Area Forecast Discussion
Issued by NWS Greer, SC

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FXUS62 KGSP 310704

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
304 AM EDT TUE MAY 31 2016

The remnants of tropical system Bonnie will slowly lift northeast
along the Carolina Coast over the next couple of days. Moisture will
increase ahead of a weak cold front approaching from the northwest
on Friday. The front will stall in the vicinity over the weekend,
but a stronger cold front will push through the region on Sunday


As of 300 AM EDT...The remnant circulation of Bonnie will remain
near the Myrtle Beach area today, as it continues its eastward
drift. This will keep a NELY low-mid level flow over the CWFA today.
Guidance in good agreement on a little bit higher CAPE this AFTN
than yesterday. The high res models in particular show the NC mtns
being a focus for convection by early AFTN. The activity will then
try to survive as it drifts toward the south into the piedmont thru
the evening. So I expect a similar situation today as yesterday,
with perhaps a little greater coverage. One storm became marginally
severe yesterday. So I would not be surprised if a couple of the
strongest storms produced large hail and/or downed a couple trees
today. Temps will be above normal, in the 70s to lower 80s in the
mtns and mid to upper 80s in the piedmont.

Tonight...convection should gradually wane leaving a fair amount of
debris cloudiness around thru much of the night within weak flow
aloft. Temps will continue to be a couple categories above normal,
with lows mainly in the 60s.


As of 245 AM EDT Tuesday: Upper level heights will briefly build
over the region on Wednesday as the remnant circulation of Bonnie
moves northeast along the NC coast and a prominent northern tier
trough moves slowly east from the Dakotas to the Great Lakes.
Convection will initiate once again over the mountains Wednesday
afternoon, move off into the adjacent foothills through evening, and
then largely dissipate overnight. Expect more instability late Wed
than will be observed on Tuesday, with an uptick in severe
thunderstorm potential.

Ridging will persist over the southeast Thursday into Friday as a
southern stream closed low develops and lingers over TX. Diurnal
convective coverage will likely increase a bit further, with
initiation again over the mountains by mid afternoon but with
perhaps more coverage advecting east into the piedmont. Instability
should be the highest of the week on Thursday afernoon/evening, with
plenty of 2500 to 3000 J/kg SBCAPE values across the region and
scattered severe storms quite possible. A weak cold front will
slowly approach from the northwest during this period and then
finally settle southeast through the region Friday night, or
gradually dissipate. Maximum temperatures through the period will be
slightly above climo, with mins a good 5 to 10 degrees above climo.


As of 245 AM EDT Tuesday: The southeast ridge will slowly break down
over the weekend as the digging Great Lakes system starts to carve
out an eastern trough. Although a weak fropa may start off the
period, boundary layer moisture will not dry out appreciably and
additional diurnal convection is likely by Saturday afternoon and

Better forcing, moisture, and shear will come together on Sunday as
heights continue to fall aloft. Upper jet divergence should arrive
along the southern Appalachians, and southwesterly 850 mb flow will
increase to permit slightly better storm organization ahead of the
next approaching cold front. This stronger front is expected to
cross the region Sunday night into Monday - with drying developing
everywhere but the TN border area in weak but moist upslope flow.
Temperatures will fall to near or just below climo on Monday.


At KCLT...skies have cleared out for the most part. So now the
concern will be if any fog and/or stratus is able to develop within
a moist air mass during the pre-dawn hours. guidance is mixed on how
much (if any) restrictions will develop early this morning. A dewpt
depression of 5 deg F at time of TAF issuance has me leaning toward
perhaps a little stratus. I expect a little greater coverage of
convection today, and will highlight with a PROB30 for late aftn
into early evening. Winds will continue to favor a NE direction and
remain light.

Elsewhere...Measurable rain occurred early this evening at all sites
except KGMU. GSP got the most rain and looks most primed for at
least ground fog to develop before daybreak once the debris
cloudiness dissipates. Will continue a tempo for mvfr vsby there.
The sites may see some mvfr fog as well (except not likely at GMU).
This aftn, another round of showers and tstms is expected to develop
acrs the mtns and track generally south in the Upstate and NC
foothills again. All sites will feature PROB30 for tsra. Winds will
continue to favor a N to NE direction today and remain light.

Outlook...Bonnie`s remnant low is expected to move very slowly up
the coastal Carolinas over the next several days, maintaining
increased precip and morning stratus chances at KCLT. Otherwise,
patchy fog chances continue at KAVL each morning, with scattered
afternoon/evening SHRA/TSRA increasing in coverage throughout during
the week.

Confidence Table...

            07-13Z        13-19Z        19-01Z        01-06Z
KCLT       High  83%     High 100%     High 100%     High 100%
KGSP       High  90%     High 100%     High 100%     High 100%
KAVL       High  90%     High 100%     High 100%     High  96%
KHKY       High  90%     High 100%     High 100%     High 100%
KGMU       High 100%     High 100%     High 100%     High 100%
KAND       High  96%     High 100%     High 100%     High 100%

The percentage reflects the number of guidance members agreeing
with the schedule TAF issuance flight rule category. Complete hourly
experimental aviation forecast consistency tables and ensemble forecasts
are available at the following link:




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