Forecast Discussions mentioning any of
"ACARS" "MDCRS" "AIRCRAFT" "TAMDAR" "AMDAR" "WVSS" received at GSD on 03/17/20
Area Forecast Discussion
National Weather Service Blacksburg VA
1015 PM EDT Mon Mar 16 2020
High pressure over northern New England will maintain a damp
and cool northeast flow until early Tuesday before the first in a
series of upper-level disturbances tracks into the Ohio and
Tennessee valleys, keeping the weather unsettled through much
of the week ahead. Temperatures will be moderating to well above
normal by late week.
.NEAR TERM /THROUGH TUESDAY/...
As of 1015 PM EDT Monday...
No change to previous thinking as the wedge will persist through
tonight. Have sculpted POPs a bit to match current and expected
radar trends, but the flavor of the forecast remains the same
with the best chance of showers for locations west of the Blue
Cold air damming from the New England surface high will persist
until around mid-day Tuesday with low clouds and fairly cool
temps, although not much diurnal fluctuation. Lows tonight upper
30s NW to mid-40s SE. Wedge starts to weaken Tuesday with some
breaks in overcast, mainly across the piedmont and temperatures
rebounding sharply where the sun does appear. Fairly wide spread
in guidance for highs tomorrow but went toward higher end with
mid-60s in the piedmont and mid/upper 50s in the mountains.
Just as the wedge weakens tomorrow, cloudiness from an
approaching weak short- wave over the Tennessee Valley will
bring more low clouds and increased chances for rain with the
highest pops across our southwest counties. Like many recent
systems, this one looks `prepped` to deliver the best QPF to the
far western counties with up to around 0.25 inches by evening,
but with considerably less across the central mountains and
piedmont where very little is expected in this time frame.
.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY NIGHT/...
As of 230 PM EDT
With high pressure starting to wedge back into the area Tuesday
night into Wednesday, looking for temperatures on Wednesday to
struggle to warm. Meanwhile, we will be tracking a low pressure
system that will track across the Great Lakes/Ohio Valley that will
bring in the chances for showers mainly for Wednesday evening/night.
Moisture with this system will be limited, with most of the rainfall
occuring north of I-64.
Looking ahead to Thursday and Friday, the most notable part of the
forecast will be the warming trend. Guidance remains on track for
areas east like Danville to warm to 80 degrees, along with most in
the west warming into the 70s. We can thank some stout SW flow for
that. As to be expected, nighttime lows will also be above average
with the warm. A weak wave and then a front will provide the
opportunity for rainfall both days. With both days also comes some
instability with CAPE values 100-300j/kg, don`t be surprised to see
at least a few isolated storms. I think Thursday will have the
greatest chance for them with the most abundant spread in
instability, as well as some shear to work with.
.LONG TERM /FRIDAY THROUGH MONDAY/...
As of 230 PM EDT Monday...
After Friday`s system pushes to our south early Saturday, the
weekend trends toward mostly dry, though cloud coverage comes into
question thanks to that front not making it very far to our south.
High pressure builds in, but doesn`t remain settled as it quickly
pushes off the coast by Sunday. This makes way for our next system
that will start to move in late Sunday into Monday.
Thanks to the front that does pass through for the start of the
weekend, temperatures make a sudden downward trend and turn back to
a more average range, though Saturday night will be chilly with
areas in the west dropping to the mid 20s.
.AVIATION /02Z TUESDAY THROUGH SATURDAY/...
As of 815 PM EDT Monday...
Expect some variability in flight conditions all sites as the
lingering wedge gets challenged by a weak wave approaching from
the west. Believe locations east of the Blue Ridge will maintain
VFR for most of the night with MVFR conditions most likely for a
period early Tuesday morning. Locations west of the Ridge will
see early VFR conditions trend down after Midnight with MVFR/IFR
conditions becoming established late tonight.
As the wave pulls away and high pressure starts to build in
Tuesday afternoon expect some improvement west of the Ridge toward
the end of the valid period, but KBLF looks to remain in cloud
with persistent IFR through the end of the valid period.
Winds will generally be light with litte impact to aircraft
.Extended Aviation Discussion...
The pattern of quick moving arriving and exiting systems
continues this week with a strong zonal flow aloft across the
U.S. Several chances for rain and poor flying conditions will
occur this week but the main effect will be intermittent