774
FXUS62 KRAH 140736
AFDRAH

Area Forecast Discussion National Weather Service Raleigh NC 333 AM
EDT Sun Jul 1342024

.SYNOPSIS...
A strong subtropical ridge will remain over the Southeast through
early to mid-week.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 330 AM Sunday...

...A Heat Advisory Has Been Issued for portions of the Central
Piedmont, Sandhills, and Coastal Plain Counties...

A flat but strong upper ridge over the SE US coupled with Bermuda
surface high pressure will result in hot and humid conditions over
the next several days. Meanwhile, the lingering sfc front will wash
out into a lee troughing along the eastern slopes of the
Appalachians. The heat returns in strong fashion today as H8 temps
are forecast to warm from 19 to ~22 C this afternoon, with similarly
impressive increase in low-level thicknesses from 1432m to ~1442m.
Afternoon highs are expected to warm into the mid to upper 90s. A
weak/light westerly downslope component will aide in mixing
dewpoints down into the 60s across the western Piedmont, which will
help to mitigate the heat risk. However, dewpoints across the
remainder of the area will consist in the lower to mid 70s, yielding
heat indices of 104 to 109 degrees across the Central Piedmont,
Sandhills, and Coastal Plain counties. In coordination with our
eastern neighboring NWS offices, will issue a Heat Advisory that
will go in effect at 11 am and continue through 7pm.

In terms of rain chances, a very weak, low-amplitude shortwave will
traverse the mid-Atlantic region during the afternoon and early
evening. Weak lift from this feature, as well as the lee side sfc
trough, amidst very steep low-level lapse rates, will support
isolated to widely scattered showers and storms just about anywhere.
Any convection will quickly dissipate after loss of heating with dry
conditions overnight. Lows in the lower to mid 70s.


&&

.SHORT TERM /MONDAY AND MONDAY NIGHT/...
As of 330 AM Sunday...

...Dangerous Heat Persist...

...Record Breaking Temperatures...

The Carolinas will remain under the influence of the upper ridge and
Bermuda high pressure. Models continue to suggest that the heat will
continue to build ever so slightly with record breaking high temps
expected at 2 of our 3 climate sites(GSO and RDU-see climate section
below) as most locations warm into the upper 90s, with some triple
digits/lower 100s possible in the typically warmer locations. A Heat
Advisory in all likelihood will be needed for the same area with
heat indices again topping out in the 105 to 109 degrees.

Some short term relief may come in the form of some widely scattered
convection as the area remains vulnerable to weak disturbances
moving through the area, with the seabreeze expected to be a little
more active.

Balmy overnight lows in the mid to upper 70s, which will also
challenge record hi-min temps.


&&

.LONG TERM /MONDAY THROUGH SATURDAY/...
As of 257 PM Saturday...

The main weather story for Monday and Tuesday will be the intense
heat, given the pattern which features weak ridging and flow aloft,
coupled with H8 temp anomalies of 4-6 deg C above normal.  This will
result in highs in the upper-90s both days, and some low-100s can`t
be ruled out.  Heat indices of 105+ are expected from the Triangle
eastward on Monday, perhaps reaching as far west as the Triad by
Tuesday.  In terms of precip chances those days... coverage should
be isolated at best both days given the overall weak forcing over
the region.

PoPs will increase on Wednesday as heights begin to fall in advance
of a trough moving across the Great Lakes. With increasing flow
above the BL, expect to see the Piedmont trough sharpen and improved
low level convergence and subsequent outflow boundaries should be
the primary lifting mechanisms for increased shower activity. Shower
and thunderstorm activity, which may begin by early afternoon, may
help keep high temps limited to the lower 90s.

Rain chances will continue to increase, with well-above climo PoPs
by Thursday and for Friday and possibly Saturday as well as the
aforementioned trough pushes a cold front into the Mid Atlantic and
Carolinas regions before stalling over us.  That boundary, coupled
with another plume of deep moisture will likely result in several
rounds of heavy rains.  However, that will also keep temps limited
to near-climo values.

&&

.AVIATION /06Z SUNDAY THROUGH WEDNESDAY/...
As of 100 AM Sunday...

Aside from some patchy fog at fog prone locations like KRWI, VFR
will generally prevail overnight and into the afternoon. Isolated to
widely scattered diurnally driven showers and storms are possible
area-wide and have handled this low probability with tempo group
between 19 to 22z at all TAF locations.

Outlook: Isolated afternoon storms could result in sub-VFR conditions
at TAF sites early this week, but otherwise VFR conditions are
expected until the next front settles into the region with higher
chances of convection and flight restrictions late Wed-Thu.

&&

.CLIMATE...

Record High Temperatures:

July 14:
KRDU: 101/1954

July 15:
KGSO: 97/1974
KRDU: 99/1997

July 16:
KGSO: 99/1915
KRDU: 101/1887
KFAY: 103/1937

July 17:
KRDU: 100/1887
KFAY: 102/1932


Record High Minimum Temperatures:

July 13:
KGSO: 75/2017
KRDU: 78/2017
KFAY: 78/2017

July 14:
KGSO: 77/1981
KRDU: 77/2017
KFAY: 80/2017

July 15:
KGSO: 74/2019
KRDU: 76/1992
KFAY: 78/2015

July 16:
KGSO: 75/2010
KRDU: 77/2010
KFAY: 78/1992

July 17:
KGSO: 75/2013
KRDU: 80/1887
KFAY: 77/2019

July 18:
KGSO: 76/1986
KRDU: 79/1887
KFAY: 77/2019

July 19:
KGSO: 75/2016
KFAY: 77/2023

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
Heat Advisory from 11 AM this morning to 7 PM EDT this evening for
NCZ008>011-025>028-040>043-075>078-084>086-088-089.


&&

$$
SYNOPSIS...MWS
NEAR TERM...CBL
SHORT TERM...CBL
LONG TERM...np
AVIATION...CBL/BLS
CLIMATE...RAH