Scientific Forecaster Discussion
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Area forecast discussion
National Weather Service Blacksburg Virginia
913 am EST Wed Nov 13 2019
high pressure settles across the area today into Thursday. Low
pressure rides along the southeast coast Thursday night into
Friday, bringing some clouds and our next chance for
precipitation, mainly to the Piedmont areas. Temperatures will
moderate during the next few days.
Near term /through tonight/...
as of 913 am EST Wednesday...
With temperatures rising this morning wind chills have climb,
thus wind chill headlines were allow to expire. Morning low
clouds in the western mountains have eroded with the dry air.
This morning satellite loop showed some high clouds spill
southeast out of the Ohio Valley. High pressure will build
southeast into our area this afternoon into tonight. Made some
minor adjustments in temperatures for this morning utilizing the
latest surface obs, their trends and blended in nbm. Despite
sunshine, high temperatures will only climb into the upper 20s
in the mountains to the lower 40s in the Piedmont.
As of 245 am EST Wednesday...
Will leave headlines as is, with wind chills of zero to 10 below
across the higher mountains this morning.
Clouds lingering across the mountains this morning with Arctic air
wringing out isolated flurries. Will see the dry air erode the
clouds/flurries by mid morning with mainly sunny skies throughout
the day under strong high pressure, though some high clouds may
spill across the sky north of a Bluefield to Lynchburg line.
Despite sunshine, temperatures will stay well below normal with
light/variable winds. Slightly warmer than Tuesday afternoon, with
highs in the 30s in the mountains with upper 30s to lower 40s mainly
east of the Blue Ridge. Record cold high temperatures are reachable
at Danville and Roanoke. See climate section below for records.
High pressure works east this evening into overnight parking out
from the northeast to the central Carolinas. With a mainly clear sky
through most of the night and good radiational cooling conditions,
went close to the NAM and European model (ecmwf) MOS for lows. The only record low
based on the forecast that may get broken or close to will be
Danville. After midnight, southern stream energy moving across the
Gulf Coast states will start sending high clouds our way.
Forecast confidence: high, except medium on cloud cover late tonight.
Short term /Thursday through Saturday/...
as of 255 am EST Wednesday...
High pressure will drift offshore on Thursday, while a low pressure
system moves into the Gulf of Mexico. Although the morning should
begin dry, clouds will increase across the mid Atlantic by the
afternoon. Moisture streaming northward from this low pressure
system could reach Southside Virginia and the North Carolina
Piedmont by Thursday evening. This moisture will eventually set up a
chance of light rain east of the Blue Ridge during Thursday night.
While confidence remains moderate that the precipitation will stay
as cold rain, any westward shift of the moisture back toward the
crest of the Blue Ridge could result in a chance of light mixed
precipitation. The overall model consensus still remains fairly
consistent with the placement of the precipitation for now.
Once the low pressure system reaches Florida, it should track
northeastward toward the North Carolina coast on Friday and drift
further away from the shoreline by Friday night. Therefore, pops
have been shaped with slight chance to low chance of rain along and
east of a line from Yadkinville, NC to Lynchburg, Virginia during the same
timeframe. Models are depicting a second area of low pressure to
form just off the Georgia and South Carolina coastline on Saturday.
Eventually, chances of rain should trend downward across Southside
Virginia and the North Carolina Piedmont as skies should partially
clear by the afternoon, while northeast winds could pick up in the
Piedmont as the second low deepens.
Because of the thick cloud cover expected throughout this forecast
period, a smaller diurnal range in temperatures may occur than what
the model guidance is currently depicting. Thus, low temperatures
have been nudged a little upward, while highs have been bumped a
little downward. These adjustments may become more significant as
confidence increases with this cloudy and damp situation. Overall,
this pattern should provide temperatures that will run below normal
for the middle of November.
Long term /Saturday night through Tuesday/...
as of 232 PM EST Tuesday...
The system off the Carolina coast will become an occluded low, but
will stay off the coast through Sunday. Early next week, a cold
front tracking across the Ohio and Tennessee valleys will push
the coastal low further out to sea. However, this front will
have a new low pressure system with it, coming out of the Gulf
and along the East Coast next week. Unlike this weekend system,
the low with the front will move north very quickly.
Temperatures will remain slightly cooler than normal over the
weekend, then moderate towards normal through mid week.
Aviation /14z Wednesday through Sunday/...
as of 600 am EST Wednesday...
VFR through the taf period with high pressure in control. Winds
turn from light/variable to east/southeast late today into
tonight as the high moves east.
Forecast confidence high in all elements.
Extended aviation discussion...
VFR conditions continue into Thursday under high pressure.
Models showing potential southeast coastal system moving
moisture toward Dan Thu night- Fri which could bring ceilings
toward low end VFR. Otherwise VFR Saturday and Sunday.
as of 305 am EST Wednesday...
Only one record low broken Tuesday November 12th. High pressure
with a cold airmass will lead to some records falling today, for
lows and for coldest high temperatures. The high sets up over
the Piedmont tonight and we could see some record lows again
Thursday morning, but mainly at Danville.
Sitecoldest highs/year coldest lows/year
Bluefield 28/1976 10/1911
Danville 41/1968 20/2016
Lynchburg 36/1911 20/1996
Roanoke 38/1976 19/1920
Blacksburg 34/1968 15/1983
site record lows/year