the area ahead of the approaching Potential Tropical Cyclone
8, currently still off the coast of the Carolinas. A few light
showers have been observed across central NC and the far VA
Southside as the easterly winds north of the system and around
the edge of the high pressure wedge draw moisture into the area
from the Atlantic, but otherwise the area remains dry for most.

Previous discussion below...

As of 130 PM EDT Sunday...

High pressure centered over New England will maintain its hold over
the region through at least Monday morning, with its wedge of
dry air pushing southward into the area. Low stratus will slowly
erode this afternoon east of the Blue Ridge, but not
completely, and skies will continue to be partly to mostly
cloudy in the east, with persistent northeasterly winds. Drier
air to the west will keep skies clearer over southeast WV and
the Allegheny Highlands of VA through today. Breezy winds
continue today and through tomorrow, as the pressure gradient
tightens between the high pressure to the north of the area and
the developing low pressure off the coast of the Carolinas. High
clouds will increase over the area tonight and tomorrow, as
this low pressure system moves closer to the coast and
eventually inland. Rain from this system may reach the far
eastern counties of the forecast area as early as late Monday
morning, but more likely to be Monday evening. With the
increase in clouds, expecting high temperatures Monday to be a
few degrees cooler, in the low 70s. Lows will be in the low 50s
in the west and upper 50s to near 60 in the east.

&&

.SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
As of 153 PM EDT Sunday...

Key Messages:

1) A much needed rainfall for the area Monday night-Tuesday.

2) Some locally heavy rain may cause isolated flooding issues, but
dry conditions overall should prevent most from seeing water issues,
except typical ponding.

3) More scattered coverage Wednesday.

A look at the latest models still shows the GFS as a faster/westward
trend, with some of the high-res model camping in that area as well,
while the NAM/ECM and CMC are in the slower camp.

Despite this, models agree enough that bulk of rainfall is going to
stream in from the Atlantic into our area Monday night into Tuesday
before drifting northward into the mid-Atlantic Wednesday. Should
see most areas get measurable rainfall out of this, but still having
to hedge pops as there are still timing differences/track
differences. Appears along/east of the Blue Ridge could get 1-3
inches of rain with lesser amounts over WV during the Monday-Wed
period but most of that falls late Monday night into Tuesday.

This surface low stays non-tropical per latest NHC discussion but
should bring some gusty northeast/east winds in Monday night-
Tuesday. A few gusts over 30 mph likely in the higher ridges and
portions of the Piedmont before this low weakens Tue afternoon.
Could very well see some limbs/weaker trees fall down. The drought
has also brought stress on some trees/leaves and have some colors
and dying leaves in the mountains, which this wind may likely blow
off.

Beyond Tuesday the surface low occludes across central VA but as
upper low will be overhead, scattered showers/few storms are
expected mainly in the afternoon.

With clouds/rain and breezy conditions will likely see highs running
5 to 10 degrees below normal Tuesday with 60s in the mountains to
lower 70s piedmont. Lows stay near to above normal due to clouds
with lows in the mid to upper 50s in the west to lower 60s east.

Wednesday may see slightly warmer temps with a little more sunshine
with upper 60s to lower 70s mountains to mid to upper 70s east.

Forecast confidence is average on pops/qpf but above average on
temps/sky cover/winds.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
As of 1132 AM EDT Sunday...

Key Message:

1) Model disagreement leads to low confidence forecast especially in
terms of rain chances.

All models are in quite a big disagreement in the extended as to
where the upper low/trough will be and the upper ridge. With much
disagreement between models and their ensembles, leaned toward
persistence and the blend of models which keeps a daily chance
of showers, maybe a storm or two with some semblance of an upper
trough overhead or just east and a baroclinic zone along the
coast. Overall pattern favors low pops and mainly in the
afternoons, with clouds more at night and mix of clouds and
sunshine during the day. This will lead to highs closer to
normal or slightly below and at or above normal.

&&

.AVIATION /06Z MONDAY THROUGH FRIDAY/...
As of 140 AM EDT Monday...

Mostly VFR conditions across the area at this time, with a few
areas of MVFR ceilings along the higher elevations of the
southern Blue Ridge. Ceilings will gradually lower throughout
the day as Potential Tropical Cyclone Eight moves slowly towards
the Carolinas.

Generally east to northeast winds today and tonight. Winds
become gusty again this morning, gusts between 20 to 25 knots
are possible for KDAN and KLYH, as well as the along the Blue
Ridge. There may be too much cirrus for fog in the Greenbrier
Valley early this morning. Left a potential for a couple of
hours of MVFR fog in at KLWB.

Light rain from the tropical system reaches the VA and NC
Piedmont this afternoon but is more likely after 00Z/8PM.

Forecast confidence is average for ceiling, visibility, and
wind.

EXTENDED AVIATION OUTLOOK...

Periods of sub VFR conditions are possible through Thursday, as a
low pressure system brings rain and clouds to the area through the
midweek. Widespread rain continues into Tuesday A lower chance
of rain remains in the area through rest of the week.

&&

.EQUIPMENT...
As of 145 PM EDT Sunday...

The Lynchburg ASOS (LYH) is still experiencing data transmission
issues, mainly at night. Please use caution when using data
from this site, as some may be missing. Technicians continue to
investigate the problem. No estimated date for return to full
service at this time.

&&

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

&&

$$

SYNOPSIS...AMS/AS/WP
NEAR TERM...AS
SHORT TERM...PW/WP
LONG TERM...PW/WP
AVIATION...AMS/AS
EQUIPMENT...AS/SH