Area Forecast Discussion
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FXUS62 KRAH 220919
Area Forecast Discussion
National Weather Service Raleigh NC
420 AM EST Wed Feb 22 2017
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 240 AM Wednesday...
Low pressure over the Mississippi River valley will slide southeast
over the eastern Gulf of Mexico today and over Florida tonight. The
bulk of the rainfall associated with that system will remain well
south of Central NC. However, increasing southeasterly return flow
into the area from both the high offshore and the aforementioned low
over the Gulf, combined with the diffuse diffuse trough aloft moving
over the region, will result in the development of showers across
the west, possibly lasting into the early afternoon. Temperatures
this morning will be a bit atypical with around 50 degrees in the
west and mid 40s in the east. The increasing southeasterly flow
advecting warm Atlantic air into the region will yield highs in the
low to mid 70s across the southeast. With the lingering light rain
and clouds across the west, highs are only expected to get into the
low 60s, however should clouds and rain clear out earlier, the highs
could be several degrees higher. Lows tonight in the upper 40s NW to
low 50s SE.
.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
.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
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
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
.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
As of 100 AM Wednesday...
24-Hour TAF period: Somewhat of a low-confidence TAF forecast the
next 24 hours. However, the expectation is for fog/low stratus to
develop across the east around 08-10Z and in the north and west
around 09-12Z. Cigs could drop into the LIFR range though visbys are
expected to remain MVFR or VFR. The duration of sub-vfr cigs and the
extent of improvement beyond the 12-15Z time frame is variable
across the area, but expect the best chance for and greatest
improvement to be at KFAY and KRWI. KINT and KGSO could remain MVFR
through late in the TAF period. The best chance for light rain will
also be at KINT and KGSO through the overnight and into early
Wednesday afternoon. The greatest uncertainty/variability will
likely be at KRDU, but will keep the trend there closer to that of
KFAY and KRWI for now.
Looking ahead: With continued southeast flow through Friday, the
early-morning sub-VFR cigs and visbys will likely be a reoccurring
theme. Low clouds may scatter out enough during the daytime hours
for a return to VFR. Winds will slowly veer through the period ahead
of the approaching cold front. Showers and sub-vfr conditions will
also be possible ahead of the front, which is expected to move
through Central NC on late Saturday. A return to VFR conditions is
expected for Saturday night/Sunday.
-- Changed Discussion --Record High Temperatures
February 24th February 25th
GSO 79/1982 81/1930
RDU 81/1982 82/1930
FAY 83/1930 85/1930
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