Area Forecast Discussion
Issued by NWS Raleigh/Durham, NC

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FXUS62 KRAH 170052
AFDRAH

AREA FORECAST DISCUSSION
National Weather Service Raleigh NC
852 PM EDT Sun Jun 16 2019

.SYNOPSIS...
Southerly return flow will result in much warmer and more humid
conditions returning today and lasting all week. A cold front will
approach from the north on Wednesday, but stall north of the region
through Thursday.

&&

.NEAR TERM /TONIGHT/...
As of 852 PM Sunday...

The latest mesoanalysis shows that the BL has stabilized with the
setting of the sun, thus any lingering shower activity just west of
the Triad should continue to dissipate before reaching our NW zones.
Otherwise, with the subtropical ridge extended across the Carolinas,
look for a quiet night wx-wise.  Latest sfc analysis shows dwpts in
the upper 60s across most of our area, with 70 dwpts just to our
south. Given south sfc flow, those 70 dwpts will reach up into our
southern coastal plain zones overnight, and thus latest hi-res
forecast soundings continue to suggest some patchy low stratus or
fog is possible across our SE zones toward daybreak.  Low tonight on
track for upper 60s NW to lower 70s SE.

Prev near term disc as of 255 PM Sunday...Summer-time pattern
returns today with Bermuda high pressure over the western Atlantic
taking control of the weather pattern across central NC for the next
few days. Both temps and humidity levels return to more seasonable
ranges; afternoon highs ranging from mid 80s NW to near 90 SE with
60 degree dewpoints becoming widely established across central NC.

Synoptic forcing across the area is nearly non-existent as weak
impulses embedded in the quasi-zonal flow aloft look to stay just
north of the area today. Otherwise, the better rain chances will lie
along our western and eastern flanks, via differential heating along
the higher terrain and the inland retreat of the sea-breeze.

Skies will be mostly clear overnight. However, there is an
increasing model signal for the development of stratus/fog across
the far SE zones during the pre-dawn hours. Lows in the upper 60s to
lower 70s.

&&

.SHORT TERM /MONDAY AND MONDAY NIGHT/...
As of 255 PM Sunday...

Humidity and warmth will continue to increase within the continued
southerly return flow about the Bermuda high pressure cell.
Northern/northwestern portions of the NC Piedmont still stand the
best chance of seeing a glancing shot of DPVA from weak shortwave
impulses circumventing the upper ridge extending north into the SE
US. Strong daytime heating in conjunction with any lift/forcing from
any such disturbances within a moist and unstable airmass will
support isolated to  scattered showers and thunderstorms, especially
over the western Piedmont, INVOF of a where the GFS shows consider
sharpening of the nearby lee side sfc trough. Deep layer shear of 20
to 25 kts across southern VA may support an isolated strong storm or
two across the far norther zones. Otherwise, convection should
remain below severe limits. Convection should largely be diurnally
driven, with pops diminishing during the evening and early overnight
hours.

Highs 89 to 94, warmest SE. Lows in the lower 70s.


&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
As of 250 PM Sunday...

The summer-like pattern will continue for the majority of the long
term period as strengthening Bermuda High Pressure remains the
primary synoptic scale influencer. This will promote warmer than
normal temperatures across the region with a gradual rising trend in
shower and thunderstorm activity through mid-week. Generally
isolated to widely scattered airmass thunderstorm coverage is
anticipated Tuesday afternoon and evening, with best chances of
seeing a passing storm remaining west of US-1 and north of US-64,
with the activity fighting low to mid level subsidence  and moderate
capping across the region. Have POPs rising significantly Tuesday
night into early Wednesday as a remnant shortwave trough passes
through the region. Some uncertainty remains on coverage and
intensity of storms here, with the best forcing pushing through the
region prior to peak heating Wednesday afternoon. Weak subsidence
prevails behind the wave, helping to limit overnight convection.
POPs rise again Thursday evening and overnight with storms likely
firing initially along a lee side/pre-frontal trough during the late
afternoon and evening hours, and eventually along the cold front
which is forecast to slide west to east through central NC during
the overnight hours. Will need to monitor this setup for potential
isolated severe storm development, although with the late timing of
the best forcing and generally weak shear and thermodynamic model
profiles, thinking the threat should remain minimal at this point.
Surface subsidence returns behind the front to end the work-week,
with warm yet slightly drier conditions expected for Friday and the
first half of Saturday. Plenty of uncertainty later in the weekend,
with a more amplified GFS returning showers and storm chances to the
forecast as early as Saturday evening while the ECMWF keeps
subsidence a bit stronger, keeping the area dry through Sunday
afternoon.

Afternoon high temperatures will hover in the 87 - 93 range all week
with high moisture content prevalent at the surface through Thursday
(dewpoints hanging out in the 68 - 73 degree range). A 4 to 6 degree
drop in dewpoints is expected behind the front by Friday afternoon
with slow recovery expected through the remainder of the period.
Overnight lows will dip into upper-60s to low 70s through the period
with some stratus and patchy fog development plausible each
morning thanks to the high boundary layer moisture content in place.

&&

.AVIATION /00 MONDAY THROUGH FRIDAY/...
As of 813 PM Sunday...

Through 00Z Tuesday:  The subtropical ridge extended across the
Carolinas will keep most of the t-storm activity mostly north of
central NC through the TAF period.  The exception may be at KINT and
KGSO, where a brief isold t-storm may approach or move across those
terminal Monday afternoon.  Otherwise, mainly VFR conditions are
expected.  Also worth noting that increasing low level moisture may
support a brief period of scattered low clouds (stratus) across the
southern Coastal Plain (and INVOF KFAY) around daybreak Monday, but
right now coverage is not expected to produce a CIG...will monitor.

After 00Z Tuesday:  There will a daily threat, mainly during the
afternoon and evening, of scattered showers and thunderstorms
through Thursday.  Additionally, given the moist/humid airmass in
place, areas of sub-VFR conditions in fog or low clouds is possible
each morning.

&&

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

&&

$$

SYNOPSIS...Badgett/BSD
NEAR TERM...np/CBL
SHORT TERM...CBL
LONG TERM...JJM
AVIATION...np/CBL



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