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000
FXUS61 KRNK 200550
AFDRNK

Area Forecast Discussion
National Weather Service Blacksburg VA
150 AM EDT Wed Sep 20 2017

.SYNOPSIS...
A weak shortwave will move east across our region tonight into
Wednesday. Jose will track north, off the east coast tonight, before
sliding just east of New England today.

&&

.NEAR TERM /THROUGH TODAY/...
As of 700 PM Tuesday...

Afternoon and evening shower coverage remained extremely
isolated to the higher elevations Tuesday, with a weakening
trend expected to continue after sunset. Upstream shower
activity continues to stay well west of the forecast area
thanks to a stubborn layer of dry air in the mid levels, with
only decaying cloud debris noted spreading east into the
Appalachians by nightfall.

Previously Valid Discussion...
High pressure will remain across our area this afternoon into
tonight. Our forecast area will remain under dry air aloft
between Hurricane Jose passing well offshore and the next
upstream axis of deeper moisture associated with a cluster of
mid level shortwave energy in the Midwest.

A weak surface cold front to the northwest slowly edging east
towards the mountains late tonight. Low level moisture and light
winds will result in patches of fog especially in the valleys.
Low temperatures tonight will range from the the mid 50s in the
mountains to the mid 60s in the piedmont.

Wednesday will feature another warm afternoon with high temperatures
from around 70 degrees in the northwest mountains to the mid
80s in the Piedmont. Shortwave will slide east across the area
and be enhanced by diurnal heating. The cap will weaken enough
to allow for isolated to scattered showers and thunderstorms
along and west of the Blue Ridge mountains.

&&

.SHORT TERM /TONIGHT THROUGH FRIDAY NIGHT/...
As of 248 PM EDT Tuesday...

A rather quiet weather pattern with little change in the low
level/upper level features. Will be relying on daytime heating and
weak upper impulses, along with some weak low level convergence for
isolated to scattered showers/storms Thursday-Friday afternoons.

Will seem more like summer like pattern though not as hot, but temps
will still run 3 to 10 degrees above normal.

Lows will run from the mid to upper 50s mountains, to lower to mid
60s foothills/piedmont and Roanoke.

Highs mainly upper 70s/around 80 west, with mid 80s east.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
As of 130 PM EDT Tuesday...

Surface and upper ridge will be sandwiched between tropical systems
off the east coast and strong upper trough over the central/western
U.S. this period. Will see how Hurricane Maria evolves and tracks
northward off the east coast next week, depending on how Jose
moves/weakens and if the upper ridge pushes further off the mid-
Atlantic coast.

At present, models in decent agreement keeping us on the warm and
dry side. Highs and lows will continue to range about 3 to 8 degrees
above normal.

&&

.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
As of 145 AM EDT Wednesday...

Mainly VFR East of the Blue Ridge tonight, with IFR VSBYs
possible at LWB/BCB just before sunrise. MVFR to brief IFR fog
possible at BLF. Mid level clouds over the mountains may delay
or inhibit fog formation. High confidence of MVFR fog in the
favored valleys by 10Z/6AM.

A weak short wave will be reaching the central Appalachians in
the morning which would result in more cloud cover and scattered
showers over the mountains. Low confidence on the probability of
any thunderstorms. Any chance would be after 16Z/noon with KBLF
the most likely airport to be impacted. Brief dips to MVFR
ceilings in the localized downpours will not be out of the
question with the showers.

Extended Aviation Discussion...

Overall persistence forecast to prevail for the rest of the
upcoming week into the weekend with strengthening high pressure
remaining in place between exiting Jose offshore and a weak
cold front approaching from the west. This should maintain good
flying weather outside of early morning fog/stratus through late
next week, with only isolated to scattered diurnal showers
possible Thursday afternoon as upper level energy slides
across. Dry weather is expected Friday through Sunday.

&&

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

&&

$$
SYNOPSIS...JH/KK
NEAR TERM...JM/KK
SHORT TERM...WP
LONG TERM...WP
AVIATION...AMS/JM