426
FXUS62 KCAE 031029
AFDCAE

Area Forecast Discussion
National Weather Service Columbia SC
629 AM EDT Wed Jul 3 2024

.SYNOPSIS...
Moisture increases through the week and into the weekend with
isolated to widely scattered convection possible each afternoon.
Ridging builds into the area late this week and into the
weekend resulting in above normal temperatures and Heat Index
values near 110 possible.

&&

.NEAR TERM /THROUGH TONIGHT/...
Key Message(s):
- Increasing temperatures today

Ridging continues to set over top of the region this morning and
is helping to keep things quiet across the region today. Surface
high pressure has shifted eastward, allowing the surface ridge
axis to shift a bit. Southeasterly flow has commenced as a
result, which has slowly allowed dewpoints to creep back up
into the upper 60s and lower 70s most places. Despite this, PWs
remain seasonally low across the region which should allow for
at least once more day of bearable afternoon humidity. However,
temps should warm quite a bit. Not expecting upper 90s quite yet
today as HREF mean 850 hPa temps are ~16-18C, which would yield
low to mid 90s for most this afternoon. Given subsidence aloft
with the ridge overhead, not expecting any precip this
afternoon. Given rise in dewpoints, overnight lows tonight
should only fall into the low 70s across the FA.

&&

.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
Key Message(s):
- Temperatures pushing 100 degrees by Friday
- Low level moisture increasing through Friday
- Heat Index values up to 105-100 possible Thu/Fri afternoon

Thursday and Thursday night: Upper ridge remains positioned
over the deep south and southeastern states on Thursday while
surface high pressure will be off the coast allowing for a warm
southerly flow to return. This will support higher dewpoints and
therefore higher heat index values with values as high as 105
degrees possible. Forecast soundings show a capping inversion
around 700mb which will limit convection along with no real
upper forcing mechanisms but temperatures under the upper ridge
will be pushing back into the mid and upper 90s. PWAT values
will begin rising again to around normal with ensemble mean
forecast values around 1.8 inches. Cannot rule out isolated
convection but severe storm threat seems low given generally
weak instability and plenty of mid level dry air that could
entrain into any storms that develop.

Friday and Friday night: Upper ridge holds strong on Friday
despite a deepening upper low moving into the Great Lakes
region. Continued low level southerly flow should support
increasing low level moisture advection as ensemble mean PWATs
are forecast to rise to around 1.9-2.0 inches. Temperatures
should warm further with highs in the upper 90s to around 100
degrees. Dewpoints in the 70s should support heat index values
approaching or exceeding heat advisory criteria (108 degrees).
The capping inversion around 700mb is still present on forecast
soundings but a bit weaker and with temperatures pushing 100
degrees think isolated to scattered convection will be
possible. Again, instability is not forecast to be very strong
but if moisture is a bit higher than forecast that could result
in higher instability and a possible low pulse severe threat.
Not much relief at night expected with warm overnight lows in
the 70s.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
Key Message(s):
- Heat Advisory Criteria possible this weekend
- Thunderstorm chances increase this weekend into next week

An upper trough is expected to move through the Great Lakes
region Friday and into northern New England on Saturday but
does not appear strong enough to break the upper ridge over the
southeast states. However, the trough should push a frontal
boundary near the area with significant moisture pooling just
ahead of it over our forecast area with LREF ensemble showing
probabilities of PWATs greater than 2 inches at 60-80%. Despite
the increasing moisture the presence of the upper ridge may
limit widespread convection, but we should see some chances of
rain each day through the extended with the highest pops Sat/Sun
with the weak frontal boundary in the vicinity before it
becomes diffuse early next week. Widespread severe weather is
not expected but cannot rule out isolated pulse severe storms
and the above normal moisture should provide an increased local
heavy rain threat as well.

Hot and humid conditions expected Saturday with highs around
100 degrees and heat indices approaching 110 degrees. Increased
cloud cover and convection should help limit high temperatures
Sunday into early next week.

&&

.AVIATION /08Z WEDNESDAY THROUGH SUNDAY/...
VFR conditions expected to dominate the period.

Quiet TAF period is expected overall today as high pressure
dominates the region. Stratus did not form near the Augusta
sites last night, so nothing of note to mention in the immediate
term with respect to restrictions. Mostly clear skies will take
us through most of the day with generally easterly winds
between 5 and 10 knots expected. Some stratus is being shown by
guidance towards the end of the period tonight, so hedged in
that direction without explicitly forecasting restrictions in
the TAF at this time.

EXTENDED AVIATION OUTLOOK...Moisture and potential for afternoon
showers and thunderstorms and associated restrictions returns
Thursday through Sunday.

&&

.FIRE WEATHER...
Key messages(s):
-Increased Fire Danger mid to late week.
-Rainfall probabilities remain relatively low mid week.

Increased fire danger during the Independence Day Holiday week,
especially late week as temperatures rise again to well above
normal values. Scattered afternoon and evening thunderstorms
possibly may aid current dry conditions.

&&

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

&&

$$