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346
FXUS62 KCAE 090106
AFDCAE

Area Forecast Discussion
National Weather Service Columbia SC
906 PM EDT Sat Jun 8 2024

.SYNOPSIS...
Dry conditions continue through tonight with the potential for
afternoon/evening showers and thunderstorms on Sunday as a cold
front approaches. The front moves through the area and stalls
along the coast early next week. This will result in scattered
showers and a few thunderstorms at times through mid-week.
Moisture may increase across the area mid to late week as a low
pressure system develops in the Gulf of Mexico. This may lead to
an increase in showers and thunderstorms. Temperatures will be
near or above normal early in the week but cooler temperatures
possible late in the week.

&&

.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
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Northwest flow aloft continues this evening as a mid-level shortwave
is passing just north of the area. This is only bringing a slight
increase in clouds along the SC/NC border with PW values too low
(around 1"-1.15") to support much else. Additional mainly high level
cloud cover should continue tonight, disrupting our cooling
potential somewhat. Overnight temperatures will be a few degrees
warmer than last night with lows generally in the mid-60s.
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&&

.SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/...
Sunday and Sunday night...Anomalously deep upper low over
southeastern Canada/New England with west-north-westerly flow
across the Carolinas into Georgia. A cold front will be
extending from the Mid Atlantic region southwest across
Tennessee by late in the day or evening. Weak Piedmont/pre
frontal trough across SC. With west-northwesterly flow across
the area ahead of the front, expect downslope and resulting
adiabatic warming. So, temperatures are expected to rise into
the mid 90s. But there are a couple of issues...1) Moisture
appears to increase through the day with precipitable water
likely increasing to greater than 1.5 inches based on ensembles.
Satellite showing considerable upstream cloudiness associated
with decaying mesoscale system over Kentucky. Additional clouds
associated with short wave troughs in northwest flow. So expect
some cloudiness especially in the afternoon 2) A few scattered
showers/thunderstorms may develop in the afternoon, after 18z
as weak short waves move southeast through the area with
strongest dynamics across the north Midlands to the Pee Dee. The
CAMS and model MOS/NBM suggest the highest pops across the
north. But can`t rule out a few showers and thunderstorms
developing in the rest of the area primarily in the evening as
the cold front drops southeast into and probably through the
area during the overnight. Some of the CAMS suggest more
coverage near and south of CAE. SPC now has the area in a
marginal risk, with models indicating strong deep layer shear,
30-40kt 0-6km. Instability weak to possibly moderate. So raised
pops above NBM guidance all areas mainly during the evening.
With increase in moisture, overnight lows expected to be a
little above normal, the drier air behind the front is likely
delayed until after daybreak Monday.

Monday and Monday night... The ensembles are indicating the
upper low over New England will be amplifying and moving south
toward the Mid Atlantic and Carolinas. A few short waves will
rotate through the base of the trough but the stronger dynamics
should stay mainly to the north across North Carolina. The
deterministic models suggest the front will be south of the
area. The ensemble suggest some uncertainty as to where the
front will be. So, kept low chance pops in the southeast
Midlands/CSRA closer to the front. Dry air filtering in from the
north so very low pops to the north but can`t rule out a
showers with additional short wave troughs moving through the
base of the longwave trough. Moisture should be limited though
especially north of CAE. Slightly cooler behind the front with
some lingering clouds. Highs near the NBM, mainly in the 80s.

&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
Uncertainty remains in the extended period. Drying expected now
Tuesday as the upper low opens up and moves off the coast. Short
wave ridging expected across the area. The front may be diffuse
near the area so with some uncertainty, can`t rule out a few
isolated showers southeast Midlands. But model trend is drier.
Another upper low will move toward the Deep South from the
southern Plains and may cut off over the Gulf of Mexico. the
ensemble guidance suggests uncertainty mid to late week as this
low possibly develops. Expect at least an increase in some
moisture across the region especially late week into next
weekend. The models differ on any surface low development and
placement but overall the upper low is expected to retrograde to
the western Gulf late in the period. Temperatures may be cooler
but the NBM is near normal values. Uncertainty with pops but
the NBM has generally scattered showers through the extended
period, more likely diurnally driven at this point.

&&

.AVIATION /01Z SUNDAY THROUGH THURSDAY/...
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VFR conditions expected through the end of the period.

Clear skies expected overnight with light winds at all sites
through Sunday morning. Winds will shift out of the west-
southwest by late Sunday morning, gusting to 18-20 knots
throughout the afternoon. Some showers and thunderstorms are
possible very late in the TAF period, generally after 22z, and
mainly at CAE and CUB; confidence is far too low for a TAF
mention yet.


EXTENDED AVIATION OUTLOOK... Throughout next week, increasing
moisture could produce early morning low stratus and/or fog in
addition to afternoon/evening showers and thunderstorms,
potentially causing in brief restrictions at the terminals.
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&&

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

&&

$$