Area Forecast Discussion
Issued by NWS Charleston, SC
FXUS62 KCHS 270224
Area Forecast Discussion
National Weather Service Charleston SC
1024 PM EDT Wed Oct 26 2016
High pressure will prevail through Thursday. A weakening cold
front should approach Friday followed by more high pressure for
the weekend and early next week.
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
Deep layered ridge will persist overnight with mainly dry
conditions. A weak shortwave approaching from the west will spread
increasing mid and high clouds across the area. Given the increase
in cloud cover, the temperature drop will slow down through the
overnight hours, with most areas bottoming out in the mid/upper
50s away from the coast. Patchy fog is possible across far
southeast GA but the clouds should limit coverage and density.
.SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY/...
Thursday and Thursday night: The pattern aloft will feature
nearly zonal flow to start the day ahead of a dampening trough
approaching from the west. The trough and energy associated with
it will dissipate upon approach and the feature will limp through
the forecast area overnight. At the surface, high pressure will
remain in control across the forecast area as a fast moving low
crosses the upper midwest and the Great Lakes. This system will
drag a cold front through the Tennessee Valley in the afternoon
but it is widely expected to remain north of the forecast area
through the overnight. An increase in upper level moisture is
expected during this time, but mid levels are still quite dry.
When combined with the lack of significant forcing, the forecast
remains dry through Thursday night. Instead, the biggest impact
will be a modest increase in clouds. There will be no appreciable
airmass change and highs will still rise to around 80 in the
afternoon. Overnight, look for lows mainly in the mid to upper
Friday through Saturday: Once the remnants of the Thursday trough
pass to the east a broad ridge will build across the southern CONUS.
Another area of high pressure will gradually build into the forecast
area through the first half of the weekend, and the forecast remains
dry and tranquil. Dry air, mostly clear skies, and well above normal
temperatures will prevail. Forecast highs are in the low to mid 80s
with lows in the mid to upper 50s.
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
Expansive deep layered ridging looks to persist through the period
with both the GFS and ECMWF indicating the center of the mid level
high will settle over the region during the first half of the
upcoming week. A backdoor dry cold front on Monday should turn the
low level flow more onshore, but this will do little to impact temps
which should continue to run well above climo. Many areas are likely
to see highs in the lower 80s with overnight lows in the mid 50s to
near 60 coast.
.AVIATION /02Z THURSDAY THROUGH MONDAY/...
VFR conditions are likely at KCHS and KSAV through 00Z Friday.
There is a low chance for MVFR cigs and perhaps light fog at the
terminals after 03Z-06Z tonight due to a weak coastal trough along
the Southeast coast.
Extended Aviation Outlook: VFR conditions expected to prevail
through this weekend with low probabilities for late night or
early morning restrictions in patchy fog prior to the weekend.
This Evening and Tonight: High pressure will dominate the coastal
waters with a east/northeast flow regime that gradually veers to
east and persists through tonight. Winds expected to remain at or
below 15 kt with seas 2-4 ft.
Thursday through Monday: High pressure will be the primary feature
across the local waters through the weekend and into early next
week. One weak front will approach the vicinity early Friday and
another will approach late Sunday night. Neither of these will have
noteworthy impacts on the local waters, other than to produce
variable winds for a period of time. Overall, winds will be less
than the 10-15 knot range with seas 2-4 feet. Some 5 foot seas will
be possible in the outer Georgia waters Thursday and Friday.