Area Forecast Discussion
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FXUS62 KRAH 261951 RRA
Area Forecast Discussion
National Weather Service Raleigh NC
252 PM EST Sun Feb 26 2017
High pressure over the area will move offshore late tonight and into
the day on Monday. A warm front will approach from the south Monday
night, then move north of the region Tuesday. Warm southwesterly
flow will continue ahead of a cold front approaching from the west.
NEAR TERM /TONIGHT/... As of 250 PM SUNDAY...
Flow aloft has become quasi-zonal in the wake of upper trough
exiting the Mid-Atlantic region. While at the surface, modified cP
parent high centered over the TN Valley this morning will shift east
over the area through the afternoon and then slip offshore late
tonight and into the day on Monday.
Batch of broken high clouds in advance of the sheared shortwave
energy ejecting eastward across the Lower MS Valley will bring an
increase in high clouds late tonight/during the predawn hours Monday
morning, which could temper low temps just a bit. Overnight lows in
.SHORT TERM /MONDAY AND MONDAY NIGHT/...
As of 250 PM SUNDAY...
Surface ridge axis will extend west into the area from the parent
high centered off the Mid-Atlantic coast. Resultant southerly-
southeasterly low-level flow will allow for moderation of cP airmass
with highs Monday a good 7 to 10 degrees warmer than Sunday. Highs
ranging from lower 60s NW to upper 60s/near 70 SE.
Strengthening southwesterly low-level WAA ahead of the sheared low-
amplitude shortwave trough moving into region will result in
increasing clouds by the late afternoon with isolated to scattered
showers possible during the evening and into the overnight hours.
The NAM is especially wet as it develops 500-750 J/Kg of elevated
instability across the area, but believe this to be a bit overdone.
Much warmer overnight lows in the upper 40s to lower/mid 50s.
.LONG TERM /TUESDAY THROUGH SATURDAY/...
As of 355 AM Sunday...
A warming trend will continue early next week, peaking on Wednesday
in advance of a strong cold front. However, deep southwesterly flow
early to mid next week will allow for plenty of moisture/clouds
along with periods of isolated to scattered showers Tuesday through
Wednesday. A band of showers and thunderstorms will likely accompany
the strong cold front late Wednesday into early Thursday morning.
Deep layer shear will be impressive with this system, on the order
of 50-60 kts, but diurnal timing will be poor with any convective
line moving across the area overnight. Nonetheless, we should at
least see some storms, with at least a small severe threat
(depending on the amount of instability). High temps Tuesday and
Wednesday are expected to generally be in the 70s, with possibly
some lower 80s on Wednesday across southern and eastern portions of
the area. Low temps will follow a similar trend, well above normal,
in the upper 50s to lower 60s on Wednesday morning.
Dry weather is generally expected behind the front as surface high
pressure is expected to initially build into the area, before a
reinforcing dry cold front moves across the area on Friday. High
temps behind the initial front late next week are expected to be in
the 60s. High Friday and Saturday are expected to be in the 50s to
near 60 south. Low are expected to be in the 30s late week into the
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
As of 1227 PM Sunday...
24 Hour TAF Period: There is high confidence of VFR conditions
through the 24 hour TAF period, as surface high pressure moves east
across the region, becoming positioned off the NC coast Monday
afternoon. Northwesterly winds in the 6 to 11 kt range will become
light as variable late this afternoon and evening as the high shifts
overhead, and will become south-southeasterly on Monday.
Outlook: Warm moist air advection ahead of a upper level disturbance
could produce the next chance for sub-VFR conditions Monday night
with isolated to widely scattered showers possible. Scattered
showers along with the threat of sub-VFR conditions could linger
into Tuesday and Tuesday night. A cold front passage late Wed night
or early Thu will bring a better chance for showers and possibly a
few thunderstorms. Cool high pressure building into the area
Thursday and Friday will bring a return to VFR conditions for late
in the week and into the weekend.