Area Forecast Discussion
Issued by NWS Raleigh/Durham, NC-- Highlight Changed Discussion --
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FXUS62 KRAH 251837
Area Forecast Discussion
National Weather Service Raleigh NC
237 PM EDT THU AUG 25 2016
High pressure will extend across the region through the remainder of
the week, as a strong upper level ridge builds overhead.
.NEAR TERM /THROUGH TONIGHT/...
As of 1005 AM Thursday...
Little change required to the near term forecast.
An area of high pressure at the surface and aloft will maintain hot
and dry conditions across central NC this afternoon. Temperatures
appear on track to reach near 90-lower 90s.
Isolated convection may threaten/skirt our nw counties later this
afternoon as orographic lift and available moisture aid to initiate
convection over the higher terrain. Mean steering flow would
translate the isolated cells toward the nw Piedmont. However,
morning analysis depicts deep anti-cyclonic flow over the region,
not conducive to convective development/maintenance. Thus, do not
expect any appreciable rain to occur over the Triad region at this
Tonight, presence of high pressure will maintain dry conditions.
Modifying air mass will result in overnight temperatures a couple of
degrees warmer than previous nights. Min temps upper 60s-around 70.
.SHORT TERM / FRIDAY THROUGH 6 AM FRIDAY/...
As of 345 AM Thursday...
The center of the upper ridge -forecast at 594dm- will shift east
and be centered over southwest VA on Friday, bringing the 850mb
thermal ridge across northwest NC and southern VA. 850mb temps
around 21C favor highs in the upper 90s, and while mixing may not be
quite that deep, highs should be on the upper end of guidance, 93-
96. dew points creeping back into the lower 70s area while will
spell a return of humid conditions and heat indices back around
100F. A weakening cold front is forecast to drop into VA Friday
evening, but ahead of the front lows on Friday night will be in the
lower 70s for most areas.
.LONG TERM /SATURDAY THROUGH THURSDAY/...
-- Changed Discussion --AS OF 235 PM Thursday...
Saturday through Sunday night: The weekend is setting up to be
mostly dry as an upper level ridge sits directly on top of central
NC. At the surface a high pressure system will start Saturday over
the Great Lakes before progressing to the northeast through New
England and the Canadian Maritimes. Models try to generate a few
showers, particularly on Saturday afternoon across the western
portion of the CWA. Will put slight chance in the forecast but
confidence on this actually occurring is fairly low given the strong
subsidence overhead. Saturday will be hot with maximum temperatures
in the mid 90s but dewpoints should stay in the low 70s. This will
result in heat indices creeping into the 100-105 degree range but
probably wont be enough for a heat advisory. Temperatures will drop
back to near 90 degrees on Sunday afternoon.
Monday through Thursday: Model solutions begin diverging early next
week so details will be hard to pin down at this point but we do
know that the upper level ridge should relax and upper flow will
become more zonal north of the area. To the south, the pattern will
largely be dictated by where the current tropical invest winds up.
Forecast model track spread is very large at this point as is the
Have increased chances for precipitation into the chance range for
the end of the forecast period to account for any possible effects
of the tropical system. Once the ridge breaks down the storm will be
allowed to recurve the question is how far west will it be by that
time and how quickly will it recurve. If the storm recurves before
reaching the Florida Peninsula we could see dry weather here in NC
as the storm goes out to sea. However if the storm recurves in the
Gulf further west, then we could see rainfall ahead of the storm as
early as Thursday morning. Highs near 90 each day with lows in the
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.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
As of 120 PM Thursday...
There is high confidence that VFR conditions will persist across
central NC through Friday night. The exception will be scattered
pockets of MVFR/IFR visibility between 09Z-12Z, mainly in the
sandhills and coastal plain. This possibility appears highest in
vicinity of KRWI. Otherwise, an area of high pressure will maintain
dry weather with light wind conditions.
This area of high pressure is expected to maintain its influence
over our region through early next week. This suggest an extended
period of VFR conditions, aside from patchy early morning MVFR/IFR