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Area forecast discussion 
National Weather Service Greenville-Spartanburg SC
248 PM EDT Fri Oct 28 2016

a weak warm front will pass across and then north of our area
tonight with a warming trend over the weekend. Another weak cold
front will reach our region to start the week but above normal
temperatures are expected through the middle of next week.


Near term /through Saturday/...
as of 220 PM friday: heights rise tonight and Saturday as an upper
ridge builds over the southeastern Continental U.S.. at the surface, the center
of high pressure settles in over the area tonight and slides to the
coast on Saturday. This will lead to light north to NE wind this
afternoon becoming calm or light east overnight. With only some thin
cirrus moving over the area, expect good radiational conditions.
Have gone a couple of degrees cooler than the guidance blend in
response, around 5 degrees above normal. The lower levels of the
atmosphere remain relatively moist tonight. The combination of
cooling temps and moist low levels shows up as a good fog signature
in the forecast soundings. Therefore, have included patchy fog over
most of the area. Patchy dense fog is expected in the mountain
valleys, and will be possible near bodies of water outside of the
mountains. Nearly full sun, after the fog Burns off, and rising
thicknesses will lead to highs 10 to 15 degrees above normal,
putting records in jeopardy.


Short term /Saturday night through Monday/...
at 2 PM friday: on Saturday evening a low amplitude upper rdige will
extend from The Rockies to the East Coast. The ridge amplifies over
the Great Plains on Sunday, wiht low amplitude troughing resulting
along the East Coast. By Monday the ridge progresses to the esatern

At the surface, on Saturday evening a surface ridge will extend from
the Carolina coast to the southern Appalachians. Although the ridge
persists into Sunday, a surface trough sets up along the eastern
Seaboard. A surface frotn drops soputh across our area on Monday,
but with little moisture or instability to support convection or
precipitaiton. Temperaures will run well above normal.


Long term /Monday night through Friday/...
as of 245 PM friday: Tuesday through Wednesday night, the center of
a 500 mb ridge will remain centered near the Georgia/Florida line. At the sfc, an
old front should linger generally north of the cwa, with weak sfc
high pressure across the east facing slopes of the mtns. This
pattern should favor warm and dry conditions. In fact, high should
range within 5 degrees of record highs both Tuesday and Wednesday.

Thursday into Friday, model difference begin to increase with the
placement and timing of the primary features. The GFS has a much
stronger ridge across the East Coast, yielding a slower approach of
mid level short wave and cold front. The European model (ecmwf) has a weaker ridge over the
southeast and quickly tracks a positively tilted trough across the
mid west and Appalachians. The European model (ecmwf) indicates a northwest to southeast passage of
the cold front late Thursday into Friday, with a 500 mb low closing off
over the upper Savannah River valley. Given the long string of dry
days, I will keep pops and quantitative precipitation forecast limited with the passage of this
feature. Pops will range from chance to schc across the region,
favoring the mtns for showers. Temps on Friday are forecast to range
close to normals.


Aviation /19z Friday through Wednesday/...
at kclt and elsewhere: winds turning north to NE as high pressure builds
south into the area. Expect winds to become light and turn NE to southeast
this evening with mainly few cirrus clouds. As the center of high
pressure settles in over the area, clear skies and light winds are
expected. Forecast soundings look good for fog across the area. Even
so, chances are least at kclt and kgmu and have been left out for
now. Best chance for IFR is kavl with vlifr possible. After the fog
Burns off Saturday, light S to SW winds with clear skies expected.

Outlook: dry high pressure remains through Sunday. Another dry front
will push through on Monday, with high pressure returning through
mid week.

Confidence table...

18-24z 00-06z 06-12z 12-18z
kclt high 100% high 100% high 100% high 94%
kgsp high 100% high 100% high 100% high 100%
kavl high 100% high 100% low 59% Med 63%
khky high 100% high 100% high 100% high 97%
kgmu high 100% high 100% high 100% high 100%
kand high 100% high 100% high 97% high 97%

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 10-29

Maximum temperature min temperature
station high low high low
------- ---------- ---------- ---------- ----------
kavl 79 1946 32 1910 59 1984 21 1976
kclt 82 1984 48 1925 67 1984 27 2001
1927 1910 1976
kgsp 84 1927 47 1925 66 1984 25 1976

Records for 10-30

Maximum temperature min temperature
station high low high low
------- ---------- ---------- ---------- ----------
kavl 81 1946 36 1925 58 1996 20 1910
1922 1896
kclt 84 1996 42 1925 66 1918 26 1965
1961 1881 1952
kgsp 83 1950 42 1925 65 2004 25 1910

Records for 10-31

Maximum temperature min temperature
station high low high low
------- ---------- ---------- ---------- ----------
kavl 79 2004 37 1890 63 1971 23 1917
kclt 85 1961 44 1895 67 1971 29 2008
1950 1887
kgsp 84 1950 46 1925 66 1971 25 1893


Gsp watches/warnings/advisories...


near term...rwh
short term...jat
long term...Ned

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