Area Forecast Discussion
Issued by NWS Blacksburg, VA
FXUS61 KRNK 251858
Area Forecast Discussion
National Weather Service Blacksburg VA
258 PM EDT Tue Apr 25 2017
Low pressure centered over the eastern North Carolina this afternoon
will slowly drift northeast and off the coast tonight into
Wednesday. High pressure will build in Wednesday and continue for
the second half of the week. This will result in a considerable
boost to the temperature with above seasonal warmth expected by the
.NEAR TERM /THROUGH WEDNESDAY/...
As of 255 PM EDT Tuesday...
WSR-88D showed showers are diminishing or dissipated across
most of the forecast area. However, there are still some pockets
of drizzle and light rain. Low pressure centered over eastern
North Carolina this afternoon will move northeast off the
Atlantic coast tonight into Wednesday. High pressure over the
Ohio Valley will build east tonight into Wednesday.
HRRR and Hiresw-arw-east try to develop some isolated showers across
the high terrain this afternoon into this evening. Believe any
shower or light rain/drizzle will be limited. Mid level ridging
builds in from the west this evening into tonight. For tonight, any
clearing will set the stage for fog formation. Unless the stratus
persists, anticipate development of fog per wet ground, diminishing
winds and radiational cooling from the departing mid/upper level
cloud cover. Low temperatures tonight will range from the mid 40s in
the mountains to the lower 50s in the Piedmont.
High pressure will build over the Southeast States Wednesday. Any
fog Wednesday morning will quickly dissipate leaving sunshine for
Wednesday afternoon. With increasing heights and warming
thicknesses, 85h temperatures will climb to near +15 deg C for
Wednesday. Temperatures may be a degree or two cooler than one would
think, as the initial surge of warmth will go into latent heating
and an attempt to evaporate all of this moisture laying around from
the multiday rain event. High temperatures will vary from near 70 in
the mountains to the upper 70s in the Piedmont.
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY NIGHT/...
As of 258 PM EDT Tuesday...
A low amplitude upper ridge will give way to a broad trof over the
upper midwest with short wave shearing off to our northwest. This will
drive a surface low from the Great Lakes into Canada and drag a
trailing cold front into our region late Thursday into Thursday night
with basically high chance POPs for scattered showers/some thunder.
High pressure brings us a basically dry day for Friday before a warm
front lifts north through the region Friday night with chance for
By Friday, we develop a Bermuda high off the coast with ridging aloft
and a deepening trof/closed low over the midwest. This will develop a
deep southerly flow of warm and moist air that will pump the heat and
humidity up by late in the week. Expect highs Friday to reach the mid
80s east of the Blue Ridge with upper 70s/lower 80s to the west.
.LONG TERM /SATURDAY THROUGH TUESDAY/...
As of 258 PM EDT Tuesday...
We will be in a very summerlike pattern this weekend with very warm and
humid conditions and an increasing chance for showers and thunderstorms
each day, especially along the Blue Ridge. By Monday, the vertically
stacked upper closed low over the midwest will move into the Great
Lakes region. This will push a vigorous cold front into the area from
the west with a good chance of showers and thunderstorms through Monday
afternoon. High pressure will then build on for Tuesday with cooler
weather and windy conditions.
.AVIATION /19Z TUESDAY THROUGH SUNDAY/...
As of 147 PM EDT Tuesday...
MVFR ceilings with pockets of IFR with rain,drizzle and fog
will prevail this afternoon into tonight. The upper level low
will slowly drift northeast tonight and away from the area
Wednesday. An increasing pressure gradient around the area of
low pressure will also result in stronger gusty northeast winds
this afternoon into this evening, then winds become light and
variable tonight into Wednesday morning.
Areas of low clouds and fog will develop tonight with IFR
conditions expected into Wednesday morning. Conditions will
become VFR by Wednesday afternoon. Winds will remain light
High confidence in ceilings, visibilities and winds during the
Extended Aviation Discussion...
Better flying weather is expected for the second half of the
week, though another front may bring scattered MVFR
showers/storms Thursday afternoon and evening across the
mountains. Drier and much warmer weather will return for Friday
and Saturday with temperatures much above normal for the
weekend. Can not completely rule out an isolated MVFR
thunderstorms along the southern Blue ridge. Scattered MVFR
showers and thunderstorms are possible Sunday and Monday.
As of 258 PM EDT Tuesday....
Significant rainfall has ended across the region allowing water levels
to gradually subside at all locations except along the Dan and Roanoke
The Dan is expected to crest early tonight above major flood stage at
Danville, then begin falling later tonight. Crests at Paces and South
Boston are not expected until late Wednesday. Further upstream, the Dan
crested at moderate flood stage at Wentworth and will be falling slowly
The Roanoke river at Randolph will experience moderate flooding with a
crest late tomorrow.
Please refer to the latest flood statements for further details.