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000
FXUS62 KCAE 202059
AFDCAE

Area Forecast Discussion
National Weather Service Columbia SC
459 PM EDT Thu Sep 20 2018

.SYNOPSIS...
A large dome of dry high pressure will ensure fair weather
through the weekend. The high will shift to our east Sunday
through early next week, while a slow moving front approaches
and stalls. Moisture will increase in a low-level flow off the
Atlantic. Another front will move into the region midweek.
These factors will lead to increasing precipitation chances
during the period with a trend towards lower temperatures.

&&

.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
High pressure centered over the region will continue to provide
dry weather through tonight. Low temperatures tonight will
range from the mid 60s to around 70 degrees under mainly clear
skies. Most of the models are indicating at least patchy late
night fog given ample low-level moisture combined with dry air
aloft.

&&

.SHORT TERM /6 AM FRIDAY MORNING THROUGH SATURDAY NIGHT/...
A large dome of dry high pressure will continue to dominate.
This will ensure fair weather and continued above normal
temperatures. Forecast soundings continue to indicate a dry and
capped atmosphere, precluding convection for our forecast area
(FA), though gradual increases in low-level moisture may
provide some late night/early morning fog/stratus potential.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
High pressure aloft will shift to our east, while a front tries
to back door down into our region.  Models indicate possible weak
wedge to develop to our north Sunday/Monday with uncertainty as
to how far south it can develop. Clockwise flow around the
upper high to bring in an upper disturbance and associated
surface wave towards our region early to midweek, while another
front moves in around Wed/Thu. Atmospheric moisture will be on
the increase through the period, so expect increasing precipitation
chances and lower temperatures.

&&

.AVIATION /21Z THURSDAY THROUGH TUESDAY/...
Expect VFR conditions outside of late night or early morning
fog or stratus.

Surface high pressure centered over the region will provide dry
weather through the 24-hour TAF period. An easterly component
to the winds has resulted in a slight low-level moisture
increase. Fog or stratus development will be possible early in
the morning given the low-level moisture increase with dry air
aloft. The models indicate a 15- to 20-knot low-level jet but
it appears to weaken before daybreak. The restriction could be
stratus or fog. Still, moisture should be limited in the
initially very dry air mass. We leaned toward the GFS LAMP and
maintained VFR conditions except for a period of MVFR
restrictions at OGB and AGS because of the added moisture and
cooling associated with the river valleys. The MAV and MET MOS
support easterly wind less than 10 knots.

EXTENDED AVIATION OUTLOOK...An onshore flow should bring
increased low-level moisture with an increased chance of late
night and early morning stratus and fog.

&&

.HYDROLOGY...
Flooding continues at the Great Pee Dee River at Cheraw but the
river is forecast to drop below flood stage this evening.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
GA...None.
SC...None.

&&

$$
SYNOPSIS...99
NEAR TERM...99
SHORT TERM...99
LONG TERM...99
AVIATION...99
HYDROLOGY...99