Area Forecast Discussion Issued by NWS Raleigh/Durham, NC
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000
FXUS62 KRAH 180015
AFDRAH
Area Forecast Discussion
National Weather Service Raleigh NC
815 PM EDT Sun Mar 17 2024
.SYNOPSIS...
A cold front will cross the region this evening, bringing cooler
drier air for the beginning of the week. There is a freeze potential
Monday night.
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.NEAR TERM /THROUGH TONIGHT/...
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As of 815 PM Sunday...
Surface analysis as of this evening shows that the cold front is
currently located over far western NC/VA. Most guidance suggests the
front will move through the far north/northwest Piedmont/Triad after
midnight and reach the SC/NC coast by sunrise Mon. Accordingly,
winds will shift from WSW to NW behind the front, with some brief
gusts along/behind the boundary of 15-20 mph. Temperatures were
running in the mid 60s in the north to the low 70s in the south.
Though immediately behind the front in VA/TN/KY, temperatures were
in the 50s. We should see overnight lows right around sunrise, with
the CAA ensuing overnight, in the upper 30s NW to low 50s SE.
As for precipitation chances, they look meager and highest over the
southern/eastern Sandhills to southern Coastal Plain. Regional radar
shows light to moderate rain over GA and portions central/eastern SC
tied to a mid-level shortwave. This shortwave will track ENE toward
and off the coast after midnight. Forecast soundings show very dry
air in the sub-cloud layer below 5 kft across our southern zones,
such that most activity will have a difficult time reaching the
ground. The greatest moisture transport also resides in far SE NC
and toward the coast. Nevertheless, low-end 20-30 percent chances
are still forecast over the eastern Sandhills and southern Coastal
Plain overnight, drying out by morning. A better chance of rain may
exist tomorrow with a strong upper trough moving through Mon evening.-- End Changed Discussion --
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.SHORT TERM /MONDAY AND MONDAY NIGHT/...
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As of 300 PM Sunday...
Cooler and cloudy conditions are expected Monday behind tonight`s
front...
Surface high pressure will build east from the central
Plains Monday to across the Deep South by Monday night. Partly to
mostly cloudy skies, and northwesterly wind gust to 20 mph, will
make for a more chilly day compared to recent high temperatures.
Highs in the mid-50s to low 60s will be 10 to 15 degrees lower than
Sunday, and around 5 degrees below normal.
A deep trough will dig SE across the region Monday night,
maintaining breezy northwesterly flow and cold air advection through
early Monday night. The trough may be able to tap into lingering
moisture across the southern Coastal Plain to generate a shower or
two Monday evening, then dry conditions are expected for the
remainder of the period. The cold air surging into the region Monday
night will lower temperatures to 5 to 10 degrees below normal, with
many areas dipping to near or just below freezing. The southern half
of the region has begun the growing season, and the Freeze Watch
remains in effect for the southern Piedmont and the western
Sandhills for Monday night. The remaining areas of the Sandhills and
the southern Coastal Plain may need a frost advisory.-- End Changed Discussion --
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.LONG TERM /TUESDAY THROUGH SUNDAY/...
As of 320 PM Sunday...
High pressure should be centered over Louisiana Tuesday morning and
slowly drift to the east through the week. Cold advection will
continue with westerly flow, and Tuesday should have the coldest
highs out of the next seven days, with values in the 50s. As the
Gulf Coast high shifts to the east, the wind should take on a
southerly component, allowing warmer temperatures to move into the
region. Tuesday night`s temperatures should be warmer than Monday
night`s temperatures everywhere, with lows ranging from 35 to 43, so
an additional night of frost/freeze headlines appears unlikely.
Highs should moderate nicely into the 60s and low 70s on Wednesday
before a wind shift drops highs by about 5 degrees on Thursday.
Model solutions diverge for the weekend. While both the GFS and
ECMWF (along with their respective ensembles) show a low developing
over the Gulf of Mexico, crossing Florida, and moving up the
Carolina coast, the models have shown different timing, with the GFS
faster with the arrival of precipitation than the ECMWF. Considering
the NBM timing has been closer to the GFS/GEFS timing, have gone
close to that through the extended forecast. This brings chance pops
to the forecast for Friday, Friday night, and Saturday, with the
surface low near the NC/SC border Saturday morning, and slight
chance pops for Saturday night and Sunday. Meanwhile a quick look at
the 12Z ECMWF shows the model trending quicker with the
precipitation, with timing closer to the GFS family but the low
still about 12 hours slower than the GFS. Highs through the weekend
should be near normal, mostly in the 60s, with lows in the upper 30s
and 40s.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
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As of 815 PM Sunday...
VFR conditions will prevail across central NC through the next 24
hours. An area of rain will mostly pass to our south and east
tonight, but it could skirt the Sandhills and Coastal Plain
(including FAY and RWI) with periods of light rain from about 02z to
09z. No ceiling or visibility restrictions are expected regardless.
Otherwise, a deck of mid and high clouds continues to stream over
the region, but behind a cold front that moves through this evening,
they will start to dissipate and become more scattered in nature
overnight from NW to SE. 5-10 kt winds largely from the SW will turn
NW behind the cold front overnight. They may briefly gust to 15-20
kts at times. A better chance of NW winds gusting to 15-20 kts will
occur tomorrow afternoon.
Outlook: A period of light rain can`t be ruled out tomorrow evening
as a strong upper disturbance swings through, particularly in the
south and east (including RDU, FAY and RWI). Conditions should stay
VFR. The rest of the outlook period will be dry with VFR conditions
until Friday when the next storm system brings a chance of rain.-- End Changed Discussion --
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
Freeze Watch from late Monday night through Tuesday morning
for NCZ073>076-083-084.
&&
$$
SYNOPSIS...CA
NEAR TERM...CA
SHORT TERM...JJT
LONG TERM...Green
AVIATION...Danco