Area Forecast Discussion
Issued by NWS Blacksburg, VA-- Highlight Changed Discussion --
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FXUS61 KRNK 221744
Area Forecast Discussion
National Weather Service Blacksburg VA
144 PM EDT SUN MAY 22 2016
A series of low pressure systems will lift northeast off the mid
Atlantic and New England coasts through Tuesday as higher
pressure builds slowly east from out of the Mississippi Valley.
.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --As of 120 PM EDT Sunday...
Forecast on track though made some adjustments to temps as they
were running warmer in most areas, especially Roanoke. Still
overall looking at showers and isolated thunderstorms across
Southeast WV, east and southeast toward the Piedmont of VA into
portions of NC, with less coverage across the foothills of NC into
the High Country.
Previous valid discussion...
Several spokes of short wave energy rounding base of upper trof
over the central and northern Appalachians will help to amplify
upper flow and support development of vertically stacked H7-H5 low
pressure that will drift south from out of upstate NY into eastern
VA by this evening - then drift east to the coast by daybreak
Shower threat continuing until at least mid- to late evening
until thermodynamic support wanes.
Cool air advection and cloud cover in most areas should help to
keep daytime highs lower than those experienced on Saturday -
mainly mid 50s across the highest elevations, to around 70 across
southside VA into north central NC. Overnight lows should be
fairly uniform across the area - mainly mid to upper 40s in the
mountains, to the lower 50s across the Piedmont.
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.SHORT TERM /MONDAY THROUGH WEDNESDAY/...
As of 320 PM EDT Saturday...
The blocky upper pattern which has been prominent for the past several
days will slowly be transitioning through the first part of next week.
The closed upper low and associated cold pool aloft over the mid
Atlantic region will be replaced by a broad low amplitude upper ridge
and a Bermuda high at the surface by the middle of the week. This will
bring a gradual improvement in our weather along with a significant
The influence of the upper low combined with diurnal instability will
still be great enough to keep a good chance of showers across most of
the region on Monday. By Tuesday as the ridging begins we will be down
to just a slight chance of showers across the eastern portion of the
area. However as the evolution of the pattern begins to pump steadily
warmer and more moist air into the region the chances for showers and
thunderstorms will start to increase again by Wednesday afternoon.
We will start the week with very cool conditions as temperatures remain
5 to 10 degrees below normal with highs in the lower 70s east of the
Blue Ridge and in the low to mid 60s to the west. However by Wednesday
we will be getting a taste of summer with highs in the middle 80s east
of the Ridge and in the mid 70s/around 80 to the west.
.LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/...
AS OF 1211 PM EDT Sunday...
Expect warmer...more like mid to late June type temperatures and
weather from midweek into the holiday weekend as an upper ridge
builds over the Southeast U.S. This pattern will favor mainly dry
yet more humid conditions. There will be enough instability and
moisture each day across the Appalachians to generate scattered
showers and thunderstorm, with less threat in the Piedmont. The
cycle will be typical diurnal afternoon/evening variety.
Highs Thu-Sun will range from the upper 70s to lower 80s in the
mountains to mid to upper 80s in the piedmont.
Lows will generally run from the upper 50s to lower 60s mountains to
mid 60s piedmont.
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
-- Changed Discussion --As of 135 PM EDT Sunday...
Aviation concerns will be centered on scattered showers and a few
thunderstorms from the Lewisburg vicinity east and southeast
toward Danville. Overall best threat for predominant showers will
be Lewisburg and perhaps Lynchburg. Otherwise will see a broken
deck of CU/SC with isolated CBs in the 3-6kft range. Northwest to
North winds will be gusty at times, particularly over Roanoke to
Bluefield. These winds will be subsiding after 00z this evening.
Scattered showers expected to wane, and eventually end over the
entire terminal forecast area tonight following loss of daytime
heating. However, some isolated lingering showers/sprinkles may
occur until after midnight along and east of a KLYH-KDAN line
which will remain closer to an upper level low pressure system
near the coast. Models favor some lowering of broken cigs to
around 1-3kft with some MVFR fog. Confidence just high enough to
at least go MVFR at most sites.
Will see continuation of mainly broken ceilings Monday though
should rise to VFR by late morning. Showers and isolated storms
again possible moreso east of Danville to Lynchburg line, though
some may slip toward the mountains in the afternoon but coverage
will be more isolated.
Overall looking at improving aviation weather after the upper low
lifts out Monday night into Tuesday. We will be going to a more
summer like pattern mid to late week. Overall, VFR expected but
watch for early morning fog at times around LWB/BCB. Also some
convection could pop up in the mountains Thu-Fri.
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