Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Columbia SC
737 PM EDT Wednesday Jul 1 2015
upper and surface troughs will remain in the region through the
weekend. This will keep chances of showers and thunderstorms in
the forecast into early next week.
Near term /until 6 am Thursday morning/...
convection crossing Georgia and the upstate of South Carolina is
expected to reach the csra and the western midlands around sunset.
Our air mass remains unstable with precipitable water increasing and a middle level
short wave trough approaching from the west. Have increased probability of precipitation for
early tonight...with the highest probability of precipitation to the west. Should see
some weakening of storms crossing Georgia as they move into the csra
given time of day and limited shear. The temperature guidance was
consistent with lows in the lower 70s.
Short term /6 am Thursday morning through Friday night/...
upper trough deepen into the central Gulf states renewing an
increase in moisture over the area. Precipitable water values increase to around 2
inches and a couple of short waves will move through initiating
convection. Expect some of these storms to be severe producing
wind damage along with some hail. High temperatures will be around 90 and
into the lower 90s. Overnight lows will be in the low to middle 70s.
Long term /Saturday through Wednesday/...
models remain in good agreement. Flat upper level ridge over the
southern states and Gulf of Mexico will begin to force the upper level
trough northward. However will continue to see a threat of
afternoon and evening convection each day. Temperatures will be near
normal with highs generally 90 to 95 degrees and overnight lows
will be in the low to middle 70s. GFS continues to develop a weak
surface low over the Carolinas on the remains of the frontal
trough early next week. Will be interesting to see if the 12z
European model (ecmwf) comes in line.
Aviation /00z Thursday through Monday/...
a cluster of showers and thunderstorms moving through central Georgia
and upstate SC...driven by shortwave energy moving across the Tennessee
Valley...will move towards the terminals this evening. There is
some uncertainty as to what impact they may have due to loss of
daytime heating and waning instability but have decided to include
a mention of storms at ags/dnl/ogb from 02z-05z. Will include vcsh
at cae/cub and amend as necessary for thunderstorms and rain if needed.
All convection should wane by 06z-07z with a blanket of
convective debris cloud remaining over the area overnight along
with the thick smoke that has been hovering over the region today.
A weak low level jet and cloud cover should prevent much fog
development but confidence is low at ags/ogb depending on how much
rain occurs this evening and amendments may be needed later. Winds
pick up on Thursday after 16z from the west-southwest around 10-15
knots with gusts over 20 knots. There is a chance for isolated
storms Thursday afternoon but chances are low so will not include
at this time.
Extended aviation outlook...there is a chance of restrictions
through the period in mainly afternoon and evening thunderstorms...
and periods of morning fog.