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fxus62 kgsp 221833 

Area forecast discussion
National Weather Service Greenville-Spartanburg SC
233 PM EDT sun Sep 22 2019

dry and warm high pressure will persist over the region into Monday.
A weak cold front will cross the area from the northwest Monday
night, but with limited shower chances. Dry and warm high pressure
will return for the rest of the week and into next weekend.


Near term /through Monday/...
as of 230 pm: an upper ridge centered over the southeast will
remain in place thru tonight, with an attendant sfc high centered
just offshore. Meanwhile, a shortwave will progress thru the upper
Mississippi Valley and begin to suppress the ridge. Nevertheless
a subsidence inversion will stifle deep convection this
afternoon/evening. Tonight, good radiative conditions are expected
to lead to Mountain Valley fog and stratus once again, though mins
still look to be about a category above normal. Heights will fall
somewhat across our area on Monday, though subsidence and fairly
deep mixing will mitigate convection once again. An argument can
be made for small pops late in the day along the western slopes of
the Appalachians, however, as low-level flow veers to upslope. Max
temps will be 8 to 10 degrees above normal.


Short term /Monday night through Wednesday/...
as of 220 PM edt: very little remarkable in the sort term forecast
besides continued above-normal temperatures. A flattening upper
ridge will be in place aloft as the weakened remnants of a frontal
boundary cross the area Monday night. With little available
moisture, a few isolated showers are the only sensible weather
mentioned as the front passes. Surface high pressure will then take
over Tuesday and Wednesday, keeping the area generally dry and sunny
with temperatures 5-10 degrees above average.


Long term /Wednesday night through Sunday/...
as of 130 PM EDT sunday: the medium range picks up Wednesday night
with a generally flat upper pattern and surface high pressure in
place over the Carolinas. A frontal boundary will approach the area
on Thursday, though there seems to be little moisture associated
with it and the best forcing will remain well to our north. Model quantitative precipitation forecast
response is basically non-existent outside of the mountains, and
even there only a few showers may be able to develop.

Upper heights will rise considerably again Friday as an upper ridge
amplifies over the southeastern conus, which will keep Max temps 5-
10 degrees above average through next weekend. The tail end of the
front passing Thursday may surge back northward over the weekend,
though quantitative precipitation forecast response with it is isolated at best right in current
guidance and confined almost exclusively to the mountains. Though
models may not agree on exact placement of features, strong upper
ridging and warm temperatures are expected to continue through the
end of the current medium range early next week.


Aviation /19z Sunday through Friday/...
at kclt and elsewhere: VFR under a Dry Ridge of high pressure,
except in the mountain valleys where radiation fog/stratus is
expected to form again, with similar timing to this morning. LIFR
is forecast at kavl near daybreak. Winds will continue to be
out of the SW across the board thru tonight. However, the ridge
weakens early Monday as low pressure crosses the Great Lakes,
and this results in a northwest shift at kavl.

Outlook: patchy Mountain Valley fog will be possible each
morning for the next week. Otherwise expect VFR conditions, with
precipitation chances few and far between.

Confidence table...

18-24z 00-06z 06-12z 12-18z
kclt high 100% high 100% high 100% high 100%
kgsp high 100% high 100% high 100% high 100%
kavl high 100% high 97% high 82% high 88%
khky high 100% high 100% high 100% high 100%
kgmu high 100% high 100% high 100% high 100%
kand high 100% high 100% high 100% high 100%

The percentage reflects the number of guidance members agreeing
with the scheduled taf issuance flight rule category. Complete hourly
experimental aviation forecast consistency tables and ensemble forecasts
are available at the following link:



records for 09-26

Maximum temperature min temperature
station high low high low
------- ---------- ---------- ---------- ----------
kavl 86 1945 51 1956 67 2018 38 1943
kclt 94 1961 54 1956 72 1881 42 2001
kgsp 95 1933 56 1956 69 1972 41 1907

Records for 09-27

Maximum temperature min temperature
station high low high low
------- ---------- ---------- ---------- ----------
kavl 88 1998 54 1956 67 2018 35 1879
kclt 93 1900 55 1956 72 1881 43 1940
kgsp 93 1986 59 1956 69 1999 38 1899

Records for 09-28

Maximum temperature min temperature
station high low high low
------- ---------- ---------- ---------- ----------
kavl 89 1939 53 1957 67 1999 35 1940
kclt 93 2017 55 1957 71 1986 41 1947
kgsp 92 2017 52 1957 71 1999 39 1993


Gsp watches/warnings/advisories...



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