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836
FXUS62 KCAE 131824
AFDCAE

Area Forecast Discussion
National Weather Service Columbia SC
224 PM EDT Mon May 13 2024

.SYNOPSIS...
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Unsettled weather will remain with some rainfall possible
through midweek. A bit drier air moves in for Thursday before
moisture returns for the weekend. Temperatures near to slightly
below average.
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&&

.NEAR TERM /THROUGH TONIGHT/...
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Current satellite and regional radar imagery showing large scale
MCS moving along the Gulf Coast this afternoon. This feature
will continue to track off to the east this evening, with a
trailing convective system them possible late tonight and
towards morning. Even that second system appears as if the main
track will remain off to the south of the cwa. So, for our area
a typical Panhandle Rob Job (PRJ) could be on tap overnight as
convection keeps the deeper moisture and rainfall further south
of our cwa. This would mean a more stable airmass and lighter
rainfall overnight as deeper moisture will be south of the
area. Models trending in that direction, and pass the best
rainfall south of the CSRA, and only have scattered showers
moving through overnight. May actually end up with a period with
little to no rain late tonight, but will still keep at least
chance pops in late. Temperatures will generally only drop into
the low to mid 60s as clouds slow the overnight drop.
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.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
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Uncertainty remains in the short term period as to the progression
of precipitation through Tuesday. A strong MCS is expected to move
to the south of the area which typically limits convective potential
for our area but recent runs of the CAMs have trended this slightly
faster which may allow for the potential for some destabilization
across the area into the afternoon with PWATs expected to be
anomalously high. It appears the most likely evolution is a round of
rain for the area associated with strong isentropic lift, with a
warm front to the south, followed by a bit of a lull in precip
chances before a strong shortwave moves through the forecast area.
This should generate numerous showers and thunderstorms during the
afternoon. The overall severe threat remains low with HREF mean
indicating around 1000 J/kg of sbCAPE across the area during the
afternoon, although deep layer shear will be sufficient to support
organized storms. As a result, we do remain in a day 2 marginal risk
from SPC mainly for the potential for isolated damaging wind gusts.
Locally heavy rain will likely be observed with any storms but they
should be moving fast enough to prevent flooding issues, unless
significant training is observed. As the upper forcing associated
with the shortwave continues moving to the northeast, precip
chances will continue to decrease overnight Tuesday.

Models remain consistent in bringing the main upper low through
the area Wednesday which even with a slight decrease in
moisture, LREF members indicate there remains a high
probability (65 to 75 percent) of PWATs remain above an inch and
a quarter, especially across the northwestern portion of the
forecast area. With pops remaining low in the morning, this
should allow moderate destabilization into the afternoon. Deep
layer shear expected to be slightly lower than Tuesday but still
should be sufficient to support at least multi-cellular
convection which with some drier and cooler air aloft, could
lead to the potential for hail or some stronger wind gusts. I-95
corridor is in a marginal risk for severe weather for now but
would not be surprised if that is expanded to include more of
the NE portion of the area.
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&&

.LONG TERM /THURSDAY THROUGH MONDAY/...
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Ensemble means remain consistent in ridging building over the
area Thursday which will lead to relatively quiet weather. Quite
a bit of uncertainty for the end of the week into the weekend
with the overall 500 mb generally supporting southwesterly flow,
although ensemble members remain split as to how amplified this
pattern will become which is leading to significant differences
in timing of the progression of shortwaves through the flow. At
the very least, moisture will be anomalously high across the
area Friday into early next week which will at least support
diurnally driven convection each day through the end of the
period. Blended guidance also supports near average temperatures
each day, which for reference this time of year, is mid-80s for
highs to low 60s for lows.
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&&

.AVIATION /18Z MONDAY THROUGH SATURDAY/...
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VFR conditions to start off the period, then lowering ceilings
through the evening and overnight through mvfr and into ifr as
moisture and light rainfall increases across the region.
Regional radar showing some light rain currently across the CSRA
and Midlands and will start off with mention of -shra with both
vfr visibilities and ceilings. Lower vfr ceilings will begin to
move in after 20z as this batch of rainfall moves east.
Confidence in any additional widespread rainfall and timing overnight
and into Tuesday is somewhat low, so will go with vcsh for the
remainder of the taf period, amending if heavier activity
develops. Ceilings after 00z expected to be dropping into mvfr
with the better low-level moisture moving in, then down into ifr
or lower after 05z tonight. Ceilings remaining ifr through 18z
Tuesday. Winds should stay up from the southeast to east through
the period, generally around 5-10 knots.

EXTENDED AVIATION OUTLOOK...Showers and thunderstorms and
associated restrictions are possible through Wednesday and
again on Friday.
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&&

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

&&

$$