Scientific Forecaster Discussion
fxus62 kcae 230845
Area forecast discussion
National Weather Service Columbia SC
345 am EST Tue Jan 23 2018
a cold front will move through the forecast area this morning.
Breezy conditions will be associated with the front through
this afternoon. Showers will move east of the area this
morning. Dry ridging will follow the front and dominate through
Near term /through tonight/...the cold front and associated
showers will push east of the forecast area this morning. Strong
shear is associated with the front. The kcae 88d VAD wind
profile indicated 3000-foot wind around 45 knots early this
morning. Surface-based Li values were around 0. Despite the
strong shear the chance of severe wind in the shallow convection
is diminished. Observation trends support gusts near 25 knots
in some of the showers. Drying will occur behind the front late
this morning and afternoon. The NAM and GFS forecast soundings
and expected mixing plus the GFS lamp support wind gusts near
25 knots. We have posted a lake Wind Advisory through the
afternoon. Diminished mixing and a weakening pressure gradient
will result in less wind beginning this evening. We followed the
higher temperature guidance today because of a relatively warm
start along the cold front. Used the guidance consensus for the
Short term /Wednesday through Thursday night/...
the models have been consistent with dry surface ridging
dominating. There may be some cloudiness associated with a mid-
level shortwave trough Wednesday into Wednesday night but expect
this cloudiness will be limited because of the dry air mass.
The GFS and NAM MOS support west wind around 10 mph Wednesday
with the surface ridge moving into the area. Wind should be
light with the ridge over the area Wednesday night through
Thursday night. The temperature guidance was close with lows
around freezing and highs near 60.
Long term /Friday through Monday/...
the GFS and European model (ecmwf) show dry ridging dominating through Friday.
The models exhibit a moisture increase Saturday ahead of a cold
front and in an onshore flow directed into the area by high
pressure centered off the mid-Atlantic coast. Moisture may be
deepest Saturday night and Sunday with the frontal system in the
area. The European model (ecmwf) timing is closer and indicates rain continuing
through Sunday. The GFS and European model (ecmwf) ensemble means support the
highest pops Saturday night and Sunday. The GFS and European model (ecmwf) MOS
support above normal temperatures during the medium-range period.
Aviation /08z Tuesday through Saturday/...
restrictions possible this morning with VFR conditions by late
Cold front will push into the area later this morning. Strong low
level moist southerly flow ahead of the front will continue to
provide strong moisture advection into the region and low clouds and
scattered precipitation will continue until around 12z. MVFR/IFR
restrictions possible through 15z. Chances of rain decrease behind
the front as drier air works into the region from the west. VFR
condition should return by early afternoon.
Winds will pick up with the front moving into the area with breezy
conditions through the end of the 24-hr taf period. Wind shear will
also be possible early this morning given the strong low level jet
so have included low level wind shear from around 08z-12z. Strong winds 10 to 15
knots with gusts to 20-25 knots expected by late
Extended aviation outlook...no significant aviation concerns.
Georgia...Lake Wind Advisory until 6 PM EST this evening for gaz040-
SC...lake Wind Advisory until 6 PM EST this evening for scz015-016-