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fxus62 krah 221800 
afdrah

Area forecast discussion
National Weather Service Raleigh NC
100 PM EST Wed Feb 22 2017

Synopsis...
high pressure will continue to ridge west into the mid-Atlantic as
the center remains offshore. A slow-moving upper level trough will
cross the southeast and mid Atlantic states through tonight. An
upper level ridge will again briefly build over the eastern U.S.
Thursday and Friday.

&&

Near term /through tonight/...
as of 1010 am Wednesday...

Closed southern-stream low over the northern gom will move east-
southeastward across southern Florida and the Keys late tonight
through early Thursday. With the system suppressed well to our
south, weak forcing via weak upglide and weak DPVA will support
ample cloudiness, but very little in the form of rain in the form
of patchy rain/isolated showers for the remainder of the day.

In-situ wedge in place across the northwest pied that developed in response
to the batch of light precip that moved earlier this morning and
that will likely be sustained by stratus cloud cover within the weak
upslope flow will result in a rather northwest to southeast temperature gradient,
ranging from lower 60s northwest to mid 70s southeast.

Mostly cloudy skies will support another mild night. Lows 50 to 55.

&&

Short term /Thursday and Thursday night/...
as of 255 am Wednesday...

The low over Florida will migrate eastward then northeastward over
the Atlantic on Thursday/Thursday night, allowing the upper level
ridge to once again set up over the southeast U.S. Thursday night.
The surface high will move eastward, though will continue to ridge
into the mid-Atlantic, keeping the surface low suppressed to the
southeast. The best chance for any light rain will be over the far
west early Thursday, but then the far southeast late Thursday and
Thursday night. For now will keep the forecast dry as the models are
having a tough time generating any rain over central NC. Given the
continued influx of warm air into the region, expect another day of
temperatures well above normal, highs in the 70s and lows in the mid
50s.

&&

Long term /Friday through Tuesday/...
as of 310 am Wednesday...

Our weather pattern through this period displays little deviation
from the theme of this winter with above normal temperatures
interrupted by brief cool periods, and below normal precipitation.

A S/W ridge will extend across the region Friday while a sfc high
will be positioned offshore. The low level sly flow advecting a warm
air mass into central NC, coupled with warming aloft attributed to
the mid/upper level ridge will spell well above normal temperatures
Friday afternoon. The partial sunshine and a warm SW flow will
boost temperatures into the 75-80 degree range, a solid 20-25
degrees above normal for late February. These readings will be just
shy of record levels which are near 80-lower 80s (see climate
section below for the details).

The narrow mid-upper ridge will drift offshore Friday night in
advance of a S/W crossing the Great Lakes. The deepening SW flow
will result in very mild overnight conditions and a gradual increase
in cloud coverage. Overnight temperatures will average several
degrees above the normal high temps. Min temps in the 55-60 degree
range anticipated.

The S/W well to our north will drive a sfc cold front across central
NC on Saturday. A marginally moist and a conditionally, slightly
unstable, air mass should support the development of scattered
showers, and possibly a thunderstorm across the coastal plain
Saturday afternoon. The support aloft will be weakening with time
and the model trend has been toward the atmosphere drying out with
time. So while there is still the potential for a few showers, some
locations will not see any rainfall, especially south of Highway 64.
Southwest flow ahead of the front coupled with the warm start to the
day should yield high temps back into the mid-upper 70s, warmest
southeast.

The cold front will sweep east across the region late Saturday and
Saturday evening, ending the threat for showers and skies clearing
west-to-east fairly quick. Temps will cool rapidly Saturday night
reaching into the mid-upper 30s across the Piedmont by early Sunday,
and the lower 40s southeast.

High pressure will build and settle over the region Sunday-Monday
with clear-partly cloudy skies and cooler, but still slightly above
normal, temperatures anticipated. The cool down will be brief as
temps Sunday in the 50s to around 60 will rebound back into the low-
mid 60s Monday. The chilliest night should be Sunday night with
overnight temps in the mid-upper 30s expected. May see lows near 30
in the normally colder locations.

A weakening upper disturbance in the southern stream will approach
from the west Monday night and Tuesday, leading to increasing clouds
and a small threat for light rain. The mild/warm temperatures will
persist.

&&

Aviation /18z Wednesday through Monday/...
as of 1 PM Wednesday...

24-hour taf period: weak southerly upglide, enhanced by an upslope
component at kint and kgso will support low end VFR with brief
periods of MVFR possible through 21z. Elsewhere, VFR ceilings should
prevail. Winds at kint and kgso will generally be light and variable
, while all remaining taf sites should see light south-southeasterly
winds.

With continued weak advection of warm moist air in the southerly
flow, we could see some patchy fog/low stratus develop between 06z
and 12z Thursday, especially at kint and kgso where lift will be
orographically enhanced. Strong daytime heating should burn-off any
fog that develops. Winds will remain light and from the south-
southeast.

Looking ahead: aside from some early morning fog/stratus, expect
predominately VFR conditions through early next week. The exception
will be a very isolated/small chance of a shower or thunderstorm as
a cold front moves through the area Saturday afternoon. Winds will
become breezy Saturday afternoon as the front approaches from the
west, with sustained winds between 15 to 20kts, gusting 25 to 30
kts.

&&

Climate...

Record high temperatures
February 24th February 25th
gso 79/1982 81/1930
rdu 81/1982 82/1930
Fay 83/1930 85/1930

&&

Rah watches/warnings/advisories...
none.

&&

$$

Synopsis...kc/Hartfield

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