Area Forecast Discussion
Issued by NWS Columbia, SC
FXUS62 KCAE 270223
Area Forecast Discussion
National Weather Service Columbia SC
1023 PM EDT Wed Oct 26 2016
Fair and warm conditions will be the rule through early next week.
A weak front, with limited moisture, will traverse the forecast
area late Thursday/early Friday, with fair and warming conditions
expected Friday afternoon into the weekend. A weak dry front
moving through late Sunday/early Monday will reinforce continued
dry and warm conditions early next week.
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
High pressure will ridge into the forecast area from the northeast
through tonight. Satellite trends support high cloudiness over the
forecast area ahead of the upper trough. As the ridge shifts
eastward low-level flow will become southeasterly into the
forecast area overnight. The moisture combined with nocturnal
cooling may result in stratus or fog during the early morning
hours. However, based on crossover temperatures and upper-level
moisture limiting net radiational cooling plus low sref
probabilities expect fog will be limited. The HRRR also suggested
more widespread visibility restrictions will remain south of the
forecast area. We forecasted just patchy fog. Mos guidance
accepted so expect warmer readings than last night with
temperatures in the mid 40s to lower 50s.
.SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/...
Upper ridge over the Rockies, with upper troughiness over the E
CONUS. Surface high axis over the area weakens and pulls east
tonight into early Thursday ahead of an approaching weak surface
boundary. A weak surface boundary is expected to slowly move
through the forecast area late Thursday into Friday. Best upper
dynamics to remain to our north, with limited moisture for the
system to work with. Latest model guidance confirming limited
moisture. A blend of model guidance suggests slight chance POPS
at best, favored towards the N/NE forecast area mainly late
Thu/Thu night. High pressure will build in from the west later on
Friday into Friday night. Temperatures will be several degrees
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
Behind the weak front/trough, surface high pressure will shift
into the region late Friday into the weekend. Upper trough over
the E CONUS will lift to the north some Fri thru Sun, with upper
ridge center shifting east along the Gulf coast, providing a
continued dry WNW to NW flow aloft for our area. Models continue
to indicate a dry front moving through the area late Sunday/early
Monday. High pressure center to build into the eastern seaboard,
and also indicate a building upper ridge over the SE CONUS
Mon/Tue, appearing to ensure dry conditions, with above normal
temperatures, through the period.
.AVIATION /03Z THURSDAY THROUGH MONDAY/...
Sites may experience restrictions due to low stratus and fog early
Thursday morning, but confidence is low.
Surface high pressure ridging into the Carolinas has created a
tight moisture gradient across the forecast area. Crossover
temperatures ranging from the upper 30s in the northern Midlands
to near 50 degrees in the CSRA. Models indicate increased low
level moisture advection, particularly in southern SC and the
CSRA, may lead to fog or stratus early Thursday morning.
Radiational cooling conditions will not be ideal. Broken high
clouds will continue streaming into the area overnight, increasing
insulation. Minimum temperatures are also not forecast to near the
crossover temperatures, except in the CSRA. However increasing
moisture in SE flow, decoupled winds and increasing specific
humidity with height does favor fog development. Model guidance
has also supported patchy areas of fog or stratus. Fog will be
most likely at AGS but conditions may be sufficient for patchy fog
or low clouds across the forecast area.
Thursday morning, patchy areas of fog/stratus will dissipate by
late morning with light south winds. Winds will become
southwesterly around mid-day as the cold front approaches from
the north. Limited moisture will limit the chances for showers
late Thursday as the cold front moves into the area.
EXTENDED AVIATION OUTLOOK...Fog or stratus possible Friday morning
with some lingering low level moisture over the region.