Area Forecast Discussion Issued by NWS Columbia, SC
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000
FXUS62 KCAE 090808
AFDCAE
Area Forecast Discussion
National Weather Service Columbia SC
408 AM EDT Fri Jun 9 2023
.SYNOPSIS...
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Dry air and high pressure will remain in control of the pattern
through late Saturday night. Near to slightly below average
temps are expected along no chance for rain until Sunday,
when moisture rapidly returns to the area. A fairly active is
then expected to remain in place from Sunday onwards, with
diurnal showers and storms expected each day.-- End Changed Discussion --
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.NEAR TERM /THROUGH TONIGHT/...
IR satellite imagery shows mid level clouds across portions of
the forecast area with temperatures mainly in the upper 50s to
mid 60s. Through the remainder of the night expect little change
with the mid level clouds remaining through daybreak and with
drier air beginning to filter into the northern and central
Midlands overnight lows will generally be in the mid 50s to low
60s.
Weak cold front across south central GA and far southern SC will
continue moving southward today. This will allow light NNE winds
this morning which will back to NW this afternoon to advect
drier air into the area. Skies this morning will be partly to
mostly cloudy then become mostly sunny during the late morning
and early afternoon as the drier air overtakes the area.
Although there will be plenty of sunshine with the northerly
winds there will be a touch of cooler air moving into the region
as well which will keep afternoon high temperatures in the low
to mid 80s. Little change in the synoptic situation overnight
will keep the drier air in place and with mostly clear skies and
winds becoming light and variable with sunset radiational
cooling conditions will be excellent. This will allow lows
tonight to fall into the mid 50s to around 60.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
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The trough over the Northeast CONUS will finally shift east by
Saturday, dropping our persistent northwest flow aloft and
allowing more zonal mid level flow and weak ridging to develop.
As the surface high pressure slides off the coast to our east,
southerly component winds will steadily develop throughout the
day at low levels. Moisture however will not really make it back
into the region until late Saturday night, so mostly clear skies
will allow temps to warm into the upper 80`s.
Overnight Saturday into Sunday, moisture will rapidly begin to
fill back in aloft and near the surface as PWAT`s jump from near
0.5" to over 1.25" by Sunday morning, and surface dew points
climb into the upper 60`s. A split flow mid and upper-level
pattern (digging trough towards the Great Lakes and a somewhat
zonal southern stream) is progged to develop by Sunday over the
central US, which will then set things up for the rest of the
week. The first shortwave swinging through the southern stream
should act a trigger for some showers and storms Sunday
afternoon as sufficient moisture will be in place. However,
mediocre mid- level lapse rates will limit instability
particularly across the Midlands and Pee Dee. While there
remains a wide range of solutions across guidance still, the
CSRA consistently is able to muster 1000+ J/kg CAPE by Sunday
afternoon, so confidence is highest there in the shower-storm
potential. Shear will essentially be non-existent so any severe
threat will be pulse in nature; a modest inverted V style
profile is consistent across most forecast soundings, so a few
strong to severe wind gusts are possible with storms that
develop. High temps on Sunday again to should reach into the
upper 80`s or around 90, but precip chances have this a bit more
variable.-- End Changed Discussion --
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.LONG TERM /MONDAY THROUGH THURSDAY/...
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There is very good agreement in the trough digging into the
Great Lakes deepening by Monday, pushing a front down into the
Ohio Valley and then into the Southeast. With some further
height falls aloft, additional moisture return, and a coherent
forcing mechanism, showers and storms again expected Monday;
instability is progged to be substantially higher than Sunday in
the GEFS members so the severe threat is a bit higher. This
trough and front will then effectively stall to our north for
much of the week, allowing above average moisture and below
average heights to linger across the area. Thus, instability
looks to be available each with some diurnal heating so
afternoon and evening storms are likely each day. The CSU
severe probs are quite bullish most days next week for strong-
severe storm potential lining up nicely with environment fields
in the NAEFS; consistent shortwaves and triggers moving through,
robust moisture, some modest shear (for June), and steeper mid-
level lapse rates.-- End Changed Discussion --
&&
.AVIATION /08Z FRIDAY THROUGH TUESDAY/...
VFR Conditions expected through the TAF period with some early
morning fog at AGS.
Mid level clouds remain across the terminals with some fog at
AGS. With the mid level clouds having just moved into AGS/DNL
expect the fog to diminish over the next couple hours returning
to VFR by 09z. Through the period a weak cold front south of the
area will continue moving further south with drier air moving
into the area. This will keep scattered mid level clouds over
the area with VFR conditions. Winds will remain light and
variable through mid morning then become NNE around 5 knots
finally backing to NW around 5 knots through the end of the
period.
EXTENDED AVIATION OUTLOOK...No significant restrictions expected
through Saturday night. Periodic restrictions possible in
showers and thunderstorms Sunday through Monday night as a weak
system moves through the region.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
GA...None.
SC...None.
&&
$$
SYNOPSIS...
NEAR TERM...
SHORT TERM...
LONG TERM...
AVIATION...