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506
FXUS62 KCAE 211506
AFDCAE

Area Forecast Discussion
National Weather Service Columbia SC
1106 AM EDT Tue May 21 2024

.SYNOPSIS...
High pressure will dominate the region through early Thursday
keeping fair and dry conditions in place along with warming
temperatures. A frontal boundary will approach the region
Thursday night and Friday and is expected to stall just north
of the area resulting in chances of showers and thunderstorms
Friday through next weekend.

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.NEAR TERM /THROUGH TONIGHT/...

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Another beautiful day expected today with plenty of sunshine
under the influence of high pressure. Surface high pressure is
centered over the Delmarva region and ridging into the
southeastern states. Aloft, an upper ridge axis extends through
the Lower Mississippi Valley into the Mid-Atlantic region
extending from a high over northern Mexico. GOES derived PWATs
are around 0.7-0.8 inches across the forecast area today and
should change very little through the day. This will result in
another beautiful day with no rain chances. Forecast soundings
show a significant amount of dry air in the atmospheric column
and a strong subsidence inversion aroun 800mb-700mb further
supporting the lack of rain chances. Temperatures should be
about a category warmer today with highs in the mid 80s with
some 87-88 degree readings possible.

Generally clear skies and light winds overnight support strong
radiational cooling. Tonight low temperatures will be similar
to this morning in the upper 50s to low 60s.
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.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
Upper level ridge will be along the I-95 corridor Wednesday
morning then slide eastward as the next upper level trough
swings into the western Great Lakes and MS River Valley region
Wednesday afternoon. At the surface high pressure will remain in
control as it reorients offshore and weak southerly flow begins
returning moisture to the area. Subsidence inversion over the
area early Wednesday will gradually erode through the day
however mid level lapse rates will remain less than 6.0 C/Km
which will again limit cumulus development and make for another
mostly to partly sunny day. Additional change will occur on
Thursday as the upper trough slides into the eastern US and
flattens the ridge while a weak surface cold front moves toward
the forecast area. Models continue to stall the front north of
the area Thursday afternoon and evening however southerly flow
will become more defined and push pwat values back to 1.4 inches
or better across the area. Although the moisture will be
increasing a trigger mechanism will still be lacking and with
mid level lapse rates only expected to be at 5.5 C/Km do not
expect any convection so have lowered pops slightly for Thursday
and Thursday night. High temperatures will be in the upper 80s
Wednesday and low 90s Thursday. Overnight lows also warming in
part due to increasing clouds with mid 60s Wednesday night and
upper 60s Thursday night.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
Frontal boundary will remain north of the area Friday as weak
upper level ridging tries to return to the eastern US. Frontal
location remains in question however appears to be along the
VA/NC border and stretching westward along the KY/TN border.
Southerly flow will continue advecting moisture into the
forecast area with pwat values between 1.5 and 1.7 inches Friday
through the weekend. Have remained with chance pops for Friday
through Sunday with the highest pops in the northern Midlands
and Pee Dee where the best chance for a passing short wave will
reside. Concern of the period shifts to Sunday night and Monday
as the potential for low pressure developing in eastern OK and
ejecting toward the Ohio Valley is increasing in likelihood.
This would push a cold front and upper level troughing through
the forecast area Monday along with increasing potential for
convection some of which could be strong. Have mid to high
chance pops for next Monday attm and will continue to monitor.
Temperatures through the long term will be slightly above normal
with highs generally in the upper 80s to low 90s.

&&

.AVIATION /15Z TUESDAY THROUGH SATURDAY/...
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High pressure at the surface and aloft along with a lack of
moisture will generally support VFR conditions through the TAF
period. Some fair weather cumulus expected through the day
before dissipating at sunset with mostl clear skies overnight.
East-northeast winds around 5 to 7 knots expected through the
day then becoming light and variable to near calm tonight.
Cannot rule out some brief vsbys restrictions in fog at prone
OGB/AGS.

EXTENDED AVIATION OUTLOOK...No significant flight restrictions
are currently anticipated through Thursday. Low probability of
restrictions during the late week period into the weekend from
afternoon and evening convection.
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&&

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

&&

$$