Scientific Forecaster Discussion
fxus62 kcae 230022
Area forecast discussion
National Weather Service Columbia SC
822 PM EDT Thu Jun 22 2017
considerable moisture continues to stream into the area in the
southerly flow between high pressure off the southeast coast and
the remnants of Cindy to the west. A slow moving cold front
will affect the forecast area Saturday through Monday.
Near term /until 6 am Friday morning/...
abundant moisture remains across the region as remains of ts
Cindy continue moving inland over la/Arkansas with high pressure
offshore of the southeastern states. WSR-88D currently shows
showers and isolated thunderstorms across the eastern midlands
and along the coast with partly sunnies skies elsewhere.
Instability will remain moderate over the next several hours
then begin diminishing overnight. Limiting factor currently is
the lack of a trigger mechanism and with sunset shortly will be
depending on boundary intersections to initiate new convection.
Cloud cover will remain extensive, with low stratus expected to
develop during the early morning hours. There is even the
potential for some patchy fog to develop toward daybreak once
again, however it does appear that surface winds may not fully
decouple everywhere, somewhat limiting the overall potential.
Temperatures will remain rather mild due to the cloud cover,
with lows forecast to be in the lower to mid 70s.
Short term /6 am Friday morning through Sunday night/...
remnants of Cindy will be moving off to the north of the
forecast area ahead of an approaching cold front Friday into
Saturday. Cindy will race rapidly northeastward into Saturday
ahead of the front, with upper ridging across the western
Atlantic helping to keep the bulk of the moisture from Cindy
north of the cwa. A decrease in clouds will bring some sunshine
back to the area Friday, and expect to see some sea-breeze
convection moving inland by the afternoon hours. Friday should
start off mostly dry, then isolated to scattered showers/storms
by the afternoon with the sea-breeze. Friday night will see
additional showers off to the west of the area as the cold front
begins to approach from the west. Increasing rain chances on
Saturday and Saturday night with chance pops expected as the
front begins to move into the forecast area. The main front
should be moving into the eastern portions of the the cwa by
Sunday morning. The front will slow on Sunday, with a weak low
possibly moving along the boundary during the day. Will continue
with chance pops through Sunday night across the eastern cwa,
with slightly lower pops across the western counties further
away from the front.
As for temperatures through the period, it will remain rather
hot and humid ahead of the front. Afternoon highs in the lower
90s Friday and Saturday, with heat index values around 100 each
afternoon. Temperatures and heat indices slightly cooler on
Long term /Monday through Thursday/...
drier and cooler air should be pushing into the region by
Monday. May still see some lingering rainfall for a portion of
the day Monday, then the drier air will finally take control for
Tuesday through Thursday. Guidance continues to indicate
supports temperatures near to slightly below normal during the
Aviation /00z Friday through Tuesday/...
VFR conditions this evening expected to deteriorate to MVFR or
lower during the early morning hours.
Frontal boundary across central South Carolina in the vcnty of
cae/cub at 00z will lift north of the taf sites by 04z. Showers in
the vcnty of cae/cub will move north of the taf sites by 02z.
MVFR cigs expected to develop at all terminals overnight given the
abundant low level moisture. Several models indicated IFR cigs
09z-13z...so have continued a tempo group for IFR conditions.
Patchy fog could be an issue once again as well, but a 20 to 30
knot low level jet should prevent widespread dense fog development.
Should see conditions improving to VFR 15z-17z as southwest
winds increase to around 10 knots. Scattered convection possible
during peak afternoon heating, but probability too low to
include in tafs attm.
Extended aviation outlook...convection and associated restrictions
will be possible Saturday through Sunday ahead of a cold front.