Area Forecast Discussion
Issued by NWS Blacksburg, VA-- Highlight Changed Discussion --
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FXUS61 KRNK 230552
Area Forecast Discussion
National Weather Service Blacksburg VA
152 AM EDT MON MAY 23 2016
Upper low over the area will finally head offshore by Monday
evening, before lifting north toward the New England coast
Tuesday. As this occurs, high pressure builds in and temperatures
will start to rise back to at or above seasonal levels by mid to
.NEAR TERM /THROUGH TODAY/...
As of 905 PM EDT Sunday...
Last cluster of deep convection has pushed to the south of the
area during the past hour with just some remaining residual
showers mainly over the west with the vort axis along the western
side of the upper low. Expect these to gradually fade given loss
of heating but still enough faint surface based instability to
keep some low pops in through about midnight far west/sw.
Elsewhere given worked over nature to most areas along the Blue
Ridge and across the southeast per the exiting meso low, expecting
a few hours of little rainfall. However the core of the upper low
now over northern VA will sink south reaching the Outer Banks
early Monday. Latest short term guidance shows current light
showers rotating around this feature pivoting back southwest
after midnight. This will likely cause showers to return to parts
of the area mainly east of the Blue Ridge into Monday morning.
Thus trimmed back pops for a few hours through late this evening
before ramping up to low likelys LYH vicinity, and points east
late, with slight/chance coverage back to the Blue Ridge.
Otherwise mainly cloudy and continued cool with some locations
already near forecast lows due to cooling from earlier showers.
This still supports lows mostly in the upper 40s to mid 50s.
Previous discussion as of 300 PM EDT Sunday...
Expect showers and isolated thunderstorms to continue from Southwest
VA/SE West Virginia, east to the Piedmont thru evening, with storms
dying off after dusk. High-res models favoring two corridors now for
best coverage...albeit still mainly scattered. One over the far SW
VA mountains and the other still from the Alleghanys to Southside
VA. There may be a lull in activity overnight between shortwaves,
but another stronger wave moving in from KY into SC overnight
combined with the upper low over NC will keep threat going thru
Monday morning...but looks like the piedmont has better threat.
Lows tonight will range from the mid to upper 40s west to lower 50s
Monday, the upper low slowly moves off the NC/VA coast by will
continue to see shortwaves rotate in from the north on the west side
of this system. Still looks at least a scattered coverage of mainly
showers over most of the forecast area by midday into the afternoon.
With more clouds than sun across the area look for highs to be
similar to today from the mid to upper 60s west to upper 60s to
lower 70s east.
.SHORT TERM /TONIGHT THROUGH WEDNESDAY/...
As of 306 pm EDT Sunday...
A pattern change is coming finally for those who have not enjoyed
the cooler weather. As the upper low pulls away to the north toward
the New England coast Tuesday, upper heights will rise with surface
high pressure building overhead. Lingering showers over the
northeast CWA will diminish Monday evening. Skies clear but temps
will only fall into the upper 40s to lower 50s.
Tuesday will start the warmup but highs will be close to normal for
late May ranging from the lower to mid 70s west to upper 70s to
around 80 east under mainly sunny skies.
Dewpoints to start edging up into the 50s Tuesday night into
Wednesday as the high moves to off the Southeast coast, but staying
strong enough to keep skies clear to partly cloudy. Somewhat
westerly flow Wednesday allow temps to soar into the mid 80s east of
the Blue Ridge, with upper 70s to around 80 in the mountains. Models
are keeping the main storm track over the middle of the country,
though as we start to heat up cannot rule out a stray shower in the
afternoon over the higher terrain.
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
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 /06Z MONDAY THROUGH FRIDAY/...
-- Changed Discussion --As of 150 AM EDT Monday...
Southwestward moving bands of light showers/sprinkles on western
periphery of upper low pressure over eastern VA will continue to
threaten mainly Piedmont areas overnight, but with ceilings and
visibilities mainly remaining in the VFR range.
Further west and more removed from upper low, some clearing over
a moist ground combining with light winds has supported the
development of some patchy fog across portions of SW VA into SE WV
- with KBLF and KMKJ already down into the LIFR range. Threat for
IFR to LIFR restrictions should continue for the rest of the night
in this area, perhaps also impacting areas as far north as KLWB
until onset of daytime heating - with return to mainly VFR weather
expected by mid morning as fog lifts/mixes out.
However, onset of daytime heating will again help to reignite
widely scattered to scattered shower/thunderstorm development by
early- mid afternoon as proximity to upper low to east and
associated cool pool provide sufficient instability for vertical
development - similar to that experienced on Sunday, although
perhaps a bit less robust in nature. As a result, have included
VCTS in all terminal forecast sites for afternoon period - with
threat ending by early evening with loss of daytime heating and as
upper low finally begins to drift further east and away from area.
Overall expecting 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 with high pressure offshore
providing south to southwest flow. Thus, mainly VFR weather expected.
However, the potential exists for late night/early morning fog at
times around KLWB/KBCB and in some of the deeper mountain valleys.
Also some convection could pop up in the mountains Thursday-
Friday, making for localized afternoon/evening MVFR restrictions.
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