767
FXUS62 KCAE 211546
AFDCAE

Area Forecast Discussion
National Weather Service Columbia SC
1146 AM EDT Sun Jul 21 2024

.SYNOPSIS...
A frontal boundary will be stationary across the region for the
next several days with increased shower and thunderstorm
activity mainly in the afternoon and evening hours. Some
locally heavy rainfall is possible which could result in areas
of flash flooding and rising river levels. Temperatures will be
near to slightly below through the middle of next week.

&&

.NEAR TERM /THROUGH TONIGHT/...
Key Message(s):

- Scattered showers and thunderstorms mainly late this evening
  into tonight.

A deepening upper trough over the Central Plains has led to an
increase in amplification of the height pattern and as a
result, some height rises over the forecast area are expected
today. A bit of drier air aloft has also moved into the area,
lowering PWATs slightly but still remaining around 1.8 to 1.9
inches. It does appear that convective chances may be a bit more
limited today, at least during the daylight hours. Strongest
surface convergence remains north and west of the area along the
front which is well into NC and along a surface trough in the
Upstate and portions of north GA. Isolated to widely scattered
showers and storms remain possible today with the relatively
moist airmass and some moderate destabilization expect this
afternoon. The higher chances for showers and potential elevated
thunderstorms likely is tonight as the upper trough continues
to push towards the area and consensus among guidance is a
shortwave will push into the area. Forecast soundings show
elevated instability remaining sufficient for thunderstorm
development and HREF mean shows PWATs rising to back over 2
inches across the entire area. This will favor efficient rain
rates, although the steering flow is likely to be strong enough
to prevent flooding issues unless significant training of storms
is observed which generally appears unlikely. Temperatures will
continue to be near to just below seasonal average with the
airmass remaining seasonably humid.

&&

.SHORT TERM /MONDAY THROUGH TUESDAY/...
Key Message(s):

- Stagnant pattern persists with a continued potential for heavy
  rainfall

A stalled frontal boundary remains over The Midlands and CSRA early
this week. In addition a weak upper level trough over the Upper
Mississippi River Valley will rotate weak disturbances in a
southwest flow aloft and enhance diurnal convective activity.
Precipitable water values in excess of two inches provides the
continued risk of flash flooding. Wet antecedent soil conditions and
storm motion speeds of 15 mph or less will add to the flooding risk.
WPC has the region in a Marginal Risk of Excessive Rainfall for the
entire service area on Monday and the Northern and Western Midlands
on Tuesday.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
Key Message(s):

- Subtle pattern change with a trend toward less rainfall and
  warmer temperatures

A persistent upper level trough over the Upper Mississippi River
Valley slowly lifts into the Great Lakes and then progresses
eastward during the latter half of the week. This should allow
high pressure aloft to build westward into the Southeast U.S.
Temperatures should gradually warm with rising H5 heights and
the chances of precipitation should decrease to climatological
norms for mid summer by the end of the forecast period.

&&

.AVIATION /16Z SUNDAY THROUGH THURSDAY/...
Ceiling Restrictions Possible at the Terminals this Morning....

Areas of low clouds continue to move across the region at
daybreak resulting in periodic IFR ceiling restrictions,
especially at the Augusta terminals. The low stratus will
scour out with scattered cumulus developing by midday. While
scattered showers and thunderstorms are possible later today,
confidence is not high enough to warrant their inclusion in the
TAFs at this time. Any convection that develops today should
diminish with the loss of daytime heating followed by increasing
cloudiness and possible ceiling restrictions once again Sunday
night.

EXTENDED AVIATION OUTLOOK...Thunderstorms likely each day and
may cause brief restrictions. Abundant low level moisture may
cause early morning restrictions through mid-week.

&&

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

&&

$$

SYNOPSIS...
NEAR TERM...
SHORT TERM...
LONG TERM...
AVIATION...