831
FXUS61 KRNK 240618
AFDRNK

Area Forecast Discussion
National Weather Service Blacksburg VA
218 AM EDT Sun Aug 24 2025

.SYNOPSIS...
Scattered showers and thunderstorms are possible through this
evening as a frontal system crosses the Mid Atlantic region.
After this system exits early Monday morning, high pressure
will return to bring cooler and drier weather for the rest of
the work week.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 200 AM EDT Sunday...

Key Messages:

1) Scattered hit and miss showers and embedded storms through
this evening.

2) Cooler temperatures and fog again Monday morning.

An upper level trough was situated in eastern Ontario Province
this morning. A significant short wave axis was swinging
around this trough and over the Great Lakes. This will help push
a pre-frontal trough and eventually a cold front into the Mid
Atlantic region today and overnight tonight.

The pre-frontal trough will be the main driver for scattered
showers and storms today. With weak wind fields aloft, expect
spotty coverage for the mountains, with a better area of
precipitation developing this afternoon in the foothills and
Piedmont as the pre-frontal trough moves southeast. We will see
marginal instability along the boundary as it crosses today,
with shear around 20 to 30 kts contributing to multicells.
Developing and prevailing westerly winds just off the surface
will limit precipitation and storm strength, so severe weather
is unlikely. Rainfall totals will generally range from a few
hundredths to a quarter of an inch, with the area from
Waynesboro to Boone`s Mill to Mount Airy seeing some higher
amounts...perhaps a half inch to an inch if we are lucky. Many
locations may miss out though.

Temperatures today will be in the 70s to low 80s once again. The
actual cold front will push through overnight tonight with
little fanfare. Drier and cooler air arrives behind it, dropping
the mountains into the 50s, with 60s for the foothills and
Piedmont. Expect lingering low-level moisture to trigger fog in
river and mountain valleys early Monday morning as skies clear.
Some stratus will be possible for the western mountains as
well.

Confidence in the near term is moderate.

&&

.SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/...
As of 130 AM EDT Sunday...

Key Points:

1. No precipitation.
2. Temperatures averaging five to ten degrees below normal.

A look at the 23 Aug 00Z NCEP Ensemble Mean 500mb Geopotential
Heights shows for Monday/Monday night a longwave trough that
extends from northern Quebec south into the Tennessee Valley.
Broad ridging exists over western CONUS. For Tuesday/Tuesday
night, the axis of the longwave trough shifts ever so slightly
east. Ridging continues across western CONUS. For
Wednesday/Wednesday night, the axis of the longwave trough
shifts to over New England south to along the VA/NC coast by
Wednesday evening. A shortwave trough within the longerwave
pattern might be over the Upper Mississippi Valley and the
western Great Lakes region. Ridging continues over western
CONUS.

At the surface, for Monday/Monday night a cold front will be
moving southeast of the region with high pressure advancing
from the west. For Tuesday/Tuesday night, the center of the high
shift southeast and will be centered near IA/IL. The expanse of
the high will cover much of central and eastern CONUS. For
Wednesday/Wednesday night, the center of the high shifts to over
the Lower Ohio Valley.

A look at the 23 Aug 12Z NAEFS Ensemble Situational Awareness
data shows 850mb temperatures for Monday are expected to range
from roughly +11C to +13C, nw-se across the area. The low end
of this range falls within the 2.5 to 10 percentile of the
30-year CFSR climatology. On Tuesday, values dip to +10C to +12C
with the low end of this range within the 1 to 2.5 percentile
the remainder of the region within the 2.5 to 10 percentile of
the 30-year climatology. For Wednesday, values are expected to
be within a +10C to +11C, n-s, range across the region, or the
2.5 to 10 percentile of the 30-year climatology.

The above weather patterns offers the following forecast. High
pressure will provide for no precipitation and temperatures
averaging five to ten degrees below normal.

Confidence in the above weather scenario is high.

&&

.LONG TERM /THURSDAY THROUGH SATURDAY/...
As of 130 AM EDT Sunday...

Key Points:

1. Temperatures trend slightly milder each day, but will still
be below normal for this time of year.
2. Vast majority of the region remains dry through the period.
3. Isolated showers/storms the afternoon of Friday/Saturday for
the NC mountains and neighboring sections of SW VA.

A look a the 23 Aug 00Z NCEP Ensemble Mean 500mb Geopotential
Heights shows for Thursday/Thursday night a longwave trough
still over the eastern US. Troughiness deepens off the coast of
the Pacific Northwest. The ridge axis over western CONUS is
expected to shift east to over the Rockies of US/Canada. For
Friday through Saturday night, little change is expected in the
overall synoptic pattern over North America as compared to
Thursday. For Saturday, longwave troughiness continues over
eastern CONUS. The trough off the Pacific coast is expected to
amplify. Ridging continues over the Rockies.

At the surface, for Thursday/Thursday night, the center of an
are of high pressure will pass over our region and be along
the Atlantic coast by Thursday evening. For Friday/Friday night,
the center of the high continues progressing northeast, but
with an associated ridge axis extending southwest over much of
eastern CONUS. For Saturday, little change is expected for the
location and orientation of the ridge axis.

A look at the 23 Aug 12Z NAEFS Ensemble Situational Awareness
data shows 850mb temperatures on Thursday around +12C across
the area. For southern sections of the region, this value falls
within the 2.5 to 10 percentile of the 30-year CFSR climatology.
For Friday, values inch higher to around +13C across the
region. Similar values are expected Saturday.

The above weather patterns offers the following forecast. High
pressure will continue to provide for dry conditions on Thursday
for the entire region. For Friday and Saturday, the center of
the high pressure will be to our east. Anti-cyclonic flow around
it may advect enough moisture into the area for the development
of some afternoon isolated showers/storms across the mountains
of NC and neighboring sections of SW VA. Otherwise, no
precipitation is still expected for the vast majority of the
region. While temperatures are still expected to remain below
normal, values will be trending slightly higher each day.

Confidence in the above weather scenario is moderate to high
with the biggest question mark being development of
showers/storms Friday/Saturday across the NC mountains.

&&

.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
As of 215 AM EDT Sunday...

Mostly VFR conditions are still in place this morning, but IFR
to LIFR ceilings and visibilities are likely for BLF, LWB, and
BCB starting in the next couple of hours and lasting through
about 14Z this morning. Increasing moisture and the arrival of
a frontal system will bring MVFR conditions in scattered showers
and storms to the area this morning through this evening. Some
rain will be moderate, but most of it will be light.

Expect -SHRA/-TSRA for the mountains this morning, ending by
18Z at BLF and LWB, before additional convection fires along the
Blue Ridge and shifts southeast this afternoon and evening.
Developing westerly winds at the surface and aloft will serve to
limit -SHRA/-TSRA and quickly end precipitation once a pre-
frontal trough each terminal. A cold front arrives overnight
tonight exiting the area Monday morning, but not expecting
precip along this. Fog and stratus are likely at times through
15Z Monday.

As mentioned, light southerly winds this morning will switch to
westerly and slightly gusty later today. Some patchy fog and
stratus lingers Monday morning for the mountains and river
valleys.


.EXTENDED AVIATION OUTLOOK...

NW winds behind today`s system will gust to 15-20 knots at
times through Tuesday. High pressure will support VFR conditions
through late next week. Winds remain NW to N through Wednesday
night before turning WSW Thursday.

&&

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

&&

$$

SYNOPSIS...SH
NEAR TERM...SH
SHORT TERM...DS
LONG TERM...DS
AVIATION...SH