Area Forecast Discussion
Issued by NWS Columbia, SC
FXUS62 KCAE 242036
Area Forecast Discussion
National Weather Service Columbia SC
436 PM EDT Mon Apr 24 2017
A low pressure system will slowly cross the region through
tonight, resulting in periods of showers. The low pressure
system will finally exit the region Tuesday. Dry weather and
above normal temperatures will return by the middle of the week
as high pressure takes control. A cold front could affect the
area early next week.
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
This afternoon: Surface low pressure situated across
southeastern SC will slowly push towards the coast. This is in
response to the main upper low that is moving into eastern GA.
Ahead of the upper low, showers and thunderstorms will remain
possible through the afternoon and into the early evening
hours. PW values remain between 1.2 and 1.5 inches across a
large portion of the area, which could lead to some heavy
rainfall in any of the slower moving or training storms. Much of
the heavy rainfall has moved out of the CSRA, and have dropped
the Flash Flood Watch for that region. The Watch remains in
effect for the Central and Northern Midlands.
Confidence remains low for severe convection given the current
position of the surface low and frontal boundary generally south
of the forecast area. Cannot rule out gusty winds and possibly
some small hail with the stronger storms this afternoon, mainly
across the far eastern Midlands.
Temperatures this afternoon will remain quite cool across the
northern and western Midlands, with those areas remaining in the
cooler stable air wedge. Areas farther south and east should
see warmer temperatures closer to the front and surface low.
Trended cooler with highs in the lower 60s northern and western
Midlands with mid 70s in the far southeastern Midlands.
Tonight: The upper low will move northeast along the SC coast
overnight. The associated surface low will drift east and
eventually merge with a low off the southeast coast. Will see
lingering showers associated with the upper low, but the bulk
of precipitation will be northeast of the forecast area. Cloudy
skies will persist with lows in the mid to upper 50s.
.SHORT TERM /6 AM TUESDAY MORNING THROUGH TUESDAY NIGHT/...
The upper low and surface low pressure will lift northeastward
away from the region Tuesday with an upper ridge to the west
shifting eastward over the area. There could be some scattered
showers across the Midlands through midday Tuesday but any
precipitation should be shifting north of the forecast area
during the afternoon. Clouds will be slow to clear. Temperatures
will be warmer but still expect to see a gradient in highs
ranging from near 70s in the northern Midlands to near 80 in the
CSRA. Skies should finally clear out Tuesday night with strong
net radiational cooling which will allow temperatures to fall
into the mid to upper 50s.
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
Above normal temperatures will return from midweek into the
An upper ridge will move over the forecast area Wednesday/Thursday
providing dry weather and moderating temperatures. A
deamplifying upper trough will approach late Thursday into
Thursday night breaking down the upper ridge and bringing a
slight chance of showers to the western part of the forecast
area. Deep troughing over the western section of the country
Friday/Saturday will result in the upper ridge rebuilding over
the southeastern states. At the surface high pressure over the
western Atlantic will provide southerly low-level flow and
increasing moisture into the region resulting in warm and more
humid conditions. An upper trough crossing the Great Lakes
Region will drive a cold front our way early next week...
bringing a chance of showers and thunderstorms Monday.
Temperatures will be 10 to 15 degrees above normal through the
period with highs in the upper 80s to lower 90s and lows in the
.AVIATION /21Z MONDAY THROUGH SATURDAY/...
Mainly ifr/mvfr conditions expected through the period.
The upper low will slowly traverse the region through the
night. Widespread IFR/MVFR ceilings are expected to continue at
all sites, although some breaks in the clouds may occur at
times. Much of the shower and thunderstorm activity, is expected
to shift just east of the TAF sites tonight, though continued
ifr ceilings once again expected through the night. Ceilings
should finally rise into the MVFR category around 15z,
with vfr possible near the end of the current taf period.
EXTENDED AVIATION OUTLOOK...No significant impacts expected.
SC...Flash Flood Watch until 8 PM EDT this evening for SCZ015-016-