GSP Forecast Discussion
279
FXUS62 KGSP 262353
AFDGSP
Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
753 PM EDT Sun Jul 26 2026
.WHAT HAS CHANGED...
Updated the aviation discussion for the 00z TAF issuance.
&&
.KEY MESSAGES...
1. Severe threat remains low through Tuesday morning before
increasing Tuesday afternoon into Tuesday night ahead of a cold
front. Storms may linger into early Wednesday. A warming trend
is expected through Tuesday, with slightly cooler highs and lower
humidity returning by Wednesday behind the front.
&&
.DISCUSSION...
Key message 1: Severe threat remains low through Tuesday morning
before increasing Tuesday afternoon into Tuesday night ahead of a
cold front. Storms may linger into early Wednesday. A warming trend
is expected through Tuesday, with slightly cooler highs and lower
humidity returning by Wednesday behind the front.
Persistent upper troughing will continue over the eastern United
States while a large upper anticyclone dominates over the central
and western United States. This "Ring of Fire" pattern will allow
storm complexes to round the norther/eastern periphery of the upper
anticylcone, diving towards the GSP forecast area overnight tonight
and again tomorrow night. Confidence on these storm complexes
holding together each night/morning remains low as 06Z CAMs depict
them gradually weakening as they push farther south towards the
southern Appalachians. As a result, confidence on the severe threat
with these complexes remains low, especially overnight tonight into
early Monday morning. The SPC Day 2 Severe Weather Outlook has the
northern and western tiers of the GSP CWA in a Marginal Risk for
early Tuesday morning but again confidence low on whether activity
will hold together well enough to lead to a damaging wind threat.
Otherwise, only isolated showers and storms are expected this
afternoon and early evening with the severe risk remaining low.
Mostly dry conditions are expected Monday afternoon and evening but
cannot entirely rule out an isolated shower or thunderstorm
developing.
The severe threat ramps up Tuesday afternoon and evening ahead of a
cold front. However, confidence remains low regarding the severe
potential with this front as it will depend on how well the storm
complex Tuesday morning holds together as it tracks southward. If
the complex weakens significantly and leaves behind less debris
cloudiness, then we would have more time for the atmosphere to
destabilize during peak heating, allowing for severe storm
development. If the complex does not weaken significantly and leaves
behind more debris cloudiness, then we would have less time for the
atmosphere to destabilize during peak heating as it would take
longer for the debris cloudiness to lift. The SPC Day 3 Severe
Weather Outlook has a Slight risk in place across western NC, the
northern SC Upstate, and extreme northeast Georgia with a Marginal
risk in place across a portion of the southern SC Upstate and
portion of northeast Georgia for Tuesday. This appears reasonable as
if we are able to destabilize enough during peak heating then strong
to severe storms can be expected, especially with an abnormally high
amount of deep layer shear (30-45+ kts) in place for this time of
year. The severe threat could linger into late Tuesday night or even
early Wednesday morning but confidence is low as 06Z CAMs do not go
out far enough to capture the full event.
The cold front will stall across the Southeast Wednesday through
Friday as surface high pressure builds in behind it. This will allow
drier conditions to return for the rest of the workweek. Shower and
thunderstorm chances look to return over the weekend as the front
lifts back northward.
A warming trend is expected ahead of the front through Tuesday, with
cooler and less humid conditions returning behind the front starting
Wednesday and lingering through the rest of the period. Tuesday
still looks to be the hottest and most humid day of the week,
especially east of the mountains where heat indices could flirt with
Heat Advisory criteria (which starts at 105 degrees). However,
confidence on reaching heat advisory criteria is low as lingering
debris cloudiness could limit both afternoon temperatures and heat
indices.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
At KCLT and elsewhere: Other than a few isolated showers over the
eastern SC Upstate, the RADAR is clear across our area and all sites
are reporting VFR conditions. Other than some overnight/morning re-
strictions at our NC terminals, conditions are expected to remain
VFR thru the 00z TAF period. I kept TEMPOs in place to account for
MVFR/IFR visby and sct to bkn IFR to LIFR cigs at the NC terminals
thru daybreak Monday. Any restrictions should sct/burn off by 13z
or so. A weakening line of storms is expected to approach our area
from the north overnight and into the morning, but it still appears
that it will remain to our west and not impact any of our TAF sites.
Otherwise, shower/t-storm chances are too low to mention in the TAFs
on Monday. Winds will be mostly light and VRB to calm tonight and thru
the morning, with most terminals favoring a light, N/NW direction or a
WLY direction tomorrow aftn/evening.
Outlook: Showers and thunderstorms may impact our fcst area Tues morning
but confidence remains fairly low. Strong to severe storms and breezy SW
winds are possible Tues afternoon/evening ahead of a cold front. Storms
could linger into early Wed morning, but confidence is low at this time.
Low stratus and/or fog will be possible each morning, mainly in the mtn
valleys.
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...None.
NC...None.
SC...None.
&&
$$
AR/JPT
NWS GSP Office Area Forecast Discussion
