area forecast discussion
National Weather Service Columbia SC
630 am EDT Wednesday Jun 19 2013
Synopsis...
the threat of showers and thunderstorms will remain across the
midlands and csra today as a cold front slowly sinks southward
across the area. Moisture will diminish from the north tonight
into Thursday as high pressure builds in from the north. The
chance for showers and thunderstorms will return for the weekend
as increasingly warm and humid conditions return.
&&
Near term /through tonight/...
through 9 am...surface cold front extending from Bishopville
through Newberry to Lincolnton at 10z. Scattered showers along and
south of the boundary. Instability weak and forcing limited with
precipitable water ranging from 1.50 to 2.00 inches.
After 9 am...the surface cold front should slowly move southward
across the area today. The latest RUC and NAM models indicate a
weak short wave crossing the area today. Have increased probability of precipitation
across the southeast to likely...kept chance probability of precipitation for today for
the the remainder of the area. Threat for convection will
gradually diminish from the north to south through this evening as
drier and more stable air filters in.
Went near consensus with highs in the middle 80s and lows in the middle
to upper 60s.
&&
Short term /Thursday through Friday night/...
mainly dry weather expected Thursday into Friday night as high
pressure ridges in from the north. Highest precipitable water
will be south of the csra. Consensus MOS temperatures look reasonable with
highs in the 85 to 90 degree range and lows in the 60s.
&&
Long term /Saturday through Tuesday/...
medium range models in fairly good agreement with a weak upper
level low affecting the southeastern states. The flow around surface
high pressure located off the Atlantic coast will bring increasing
moisture to the region. As a result we can expect a chance of mainly
diurnal convective activity...along with seasonably warm temperatures.
&&
Aviation /10z Wednesday through Monday/...
a mixture of VFR and IFR conditions at the taf sites this morning.
Mainly due to low ceilings and some light fog. 88d continues to show
..mainly showers moving northeast across the area this morning. The
activity is along/south of a cold front that is trying to move
slowly southeast over the area. Expect conditions to return to VFR
at all taf sites between 12z-14z. As long as frontal boundary is
across the County Warning Area...there will be a chance of showers/thunderstorms
through the day. Have not included any mention of precipitation at
this time as lack of confidence of placement/timing of scattered
showers.
By tonight...model time sections show some low level moisture with
the 06z NAM more moist than the 00z GFS. Expect VFR conditions
through 06z...but some MVFR conditions may be possible beyond the
taf period.
Extended aviation outlook...possible MVFR conditions Thursday
morning. A slight chance of mainly afternoon/evening thunderstorms
through the period.
&&
Cae watches/warnings/advisories...
SC...none.
Georgia...none.
&&
$$
