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000
FXUS62 KCAE 222312
AFDCAE

Area Forecast Discussion
National Weather Service Columbia SC
712 PM EDT Mon Apr 22 2024

.SYNOPSIS...
High pressure settles in across the area for tonight and
Tuesday. A front coming through Wednesday could provide a slight
chance of light showers. Fair and cooler Thursday. Weak surface
high pressure will generally remain over, or near, our vicinity
Friday into next weekend, providing some gradual moderation in
temps.

&&

.NEAR TERM /UNTIL 7 AM TUESDAY MORNING/...
Surface high pressure continues to settle in over the area,
which has helped to bring clear skies to the region. The surface
high is expected to remain over the region overnight.
Meanwhile, the base of an upper trough has moved offshore.
Despite the trough moving offshore, heights remain on the lower
side. A combination of these factors is expected to lead to
efficient radiational cooling tonight, allowing for chilly
temperatures. A few locations could dip down to the upper 30s
(mainly in the northern portions of the forecast area),
otherwise lower 40s can be expected.

&&

.SHORT TERM /7 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/...
High pressure is forecast to continue traversing the forecast
area on Tuesday, with temperatures beginning to moderate towards
normal again. We should start the day off pretty chilly after a
night of near ideal radiational cooling conditions, but we`ll
warm into the low and mid 70s by the afternoon hours. Winds
shifting out of the southwest in the 1000-850 hPa layer will
help to increase warm advection and will lead to the temperature
moderation. Overnight, lows should be in the upper 40s. On
Wednesday, a shortwave trough is forecast by guidance to push
into the northeastern US by Wednesday night and early Thursday,
pushing a cold front towards us. Ahead of this, westerly and
southwesterly low-level flow is forecast to increase PWs to
>1.0" along and ahead of the front, especially across the
northern FA. This is where rain is most likely, as much of the
ensemble and operational suites are now indicating the potential
for light QPF in many areas ahead of the front. While the
synoptic forcing is weak, it looks like the front itself should
be enough to forecast some widely scattered showers by Wednesday
evening. LREF members have slowly increased rain chances each
run, now having 20-30% probabilities of measurable rainfall.
Thinking it is more likely than not that the rainfall stays
mainly isolated but there is a good enough chance to persist
in having a ~20% PoP in our northern counties. Temps should be
nice and warm again ahead of the front as warm advection
continues and we see some compressional heating ahead of the
front. Look for highs between 77F and 82F, with overnight lows
in the 50s.

&&

.LONG TERM /THURSDAY THROUGH MONDAY/...
High confidence in a low impact long term period. LREF members
agree with the operational guidance in showing general
troughiness enveloping the eastern CONUS by Thursday evening
behind Wednesday`s front. A relatively cool, Canadian high
pressure system is forecast to follow this into the area,
keeping us mainly dry with seasonal temps into the weekend. We
should see gradual, steady warming and moistening as we get into
late weekend/early next week. Guidance is confident and
consistent in showing rising 500 hPa heights and southeasterly
low-level flow around the low-level high pressure system. This
type of setup usually favors low rain chances and a slow warm
up, so not expecting highs to be significantly above normal
again until after this period ends. Generally dry and benign
weather is expected as well.

&&

.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
VFR expected through the period.

Strong pressure ridge across the area overnight into Tuesday.
The air mass is quite dry. Clear sky and light and variable
winds through at least 12z. The ridge will move to the coast by
18z Tuesday and winds will become south to southwest 5 to 10
knots.

EXTENDED AVIATION OUTLOOK...Restrictions possible Friday into
Saturday as moisture increases, otherwise no significant
impacts to aviation expected.

&&

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

&&

$$