Area Forecast Discussion
Issued by NWS Raleigh/Durham, NC

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FXUS62 KRAH 251405

Area Forecast Discussion
National Weather Service Raleigh NC
1005 AM 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.


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.


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.


AS OF 355 AM Thursday...

Continued hot on day 3/Sat, but with moderating temperatures and
increasing focus on the tropical N. Atlantic and Gulf of Mexico
through early to mid next week.

The models indicate a strong sub-tropical ridge --one characterized
by mid level heights of 587 dm at 500 mb and 325 dm at 700 mb
centered over nrn ms/al per 00z raob data-- will migrate across the
Central Appalachians and Middle Atlantic states through the weekend.
After another associated hot day on Sat, with low level thickness
values and high temperatures similar to or only very marginally
lower than those of Fri, deep layer nely flow around the NEWD-
expanding ridge will shunt the center of the associated heat WWD
into the TN and OH Valleys by Sunday. The models then remain in
relatively good agreement that the ridge will remain centered over
the Middle Atlantic states, though in a gradually weakened state,
through the end of the forecast period. Under the influence of the
ridge, precipitation chances will remain slim, with the relative
highest (slight chance) invof the sea breeze /over ERN NC/ through
at least Mon.

Model spread remains high with respect to the location and intensity
of what ultimately becomes of the area of disturbed weather that Air
Force Reconnaissance is scheduled to investigate in a few hours
between Puerto Rico and the Bahamas. Forecast uncertainty
consequently remains higher than average for the middle of next
week, so no significant changes have been made to the previous
forecast of increasing moisture/clouds/precipitation chances in
central NC Tue-Wed.


As of 645 AM Thursday...

Under strengthening high pressure, VFR conditions and
light/variable or southwesterly wind will prevail through the TAF
period. there is a small chance of sub-vfr vsbys late tonight,
mainly at KRWI, but given the lack of sub-VFR conditions this
morning and little support from model guidance, confidence is very

Outlook: Persistence of high pressure over the region will
continue to promote VFR conditions, with early morning fog
possible each morning.




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