Area Forecast Discussion
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FXUS62 KRAH 270124
Area Forecast Discussion
National Weather Service Raleigh NC
924 PM EDT Thu May 26 2016
.SYNOPSIS...High pressure will extend over the area through
Friday. Meanwhile, a storm system will develop over the western
Atlantic and drift toward the Southeast U.S. coast through the
.NEAR TERM /through tonight/...
As of 924 PM Thursday...
Convection associated with the lingering upper shear axis over
western NC, caught/trapped with in the upper level ridge axis in
place across the region has diminished with loss of heating. Outside
of an isolated shower across the far western Piedmont, remainder of
the night will be dry.
The continued modification of the low level atmosphere along with
patchy mid level cloudiness will support mild overnight
temperatures. Min temps in the mid 60s.
.SHORT TERM /Friday through Friday Night/...
As of 335 PM Thursday...
A narrow ridge of high pressure aloft will extend west-east across
central NC. This feature will maintain a mid level cap and inhibit
convective development over most of the region. The exception may be
the far west-nw where outflow boundaries from overnight convection
and linger weak upper level disturbance may enable an isolated
shower or storm to develop during the heat of the day.
Low level thicknesses comparable to today, supportive of afternoon
temps well into the 80s, near 90 in the Sandhills and Coastal Plain.
Continued mild overnight with min temps in the mid 60s.
.LONG TERM /Saturday through Thursday/...
As of 230 PM Thursday...
The main forecast concern for this period continues to be the
potential tropical/sub-tropical development of an area of low
pressure between the Bahamas and Bermuda this weekend.
The upper level ridge responsible for the recent quiet weather will
break down as the coastal low develops. To the west, an upper level
trough will linger for the weekend. A shortwave will progress from
the southern Rockies northeastward along the trough axis toward the
As the upper level short wave moves through the Great Lakes, the
northeastward moving coastal (tropical) low will progress toward the
SC coast. As of the most recent runs, the models indicate these two
features interacting Sunday night/Monday. The upper level shortwave
could absorb the coastal low (possible tropical system) on Monday.
There is still a fair amount of uncertainty on whether the low will
move up the Mid-Atlantic coast or hand out along the Carolina coast
before slowly moving inland. Regardless of this, the majority of
this period appears to be fairly unsettled, with chances for
convection, highest in the aft/eve, everyday. Much of the coverage,
duration, and timing of convection will depend on how the system evolves
and thus confidence is still somewhat low. With the strong advection
of Atlantic moisture into the region on the northern edge of the
low, expect increasing clouds from the east on Saturday, though much
of the day will remain dry. Cloudy skies could persist through much
of the period.
Temperatures through the period: with the increasing clouds and
chances for rainfall, expect highs to decrease from the mid 80s on
Saturday, to upper 70s to low 80s Sunday. Highs should slowly
moderate back into the mid 80s by the middle of the week. Overnight
lows will remain fairly steady in the mid to upper 60s.
.AVIATION /00Z Friday through Tuesday/...
As of 726 PM Thursday...
VFR conditions will persist across central NC through Friday. The
exception will be a small risk for early morning fog, limiting the
visibility to MVFR criteria for a brief period.
Aviation conditions Saturday will vary between VFR and MVFR criteria
as increasing moisture results in lowering cloud bases and an
enhanced threat for afternoon and evening showers and
Sub VFR conditions with showers and low ceilings are likely Sunday
and Memorial Day due to an area of low pressure that will likely be
at or near the coast then.