Area Forecast Discussion
Issued by NWS Charleston, SC
FXUS62 KCHS 311145
Area Forecast Discussion
National Weather Service Charleston SC
745 AM EDT TUE MAY 31 2016
Remnant low pressure of Bonnie will continue to meander off the
upper South Carolina coast today, before gradually lifting
northeast Wednesday into Thursday. A weak cold front could then
approach the region late in the week and become stationary this
.NEAR TERM /THROUGH TONIGHT/...
Today the remnant surface low south of the Grand Strand is
expected to ease further offshore and just a tad to the ne away
from the forecast area; a similar motion is also anticipated with
the mid level vort max. Deepest moisture will only slowly strip
out and linger across the Central South Carolina coastal zones
where we forecast 30-50 pops today, highest over ne Charleston
County and Berkeley County. On the fringe of the deeper moisture,
diurnal instability will be modest and strong insolation will
result in decent thermodynamics along the Savannah River and the
I-95 corridor. Pockets of diurnal convection along mesoscale
boundaries should result in isolated showers and tstms this
afternoon across the remainder of the forecast area. Forecast
downdraft capes are generally weak but cannot rule out a couple of
storms producing some gusty winds and spotty downpours. Hot
weather across se Georgia where highs should reach the lower 90s
in some areas.
Tonight...There is still a potential for isolated showers along the
central South Carolina coast but chances are becoming slimmer as
the low eases away. Otherwise is should be partly cloudy with lows
in the upper 60s to around 70.
.SHORT TERM /WEDNESDAY THROUGH FRIDAY/...
Remnants of Bonnie will meander near the North Carolina coast
Wednesday into Thursday, leaving a rather ill-defined pressure
pattern over the local area. The remnant low will finally lift
northeast on Friday while a weak, slow-moving front approaches the
region from the west. More typical summertime rain chances expected
through the period, with coverage peaking in the afternoon and
evening when instability is greatest. Severe parameters aren`t too
impressive with lack of shear and no significant forcing mechanisms,
but sufficient CAPE and moisture could support a couple stronger
storms with gusty winds the main hazard. Rising heights aloft will
support temperatures near or slightly above normal. Highs in the
upper 80s/low 90s away from the coast; lows around 70.
.LONG TERM /FRIDAY NIGHT THROUGH MONDAY/...
Models in pretty good agreement through the long term period. Weak
front stalled over the region will likely dissipate over the weekend,
before another cold front approaches and crosses the area early
next week. Typical diurnal convection expected, with perhaps
greater coverage Sunday and Monday with the front in the vicinity.
Tuesday looks to be the driest day of the period as the bulk of
precipitation associated with the front shifts offshore and high
pressure begins to build in from the northwest. Temperatures
mainly near normal.
.AVIATION /11Z TUESDAY THROUGH SATURDAY/...
KCHS: IFR/MVFR cigs into mid morning as enough of an inversion in
the boundary layer will likely exist to keep moisture trapped
across the immediate area. Radar trends suggest dry weather is
likely but showers and isolated tstms may redevelop late morning
and especially this afternoon. Outside of convective rains
pockets...conditions should become VFR this afternoon and evening.
Late tonight...cannot rule out some low clouds moving back in but
we maintained VFR for now.
KSAV: VFR. Isolated SHRA/TSRA possible this afternoon. Patchy
low clouds and fog also a small possibility late tonight.
EXTENDED AVIATION OUTLOOK...Mainly VFR. Low risk for flight
restrictions from mainly afternoon showers/thunderstorms and
early morning fog/stratus.
Winds have become more sw and w overnight but are forecast to veer
w and nw by dawn before becoming variable with near shore sea
breeze influences this afternoon. Directions could remain rather
variable at times tonight. Speeds through sunrise on Wednesday
will be below 15 kt with seas 2 to 3 ft...highest well off the
Charleston County where a few 4 footers cannot be ruled out this
Wednesday through Sunday: Weak pressure pattern will be in place for
the second half of the work week as remnant low pressure of Bonnie
lingers to the north. Winds on average will be 10 knots or less
through Friday with seas 1 to 3 feet. Pressure gradient will begin
to tighten over the weekend as the coastal waters become sandwiched
between high pressure to the east and an approaching front to the
west. South/southwest winds will increase as a result, but
conditions are still expected to stay well below small craft