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000
FXUS62 KRAH 182323
AFDRAH

Area Forecast Discussion
National Weather Service Raleigh NC
722 PM EDT Tue Jul 18 2017

.SYNOPSIS...
An upper level low across the Piedmont of North Carolina will drift
east and then southeast across the Carolinas through Thursday. A
strong ridge of high pressure across the Central Plains will expand
into our region for Friday through the weekend.
&&

.NEAR TERM /THROUGH TONIGHT/...
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As of 715 PM Tuesday...

Numerous trees and power lines downed in Winston-Salem with late
afternoon wet microbursts. Other severe storm warnings continue now
to the south of this region in the Troy, Albemarle, Rockingham, and
Wadesboro areas. These storms were moving/developing southward and
should be weakening with loss of heating in the next hour or two.
Another cluster of severe storms was moving southward along the
entire northern tier of counties of the Piedmont, but these should
weaken as well, but could still remain SVR for another hour as they
threaten Roxboro, Henderson, Oxford, etc... as there is residual
MLCAPES of 1500 J/KG to work with over the Piedmont where it has not
been convectively overturned. We will update again to push the 50-70
POP for the Piedmont and Sandhills through mid-evening, with nothing
much along the I-95 corridor away from the convective activity.

The convection should wane by 900 or 1000 this evening with the loss
of heating and limited forcing for ascent. Overnight lows will range
within a few degrees of 70.
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&&

.SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/...
As of 215 PM EDT Tuesday...

The upper trough will have become closed by Wednesday morning
and will be centered near Goldsboro with a northeast-southwest
trough axis. Convective coverage on Wednesday afternoon and
evening will be more limited than previous days as the deep
moisture axis will have shifted offshore and much of the area
will be located on the subsident side of the trough. Will
include slight chance PoPs for much of the area with slightly
higher Pops across the Coastal Plain, east of the trough axis.
The convection should dissipate early Wednesday evening. High
temperatures on Wednesday will be a few degrees higher as
morning low-level thickness values increase to 1410m or greater,
supporting highs in the 89 to 94 range. Lows on thursday
morning will range in the lower 70s. -Blaes
&&

.LONG TERM /THURSDAY THROUGH TUESDAY/...
As of 249 PM Tuesday...

The upper level low developing over the Mid-Atlantic today will
remain over the region through Wednesday. The low will slowly
migrate southward then southwestward Thursday and Thursday night
along the eastern periphery of the ridge located over much of the
Central U.S. A second upper level ridge will be located over the
Atlantic during that time. Central NC will remain between the two
highs through Friday night and as a result expect a mostly dry, but
hot period, with convection chances limited to the far NW and SE. At
the surface, a lee trough will linger over the region, with high
pressure over the Atlantic. The result will be continued southwest
flow ushering in warm moist air. Expect highs to be in the mid to
upper 90s  and dewpoint temperatures in the upper 60s NW to mid 70s
SE through the weekend, with heat indices largely in the 100-106
range. Overnight lows will not provide much relief as they climb
from mid 70s Thursday night to the mid to upper 70s for the
remainder of the week and weekend. As stated in the previous
discussion, convection will be mainly diurnal and limited to the
differential heating zones over the mountains and along the sea
breeze.

For early next week, an upper level trough will start to amplify
over the Eastern U.S. while the aforementioned low that settled over
the northern Gulf Coast gets absorbed into the trough. Expect
increased precip chances during that period, though temperatures
should decrease some, highs in the low to mid 90s.

&&

.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
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As of 715 PM Tuesday...

24 hour TAF period... Scattered MVFR to IFR conditions will linger
in between the KRDU/KGSO/KCLT terminals through 02z or so, then
mainly VFR conditions are expected this evening and overnight.
Another period of stratus is expected to redevelop late tonight
although the coverage will be more limited and generally confined to
the eastern Piedmont and especially the Coastal Plain.

Looking further ahead... Mainly isolated afternoon and early evening
storms are expected again on Wednesday, but in general VFR
conditions expected with building high pressure aloft mid week
through Friday. The is also a low probability of fog/low stratus in
the morning across the east.
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&&

.CLIMATE...
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RDU Records:
Date     | High   Year  |  High Min  Year
------------------------------------------

20 July  |  102   1942  |     76     1981
21 July  |  102   2011  |     78     1932
22 July  |  103   2011  |     78     2011
23 July  |  105   1952  |     78     2011
24 July  |  101   2011  |     79     2011

GSO Records:
Date     | High   Year  |  High Min  Year
------------------------------------------

20 July  |  100   1977  |     75     1986
21 July  |  102   1926  |     76     2011
22 July  |  101   1926  |     77     2011
23 July  |   99   1952  |     78     2010
24 July  |   99   1914  |     78     2010

FAY Records:
Date     |  High  Year  |  High Min  Year
-------------------------------------------

20 July  |  104   1932  |     80     1996
21 July  |  105   1932  |     79     1977
22 July  |  107   1932  |     79     2011
23 July  |  103   2011  |     79     1998
24 July  |  105   1952  |     79     1945
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&&

.RAH WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$
SYNOPSIS...BLAES
NEAR TERM...Badgett
SHORT TERM...BLAES
LONG TERM...KCP
AVIATION...Badgett
CLIMATE...RAH