Area Forecast Discussion
Issued by NWS Columbia, SC
FXUS62 KCAE 100849
Area Forecast Discussion
National Weather Service Columbia SC
349 AM EST Sat Dec 10 2016
Cold high pressure will remain over the area through tonight. The
ridge will shift off the coast Sunday and temperatures will begin
to moderate. Rain chances will increase early next week as a cold
front moves into the region.
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Broad upper trough over the eastern CONUS this morning. Upper
level flow will become more zonal later today. Surface ridge from
the Mid Atlantic to eastern Georgia. Air mass remains dry and
unseasonably cold. After cold start this morning temperatures
should rise to 45 to 50 degrees this afternoon...similar to
yesterday under full insolation with weak downslope flow.
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
Surface ridge will move slowly off the Mid Atlantic coast tonight
and Sunday with coastal trough developing along the Carolinas.
Potential for radiational cooling tonight with clear skies and
light surface winds...although models suggest boundary layer winds
increasing by Sunday morning. Stayed close to Mos temperature
guidance in the mid 20s...10 degrees below normal.
Clouds and moisture will gradually increase on Sunday as surface
winds shift from northeast and weak isentropic lift develops.
Possible weak cold air damming although moisture appears shallow.
Tricky temperature forecast Sunday with considerable clouds in the
afternoon so stayed on cool side of Mos consensus. Pop guidance
continues to suggest high uncertainty...but given increase in
moisture/isentropic lift went with slight chance to chance pops
late Sunday night. Precipitation should be light with focus in the
Mountains near a cold front. Moderating temperatures Monday as low
level flow shifts to southwest ahead of approaching cold front.
Low pressure over the Great Lakes moves to New England later
Monday will drive cold front into the area. Moisture possibly
deepening especially Monday evening as front approaches.
Precipitable water highest...near 1.25 inches in the southeast
SC/GA. Continued chance pops increasing a bit Monday night as lift
strengthens associated with frontal boundary in the area/possibly
becoming stationary. But POP guidance continues to indicate
uncertainty/large standard deviation. ECMWF has higher pops Monday
night associated with weak low pressure along front in the Gulf
coast area lifting northeast.
.LONG TERM /TUESDAY THROUGH FRIDAY/...
The frontal boundary near the area or moving north Tuesday as a
warm front. Another cold front is forecast to cross the area
during the late Wednesday early Thursday time frame. Models show
moisture lingering in the area through late Wednesday night with
unsettled conditions expected. Continued with chance pops through
Wednesday given uncertainty due to model spread. Dry surface high
pressure will return to the area later in the week...although
moisture may spread east from the Midwest. Above normal high
temperatures are forecast through mid- week with the frontal
boundary in the area. Below normal highs are forecast for Thursday
and Friday given the modified Arctic air mass building into the
area in the wake of the front.
.AVIATION /08Z SATURDAY THROUGH WEDNESDAY/...
VFR conditions throughout the TAF period.
High pressure will remain in control of the region through the taf
period along with cool and dry air. Winds will be variable at 5
knots or less through the period with clear skies. With the dry
air across the region fog is not expected.
EXTENDED AVIATION OUTLOOK...Restrictions possible Sunday night
through Wednesday as a frontal system crosses the region.