Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Columbia SC
1152 PM EDT sun Jul 24 2016
high pressure along with scattered afternoon and evening showers
and thunderstorms will remain over the region through much of the
week along with above normal temperatures. Late in the week and
into next weekend an upper level trough will move into the eastern
US with a surface front approaching the area.
Near term /until 6 am Monday morning/...
with upper level high pressure over the region, a stable nocturnal
layer and lack of forcing mechanism convection is not expect
overnight. Scattered mid and high level clouds will continue to
move over the area from the east. With a low level jet around 25
knots developing overnight the potential for fog will be low.
Overnight lows will generally be in the mid 70s.
Short term /6 am Monday morning through Tuesday night/...
the mid/upper level heights will remain strong across the area as
the ridge begins to split with one centered off the southeast
coast and the other across the western U.S.. by Monday and
Tuesday...a trough will cross the Great Lakes region. The
associated surface front will remain well to the north of the
region as both GFS/European model (ecmwf) show it across VA. Boundary layer/800 mb
temps during the afternoon remain nearly the same both Monday and
Tuesday as this afternoon. So therefore do not expect much change
in temperatures with most areas reaching the mid/upper 90s through
the period. Heat index values will be near 105 degrees. As for
pops...most of the high resolution models do not indicate much in
the way of forcing as most of the S/W activity will stay north of
the area. Precipitable water values will once again be around 2.0 inches and only
expect isolated/widely scattered convection each afternoon.
Long term /Wednesday through Sunday/...
both GFS/European model (ecmwf) indicate that the mid/upper level ridge of high
pressure centered along the southeast coast will remain there
through the end of the week. By the weekend...a much strong S/W
will begin to move across the Midwest/Great Lakes region. At this
time...the ridge will begin to move eastward and heights begin to
fall over the area over the weekend. Models have had a hard time
with strength and speed of system and confidence remains low that
pops will increase late and temps will cool somewhat. Have
continued with slight chance/low chance pops from mid/late week
then increased them slightly over the weekend. Expect above
normal temperatures through the period but could see a slight
decline by the weekend. Expect highs in the mid/upper 90s with
overnight lows in the low/mid 70s.
Aviation /04z Monday through Friday/...
VFR conditions to dominate the period.
Some mid and upper level cloudiness will linger overnight and a
low level jet around 25 knots fog is not expected. Winds will be
southerly at 7 knots or less early tonight, becoming light and
variable through early Monday morning.
Monday, an upper level ridge overhead and warmer 500 mb heights
suggests afternoon convection will be weak and isolated. Hi-res
models are favoring the most activity in the csra, being further
away from the center of the upper ridge. Expect south winds from 5
to 10 kts.
Extended aviation outlook...low confidence in restrictions
in afternoon and evening convection each day. Low potential for
brief periods of early morning fog...mainly at ags/ogb.