Area Forecast Discussion
Issued by NWS Columbia, SC

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820
FXUS62 KCAE 131028
AFDCAE

Area Forecast Discussion
National Weather Service Columbia SC
628 AM EDT Sun Jul 13 2025

.SYNOPSIS...
Hot temperatures are expected to start off the week with weak
upper ridging in place. The ridge then breaks down, leading to
cooler temperatures and higher rain chances during the mid-week
period. A new upper ridge could build in from the east to end
the week with slowly warming temperatures.

&&

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

- Very hot and humid with scattered strong in the afternoon &
evening.

Weak and broad ridging aloft will continue to build across the
Southeast throughout Sunday, with the ridge just upstream of our
area. As a result, flow low-deep level flow will shift more westerly-
northwesterly on Sunday, but with a very widespread deep moist
airmass, northwesterly flow will not do much to drop PWAT`s. Still
expected 1.8-2.0" PWAT`s across the area with surface dews points in
the 70`s. Like we have seen the last few days, this moisture and
plenty of heating will still allow plenty of instability to develop
this afternoon; HREF broadly produces 1800-2200 j/kg of ML CAPE by
mid-afternoon. There is not any sort of capping aloft despite the
subtle ridging, so convection should steadily develop throughout the
afternoon as we hit convective temps. Severe thunderstorm threat
looks limited with marginal DCAPE, but a few spots of strong-
damaging winds are expected, like we have seen the last few days.

Besides the convection this afternoon, the heat will notable. Heat
indices should climb to around 105F this afternoon with high temps
in the mid 90`s and dew points in the mid 70`s. The warmest temps
and dews will remain south of I-20 and towards the coastal plain,
where any subtle downsloping flow will not mix out to. Its somewhat
close to Heat Advisory criteria in spots, but not expected to reach
108F, let alone for two hours.

&&

.SHORT TERM /MONDAY THROUGH MONDAY NIGHT/...
Key message(s):

- Hot and humid Monday with heat index values near advisory
  criteria, especially in the CSRA.

- Isolated to scattered afternoon and evening convection, most
  likely in the eastern Midlands.

Upper ridging breaks down on Monday due to the combination of a
passing trough to our north and an upper low to the south.
Its influence should result in another hot and humid day across
the forecast area with forecast heat indices between 100 and
105 in the Midlands and 103 and 108 in the CSRA. Will need to
monitor trends to see if a Heat Advisory will be required for
the CSRA. Regardless, typical heat precautions should continue
to be taken when working outside during peak heating. The ample
moisture should produce isolated to scattered showers and
thunderstorms, especially in the eastern Midlands as the sea
breeze boundary moves inland. As is the case during summertime
pulse convection, any thunderstorm that develops has the
potential to become strong to marginally severe producing
damaging winds in addition to small hail, frequent lightning,
and heavy rainfall.

&&

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

- Seasonal temperatures with scattered showers and thunderstorms
  possible each day.

Upper ridge fully breaks down during the mid-week period,
resulting in more typical temperatures for mid-July. The Bermuda
high will continue to advect a warm, moist air mass from the
Gulf into our forecast area with high PWAT values through the
extended. Guidance suggests that rain chances will be highest on
Wednesday when a weakening cold front may try to enter the
region. Beyond this, there may be tropical development in the
northern Gulf, but current guidance suggests it will move west
as a new upper ridge builds into the Southeastern US from the
east. This could cause temperatures to gradually rise, though
daily scattered showers and thunderstorms remain in the forecast
for the entirety of the long term.

&&

.AVIATION /10Z SUNDAY THROUGH THURSDAY/...
Some low confidence morning stratus-fog possible around sunrise.
Scattered storms likely again in the afternoon and evening.

Stratus and fog has not materialized as of 10z this morning
thanks to some lingering mid-level clouds. We could see some
brief sunrise surprise fog-stratus through 13z with some MIFG,
so only included a VFR tempo to reflect that. Otherwise light
winds, 5-8 knots, will turn out of the northwest for the
afternoon with typical summer cu developing through the early
afternoon. Scattered storms are again expected this afternoon
and evening, with a prob30 mention covering this period.

EXTENDED AVIATION OUTLOOK...There is the possibility of diurnally
driven showers and thunderstorms into early next week with the
potential for periodic restrictions.

&&

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

&&

$$

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