Area Forecast Discussion
Issued by NWS Raleigh/Durham, NC-- Highlight Changed Discussion --
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FXUS62 KRAH 282333
Area Forecast Discussion
National Weather Service Raleigh NC
732 PM EDT Fri Apr 28 2017
A warm moist southerly flow will continue through the weekend, as a
deep high pressure ridge strengthens off the Southeast coast.
.NEAR TERM /through tonight/...
As of 305 PM Friday...
Quiet and warm weather expected tonight. The mid level anticyclone
will continue to build over and just off the Carolina and Southeast
coast, ensuring net subsidence aloft, with steady warming through
850-700 mb, keeping the column capped. Low level flow from the S and
SW will continue to draw low level moisture into the area, with
gradually increasing moisture transport, and this combined with the
strengthening cap through the 950-850 mb depth should foster
development of stratus overnight. Forecast will show a trend toward
mostly cloudy skies overnight. Expect lows in the 66-71 range. -GIH
.SHORT TERM /Saturday and Saturday Night/...
As of 315 PM Friday...
Persistence will rule through Sat night, as the mid level
anticyclone continues to build just off the NC coast, and the
surface ridge noses strongly westward over the Southeast. Expect
another largely dry day despite high MUCAPE values of 3000-4000
J/kg, as it coincides with a lack of dynamic forcing for ascent and
limited moisture as PW falls further. And the orientation of the mid
level anticyclone will shunt any isolated mountain convection well
to our NW. Thicknesses are projected to be nearly 40 m above normal
with plenty of isolation, yielding much above normal highs in the
upper 80s to lower 90s, with heat index values peaking well into the
mid to perhaps upper 90s. Warm and muggy Sat night, with another
round of late-night stratus expected. Lows in the upper 60s to
around 70. -GIH
.LONG TERM /SUNDAY THROUGH FRIDAY/...
As of 247 PM EDT Friday...
Sunday the surface high will retreat eastward as a low pressure
system moves across the central plains with a cold front extending
down the Mississippi Valley. This will keep central NC in the
southwesterly return flow regime and the warm temperatures will
continue. Expect highs in the low to upper 80s with highest
temperatures across the east with increasing clouds in the west
keeping conditions cooler. Most of the day should be dry but cant
rule out a stray afternoon shower or thunderstorm.
The system to the west will cross the area Monday and Monday night,
thus chances for precipitation go up considerably by Monday
afternoon. Thunder will certainly be possible but the chances for
severe seem pretty low at this time. Models are having a hard time
nailing down how much QPF will be realized at this time. The front
will come through and precipitation threat will end by daybreak on
Tuesday. Behind the front, temperatures will moderate back into the
mid to upper 70s. More of the same for Wednesday with temps rising
back into the lower 80s in the east.
By Thursday precip chances begin to increase once again as the Gulf
of Mexico opens up and a series of shortwaves march towards the
Carolinas with a stronger low pressure system forming by the end of
next week into the weekend. This will keep weather unsettled with
the treat for showers and storms Thursday and Friday with
temperatures backing off into the 70s on Thursday and the upper 60s
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
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24 Hour TAF Period: VFR conditions will continue this evening with
dry conditions association with an expanding mid/upper level area of
high pressure located just off the Southeast U.S. coast. However,
abundant low level moisture will lead to redevelopment of IFR cigs
overnight, most likely after midnight at all TAF locations (first
KFAY/KRWI, then spreading northwestward). Winds will stay up at 6-12
kts overnight. Thus do not expect any fog tonight. The prevailing
IFR cigs will rise to MVFR after 14z or so, then to VFR after 16z or
so. Expect skies will become mostly sunny by noon, with a
southwesterly wind at around 10-13 kts, with gusts of up to 17-20 kts
Outlook: VFR conditions will hold through Sat evening, with a good
chance of sub-VFR stratus late Sat night into Sun morning, followed
by VFR conditions the remainder of Sun, and afternoon storm chances
confined to the mountains. The risk for sub-VFR conditions will
increase Sun night through Mon, with a better chance of showers and
storms Mon through Mon night as a cold front approaches from the
west (although this front will dissipate before it gets into the
area). VFR conditions are expected Tue into Wed.
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