Area Forecast Discussion
Issued by NWS Columbia, SC
FXUS62 KCAE 291021
Area Forecast Discussion
National Weather Service Columbia SC
621 AM EDT WED JUN 29 2016
A surface trough of low pressure will move into the Upstate today
then stall. The chance for showers and thunderstorms will continue
across the region through the weekend. High pressure over the
western Atlantic will ridge into the southeastern states this
weekend into early next week.
.NEAR TERM /THROUGH TONIGHT/...
A broad upper level trough will remain over the eastern conus with
an upper level ridge over the west. A weak surface boundary will
move into the Upstate and stall as high pressure builds into the
Ohio Valley. Deep moisture will linger along the coast.
Precipitable water is forecast to range from near 2.0 inches over
the lowcountry to around 1.5 inches across the central Midlands to
around 1.00 inch over the Upstate. Forcing for convection appears
weak. Showers and thunderstorms should focus in the coastal plain
and in the upstate near trough. Expect Isolated convection across
the Midlands today...with dry air aloft and moderately stronger
deep layer shear. Pops generally 30 percent or less. Expect a
diurnal trend with convection diminishing during the evening.
Have indicated afternoon high closer to the warmer MOS
guidance...in the low to mid 90s. Went with persistence for
overnight lows in the upper 60s to mid 70s.
.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
Little change in the weather pattern through Thursday night.
Broad upper troughing will continue over the eastern states. A
surface trough will linger over the Upstate. The airmass is
forecast to become moderately unstable with lifted indices minus
4C to minus 7C and precipitable water 1.5 to 2.0 inches. Have
indicated scattered showers and thunderstorms with pops ranging
from around 30 percent west to 40 percent east. The temperature
forecast was consistent with highs in the upper 80s to mid 90s
and lows in the lower 70s.
.LONG TERM /FRIDAY THROUGH TUESDAY/...
Models remain in good overall agreement through the period
showing quasi-zonal flow aloft and the subtropical ridge off the
coast. A stationary boundary is expected to be near the western
portion of the forecast area Friday and Saturday and will serve as
a focus for convection. A cold front will approach the area from
the north/northwest over the weekend but is expected to become
stationary over the area early next week. Temperatures through the
period are forecast near to a few degrees above normal.
.AVIATION /10Z WEDNESDAY THROUGH SUNDAY/...
Mainly VFR conditions expected today although early morning fog
MVFR fog possible...mainly at AGS/OGB.
Mainly mid and high level ceilings. Afternoon convection should
be focused in the coastal plain today and in the Upstate region.
So although isolated thunderstorms possible...low threat to impact
terminals...so scattered cumulus through the day with mid level
ceilings. Winds light and variable mainly southeast in the
afternoon. Some potential for patchy fog late tonight...mainly
AGS/OGB but confidence low.
EXTENDED AVIATION OUTLOOK...Restrictions possible in diurnal
convection each afternoon through the period along with late night