Area Forecast Discussion Issued by NWS Raleigh/Durham, NC
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000
FXUS62 KRAH 171921
AFDRAH
Area Forecast Discussion
National Weather Service Raleigh NC
321 PM EDT Sun Mar 17 2024
.SYNOPSIS...
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A cold front will cross the region late today, bringing cooler air
for the beginning of next week, including freeze potential Monday
night.-- End Changed Discussion --
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.NEAR TERM /TODAY THROUGH TONIGHT/...
As of 940 AM Sunday...
Update: The morning forecast update included increasing PoPs across
portions of the Sandhills and Southern Coastal plain this afternoon
and evening as the cold front sweeps across the region late tonight
early tomorrow. Otherwise forecast was on track for increased cloud
coverage through the day with light W then SW winds before the cold
front, then becoming N to NW winds after it passes. Gusts are
expected to increase late tonight immediately behind the front of 15
to 20 mph then settling down as the cold front moves offshore by mid
morning Monday. Highs today expected to be in the upper 60s NW to
low 70s SE.
As of 352 AM Sunday... Zonal flow over central NC was evident on
water vapor imagery this morning. Further north, an upper trough was
digging into the upper Midwest. Simultaneously, weak vorticity
perturbations embedded within a developing shortwave have generated
convection from central TX northeastward through AR.
At the sfc, a weak area of low pressure was located near Cape
Lookout, with a boundary extending just offshore and south through
the Gulf of Mexico. Further northeast, a 1014 mb high anchored off
Cape Cod was extending light ssely flow across central NC ahead of a
cold front draped across the Ohio Valley. Residual stratus will
quickly lift this morning, but additional mid to level cloudiness
will blanket the sky as the aforementioned shortwave over the deep
south moves through the southeast today. Highs will remain a bit
above average again today in the upper 60s to lower 70s.
A sfc low associated with the shortwave over TX this morning will
push east across the Gulf of Mexico today and scoot by just to our
south overnight. Rain chances for our area appear to be quite low
today given that 1) the deeper moisture will pool to our south and
2) the better upper and sfc forcing will remain well to our north.
Still can`t rule out a few passing showers across the Sandhills and
Coastal Plain, but overall expecting a low QPF event.
The cold front currently over the Ohio Valley will pass through our
area tonight. Swly flow ahead of the cold front may induce some
gusts of 10 to 20 mph this afternoon/evening. Additionally, good
mixing behind the front will likely support periods of nwly
gustiness with frontal passage through early Monday morning. CAA
should lag the front, allowing overnight lows to remain in the lower
50s.
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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 fore 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 --
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
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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.-- End Changed Discussion --
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
As of 210 PM Sunday...
Mid and high clouds will continue to stream across the region ahead
of the incoming cold front from the west. Widespread VFR conditions
at all TAF sites this afternoon are expected to continue through the
18z TAF period. Isolated areas of light rain across the Sandhills
later this evening and overnight could be possible therefore have
VCSH at KFAY between 5z and 12z Monday morning. Winds this
afternoon have been mainly W to NW, but expected to take a turn as
the front moves through to N to NW overnight and tomorrow.
Occasional surface gusts of 15 to 20 kts are possible this afternoon
ahead of the front then again early Monday morning as the cold front
moves out of the region.
Outlook: VFR conditions are expected through the remainder of the
outlook period.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
Freeze Watch from late Monday night through Tuesday morning
for NCZ073>076-083-084.
&&
$$
SYNOPSIS...Kren/Luchetti
NEAR TERM...CA/Luchetti
SHORT TERM...JJT
LONG TERM...Green
AVIATION...CA