Special Weather Statement, NWS Greenville-Spartanburg, SC

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
301 PM EDT THU JUL 7 2016

.SYNOPSIS...
The warm and unstable airmass in place over the area will persist
into the weekend providing ample chances for widespread showers and
thunderstorms. A weak cold front will approach from the northwest
over the weekend and stall near the area through early next week.

&&

.NEAR TERM /THROUGH FRIDAY/...
A couple of areas of convection are evident across the CWA this
afternoon, one extending from the northwest NC Piedmont into the
northern Upstate, which aligns fairly well with short term model
depiction of DPVA associated with mesoscale convective vortex
spinning near the VA/NC border. Convection is limited to light
showers in the relatively stable air across NC, with an isolated
strong to severe storm ongoing within 2000+ J/kg air mass over the
Upstate, where more in the way of sun has been seen recently. The
second area of convection extends from the Knoxville area into
Madison County NC. This is more terrain induced, having developed
within a low level convergence zone downstream of the higher terrain
of the Cumberland Plateau. Some of the mesoscale guidance has picked
up on this activity, and tends to want to organize it and blow it
southeast across the forecast area through the afternoon. This seems
quite dubious, as the air mass over that way is not very unstable,
thus the probability that a strong cold pool will form and organize
convection is very unlikely. Will continue to allow pops to increase
to 50 percent across much of the mtns, and across the SE half of the
forecast area by late in the afternoon, as activity ahead of the MCV
moves into an increasingly unstable air mass.

Mid-level flow has become rather respectable downstream of the MCV,
with as much as 35 kts observed between 500-700 mb in the 12Z RAOB
from RNK. As a result, 0-3 km shear of 25-30 kts should promote
some degree of clustering along outflows, which would pose a risk of
damaging microbursts, mainly southeast of I-85.

Another MCS has recently crossed the Miss River into western
Kentucky and will continue to push steadily east, and likely develop
southward into a very unstable air mass across Middle Tenn. This
will likely initiate a well-developed cold pool over the next couple
of hours. However, it will encounter an increasingly stable air mass
as it moves across the Great TN Valley and surrounding areas
circa-early evening. Therefore, it's doubtful this activity will be
in any particularly intense state as it approaches the area this
evening, even if it does manage to hold together for that
long.

For tomorrow, the upper ridge is expected to begin building into the
area from the southwest. The main impact of this will be to increase
thickness values. Combined with a decent westerly downslope flow,
temperatures are expected to be very hot tomorrow, likely reaching
the century mark across much of the upper Savannah River Valley. The
warming mid-level temps will also tend to make the atmosphere less
supportive of deep convection, especially across the southern part
of the area, where pops will be advertised at less than slight
chance. Slight to low chances will be advertised across the north.
Dewpoints are expected to mix out somewhat in the westerly flow/
deep boundary layer regime. Thus, heat indices are generally
expected to top out at less than advisory criteria (105 outside the
mtns), but some portions of the upper Savannah River Valley and the
SC Lakelands will be close.

&&

.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/...
As of 200 PM EDT Thursday:  The short term fcst period kicks off on
Friday evening amidst deep layer ridging as an elongated H5
anticyclone remains draped across the southeast states, while a
close upper low and associated trof swing through the great lakes
region perhaps flattening the southern ridge a tad.  At the surface,
high pressure centered over the eastern Gulf will be providing ample
subsidence across much of the southeast, northward over the southern
Appalachians, while a weak cold front sweeps through the northern OH
valley.

Pattern evolution through the Saturday favors said cold front
sliding into the western NC high terrain by mid/late morning, before
stalling out.  Downsloping flow over the piedmont looks to be the
primary weather feature on Saturday as skies remain mostly sunny
ahead of the stalled front while llv subsidence keeps convection at
bay amongst temperatures in the upper 90s.  Profiles do exhibit
steep low/mid level lapse rates across the entire fcst area which
would support strong/severe convection, if the cap breaks.  However,
those same soundings favor much stronger subsidence across the
piedmont, and therefore warranting non mentionable pops, increasing
to chance levels over the mtns where upslope and frontal convergence
could initiate convection.

Meanwhile, a secondary/strong cold front looks to back door into the
region overnight into Sunday ahead of a sprawling area of high
pressure moving into/across the southern Great Lakes region.  At
this point operational guidance tends to diverge a bit regarding the
eventual evolution/outcome of this front.  The GFS centers the
surface anticyclone further south and thus is more aggressive with
the fropa pushing it south of the fcst area into the Midlands before
stalling out late in the day.  On the other hand, the ECMWF favors a
more northern centering of the sfc ridge and thus stalls the front
atop the fcst area.  Either way the front will most likely become a
focus for convection, the question is where does it set up.  Will
likely hedge with regards to the fcst thereby favoring chance pops
south of I40, tapering downward further north.  Temperatures on
Sunday will remain above normal, however nearly 5 degrees cooler
than that of Saturday.

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
As of 210 PM Thursday: the medium range fcst picks up at 00z on
Monday with lingering upper trofing over Northern New England and
steep upper ridging centered over the Central CONUS. The models also
generate an embedded upper shortwave on Sunday and move the feature
over the fcst area early Monday. Over the next couple of days, the
ridge axis will slide over the Eastern CONUS while a large cutoff H5
low follows in its wake but remains far to our NW. At the surface,
deep layer moisture is expected to be over the CWFA by early Monday
as a weak frontal boundary stalls out to our east. Once the boundary
washes out on Tuesday, we'll be left under weak southerly flow from
the Bermuda High that will provide ample chances for scattered to
widespread convection each day/evening. Temperatures should remain
near normal if not a few degrees above each day of the period.

&&

.AVIATION /19Z THURSDAY THROUGH TUESDAY/...
At KCLT: An area of mostly light showers is developing west of the
terminal early this afternoon in advance of an upper air
disturbance. Instability is such that the advertised tempo TSRA may
be a bit overdone, and SHRA may be more appropriate. Nevertheless,
thunder chances are by no means 0, so have continued the tempo for
TSRA from 19-23Z. Will also need to watch for the potential for
additional convection to move off the high terrain later today, as
some guidance is depicting. However, this doesn't seem particularly
plausible at this time. Otherwise, some gusts out of the SW in the
upper teens are possible this afternoon, with winds diminishing this
evening. Barring any convection, VFR conditions are expected through
the period.

Elsewhere: Thunderstorm activity just west of KGMU will pass south
of this terminal and KGSP and east of KAND over the next hour or so,
thus VCTS will be retained at these terminals. However, additional
activity forming upstream of KGMU/KGSP warrants a tempo for the
first couple of hours of the forecast period. There may be a couple
of hours in which the chances for convection fall to less than 20
percent during mid-late afternoon, but will retain VCTS through the
afternoon, as additional convection could move off the high terrain
into the evening. VCTS will also be carried at KAVL, while VCSH is
advertised in the more stable air around KHKY. Otherwise, trends
will be similar to KCLT.

Outlook: A mainly diurnal pattern of showers and thunderstorms will
continue into the weekend. Fog and low stratus will be possible each
morning in the mountain river valleys and also in locations that
receive heavy rainfall from diurnal thunderstorms. A frontal
boundary may stall across the terminal area early next week to keep
the weather active.

Confidence Table...

            19-01Z        01-07Z        07-13Z        13-18Z
KCLT       High 100%     High 100%     High 100%     High 100%
KGSP       High 100%     High 100%     High 100%     High 100%
KAVL       High 100%     High 100%     High  90%     High 100%
KHKY       High 100%     High 100%     High  90%     High 100%
KGMU       High 100%     High 100%     High 100%     High 100%
KAND       High 100%     High 100%     High 100%     High 100%

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

www.weather.gov/gsp/aviation

&&

.CLIMATE...
RECORDS FOR 07-07

               MAX TEMPERATURE         MIN TEMPERATURE
  STATION      HIGH        LOW         HIGH        LOW
  -------  ----------  ----------  ----------  ----------
   KAVL      95 1993     62 1940     70 1948     50 1972
   KCLT     100 1993     65 1979     78 1881     55 1972
                1954
                1930
   KGSP     100 1993     66 1979     75 1977     58 1972
                1986                    1930        1892
                1888

RECORDS FOR 07-08

               MAX TEMPERATURE         MIN TEMPERATURE
  STATION      HIGH        LOW         HIGH        LOW
  -------  ----------  ----------  ----------  ----------
   KAVL      96 1988     63 1909     69 1969     50 1972
   KCLT     101 2012     75 1950     81 1881     58 1892
                2010
   KGSP     101 1986     72 1896     76 2012     57 1913
                1888                    1931

RECORDS FOR 07-09

               MAX TEMPERATURE         MIN TEMPERATURE
  STATION      HIGH        LOW         HIGH        LOW
  -------  ----------  ----------  ----------  ----------
   KAVL      93 1986     64 1979     71 1980     49 1896
   KCLT     101 1986     71 1908     78 1986     57 1891
   KGSP     100 1993     67 1979     78 1930     55 1896
                1986
                1977

&&

.GSP WATCHES/WARNINGS/ADVISORIES...
GA...None.
NC...None.
SC...None.

&&

SYNOPSIS...JPT
NEAR TERM...JDL
SHORT TERM...CDG
LONG TERM...JPT
AVIATION...JDL
CLIMATE...

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
327 PM EDT THU JUL 7 2016

GAZ010-017-NCZ033-048>053-058-059-062>065-081930-
RABUN-HABERSHAM-AVERY-MADISON-YANCEY-MITCHELL-SWAIN-HAYWOOD-BUNCOMBE-
GRAHAM-NORTHERN JACKSON-MACON-SOUTHERN JACKSON-TRANSYLVANIA-
HENDERSON-
327 PM EDT THU JUL 7 2016

THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE MOUNTAINS OF NORTHEAST
GEORGIA AND WESTERN NORTH CAROLINA.

.DAY ONE...THIS AFTERNOON AND TONIGHT.

THUNDERSTORMS ARE IN THE FORECAST TODAY. SOME OF THE THUNDERSTORMS
MAY BE STRONG PRODUCING GUSTY WINDS AS WELL AS CLOUD TO GROUND
LIGHTNING.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY.

..FRIDAY...NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.
..SATURDAY...NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.
..SUNDAY...NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.
..MONDAY...NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.
..TUESDAY...NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.
..WEDNESDAY...NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SKYWARN SPOTTERS ARE REQUESTED TO FORWARD ANY REPORTS OF LARGE
HAIL AND DAMAGING WINDS TO OUR OFFICE.

NCZ035>037-056-057-501>506-081930-
ALEXANDER-IREDELL-DAVIE-CATAWBA-ROWAN-CALDWELL MOUNTAINS-
GREATER CALDWELL-BURKE MOUNTAINS-GREATER BURKE-MCDOWELL MOUNTAINS-
EASTERN MCDOWELL-
327 PM EDT THU JUL 7 2016

THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE NORTHERN PIEDMONT AND
FOOTHILLS OF WESTERN NORTH CAROLINA.

.DAY ONE...THIS AFTERNOON AND TONIGHT.

THUNDERSTORMS ARE IN THE FORECAST TODAY. SOME OF THE THUNDERSTORMS
MAY BE STRONG PRODUCING GUSTY WINDS AS WELL AS CLOUD TO GROUND
LIGHTNING.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY.

..FRIDAY...NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.
..SATURDAY...NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.
..SUNDAY...NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.
..MONDAY...NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.
..TUESDAY...NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.
..WEDNESDAY...NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SKYWARN SPOTTERS ARE REQUESTED TO FORWARD ANY REPORTS OF LARGE
HAIL AND DAMAGING WINDS TO OUR OFFICE.

GAZ018-026-028-029-NCZ068>072-082-507>510-SCZ001>014-019-081930-
STEPHENS-FRANKLIN-HART-ELBERT-CLEVELAND-LINCOLN-GASTON-MECKLENBURG-
CABARRUS-UNION-RUTHERFORD MOUNTAINS-GREATER RUTHERFORD-
POLK MOUNTAINS-EASTERN POLK-OCONEE MOUNTAINS-PICKENS MOUNTAINS-
GREENVILLE MOUNTAINS-GREATER OCONEE-GREATER PICKENS-
GREATER GREENVILLE-SPARTANBURG-CHEROKEE-YORK-ANDERSON-ABBEVILLE-
LAURENS-CHESTER-GREENWOOD-
327 PM EDT THU JUL 7 2016

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTHEAST
GEORGIA...SOUTHERN PIEDMONT AND FOOTHILLS OF WESTERN NORTH
CAROLINA...AND UPSTATE SOUTH CAROLINA.

.DAY ONE...THIS AFTERNOON AND TONIGHT.

THUNDERSTORMS ARE IN THE FORECAST TODAY. SOME OF THE THUNDERSTORMS
MAY BE SEVERE PRODUCING DAMAGING WINDS AND LARGE HAIL AS WELL AS
FREQUENT CLOUD TO GROUND LIGHTNING.

HEAT INDICES WILL EXCEED 100 DEGREES AND APPROACH 105 DEGREES.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY.

..FRIDAY...EXCESSIVE HEAT POSSIBLE. APPARENT TEMPERATURES WILL
EXCEED 100 DEGREES AND APPROACH 105 DEGREES.
..SATURDAY...EXCESSIVE HEAT POSSIBLE. APPARENT TEMPERATURES WILL
EXCEED 100 DEGREES AND APPROACH 105 DEGREES.
..SUNDAY...NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.
..MONDAY...NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.
..TUESDAY...NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.
..WEDNESDAY...NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SKYWARN SPOTTERS ARE REQUESTED TO FORWARD ANY REPORTS OF LARGE
HAIL AND DAMAGING WINDS TO OUR OFFICE.

CDG

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
305 PM EDT THU JUL 07 2016

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0157 PM     TSTM WND DMG     4 E PIEDMONT            34.71N 82.39W
07/07/2016                   GREENVILLE         SC   BROADCAST MEDIA

            A DOWNED TREE WAS REPORTED ON VALLEY BROOK RD.

&&

JMP

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
326 PM EDT THU JUL 7 2016

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0243 PM     TSTM WND DMG     2 N CLINTON             34.51N 81.87W
07/07/2016                   LAURENS            SC   LAW ENFORCEMENT

            SCHP REPORTED A TREE DOWN AT I-385SB AND I-26

0206 PM     TSTM WND DMG     4 NNE FOUNTAIN INN      34.75N 82.16W
07/07/2016                   LAURENS            SC   LAW ENFORCEMENT

            SCHP REPORTED A TREE DOWN AT JC COOPER RD. AND
            BETHANY RD.

&&

JMP

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
353 PM EDT THU JUL 7 2016

SCZ014-072030-
CHESTER SC-
353 PM EDT THU JUL 7 2016

...A STRONG THUNDERSTORM WILL IMPACT SOUTHEASTERN CHESTER COUNTY
UNTIL 430 PM EDT...

AT 352 PM EDT...DOPPLER RADAR WAS TRACKING A STRONG THUNDERSTORM 12
MILES SOUTHEAST OF CHESTER...OR 7 MILES SOUTH OF RICHBURG...MOVING
EAST AT 30 MPH.

LOCATIONS TO BE IMPACTED INCLUDE...
GREAT FALLS...FORT LAWN AND FISHING CREEK RESERVOIR.

DIME SIZE HAIL AND WIND GUSTS UP TO 40 MPH WILL BE POSSIBLE IN THESE
AREAS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS STORM MAY INTENSIFY...SO BE CERTAIN TO MONITOR LOCAL RADIO AND
TV STATIONS...AS WELL AS LOCAL CABLE TV OUTLETS FOR ADDITIONAL
INFORMATION AND POSSIBLE WARNINGS FROM THE NATIONAL WEATHER SERVICE.

&&

LAT...LON 3467 8089 3465 8089 3464 8090 3462 8089
      3460 8089 3458 8088 3455 8087 3454 8088
      3455 8097 3456 8113 3471 8110 3470 8086
TIME...MOT...LOC 1952Z 279DEG 26KT 3461 8103

ARK

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
402 PM EDT THU JUL 07 2016

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0244 PM     TSTM WND DMG     5 NE CLINTON            34.53N 81.80W
07/07/2016                   LAURENS            SC   COUNTY OFFICIAL

            TREE DOWN OFF RIDGE RD NORTHEAST OF CLINTON, SC.

&&

JPT

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
435 PM EDT THU JUL 7 2016

NCZ071-072-072100-
CABARRUS NC-MECKLENBURG NC-
435 PM EDT THU JUL 7 2016

...A STRONG THUNDERSTORM WILL IMPACT NORTHWESTERN MECKLENBURG AND
CABARRUS COUNTIES UNTIL 500 PM EDT...

AT 434 PM EDT...DOPPLER RADAR WAS TRACKING A STRONG THUNDERSTORM NEAR
HUNTERSVILLE...OR NEAR CORNELIUS...MOVING EAST AT 35 MPH.

LOCATIONS TO BE IMPACTED INCLUDE...
HUNTERSVILLE...KANNAPOLIS...DOWNTOWN CONCORD...WEST
CONCORD...CORNELIUS... DAVIDSON...HARRISBURG...MT
PLEASANT...CHARLOTTE MOTOR SPEEDWAY AND CODDLE CREEK RESERVOIR.

HALF INCH HAIL AND WIND GUSTS UP TO 40 MPH WILL BE POSSIBLE IN THESE
AREAS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

GUSTY WINDS CAN BLOW DOWN TREES THAT ARE DEAD...OR THAT HAVE WEAKENED
ROOT SYSTEMS. OUTDOOR FURNITURE AND SIMILAR ITEMS CAN BE TOSSED
AROUND IF NOT ANCHORED. SEEK SHELTER INDOORS.

TORRENTIAL RAINFALL MAY FLOOD AREAS WITH POOR DRAINAGE...SUCH AS
DITCHES AND UNDERPASSES. AVOID THESE AREAS AND DO NOT CROSS FLOODED
ROADS. WATER LEVELS OF SMALL STREAMS MAY ALSO RISE RAPIDLY. SEEK
HIGHER GROUND IF THREATENED BY FLOOD WATERS. DO NOT DRIVE ACROSS
FLOODED ROADS.

&&

LAT...LON 3524 8048 3540 8095 3550 8093 3551 8091
      3550 8039
TIME...MOT...LOC 2034Z 285DEG 31KT 3547 8084

ARK

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
439 PM EDT THU JUL 7 2016

NCZ068>071-072115-
CLEVELAND NC-GASTON NC-MECKLENBURG NC-LINCOLN NC-
439 PM EDT THU JUL 7 2016

...STRONG THUNDERSTORMS WILL IMPACT MECKLENBURG...GASTON...
SOUTHEASTERN CLEVELAND AND SOUTHEASTERN LINCOLN COUNTIES UNTIL 515 PM
EDT...

AT 438 PM EDT...DOPPLER RADAR INDICATED STRONG THUNDERSTORMS ALONG A
LINE EXTENDING FROM 8 MILES SOUTHEAST OF LINCOLNTON TO 4 MILES EAST
OF SHELBY...AND MOVING SOUTHEAST AT 25 MPH.

LOCATIONS TO BE IMPACTED INCLUDE... GASTONIA...UPTOWN
CHARLOTTE...SHELBY...HUNTERSVILLE...CENTRAL CHARLOTTE... AND KINGS
MOUNTAIN.

PEA SIZE HAIL...WIND GUSTS UP TO 40 MPH AND VERY HEAVY RAINFALL RATES
UP TO 2 INCHES PER HOUR WILL BE POSSIBLE IN THESE AREAS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

GUSTY WINDS CAN BLOW DOWN TREES THAT ARE DEAD...OR THAT HAVE WEAKENED
ROOT SYSTEMS. OUTDOOR FURNITURE AND SIMILAR ITEMS CAN BE TOSSED
AROUND IF NOT ANCHORED. SEEK SHELTER INDOORS.

TORRENTIAL RAINFALL MAY FLOOD AREAS WITH POOR DRAINAGE...SUCH AS
DITCHES AND UNDERPASSES. AVOID THESE AREAS AND DO NOT CROSS FLOODED
ROADS. WATER LEVELS OF SMALL STREAMS MAY ALSO RISE RAPIDLY. SEEK
HIGHER GROUND IF THREATENED BY FLOOD WATERS. DO NOT DRIVE ACROSS
FLOODED ROADS.

&&

LAT...LON 3509 8092 3511 8094 3504 8104 3506 8106
      3509 8106 3511 8103 3515 8105 3517 8146
      3525 8159 3547 8110 3532 8068 3527 8067
      3523 8059
TIME...MOT...LOC 2038Z 299DEG 22KT 3541 8112 3526 8146

ARK