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000
FXUS62 KCAE 250610
AFDCAE

Area Forecast Discussion
National Weather Service Columbia SC
210 AM EDT Mon Jun 25 2018

.SYNOPSIS...
High pressure will extend from the Atlantic westward into the
Gulf of Mexico through today. A hot westerly flow will continue
north of this ridge locally and high temperatures will be in
the mid 90s to around 100 degrees. A cold front will push into
the forecast area tonight and Tuesday bringing showers and
thunderstorms. Tuesday should be the coolest day in the past
week or so due mainly to increased cloud cover. A more
climatological pattern unfolds for the remainder of the period
with increasing moisture and ridging into the Southeast. This
pattern supports scattered diurnal thunderstorms and above
normal temperatures.

&&

.NEAR TERM /THROUGH TONIGHT/...
The main concern will be the possibility of severe thunderstorms
and localized flooding.

A surface trough will be in the forecast area today ahead of the
approaching cold front. The front is forecast to sink southward
and into the area tonight. Despite strong heating and
convergence into the surface trough, upper ridging will likely
limit thunderstorm coverage during much of today except there
may be considerable coverage in the north section late this
afternoon with moisture pooling ahead of the cold front plus an
approaching mid-level shortwave trough. The greatest coverage
may be this evening closer to the maximum of diurnal instability
and ahead of a mid-level shortwave trough and in an area of
convergence near the front. There will be a continued threat of
thunderstorms overnight with the front and upper feature in the
area. The NAM and GFS depict strong instability with surface-
based LI values -8 to -10. Forecast soundings indicate
considerable CAPE in the hail growth region. Damaging wind and
hail will be possible with the thunderstorms. Precipitable water
is forecast to be around 2 inches. High rainfall rates and
possible training near the front support a possibility of
localized flooding. We followed a guidance for the temperature
forecast. Expect peak heat index values about 105 and just below
the heat advisory criteria of 110 today.

&&

.SHORT TERM /TUESDAY THROUGH TUESDAY NIGHT/...
Some convection will likely persist through Tuesday morning,
and with the front stalled just south of the area, scattered
showers and thunderstorms will remain possible through the day.
The increased cloud cover and slightly cooler air behind the
front should make Tuesday one of the coolest days in the past
week or so, with highs only in the upper 80s to lower 90s.

&&

.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
Transitional high pressure will build into the area on Wednesday.
While diurnal convection is still possible, much drier
conditions are expected. Both the GFS and ECMWF then show
another shortwave moving through the region on Thursday, and
scattered thunderstorms will be possible. A low will develop off
the coast on Friday, as high pressure amplifies over the
eastern US. Have kept chance PoPs across the area, but the
better chance for convection will probably be across the eastern
Midlands where there will be more moisture associated with the
low. Onshore flow increases Saturday and Sunday with high
pressure centered to the north, with supports warming
temperatures and a climatological pattern of scattered afternoon
convection. Expect highs in the mid to upper 90s and lows in
the 70s.

&&

.AVIATION /06Z MONDAY THROUGH FRIDAY/...
High low-level moisture and stability in the wake of convection
may help support a period of stratus and fog during the early
morning hours especially at AGS where the most rain occurred.
Heating and mixing should dissipate any stratus and fog later in
the morning.

A surface trough will be in the forecast area today ahead of
the approaching cold front. The front is forecast to sink
southward and into the area tonight. Despite strong heating and
convergence into the surface trough, upper ridging will likely
limit thunderstorm coverage during much of today and the
thunderstorm chance was too low to include in the terminal
forecasts at this time.

The greatest coverage may be this evening closer to the maximum
of diurnal instability and ahead of a mid-level shortwave
trough and in an area of convergence near the front. We included
thunderstorms in the terminal forecasts during the 00z to 04z
time frame. There will be a continued threat of thunderstorms
overnight with the front and upper feature in the area.

The NAM and GFS depict strong instability with surface-based LI
values -8 to -10. Forecast soundings indicate considerable CAPE
in the hail growth region. Damaging wind and hail will be
possible with the thunderstorms.

EXTENDED AVIATION OUTLOOK...Restrictions possible each day in
early morning fog plus mainly afternoon and evening thunderstorms.

&&

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

&&

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