Scientific Forecaster Discussion
area forecast discussion
National Weather Service Columbia SC
1236 am EST Friday Dec 26 2014
dry high pressure will dominate through Friday. The chance for
rain will return late Saturday and into Monday as low pressure
develops along the Gulf Coast states and moves northeast.
Near term /until 6 am Friday morning/...
the high will be centered near the forecast area tonight. Expect
clear skies and light winds with strong net radiational cooling.
The temperature guidance was consistent with lows mainly in the
Short term /6 am Friday morning through Friday night/...
upper ridge will build over the eastern half of the country
Friday as a southern stream trough digs across the southwestern
US. Surface high pressure centered over the southeastern states
will promote dry weather and mostly sunny skies across the region.
Above normal highs under nearly full sunshine in the upper 50s to
lower 60s expected on Friday. Mav guidance was a few degrees
warmer than the met. Raised temperatures a couple of degrees and came out
in between the mav and met guidance. Increasing high clouds ahead
of the next approaching system late Friday will promote overnight
lows in the middle 30s to near 40.
Long term /Saturday through Thursday/...
upper ridge will shift off the East Coast on Saturday with broad
troughing over the central US promoting southwesterly flow aloft.
Surface high pressure will shift east off the Carolina coast on
Saturday as the next frontal system approaches. Models show an
area of low pressure deepening and moving northeast across the
Great Lakes region toward southern Canada Saturday into Sunday
morning. A wave of low pressure also develops along the western
Gulf and moves northeastward over the Carolinas on Sunday.
Moisture and clouds will increase ahead of the approaching system
Saturday and into Sunday with increasing chances of rain. Models
show precipitable water increasing through the day Saturday
reaching one inch by the afternoon and continuing to rise into
Sunday morning to over 1.6 inches. Surface low pressure will shift
east across the Carolinas late Sunday while slowly bringing a
cold front across the area into Monday. Low pressure will
shift northeastward on Monday with the best moisture shifting
east late. Upper level flow becomes more zonal Wednesday and Thursday
with surface high pressure building in from the central Continental U.S. On
Wednesday. Above normal temperatures expected Saturday through Monday
with temperatures returning to near normal by the end of the long
Aviation /06z Friday through Wednesday/...
in general...VFR conditions will continue across the taf sites
through the period. However...with mostly clear skies and calm winds
some patchy light fog as formed. Will mention some MVFR conditions
at ogb...cub and ags through 12z. At the surface...high pressure
centered over Georgia/Carolinas will continue to produce mostly
clear skies and calm/light winds through the period.
Extended aviation outlook...restrictions possible Saturday evening
through Monday as the next frontal system moves into the area and
moderate to heavy rainfall over the past few days has yielded
widespread rainfall amounts of 2 to 4 inches. Main-Stem rivers
have responded to the rain. Although upstream amounts were a
little lower than across the midlands...significant rises are
expected during the next 24 hours...a few rivers may approach