Area Forecast Discussion
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FXUS62 KRAH 280606
Area Forecast Discussion
National Weather Service Raleigh NC
200 AM EDT SUN AUG 28 2016
High pressure will persist over the region through today. An upper
level disturbance over the Atlantic will then drift west along the
Carolina coast Monday and Tuesday
.NEAR TERM /THROUGH TONIGHT/...
As of 1018 PM Saturday...
Convection continues to wane with lingering isolated storms drifting
slowly westward over the central/western piedmont before diminishing
all together as low-level surge of lower theta-e air and increasing
CIN advects into the area behind a weak surface front moving in from
the ne. This nely low-level flow could also result in the
development of some low stratus and/or fog across the NC Coastal
Plain during the predawn hours, possibly spreading westward into the
Central Piedmont/Triangle area aoa daybreak.
Lows tonight 70 to 75, coolest across the ne.
.SHORT TERM /SUNDAY THROUGH SUNDAY NIGHT/...
As of 350 PM Saturday...
Surface high pressure centered over southern New England will
strengthen and nose southward into the Carolinas Sunday. This sfc
feature will extend across our Piedmont counties. Associated
subsidence should initially limit mixing which may allow low clouds
to linger until late morning/mid day. Otherwise, presence of sfc
ridge should inhibit convective development in the afternoon hours.
Over the southern coastal plain and the sandhills, modest moisture
advection courtesy of an upper level low off the SC coast coupled
with afternoon heating should trigger scattered convection. Expect
the greatest concentration to occur immediately se of our region
though 30-40 percent coverage still possible over parts of our se
Anticipated cloud cover Sunday morning will limit sunshine. this
should to afternoon temps not quite as hot/oppressive as the past
couple of afternoon. High temps upper 80s-lower 90s.
Again, most of the convection will dissipate with loss of heating.
Could see another round of overnight low clouds, though it may be
limited to the se half of the forecast area. Low temps upper 60s nw
to the low/mid 70s se.
.LONG TERM /MONDAY THROUGH SATURDAY/...
As of 226 PM SATURDAY...
Monday through Wednesday: The models still indicate a mid- to upper-
level low over the western Atlantic will move westward along the
southern periphery of the high from Bermuda to the east coast of the
U.S. through early next week. The high will weaken as the low
approaches and stalls along the Carolina coast through Wednesday. At
the surface, some weak ridging lingers over western NC as the low
sits just off the coast. Surface winds will be primarily
northeasterly. Chances for showers and storms should remain limited
to the southern and southeastern portions of Central NC. Highs will
be in the mid 80s to around 90 degrees and lows in the upper 60s to
low 70s expected.
Thursday through Saturday: An upper level trough will amplify over
the eastern U.S. Wednesday night and Thursday, when it`s expected to
absorb the stalled coastal low. The trough axis should then shift
offshore late in the week. At the surface, a cold front is forecast
to slide southward into Central NC Thursday night or Friday,
although the extent of southward progression is still fairly
uncertain. Highest confidence of frontal passage in the northeast
and lowest in the southwest. As a result, best chances for
convection will be with the front as it moves into and stalls over
the Carolinas, though that will also depend on the diurnal timing.
The temperature forecast gets a bit more difficult with the
aforementioned front, but for now expect a decrease in highs from
near 90 degrees on Thursday into the mid 80s Friday and Saturday
with lows generally in the mid 60s to low 70s.
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
As of 200 AM Sunday...
Early showers and storms have pushes west through the southern
Piedmont and conditions are mostly VFR across the area at 06Z. Skies
have mostly cleared across eastern NC, which may lead to some fog
after 08z, though northeasterly flow may favor more low clouds than
fog, possibly as low as LIFR. Confidence is pretty high that RWI
and FAY will see IFR or LIFR conditions by 09z. To the west, RDU
may end up right on the end of the low clouds, but sub-VFR vsbys
will still be possible at RDU, GSO, and INT given earlier rainfall.
If stratus does indeed develop over the coastal plain, models
suggest it will be slow to lift through the morning hours, with a
period of MVFR ceilings as far west as RDU between 12z and 15z.
Scattered storms will likely develop later this afternoon, mainly
from FAY to RWI and to the east.
VFR conditions are expected to prevail across central NC through
most of the upcoming work week. There will be a good chance for
early morning IFR/low end MVFR conditions each day due to low clouds
and/or fog. In addition, there will be scattered showers and storms
each afternoon, with the highest concentration expected in the
vicinity of KFAY.