Area Forecast Discussion
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FXUS62 KRAH 221736
Area Forecast Discussion
National Weather Service Raleigh NC
135 PM EDT Wed Mar 22 2017
A cold front will push slowly southward through the area today.
Cold high pressure will build into the region from the north
this afternoon through Thursday. Warmer conditions will arrive
this weekend as the high shifts well off in the Atlantic.
.NEAR TERM /THROUGH TONIGHT/...
As of 1015 AM Wednesday...
Main adjustment to the near term forecast was to the sky condition
due to an atmosphere conducive to orographic cloud production.
High pressure will build into central NC this afternoon and tonight
in the wake of the exiting cold front. 12Z upper air analysis
depicts strong low level cold air advection at 850mb, along with a
push of a drier air mass. In addition, strong nw flow between 700-
500mb along with residual moisture has resulted in orographic
induced cirrus across the region. Expect this veil of high clouds to
gradually dissipate as the column becomes drier aloft this afternoon.
While skies will become increasingly sunny, the low level cold air
advection will deter warming. Thus, temperatures will slowly warm an
additional 5-7 degrees from 14Z readings.
12Z GSO soundings depicts fairly stout winds just a few thousand
feet above the surface. This will lead to gusts between 25 and 30
mph, primarily through early afternoon. ~WSS
Tonight, winds will gradually die off to light from the NE. Forecast
soundings do indicate the potential for patchy high cloudiness
overnight. However, this should not hinder the strong cooling
tonight. Lows are expected to fall into the upper 20s and lower 30s
throughout our region. Even though the winds are expected to die off
to 5 mph or less overnight, dew points will be very dry (teens and
lower 20s). This should prevent significant frost. Yet, the actual
lows should dip to freezing for several hours regardless. ~Badgett
.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
As of 255 AM WEDNESDAY...
The strong, cold, dry surface high will build southward from PA/NY
into GA/FL Thursday and Thursday night. Other than a few clouds
due to the upslope easterly flow into the Mountains, skies will be
mainly clear. Highs Thursday are favored to be only 50-55 for the
Northern Piedmont, ranging into the upper 50s near the SC border.
Lows Thursday night will again flirt with freezing in the south and
likely fall into the upper 20s and lower 30s again across the north.
.LONG TERM /FRIDAY THROUGH TUESDAY/...
As of 210 AM Wednesday...
A warming trend is expected late week into the weekend as surface
high pressure will be located off the southeast U.S. coast, with mid
level ridging moving across the area from west to east. This will
result in generally dry conditions from Friday into Saturday night,
before the mid level ridge shifts to the east while a mid/upper
level low moves east-northeastward from the central/southern Plains
into the Ohio Valley and Great Lakes region and eventually across
the northeast U.S. while weakening late weekend into early next
week. This will result in increasing chances for some isolated to
scattered showers and possibly a few storms Sunday into Monday.
However, with the main track of the system now expected to track
well to the north of the area will keep pops in the chance category
(with some locations across the south and east possibly remaining
dry through the period). Temps will be mild, with highs in the 60s
to near 70 Friday, to 70s to near/lower 80s for the weekend into
early next week.
The next southern stream s/w disturbance is expected to track
east/northeastward across the country, possibly phasing with a
northern stream trough on Tuesday over the Ohio Valley/Great Lakes
region. This will result in at least a small chance for showers and
storms on Tuesday, but many question remain on timing and strength
of the system remain. Regardless it appears the mild weather will
continue through the forecast period, with highs in the 70s to lower
.AVIATION /18Z Wednesday through Monday/...
As of 135 PM Wednesday...
High probability that VFR conditions will occur across central NC
through 00Z Saturday. An area of high pressure will build into our
area tonight, then settle overhead Thursday. This weather system
will drift offshore Friday. Brisk northwest winds this afternoon
will gradually subside to less than 10kts by sunset.
The threat for MVFR visibility due to fog will increase early
Saturday morning, and more so Sunday morning, as low level sw flow
advects a warm, moist air mass into central NC. The approach of a
low pressure system will increase the probability of MVFR ceilings
as well as a few showers Sunday through Monday.