Area Forecast Discussion Issued by NWS Greer, SC
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000
FXUS62 KGSP 140553
AFDGSP
Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
153 AM EDT Sun Apr 14 2024
.SYNOPSIS...
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Dry high pressure will linger to our south into early next
week, allowing temperatures to warm well- above normal for
mid April. Another frontal system will approach our area by the
middle of next week, and could bring showers and thunderstorms to
the region.-- End Changed Discussion --
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.NEAR TERM /THROUGH TODAY/...
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As of 140 AM: Clear skies across the CWA under sfc/upper ridge
centered over the lower MS Valley and Gulf of Mexico. A pocket of
upper level moisture is seen on water vapor imagery upstream, in
conjunction with a minor jet streak. This still appears capable of
mountain wave cirrus, but any such clouds would develop too late
to really impact radiation. Lowered morning mins a tad based on
obs trends so far.
The sfc/upper ridge will migrate gradually eastward today. The day
will be warmer owing to higher partial thicknesses and a warmer
start than yesterday. That said, yesterday we experienced downslope
flow much of the day which allowed temps to rise to the high end
of the guidance range. More southwesterly flow today suggests
less enhancement, but abundant sunshine and initially light winds
should result in rapid warming, and maxes will be around 10 above
normal. Dewpoints may rebound a bit owing to the SW flow, but
the warming should produce deep mixing and RH still is expected
to drop into the upper 20s percent across much of the area. The
mixing appears better than many of the models would suggest,
and so have favored higher wind gusts than the usual model blend
produced. Furthermore, gradient will amplify a bit between the
migrating ridge and weak low moving thru the Midwest. In light of
the low RH and winds, there is a possibility we will end up with
Fire Danger Statements, but will make decisions after consulting
with neighboring offices.-- End Changed Discussion --
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.SHORT TERM /TONIGHT THROUGH TUESDAY/...
As of 2:25 PM EDT Saturday: The short-term fcst picks up at 00z on
Monday with long-wave upper trofing centered well to our north over
southern Quebec and broad, relatively flat upper ridging building
atop our region. A weak, embedded upper shortwave will translate over
our area late Sunday into Monday, but will likely provide little in
the way of upper support. Otherwise, upper ridging will persist over
our region thru the period as another upper trof cuts off a closed
low over the SW CONUS and lifts it NE towards the Great Lakes. At
the sfc, broad high pressure will be moving off the Southeast Coast
as the period begins. At the same time, a weak cold front associated
with the above-mentioned upper shortwave will move thru our area.
The front should not have much impact on our sensible wx other than
some brief low-end PoPs over our northernmost zones on Monday. For
the rest of the period, we can expect warming SLY to SWLY low-level
flow to persist over our area as we remain under the influence of
the Bermuda High. By the end of the period late Tuesday, a robust
low will eject from the central Plains and move another cold front
eastward and towards our region.
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.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
As of 2:15 PM EDT Saturday: The extended forecast picks up at 00z on
Wednesday with upper ridging in place over the Southeast and a robust,
closed upper low moving out of the central Plains. Over the next 24 to
36 hrs, the upper low will move up and over the upper ridge causing it
to flatten. At the same time, the low will get absorbed by a reinforcing
upper trof/closed low that dives SE out of central Canada. This system
will continue to translate SE thru the end of the period and likely be
centered somewhere over the eastern Great Lakes by the end of the period
next Saturday. At the sfc, our area will be under weak SLY low-lvl flow
and the western fringe of the Bermuda High as the period begins. Over
the next 24 hrs or so, a robust low pressure system will eject from the
Central Plains and move a fairly dry cold front thru our CWA late Wed
into Thursday. In its wake, the sfc pattern remains progressive with
another low spinning up just behind the first low and moving another,
potentially stronger cold thru our area on Friday. As for the sensible
fcst, no major changes were made. I kept PoPs in the slight to solid
chance range on Wed for the first frontal system with more widespread
chance PoPs for the second frontal system on Friday. Temperatures will
remain well-above climatology thru Friday with values cooling to near-
normal, if not below, by the end of the period next weekend.
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.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
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At KCLT and elsewhere: VFR, initially SKC. Some mountain wave cirrus
still may develop closer to daybreak with jet streak crossing the
southern Appalachians, and a very weak shortwave approaching later
in the day likely will generate patchy high altitude clouds as
well. Winds will be calm in many areas until daybreak but otherwise
varying between NW and SW. By mid-morning they should pick up from
the SW. Deep mixing is likely to produce low end gusts around the
region this afternoon. KAVL could experience some variability due
to deep SW flow, but should trend back to NW late tonight. Winds
probably won`t go calm as quickly tonight with gradient tightening
again.
Outlook: Some brief low VFR to MVFR clouds may develop Monday
and Tuesday as a result of a weak frontal zone developing to our
north. Otherwise VFR generally will persist through midweek under
high pressure regime.-- End Changed Discussion --
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.GSP WATCHES/WARNINGS/ADVISORIES...
GA...None.
NC...None.
SC...None.
&&
$$
SYNOPSIS...Wimberley
NEAR TERM...Wimberley
SHORT TERM...JPT
LONG TERM...JPT
AVIATION...Wimberley