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Area forecast discussion 
National Weather Service Columbia SC
452 PM EDT Tue Oct 25 2016

seasonably cool and dry air expected Wednesday as high pressure
remains across the area. A weak front, with limited moisture, will
traverse the forecast area late Thursday/early Friday, with fair
and mild conditions expected Friday afternoon into the weekend. A
dry cold front moving through late Sunday is expected to provide
dry conditions with seasonal temperatures early next week.


Near term /until 6 am Wednesday morning/...
high pressure will extend from the Ohio Valley southeast across
the Carolinas and Georgia through tonight. The air mass is cool
and dry. The models suggest a weak pressure gradient will remain
mainly across the southeast midlands and csra. A low-level jet
overnight appears weaker than the previous night but still 15 to
20 knots around 1000 ft. More likely to decouple north of cae so
lower temperatures have been forecast in the north midlands where
net radiational cooling will likely be strongest near the ridge
axis. Forecasted overnight lows near or slightly below the MOS
consensus. Patchy frost possible in some outlying protected areas
where temperatures may fall into the mid to upper 30s.


Short term /6 am Wednesday morning through Friday/...
fair and dry Wednesday with near normal Max temps expected as
surface high axis over the area weakens and pulls east Wed/Wed
night ahead of the next approaching system. Some increasing
cloudiness ahead of the next system expected to provide min temps
late Wed nt/early Thursday morning not as cool. Upper ridge over
The Rockies, with upper troughiness over the east Continental U.S. Thu/Fri. A
pair of upper impulses, with an accompanying surface boundary,
expected to slowly move through the forecast area late Thursday
into early Friday. Best upper dynamics to remain to our north,
with relatively limited moisture for the system to work with, as
precipitable water values only recover to around or just over one
inch. A blend of model guidance generally suggests primarily
slight chance pops, favored towards the north/NE forecast area mainly
late Thu/Thu nt.


Long term /Friday night through Tuesday/...
behind the front, surface high pressure will shift into the
region late Friday into the weekend. Upper trough over the east Continental U.S.
Will lift to the north some Fri thru sun, with upper ridge center
shifting east along the Gulf Coast, providing a continued dry west-northwest
to northwest flow aloft for our area. Latest GFS appears to indicate a
dry front moving through the area late Sunday/early Monday. High
pressure center to build into the eastern Seaboard, and also
indicate a building upper ridge over the southeast Continental U.S. Mon/Tue,
appearing to ensure dry conditions. Temperatures generally at or
above climatology through the extended period.


Aviation /21z Tuesday through Sunday/...
very high confidence for VFR conditions through the period.
Clear with northeast to east winds near 10 knots this afternoon
becoming light during the evening.

Overnight, light and variable winds generally expected. However
there may be periods of east/NE winds with speeds less then 5 knots.
Dry low levels will prevent fog formation. Models indicate a
weaker low level jet overnight tonight so threat for low level wind shear is lower.

Wednesday, the surface high in the northeast will continue to
ridge into the region. Mid-level high pressure and a dry airmass
will continue the dry forecast. Expect light easterly flow
throughout the day.

Extended aviation outlook...restrictions possible Thursday and
Thursday night as a weak cold front crosses the region.


Cae watches/warnings/advisories...



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