Scientific Forecaster Discussion
fxus61 krnk 181948
Area forecast discussion
National Weather Service Blacksburg Virginia
248 PM EST Thu Jan 18 2018
high pressure shifts from the Gulf Coast states this evening to
the southeast coast by Saturday. This will linger over the
southeast states into Monday before a cold front enters from
the west Monday night into Tuesday.
Near term /through Friday/...
as of 210 PM EDT Thursday...
Winter Weather Advisory for refreeze of snowmelt in NC through
Friday morning, per policy agreement with NC EM officials. Rest of
County Warning Area will likely be under a Special Weather Statement to cover
Otherwise, looking at high pressure building in with winds subsiding
this evening but not quite going calm. Still a chilly night with
lows in the teens, but at least wind chills will not be as low given
less wind. One possible concern tonight besides the slick roads
would be fog. With warm advection and somewhat lighter winds over
snow, fog can sometimes form. However, given limited melting the low
levels stay a little dry and winds may stay up enough overall to
restrict fog formation, but still possible, especially in the
We continue to stay in a split flow pattern into Friday with heights
rising and 8h temps rising per warm advection. Under sunny skies,
temperatures should reach into the 40s. We should start to see
better snowmelt Friday.
Short term /Friday night through Sunday/...
as of 115 PM EST Thursday...
This period of the forecast will be highlighted by a warming trend
across the area. An upper level ridge will build across the
southeast U.S., All while the synoptic flow across our region turns
zonal. By the end of this time period, low level trajectories that
clip far western parts of the area will have their origin from
across the western Gulf of Mexico. The result will be moderating
temperatures with eventually increasing clouds by the end of the
weekend, especially across the west, with also the potential for
some isolated showers across the far west by Sunday. By Sunday, high
temperatures will range from the low to mid 50s across the
mountains, and mid 50s to around 60 across the Piedmont.
Long term /Sunday night through Thursday/...
as of 130 PM EST Thursday...
The mild weather will continue Sunday night into Monday in advance
of an approaching cold front. Also, isolated to scattered showers
will start to increase across the area during the day in advance of
this same front. Look for showers to become more numerous Monday
night into early Tuesday morning as the front passes through the
region. While temperatures will decrease behind the front, readings
will still remain above normal for this time of year heading through
the middle part of the week.
After Monday night, our next chance for precipitation will be a
small one Wednesday night into Thursday as a weak disturbance passes
through FL/GA/SC. Otherwise, dry weather is expected as another area
of high pressure builds into the region.
Aviation /20z Thursday through Tuesday/...
as of 1215 PM EST Thursday...
Do not see any clouds on the horizon for aviation and
visibilities should be VFR. Question tonight will be if we get
fog formation over the snowpack with weak warm advection
occuring above it. For now winds should stay up slightly to
prevent this but something to be alert for.
West-northwest winds will be in the 10-15kt range in the
mountains this afternoon, with gusts up to 30 kts, with lighter
winds in the east. Winds will subside more after dusk, but some
stronger winds above the developing surface inversion will
result in low level wind shear along the lwb-roa/bcb corridor
for a few hours this evening.
High pressure will cover the region Friday through Sunday. VFR
conditions are expected as well as warming temperatures.
Moisture will return to west Sunday night into Monday with sub-
VFR conditions possible ahead of another cold front. VFR
conditions should return late Tuesday.
as of 245 PM EST Thursday...
National oceanic and atmospheric administration weather radio, wxl60 (roanoke transmitter) which broadcasts at
162.475 mhz remains off the air. The phone company continues to
investigate and no estimated time has been given for restoring
this. We apologize for the outage.
NC...Winter Weather Advisory until noon EST Friday for ncz001>006-