Area Forecast Discussion
Issued by NWS Columbia, SC

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540
FXUS62 KCAE 271839
AFDCAE

Area Forecast Discussion
National Weather Service Columbia SC
239 PM EDT Mon May 27 2024

.SYNOPSIS...
A cold front will move through the area tonight and some scattered
strong-severe thunderstorms are expected this afternoon and
evening, mainly south of I-20. More seasonable temperatures and
drier conditions are expected behind the front through late week
as high pressure area builds in from the upper Mississippi
Valley.

&&

.NEAR TERM /THROUGH TONIGHT/...
Most of our area remains weakly capped as of 18z behind this
morning`s MCS passage, with an approaching trough aloft and
associated surface front heading in from the northwest. The
focus for convection is currently southwest of our area along
the draped boundary from that earlier MCS, but enough clearing
could allow some sufficient destabilization across the CSRA and
Midlands over the next few hours, especially with the forcing
from the approaching surface front. Confidence is relatively low
however in how far north any convection will develop given that
the HRRR and the other HREF members are consistent in
developing the vast majority of heavy convection south and east
of I-20; a severe thunderstorm watch is up for our extreme
southern tier of counties. ML CAPE across the HREF members
should climb above 2000 j/kg by this evening for much of the
area and enough mid- level flow will allow for 0-6km shear over
30 knots; combined with the dry air aloft and modest inverted V
sounding, large hail up to half dollar sized and damaging winds
are the primary threats, primarily south and east of I-20.
Convection should simmer down shortly after 01z across the area
and winds will shift out of the northwest late this evening as
the front pushes through.

&&

.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
Upper level trough will be over the eastern US through the short
term with high pressure and drier air building in behind the front.
By late afternoon pwat values are expected to fall under 1 inch and
mid level lapse rates will be 6.0 C/Km or less. Surface and low
level winds will also be westerly to northwesterly which will lend
some downsloping to the drying as well. Little change is expected on
Wednesday as high pressure continues to build into the area from the
northwest and with the northerly flow continuing slightly cooler air
will also persist over the region. High temperatures Tuesday will be
in the upper 80s to low 90s and on Wednesday the mid 80s to around
90. Overnight lows will be in the low to mid 60s Tuesday night and
the upper 50s to low 60s Wednesday night.

&&

.LONG TERM /THURSDAY THROUGH MONDAY/...
Highly amplified upper level pattern will be slow to change through
Friday then become more zonal for the weekend. The upper level
trough will gradually dig into the eastern US Thursday and early
Friday with the axis finally swinging offshore early Friday
afternoon. By Saturday the upper ridge which had been building into
the Great Lakes region will begin to get suppressed by troughing
moving into it resulting in more zonal flow by Sunday. At the
surface high pressure will be ridging into the forecast area
Thursday with the center overtaking the mid Atlantic States on
Saturday then sliding eastward into the Atlantic Basin Sunday. This
will keep drier air over the region through Friday with moisture
slowly returning to the region over the weekend with slight chance
of convection in the CSRA Saturday and the entire forecast area
Sunday. With the trough over the eastern US temperatures will be
slightly below normal.

&&

.AVIATION /19Z MONDAY THROUGH SATURDAY/...
Thunderstorms possible at AGS, DNL, and OGB this afternoon and evening.
VFR conditions expected otherwise through the TAF period.

Convection is developing across central GA along a outflow boundary
from this morning`s convection. This will likely slide slightly
north and will get fairly close to the AGS, DNL, and OGB terminals.
Confidence is still somewhat low however, so only included a VCTS
mention at those sites for now from 21z through 01z. Otherwise
gusty winds will continue this afternoon out of the southwest,
to around 25 knots. Convection will subside after 01z and winds
will turn out of the northwest late this evening, but will
weaken after sunset. Some patchy fog is possible early overnight
before drier can mix but again confidence is too low in
specifics for a TAF mention.

EXTENDED AVIATION OUTLOOK...Restrictions not expected through
the end of the week following Monday`s system.

&&

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

&&

$$