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544
FXUS61 KRNK 190023
AFDRNK

Area Forecast Discussion
National Weather Service Blacksburg VA
823 PM EDT Sat May 18 2024

.SYNOPSIS...
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A stationary front has been the focus for scattered to numerous
showers and thunderstorms. This front will begin to move south
overnight...shower coverage decreasing. High pressure will bring
dry weather from Monday into most of Wednesday, before an
approaching cold front Thursday brings the next chance of
showers.
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&&

.NEAR TERM /THROUGH SUNDAY/...
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As of 800 PM EDT Saturday...

Key Message:

1) Showers/storms diminish this evening.

2) Drier tomorrow with only a slight chance of rain for the
mountains.


Shower/storms continue across the mountains...but weakening with
time as stable air arrives from the northeast. Stationary
boundary assisted by outflow from thunderstorms is getting a
nudge to the south, this front easily defined by e-w line of
storms bisecting the state of NC...south of I40. Trend is for
this activity to continue to move south and away from our CWA.
Showers/storms along the Appalachian divide are the result of
convergent northeast flow and daytime heating. This activity
should weaken with time but may not entirely go away per
lingering convergence. For now will maintain high chance pops
across the mountains until midnight...then cut numbers for the
late night. Still can`t rule out some poor drainage flooding...so
be on the lookout for ponding of water on roads.

Cool air wedge strengthens overnight and cooler air and low
clouds will cover a large portion of the area by tomorrow
morning. Expecting some fog development as well. May see some
erosion of the wedge throughout the day tomorrow. A chance of
some differential heating/orographic lift downpours or isolated
thunderstorms across the western mountains in the afternoon, but
otherwise most of the area should remain dry with the northeast
flow in place.
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&&

.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
As of 1215 PM EDT Saturday...

Key Messages:

1). Mainly Dry through the period for a change.

2). Temperatures near seasonal normal.

The weak and broad upper trough across the eastern U.S. will
lift out of the region Sunday allowing an upper ridge to build
eastward and northeastward into the region from the south
central U.S. Dynamics/forcing will be limited under the upper
ridge with warming temperatures aloft. At the surface, a
lingering wedge will remain across the area into Monday, but
gradually dissipate through the period. Increased sunshine, less
precipitation, and the dissipating wedge will allow
temperatures to warm back to seasonal levels compared to the
last few rather cool days. Other than a scattering of diurnally
driven showers across the western mountains, and principally the
southwest VA/northwest NC mountains, little if any
precipitation is expected through this time frame.

Temperatures will range mostly from the 50s at night to the 70s
mountains into the lower 80s elsewhere through the period.

/Confidence Levels in Forecast Parameters/
- Moderate to High Confidence in Temperatures,
- Moderate Confidence in Precipitation Probabilities,
- Moderate Confidence in Wind Direction and Speed.

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
As of 1215 PM EDT Saturday...

Key Messages:

1). Increasingly unsettled weather pattern evolves during the
later half of the week.

2). Temperatures remain near seasonal normals.

Upper ridging across the eastern U.S. will gradually break down
through the later half of the week as a strong short wave tracks
from the Midwest toward the Great Lakes. An associated cold
front will move slowly into the region Thu-Fri. Shower and
thunderstorm chances will increase as the front approaches from
the west, especially along and west of the Blue Ridge. Timing is
a bit uncertain as the ECMWF is quite a bit slower than the GFS.
The ECMWF would delay the bulk of the precipitation until Friday
going into the weekend. Activity looks to be somewhat scattered
and mostly diurnal at this point with a low severe threat. Heavy
rain may eventually be a greater concern, but too far out to
hone in on any specific threats.

Temperatures are expected to remain relatively near seasonal
normals with a slight cooling trend from midweek to the weekend
as clouds and precipitation coverage increase. Look for lows
mostly in the 50s to lower 60s urban areas with high
temperatures primarily in the 70s mountains with lower 80s
Piedmont.

/Confidence Levels in Forecast Parameters/
- Moderate Confidence in Temperatures,
- Moderate Confidence in Precipitation Probabilities,
- Moderate Confidence in Wind Direction and Speed.

&&

.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
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As of 800 PM EDT Saturday...

Lingering showers and storms expected until midnight across the
mountains. This may impact BLF/LWB/BCB. East of the mountains a
layer of stratus is expected to develop with cigs lowering to
IFR/LIFR for the overnight. Fog may also restrict visibility,
but confidence low as to whether dense fog will become a problem
due to all the low level cloud cover. Pattern recognition
suggests low cig will be the bigger hazard...the low cloud base
obscuring the ridges tonight and early Sunday morning.

Cool northeast flow over the Piedmont of Virginia will continue
to supply OVC to BKN cigs of 005 to 015 through early Sunday
afternoon before improving.

EXTENDED AVIATION OUTLOOK...

A few showers or isolated storms in the mountains on Sunday
afternoon. MVFR/IFR clouds and showers remain in the area
through Sunday night.

Gradual improvement expected Monday, although northeast wind off
the Atlantic is still supportive of low level cloudiness east of
the mountains. A better opportunity for VFR is expected Tuesday
into Wednesday.
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&&

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

&&

$$

SYNOPSIS...BMG/PM
NEAR TERM...BMG/PM
SHORT TERM...RAB
LONG TERM...RAB
AVIATION...PM