Area Forecast Discussion
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FXUS62 KRAH 021543
Area Forecast Discussion
National Weather Service Raleigh NC
1040 AM EST Fri Dec 2 2016
High pressure will build southeast from the northern Plains today,
to the Ohio Valley Saturday, then extend down the eastern seaboard
Sunday. A coastal front will develop late in the weekend through
Monday as a storm system takes shape over Texas into the western
Gulf Coast region.
.NEAR TERM /TODAY THROUGH TONIGHT/...
As of 1030 AM Friday...
Other than a few cirrus for a period this afternoon, mainly across
the southern sections, sunny skies are expected. High pressure
over North Dakota will continue to build SE with CAA over the
the eastern states including NC. The high pressure will be slow
to reach the eastern seaboard, only doing so by Saturday night
and Sunday. This will prolong the cool dry conditions for NC.
Highs today are expected to reach the mid 50s to around 60, warmest
in the Sandhills and SE zones. A NW breeze at 10-15 mph will
add to the coolness of the air.
Other than a few cirrus from time to time, mainly southwest, clear
skies tonight are expected. Some mixing should continue through
midnight, give or take a few hours. Then calm conditions will
allow excellent radiational cooling. Lows generally 28-35, coldest
in the Piedmont where the conditions become calm for several hours.
.SHORT TERM /Saturday through Saturday night/...
As of 240 PM Thursday...
The surface ridge, centered over the central Miss Valley early Sat,
shifts NE through the Great Lakes region through Sat night while
continuing to extend SE through NC. Pieces of energy emanating from
the deep low over NW Mexico will slowly break down the ridge as they
ride along its top into NC, resulting in slowly thickening and
lowering clouds, particularly Sat night. Expect mostly sunny skies
early Sat to trend to partly sunny in the afternoon, then to cloudy
Sat night from SW to NE as moist upglide strengthens and deepens in
the mid levels. Expect no pops, however, as the column remains quite
dry below 700 mb. Thicknesses should be slightly lower Sat than on
Fri, suggesting cooler highs in the lower to mid 50s. Increasing
clouds should limit radiational cooling in the SW CWA Sat night,
lesser so in the NE, so expect lows to range from the mid 30s NE to
around 40 SW. -GIH
.LONG TERM /SUNDAY THROUGH THURSDAY/...
As of 335 AM Friday...
Sunday is expected to be a dry and cold day with high pressure to
the north eventually moving offshore by Sunday night and although
weak, could end up being an in-situ damming situation by Sunday
night into early Monday morning. Highs sunday only in the upper 40s
to low 50s. Lows Sunday night in the upper 30s to lower 40s.
On Monday a weak wave will move up the Carolina coast and depending
upon its track could bring some rain to central NC and points east.
The best chances for rain will be across the south and east before a
lull in precipitation on Monday night. Highs in the mid 50s and lows
in the low to mid 40s.
The real weather maker of the long term will be Tuesday and Tuesday
night with a Miller B scenario that will bring two lows out of the
deep south, one which will move up the coast and the other west of
the Appalachians and up through the Tennessee Valley. The upshot is
an extended period of rain on Tuesday with enough dynamic to bring
some heavier amounts to the area. That being said, forecast
soundings are very stable with a strong warm nose over the area that
will be hard to overcome so the threat for any thunder at this time
seems low but a change in the track of the coastal low could change
that. Warmer but a large temperature gradient across the area with
low 50s in the Triad to low 60s in the southeast.
The rain will end Tuesday night and Wednesday and Thursday should be
drier with highs near 60 degrees.
.AVIATION /15Z Friday through Tuesday/...
As of 1040 AM Friday...
High confidence in VFR conditions for the next 24 hours. NW winds
10kt today will diminish to less than 5kt tonight.
Looking beyond 12z Sat: VFR conditions are expected Saturday into
Sunday. However, medium confidence in lowering CIGS Sunday or Sunday
night, MVFR to possibly IFR as a coastal front develops.
Periods of MVFR to IFR CIGS and VSBYS expected Monday through
Tuesday depending on how quickly the storm system expected
to develop over the NW Gulf of Mexico spreads deep moisture into
NC. High confidence in rain/fog/low CIGS sometime early next
week. Timing still in question.