Area Forecast Discussion
Issued by NWS Blacksburg, VA-- Highlight Changed Discussion --
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FXUS61 KRNK 241931
Area Forecast Discussion
National Weather Service Blacksburg VA
331 PM EDT Sun Jul 24 2016
Strong high pressure aloft will continue to bring increasing
heat and humidity through Monday. A series of weak surface cold
fronts approaching from the northwest should gradually bring an
increasing threat for showers and storms by the middle of next
.NEAR TERM /THROUGH MONDAY/...
As of 211 PM EDT Sunday...
A piece of the main upper level ridge over the southwestern US
has broken off and is centered over the southern Appalachains
today. This upper level ridge over the region is expected to sink
south over the next couple of days. Heights over the area will be
at its highest through Monday, therefore the warmest days for the
week looks to be today and tomorrow. Temperatures across the
mountains will peak into the upper 80s to lower 90s with ridges
being a tad cooler. East of the Blue Ridge and into the piedmont,
temperatures will warm into the mid to upper 90s. Dew points
across the south-central piedmont of Virginia will likely remain
in the 70s, producing heat indices values near 105F. A heat
advisory has been issued for this area for Monday.
Otherwise expecting mainly sunny skies with convection quite
limited given little support aloft and warm mid level temps. Still
appears some weak low level convergence across the western ridges
could combine with heating/instability to pop isolated to
scattered slow moving storms across the mountain by mid
Guidance suggesting any evening storms to fade by midnight if not
sooner with the ridge hanging on while more organized convection
stays to the north/west. This should again allow for mainly clear
skies outside of debris clouds overnight, with patchy fog valleys
and muggy lows, mid/upper 60s west to 70-75 east.
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
As of 310 PM EDT Sunday...
Slight drop in 500 mb heights is forecast by the models on
Wednesday. No significant change in air mass this time frame either.
850MB temperatures do not go any lower than +18 through Wednesday
night. There will be some increased low level convergence along the
tail of a weak front that crosses from the northwest into the
forecast area on Tuesday. While the front may stall to the north
there will still be some troffing on the lee side of the
Appalachians on Tuesday and across North Carolina on Wednesday.
Enough daytime mixing on Tuesday and Wednesday to lower surface dew
points in the afternoon. This will keep heat index values in
the piedmont just below heat advisory criteria.
.LONG TERM /THURSDAY THROUGH SUNDAY/...
As of 315 PM EDT Sunday...
Amount of troffing in the eastern United States for the end of
the week is questionable. GFS was the more amplified while the
ECMWF was slightly flatter. Friday looks to be the next day with
any potential for decent upper support. Will have the higher
probability of precipitation on Friday and Saturday afternoon and
.AVIATION /20Z SUNDAY THROUGH FRIDAY/...
As of 128 PM EDT Sunday...
LWB observation have returned as of 17Z Sunday.
Outside of a very isolated diurnal thunderstorm, overall VFR
conditions expected to continue for most of the period with high
pressure aloft in place. Will again see some patchy fog in the
valleys early Monday morning under thin high clouds.
Extended aviation discussion...
Strong high pressure aloft looks to remain in place on Monday with
continued VFR outside of developing convection Monday
afternoon/evening. However coverage of storms on Monday again looks
rather isolated until late and mainly confined to mostly the western
mountains at this point. Ridge will finally weaken through mid week
as an initial cold front sinks toward the area from the northwest.
This should bring about an increase in daily convective coverage
Tuesday into Thursday with periodic MVFR/IFR possible.
Late night and early morning fog will likely occur at the usual
valley locations, and those chances increase across the entire
region if any rain occurs during the afternoon or evening at any
Record high temperatures for today (7/24)
Roanoke.....100 in 1933
Lynchburg...100 in 2010
Danville....101 in 2010
Blacksburg...92 in 1991
Bluefield....91 in 1987
Record high temperatures for Monday (7/25)
Roanoke.....100 in 1934
Lynchburg...102 in 1934
Danville....102 in 2010
Blacksburg...92 in 1987
Bluefield....90 in 1987
VA...Heat Advisory from noon to 8 PM EDT Monday for VAZ046-047-058-