121
FXUS62 KCAE 281842
AFDCAE

Area Forecast Discussion
National Weather Service Columbia SC
242 PM EDT Fri Jun 28 2024

.SYNOPSIS...
Hot and humid conditions continue into the weekend. Afternoon
and evening rain and storm chances increase through the weekend
with noticeably higher moisture building into the region. A cold
front is expected to bring slightly cooler and drier conditions
to start off the work week, but building high pressure will
allow the return of temperatures near the century mark by mid-
week.

&&

.NEAR TERM /THROUGH TONIGHT/...
KEY MESSAGES:
- Muggy and hot conditions developing with highs in the 90`s and
  dew points in the mid 70`s.
- Additional scattered thunderstorms develop during the
  afternoon, especially in the CSRA.

Deep moisture continues to pool across the area with PWAT`s
rising to around 2" today as ridging builds aloft. Widespread
cumulus will develop this afternoon with some pop up showers and
thunderstorms likely, again mainly south and east of I-20.
Instability is expected to remain fairly weak based on recent
obs and HREF guidance, only climbing to around 500-700 ML CAPE
by 21z. But as seen in the water vapor imagery, some noticeable
mid level dry air is present, which could help increase the
downburst potential thanks to the steep surface to mid-level
theta-e difference. So much like the last 4-5 days, an isolated
severe thunderstorm is possible but not expected to be
widespread.


&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
Key messages:
- Excessive heat concerns continue this weekend with headlines
  likely on Sunday. Additional rainfall likely.

Little change in the forecast for Saturday as the remains of the
diffuse frontal boundary remain across the area. Pwat values
will remain above 2 inches with moderate instability so expect
scattered showers and thunderstorms during the afternoon and
evening hours. With some dry air in the mid levels DCAPE values
will be 5-600 J/Kg so there is some potential for wind gusts
from the stronger thunderstorms.

On Sunday the pattern will change as a frontal boundary moves
into the area with the upper level trough also swinging into the
region. Although the best dynamics will remain north of the
forecast area there will be plenty of instability for the front
to interact with which is expected to create thunderstorms
across much of the forecast area Sunday afternoon into the early
overnight hours. The drier air in the mid levels from Saturday
will have eroded however instability will be greater and pwat
values will be nearing 2.5 inches. As such the potential for
severe thunderstorms appears low however with weak steering flow
aloft there will be increasing potential for locally heavy
rainfall.

Afternoon high temperatures will be in the low to mid 90s
Saturday with heat index values between 102 and 107 with the
highest reading in the eastern Midlands where a heat advisory
may be needed. On Sunday high temperatures will be in the mid
to upper 90s with heat index reaching 105-110. A heat advisory
is likely on Sunday with the possibility of an excessive heat
warning.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
Key Messages:

- Near normal temperatures Monday and Tuesday with the heat
  returning by the Fourth of July.

The frontal boundary is expected to be just southeast of the
forecast area Monday however with the boundary becoming
increasingly diffuse expect another round of afternoon and
evening showers and thunderstorms. Little change Tuesday as the
remains of the boundary continue to become more diffuse and
continue slowly sagging southward. With the boundary just south
of the area temperatures will be slightly cooler with highs
generally in the upper 80s to low 90s. Wednesday and Thursday
will see the return of the upper level ridge and with plenty of
moisture remaining over the region the summertime chances of
showers and thunderstorms will continue each day.
The heat on Thursday will be the main concern as temperatures
once again will push into the mid 90s to around 100 with the
heat index again between 105 and 110.

&&

.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
VFR conditions likely this afternoon and evening, outside of
some showers-storms at AGS and DNL. Stratus-fog likely Saturday
morning.

Widespread cumulus developing across the area this afternoon,
generally low based around 3k feet. Some showers and
thunderstorms are moving into the AGS and DNL area, with some
impacts possible. Timing and coverage confidence is a bit low
however so went with a VCTS through 21z at those sites.
Additional shra and tsra possible at all sites this afternoon
and evening. Winds will remain relatively light, out of the
southeast, with gusts 10-12 mph. Stratus and fog are possible
again Saturday morning for all sites starting after 09z.

EXTENDED AVIATION OUTLOOK...Scattered showers-storms with
restrictions each afternoon into early next week as additional
moisture moves over the region. Early morning fog-stratus
likely each as well.

&&

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

&&

$$