Area Forecast Discussion
Issued by NWS Columbia, SC
FXUS62 KCAE 290522
Area Forecast Discussion
National Weather Service Columbia SC
122 AM EDT FRI JUL 29 2016
High pressure over the region will keep above normal temperatures
in the forecast through the end of the week. Afternoon thunderstorms
will be isolated the next couple of days...possible better chance
over the weekend into next week as moisture increases.
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
Upper level ridge continues over the Southeastern states and
offshore. Best dynamic tonight remain off to the west of the cwa.
Regional radars showing some light sprinkles pushing across the
northern CSRA, and there is a small possibility this could
briefly brush the extreme western Midlands. However, majority of
the night for the area will be dry and warm. A strong low-level
jet tonight should help keep winds up, and low-levels mixed.
Overnight lows falling into the middle to upper 70s.
.SHORT TERM /6 AM THIS MORNING THROUGH SUNDAY/...
The ridge will weaken Friday as an upper trough moves eastward. A
surface trough in the area may trigger some convection as a few
shortwaves support development. Instability remains weak on
Friday...so afternoon showers/thunderstorms should remain
isolated or widely scattered at best. The good news is the chances
for afternoon/evening showers and thunderstorms will be increasing
over the weekend. Thanks to slightly colder air aloft...increased
low-level moisture and weak trough/frontal boundary in the
vicinity should be a much better focus for convection than the
area has seen in awhile. Chance pops mainly afternoon showers and
thunderstorms over the weekend. Weak cold advection noted Friday
although may be offset by downslope flow. Slight decrease in
maximum temperatures over the weekend although still above normal
for late July. Also overnight minimum temperatures continue to be
above normal through the period.
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
Both ECMWF and GFS indicate the mid/upper level ridge will
continue to weaken from Sunday night through much of next week. As
main ridge will continue across the wrn/cntrl U.S. and trough
lingers along the ern portion of the country. This will support
a general increase in pops as shortwaves move over the region and
lee-side troughing promotes convergence. Scattered thunderstorms
expected each day as surface high pressure shifts eastward and a
backdoor front moves into the mid- Atlantic States. The best
chance for widespread convection appear to be Sunday
afternoon/evening through Monday/Monday night. The synoptic
pattern supports above normal temperatures with highs in the
low/mid 90s and overnight lows in the low/mid 70s.
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
Outside of isolated thunderstorms Friday, high confidence in VFR
conditions through the 24 hour TAF period.
Models indicate a 30 to 35 kt LLJ tonight which will promote low
level mixing. Surface winds should stay SW around 5 kts throughout
the night. Low level mixing and dry air will prevent fog/stratus
Upper level ridging over the region will weaken as a few
shortwaves move through the trough in the central US. Increased
atmospheric moisture and convergence along a surface trough will
allow for isolated convection Friday afternoon. Limited
instability and relatively warm mid-levels suggests any
thunderstorms would be weak and isolated. Low threat for
thunderstorms to impact terminals. Scattered high level cumulus
in the afternoon. Expect W/WSW winds to gust up to 20 kts. LAMP
guidance suggests higher gusts will be possible but capped the
TAFS at 20 kts given the pressure gradient may be weaker than the
EXTENDED AVIATION OUTLOOK...Low potential for restrictions in
afternoon and evening convection each day.