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Area forecast discussion 
National Weather Service Blacksburg Virginia
753 PM EDT Fri Oct 21 2016

strong cold front is just off the Virginia coast early this
evening with tight pressure gradient situated between low pressure
just southeast of Long Island, and high pressure over the Midwest.
This high will move southeast Saturday and Sunday. A weak cold
front will cross through the mid Atlantic region on Monday.


Near term /through Saturday/...
as of 735 PM EDT Wednesday...

Tight pressure gradient creating brisk/breezy to windy conditions
this evening. However, the 00z rnk sounding coming in denotes
30-35kt 8h jet. This is about 10 kts less than latest model
depictions, and area obs are showing majority of wind gusts below
advisory levels. The pressure rises are not that impressive but
will still see some good low level winds at least into early
overnight. At this time no changes to the Wind Advisory, but not
as confident that most will see gusts higher than 30-35 mph...Wind
Advisory being gusts over 45 mph. The windiest places will be
higher elevations of the NC mountains to the Grayson Highlands and
Blue Ridge, as well as the alleghanys, generally above 3000 ft.

Otherwise, looking at the showers over southeast WV into portions
of SW Virginia. Hrrr showing this activity weakening and being
more confined to the western slopes of southeast WV overnight so cutting
pops back some. Temperatures had plummeted to the mid to upper 30s
across some of the higher elevations above 4000 ft in NC and VA,
with most of the west mainly in the mid 40s to around 50, and in
the upper 50s east. Not seeing threat of a freeze warning, except
above 4000 ft like beech mtn NC and Mt Rogers where lows could
dip into the upper 20s. The rest of the mountains will be in the
mid to upper 30s but way too much wind and cloud cover for any

Previous valid discussion...

Western upslope areas will be gradually clearing out Saturday
morning, which will limit heating. Again, mav numbers looked


Short term /Saturday night through Monday night/...
as of 330 PM EDT Friday...

The low amplitude upper pattern is not very progressive as the closed
low over New England slides up into eastern Canada and keeps a broad
trof over the northeast as a ridge develops over The Rockies. Aside
from some lingering clouds west of the Blue Ridge Saturday night, this
pattern will keep fair weather with breezy conditions in the tight
pressure gradient between high pressure over the southeast and low
pressure under the closed low through Sunday.

A surge of short wave energy will spill over the ridge and push a weak
low from the Great Lakes region late Sunday to off the mid Atlantic
coast by Monday morning. This will initiate another round of strong
gusty winds Sunday night and send a plume of low level moisture into
the region from the northwest. This will result in a good amount of
clouds west of the Blue Ridge and maybe some upslope rain showers for
the western slopes late Sunday night into Monday.

With surface high pressure over the southeast giving US west to
southwest winds, warmer temperatures will start making their way into
the region and highs on Sunday will be seasonably in the 60s, a bit
cooler on Monday west of the Blue Ridge as cooler air starts filtering


Long term /Tuesday through Friday/...
as of 330 PM EDT Friday...

High pressure will move in from the upper Midwest and bring fair
weather with slightly below normal temperatures to the region for
Tuesday and Wednesday. The high will then take up a wedge position east
of the Appalachians as a vigorous short wave amplifies and drops out of
the upper Midwest. This looks to bring a chance of precipitation back
to our forecast for Thursday with some additional upslope precipitation
west of the Blue Ridge lingering into Friday.

Temperatures will generally be near seasonal norms through the


Aviation /00z Saturday through Wednesday/...
as of 750 PM EDT Friday...

MVFR or lower expected in the mountains with IFR or worse at blf
with upslope flow continuing into Saturday morning. The showers at
blf will be diminishing by midnight. Appears VFR sct/bkn at roa
and lyh overnight then clearing Saturday. Will see winds staying
gusty at all sites through Saturday with highest gusts around 30
kts possible at roa/bcb overnight.

The lower clouds will lift Saturday but expect at least a broken
ceiling of 3-5kft clouds at blf/lwb through most of the day, maybe
scattering at lwb after 20z.

Extended aviation discussion...

Saturday night through Monday...widespread VFR. No flight
restrictions. High pressure building in over the Tennessee Valley
then southeast United States will result in lighter wind speeds.

Tuesday and Wednesday...potential for River Valley fog in the
mountain valleys with local vsby restrictions between 08-14z each
morning, otherwise widespread VFR.


Rnk watches/warnings/advisories...
Virginia...Wind Advisory until noon EDT Saturday for vaz009-012>020-
NC...Wind Advisory until noon EDT Saturday for ncz001-002-018.


Synopsis...air mass
near term...ams/wp
short term...mbs
long term...mbs

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