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000
FXUS62 KRAH 261145
AFDRAH

Area Forecast Discussion
National Weather Service Raleigh NC
745 AM EDT Fri Apr 26 2019

.SYNOPSIS...
A strong cold front will cross central NC this afternoon, proceeded
by numerous showers and a few thunderstorms. High pressure will
build in behind the front on Saturday. This high will drift offshore
Sunday, allowing a dry cold front to cross our region late Sunday
and Sunday night.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 410 AM Friday...

A convectively active weather day expected today (though not in
comparison to last Friday), followed by tranquil weather for the
weekend with seasonal temperatures.

Water vapor imagery early this morning depicts phasing occurring
with the southern stream system lifting through the western
Carolinas, being absorbed by the northern stream system. Convection
associated with the southern s/w has raced eastward into portions of
northern FL/southern GA and the northeast Gulf of Mexico. This area
of convection appears to have temporarily disrupted the 850mb
moisture transport into central NC. This has resulted in just patchy
light rain over the region since midnight with most locations just
receiving a trace. As the convection weakens this morning, expect a
resumption of  the sly flow into our region, leading to a
rejuvenation of showers and potentially a t-storm or two prior to
mid day. With the phasing already underway, a slug of dry air in the
mid layers will likely expand newd across our region later today.
The arrival of this drier air mass will serve to end the production
of showers and storms a few hours sooner than earlier expected.
Thus, expect most locations west of highway 1 to be rain-free by
late afternoon, and over the entire region around or just after
sunset.

Still rather potent dynamics in the atmosphere as a 120kt upper jet
rounds the base of the upper trough this afternoon. Meanwhile low
level sly flow will advect abundant low level moisture primarily
into our Coastal Plain counties later this morning. While surface
based instability marginal, kinematics of sufficient strength to
support/sustain strong updrafts, mainly east of highway 1. Thus,
expect a few strong/severe storms from mid day through late
afternoon over roughly the eastern half of the forecast area with
the threat for severe convection rapidly dwindling after 21Z. Main
weather hazard will be damaging straightline winds, though an
isolated weak/brief tornado cannot be ruled out.

The surge of dry air aloft accompanied by the strong winds aloft
rounding the base of the trough will cause a period of strong gusty
winds along and immediately behind the surface cold front this
afternoon. Anticipate wind gusts in the 30-40 mph range this
afternoon over the western Piedmont, with an isolated gust in excess
of 45 mph possible. Ahead of the front, sly winds over the Coastal
Plain may gust around 30 mph.

Temperatures starting out very mild in the 65-70 degree range.
Expect temperatures to only recover 5-7 degrees across the Piedmont
where shower coverage will be on the increase this morning. If
partial breaks occur across the Sandhills and Coastal Plain, a few
places may reach 80 degrees.

Expect clearing skies this evening, and cooler temperatures
overnight as a drier cooler air mass overspreads the region. Min
temperatures in the 45-50 degree range expected.


&&

.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
As of 415 AM Saturday...

Tranquil weather expected Saturday as high pressure temporarily
extends into our region from a parent high to our south southwest.
Circulation around this weather system will result in wly low level
flow. The slight downslope component will offset modest cold air
advection, resulting in temperatures close to normal for late April,
in the mid-upper 70s. If we mix as high as the GFS suggest, max
temperatures may end up a couple of degrees warmer. A s/w in the
northern stream will skirt to our north Saturday night. This system
will produce a veil of mid/high level clouds over central NC with a
few sprinkles possible overnight north of highway 64.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
As of 312 AM Friday...

A sfc cold front is forecast to drift south across our area on
Sunday. Models continue to depict very limited deep layer moisture
given prefrontal westerly flow, and thus limited rain chances
associated with this front.  So for now will keep forecast dry on
Sunday. Given a late-day fropa, highs should climb into the 80s.

High pressure from the north will follow the front for Monday,
bringing a brief cooling trend.  Dry wx for Monday with highs in the
lower-mid 70s.

Otherwise, Sunday`s front will lift back to our north late Monday or
Monday night, then will be followed by mid-level ridge amplifying
over the Southeast, which should keep our forecast very warm and dry
right through the middle of the week, with the next chance for rain
holding off until the latter part of the work week.

&&

.AVIATION /12Z Friday THROUGH TUESDAY/...
As of 745 AM Friday...

While VFR conditions will occur across most of central NC through
22Z, there will be periods of MVFR conditions associated with
scattered showers and thunderstorms. Breezy sly sfc winds will gusts
around 25kts. In vicinity of the stronger storms, wind gust 40-50kts
probable along with torrential downpours. The convective threat will
diminish in vicinity of the Triad terminals by 20Z, and elsewhere by
00Z. Immediately behind the sfc front, west northwest sfc winds will
gusts 30-40kts in vicinity of the Triad and possibly KRDU. These
gusts will last 1-3 hours then subside to less than 20kts.

VFR parameters expected tonight through Sunday. There will be an
increase in cloudiness Saturday night though it should be mainly
mid/high level clouds. The next chance for sub VFR parameters will
occur early Monday as a stalled sfc front across our region will
likely lead to moisture pooling and the possible development of low
clouds or fog. Low end VFR/MVFR ceilings will be possible for brief
instances Monday into Tuesday.

&&

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

&&

$$
SYNOPSIS...WSS
NEAR TERM...WSS
SHORT TERM...WSS
LONG TERM...np
AVIATION...WSS