192
FXUS62 KCAE 111032
AFDCAE

Area Forecast Discussion
National Weather Service Columbia SC
632 AM EDT Sat May 11 2024

.SYNOPSIS...
High pressure keeps the area dry through the weekend and into
the beginning of next week. The high then moves offshore Monday
and increasing moisture supports daily chances for showers and
thunderstorms through the week ahead.

&&

.NEAR TERM /THROUGH TONIGHT/...
Currently, upper air analysis shows a trough has moved offshore
while satellite imagery indicates skies are clear across the
region. Surface observations show northerly winds have allowed
for drier air and cooler temps to move into the area.
Temperatures as of 6 am are in the upper 40s to mid 50s with
dew points in the upper 40s to around 50.

Today and tonight: Upper trough continues to move offshore,
putting us under a northwest flow regime. This flow aloft also
brings some cold air advection to the area. At the surface, high
pressure builds into the region. As a result, today is expected
to have fair skies with cooler than the past several days with
afternoon highs in the mid to upper 70s. Another upper trough is
expected to propagate from the Upper Midwest into the Northeast
by tonight. The base of this trough is forecast to pass just to
our north, sending a surface frontal boundary through the
southeast. Not expecting any precipitation associated with these
features based on how dry the airmass is (PWATs around 0.5"),
but we should see some cloud cover filter in this evening and
tonight. Lows are expected to be cool once again, generally in
the 50s.

&&

.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
Sunday and Sunday night: Dry weather expected to continue on
Sunday with broad northwesterly flow over the forecast area as
shortwave energy moves off the Mid-Atlantic coast. Atmosphere
remains relatively dry with PWATs around 0.5-0.7 inches and
forecast soundings showing dry deep dry layers above the surface
and in the mid levels. Expect plenty of sunshine with slightly
warmer temperatures in the lower 80s with surface high pressure
over the region. Lows Sunday night should again be near to
slightly below normal in the 50s.

Monday and Monday night: 500mb flow shifts more southwesterly
on Monday with surface high shifting offshore allowing for a
southerly flow to develop which will aid in moisture return into
the forecast area. PWATs forecast to rise significantly through
the day up to around 1.5 inches by 00z Tuesday (~120% of
normal). This increased moisture combined with increasing
isentropic lift and some possible weak shortwave energy should
lead to increasing pops late Monday through Monday night as
surface low pressure develops in the Plains and moves into the
Mississippi Valley by Tuesday morning. Temperatures on Monday
will be limited by increasing cloud cover and highs should range
from the upper 70s to lower 80s. Clouds and rain will result in
warmer overnight lows Monday night as well with lows expected
in the lower 60s.

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
Little overall change in the thinking for the extended forecast
period. LREF ensembles and operational guidance continue to
show a closed upper low over the MS Valley transitioning to an
open wave as it shifts eastward on Tuesday. Strong moisture
advection on deep southwesterly flow support PWATs rising to
around 160-180% of normal with values approaching 1.7-1.8 inches
by Tuesday afternoon. The strongest upper forcing and
isentropic lift should occur during the afternoon Tuesday and
have the highest pops during this period. There remains
uncertainty as to how much instability will be available to
support strong to severe weather but thunderstorms are expected.
There is the possibility of Gulf Coast convection impacting the
moisture transport northward into the area which could impact
the rain totals in our area.

Guidance is a bit quicker shifting convection out of the
forecast area Tuesday night but rain chances will persist into
Wednesday as the upper trough axis moves over the forecast area.
There should be break in the activity Wed night into Thursday
but another fast moving shortwave should approach the region
late Thursday into Friday bringing another round of showers and
possible thunderstorms to the region for the end of the week.
Temperatures through the week are expected to exhibit a warming
trend after Tuesday with highs generally in the 80s and lows in
the 60s.

&&

.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
VFR conditions expected through the TAF period.

High pressure over the region is providing clear skies for the
area. Skies are expected to remain mainly clear through the TAF
period, with the exception of some fair weather cumulus during
the afternoon hours today. North to northeast between 5 and 10
kts shift to more westerly after about 17z before becoming light
and variable after 00z. Dry conditions and a low level jet
should hinder any fog development overnight.

EXTENDED AVIATION OUTLOOK...Showers and thunderstorms and
associated restrictions are possible Monday through Wednesday.

&&

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

&&

$$