Area Forecast Discussion
Issued by NWS Greer, SC

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FXUS62 KGSP 301445

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
1045 AM EDT Fri Sep 30 2016

Dry southwest flow will linger across the region through this
weekend. Progressively warmer temperatures are on tap through early
next week. The path of tropical cyclone Matthew will be closely
watched as it tracks north near the Atlantic coast next week.


As of 1025 AM EDT, drier dewpoints behind the slowly passing
cold/occluded fronts have wrapped NE into the southern NC foothills
and are approaching the Charlotte area. Anticipate quick scattering
of any lingering low clouds through Noon and then little more than
limited cumulus across the ridgetops closer to the cooler
temperatures aloft this afternoon. A few models depict isolated
ridgetop convection, but profiles do not appear especially favorable
so will cap all mountain PoP at 14 percent. Temperatures were
adjusted slightly warming in central parts of the CWFA where
insolation started quickly but cooler thicknesses haven`t
sufficiently spilled in.

Otherwise, the frontal boundary should slide east of the forecast
area this afternoon and continue to spread much drier air into the
NC Piedmont and northern foothills through tonight. With the dry air
mass in place, all areas are expected to see temperatures near to
slightly below climo overnight.


At 240 AM Friday: GFS and ECMWF indicate that the center of a H5
closed low will lift north across the Great Lakes region this weekend. The
mid level pattern across the region will likely feature a Bermuda
High and a trof from the Ohio River valley south to the Mississippi
Delta. Short range guidance shows that a dry slot associated with
the Great Lakes low will rotate across the western Carolinas. This
pattern should result in dry conditions and high temperatures
ranging from the mid 70s within the mtn valleys to the low 80s east.

On Monday, it appears that an asymmetrical mid-level omega block
will develop over the northern CONUS, with the ridge axis over the
Mid West and Great Lakes. TC Matthew is expected to be tracking
north near the eastern tip of Cuba by late Monday. Sensible weather
across the CWA will remain unchanged from the dry weekend. High
temperature are forecast to warm a degree or two over values reached
on Sunday.


As of 250 AM Friday: The path of TC Matthew will gain most of the
attention through the extended period. Both the GFS and ECMWF
indicate that Matthew will track north, tracking parallel along the
Atlantic coast from FL to NC. To the west, the northern tip of a H5
ridge will reach the southern Appalachians, sourced from a high over
Mexico. To the north, another deep low is expected to organize
across the nrn plains. The pattern does not appear to be supportive
of heavy rainfall across the CWA, developing ahead or west of
Matthews track. I will keep the forecast generally dry from Tuesday
through Thursday. Temperatures are forecast to remain between 3 to 5
degrees above normal.


At KCLT and KHKY, drier air is starting to wrap in from the
southwest with no further low restrictions expected. The passing
surface cold/occluded fronts will move east of the region through
early afternoon and keep conditions dry today. Expect light S to SE
winds early to toggle more southwesterly with time. A few low end
gusts are possible at KCLT with mixing but will not be mentioned.

Elsewhere: With drier air lingering behind frontal boundary, all
sites are forecast to see VFR conditions persist for the next 24

Outlook: VFR conditions expected in most places through the
beginning of next week as dry high pressure settles in over the area.

Confidence Table...

            14-20Z        20-02Z        02-08Z        08-12Z
KCLT       High  98%     High 100%     High 100%     High 100%
KGSP       High 100%     High 100%     High 100%     High 100%
KAVL       High 100%     High 100%     High 100%     High  91%
KHKY       Med   76%     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:




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