Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Columbia SC
641 am EST Thursday Feb 11 2016
a dry air mass will remain in place over the forecast area today.
Moisture will increase tonight ahead of weak low pressure. The
low will be near the South Carolina coast early Friday and farther
off the coast Friday afternoon. Much of the moisture associated
with the low will be east of the forecast area.
Near term /through tonight/...
a surface pressure ridge will be north of the forecast area with
a dry frontal zone just to the south today. The pressure gradient
has relaxed and much less wind will occur today compared to
yesterday. The models have been consistent indicating low pressure
developing along the front and tracking eastward with a moisture
increase in the forecast area tonight. An increase in cloudiness
should occur but moisture will likely remain too shallow for
precipitation as indicated by model time-height displays.
Also...there will be 850 mb westerly flow and just weak isentropic
lift. The NAM...GFS...and European model (ecmwf) MOS keep probability of precipitation less than 20
percent through tonight. The temperature guidance was close.
Short term /Friday through Friday night/...
the models display low pressure near the South Carolina coast
early Friday with the system shifting farther northeast during the
afternoon. Much of the moisture will remain northeast and east of
the forecast area. The models show little isentropic lift with
westerly 850 mb flow. We leaned toward the lower guidance probability of precipitation with a
forecast of a slight chance of precipitation in the northeast
section. The top-down method using the NAM and GFS supported a
mix of snow...sleet and rain. The NAM...GFS...and European model (ecmwf) all
indicated quantitative precipitation forecast of 0.01 of an inch or less. Further drying will
occur Friday night with low pressure well to the northeast and
high pressure building into the area from the west. The
temperature guidance was consistent.
Long term /Saturday through Wednesday/...
the GFS and European model (ecmwf) display dry high pressure near the forecast area
Saturday and Sunday. The models show the ridge shifting off the
coast for Monday and Tuesday with a frontal system moving into the
forecast area. Cold air may linger with a wedge pattern Monday
into Monday night. The GFS partial thicknesses indicate possible
freezing rain in the northwest section. It will likely be dry
behind this system for Wednesday. The GFS...ECMWF...and ekd MOS
have probability of precipitation less than 10 percent Saturday and Sunday...30 to 70
percent Monday and Tuesday...and less than 20 percent Wednesday.
Aviation /12z Thursday through Monday/...
VFR forecast throughout the taf period.
Light westerly winds early this morning increasing to around 7-10
kts by early this afternoon. Will see high and middle level clouds
increasing later today.
Extended aviation outlook...MVFR ceilings possible Thursday night
into Friday as a low pressure system affects the region. Ceiling/visibility
restrictions possible Monday as a southern stream low pressure
system crosses the region.