Special Weather Statement, NWS Greenville-Spartanburg, SC

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
732 PM EDT Tue Mar 21 2017

.SYNOPSIS...
A cold front will move through the area later tonight, increasing
the chances for widespread showers and thunderstorms. A few of the
thunderstorms could be severe. Cooler air will return behind the
front to end the work week before another frontal system approaches
the area next weekend.

&&

.NEAR TERM /THROUGH WEDNESDAY/...
730 PM EDT Update...Strong/severe storms with big hail arnd the GSP
area tonight. Reports of car windows smashed and golf ball size or
greater hail. These storms have trained down from the escarpment of
nrn G-ville Co and there are some concerns with high water levels
across local streams as well. Will investigate for possible flood
advisories or SPSs. Strong h5 s/w noted crossing into nrn GA and ern
TN attm will track across the CWFA late tonight thru the early
morning hrs. More strong to severe storms are probable with this
feature producing damaging winds and large hail once again.

500 PM EDT Update...A couple Upstate svr storms are beginning to
break the thermal cap and slowly advance south ahead of a sfc bndry.
Expect isol stg/svr activity to remain across NE GA and the Upstate
through 00z. An advancing acute h5 s/w will enhance activity from
the west and cross the watch area into the late evening. The watch
may need to be expanded east later on.

As of 215 PM: A nearly stationary front remains across the northern
tier of NC and TN attm; it is difficult to pinpoint the front in
many areas, but it is clear VA and KY are north of the front. At any
rate, an amplified upper ridge will move into the Plains states this
evening, and in response high pressure will shift into the Great
Lakes region, driving the front south through our area tonight.

This afternoon, south of the front, warm and seasonably humid
conditions will be present. Mid-level lapse rates are rather strong,
and accordingly forecast CAPE values range from 750-1000 J/kg over
the NE CWFA to nearly 2000 J/kg over parts of SW NC and NE GA. Most
prog soundings continue to feature at least a small cap until around
21z, and this is reflected in reflectivity/QPF output from the CAMs,
which is minimal until then. 0-6km bulk shear values will be on the
order of 30-35 kt around peak heating, and we continue to expect
storms to organize to some degree. SPC has outlined an Enhanced
Risk centered to our west, but extending into a small portion
of our northeast GA territory; this is surrounded by a narrow
Slight Risk region. At least the Enhanced area will receive the
effects of a compact shortwave during the late afternoon hours,
and models are a bit more aggressive in pushing the front south
thru TN than they are over our area. Also of note, meso model runs
have tended to show a forward-propagating cluster developing in the
Tennessee Valley and tracking east this evening. This may present
a secondary threat to our western areas in addition to that posed
by the greater afternoon instability. Our entire CWFA continues
to be included in a Marginal Risk where the threats appear largely
the same, but the coverage will be lower.

Remnant stratiform precip associated with the decayed MCS is
expected to cross the area overnight, perhaps with a few isolated
rumbles of thunder but otherwise just light rainfall. With any
broad frontal boundary progged to push through in the early morning
hours, I am somewhat cautious about advertising a total "scouring"
of low-level moisture. However, essentially all guidance sources,
including MOS, depict the low clouds pushing out by daybreak, and
cooler and drier conditions lasting thru Wednesday. GFS still tries
to develop a little instability over NE GA, but currently this looks
to be an outlier. All precip mention has been dropped. Sunshine
and gradual downsloping should permit high temps near normal.

&&

.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
As of 2pm EDT Tuesday:  GFS and EC models in good agreement on
synoptic pattern transitioning Wednesday evening to Friday from
northwesterly flow with dry, cool low-level advection to a ridge
centered over the CWA by Friday afternoon.  Dewpoints begin to
improve Friday afternoon as surface high pressure center moves
eastward off the coast and low-level flow veers from easterly to
southeasterly, beginning the southeasterly advection of
moisture into the area.

With a dry boundary layer and ridging aloft, there will be little
chance for precipitation Wednesday night through Friday, with only
an outside chance for some orographic-related showers in far western
parts of the CWA.  Main issue will be chances for frost/freeze
Thursday and Friday mornings.  Current lows show freeze possible
with frost likely for western parts of North Carolina, with less
potential for Piedmont areas.  Drier air and few clouds northeast of GSP
leads to lower forecast lows to the northeast with CLT possibly
reaching low to mid 30s Thursday morning and mid to upper 30s Friday
morning.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
As of 205 PM EDT Tuesday: the medium range fcst picks up at 00z on
Saturday with upper ridging centered over the SE CONUS and a
southern stream closed upper low moving across the southern plains.
Over the next 24 to 48 hrs, the low will approach the fcst area and
as it does, it will lift northward and up over the ridge. As it
does, it's also expected to deamplify and open up as it rides up the
ridge. As we move into early next week, another H5 shortwave will
approach the CWFA from the west. It also appears to deamplify as it
approaches the CWFA.

At the sfc, broad high pressure will be centered well offshore with
moist SLY flow over the region. By early Sunday, a vigorous low will
lift NE towards the Great Lakes and push a moist warm front over the
CWFA. The cold front associated with the low, looks like it will
largely washout as it lays across our northern fringe early Monday.
As we move into Tuesday, another sfc low follows a similar track
towards the Great Lakes and brings another cold front to our
doorstep by the end of the period. As for the sensible wx, POPs
steadily ramp up from the west on Sat with likely POPs over half of
the CWFA by Sunday morning. Some drying is expected on Monday,
however POPs increase again on Tuesday with the approach of the next
frontal system. Temps start out above normal and remain above normal
thru the period.

&&

.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
At KCLT and elsewhere: Showers and strong to severe thunderstorms will cross
the SC sites as well as KCLT thru the overnight. Large hail and
damaging winds could occur at any site thru 09z. CIGS and VSBY are
generally remaining in the VFR range outside of the storms...with
MVFR/IFR conds and erratic gusty winds underneath the individual
cells. The mtn sites should remain out of the strong activity with
isol general tstms possible overnight. Skies clear up around
daybreak with winds shifting n/ly to nne/ly.

Outlook: Low level moisture starts to lift back north and deepen by
Thursday, keeping chances of showers and low cigs into the weekend.

Confidence Table...

            23-05Z        05-11Z        11-17Z        17-18Z
KCLT       High 100%     High  89%     High 100%     High 100%
KGSP       High 100%     High 100%     High 100%     High 100%
KAVL       High 100%     High  94%     High 100%     High 100%
KHKY       High 100%     High 100%     High 100%     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

&&

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

&&

SYNOPSIS...JPT
NEAR TERM...SBK/Wimberley
SHORT TERM...WJM
LONG TERM...JPT
AVIATION...SBK

Hazardous Weather Outlook
National Weather Service Greenville-Spartanburg SC
337 PM EDT Tue Mar 21 2017

GAZ010-017-018-026-028-029-NCZ051-058-059-062>064-SCZ001>007-010>013-
019-221945-
Rabun-Habersham-Stephens-Franklin-Hart-Elbert-Swain-Graham-
Northern Jackson-Macon-Southern Jackson-Transylvania-
Oconee Mountains-Pickens Mountains-Greenville Mountains-
Greater Oconee-Greater Pickens-Greater Greenville-Spartanburg-
Anderson-Abbeville-Laurens-Union-Greenwood-
337 PM EDT Tue Mar 21 2017

...SEVERE THUNDERSTORM WATCH 76 IN EFFECT UNTIL 11 PM EDT THIS
EVENING...

This Hazardous Weather Outlook is for northeast Georgia, western
North Carolina and upstate South Carolina.

.DAY ONE...This Afternoon and Tonight.

Please listen to NOAA Weather Radio or go to weather.gov on the
Internet for more information about the following hazards.

   Severe Thunderstorm Watch.

Showers and thunderstorms develop across the area this afternoon and
continue into the evening. A few of these storms could become severe
producing damaging winds and large hail.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday.

..Wednesday...No hazardous weather is expected at this time.
..Thursday...No hazardous weather is expected at this time.
..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.

.SPOTTER INFORMATION STATEMENT...

None.

NCZ033-048>050-052-053-065-501-503-505-507-509-221945-
Avery-Madison-Yancey-Mitchell-Haywood-Buncombe-Henderson-
Caldwell Mountains-Burke Mountains-McDowell Mountains-
Rutherford Mountains-Polk Mountains-
337 PM EDT Tue Mar 21 2017

This Hazardous Weather Outlook is for western North Carolina.

.DAY ONE...This Afternoon and Tonight.

Showers and thunderstorms develop across the area this afternoon and
continue into the evening. A few of these storms could become severe
producing damaging winds and large hail.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday.

..Wednesday...No hazardous weather is expected at this time.
..Thursday...No hazardous weather is expected at this time.
..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.

.SPOTTER INFORMATION STATEMENT...

None.

SCZ008-221945-
Cherokee-
337 PM EDT Tue Mar 21 2017

...SEVERE THUNDERSTORM WATCH 76 IN EFFECT UNTIL 11 PM EDT THIS
EVENING...

This Hazardous Weather Outlook is for upstate South Carolina.

.DAY ONE...This Afternoon and Tonight.

Please listen to NOAA Weather Radio or go to weather.gov on the
Internet for more information about the following hazards.

   Severe Thunderstorm Watch.

Showers and thunderstorms develop across the area this afternoon and
continue into the evening. A few of these storms could become severe
producing damaging winds and large hail.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday.

..Wednesday...No hazardous weather is expected at this time.
..Thursday...Frost/freeze possible. Cold high pressure builds into
the area with temperatures falling into the lower to mid 30s. This
will create the potential for frosty or freezing conditions.
..Friday...Frost/freeze possible. Cold high pressure remains over
the area with temperatures in the mid 30s. This will create the
potential for frosty conditions.
..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.

.SPOTTER INFORMATION STATEMENT...

None.

NCZ035>037-056-057-068>072-082-502-504-506-508-510-SCZ009-014-221945-
Alexander-Iredell-Davie-Catawba-Rowan-Cleveland-Lincoln-Gaston-
Mecklenburg-Cabarrus-Union-Greater Caldwell-Greater Burke-
Eastern McDowell-Greater Rutherford-Eastern Polk-York-Chester-
337 PM EDT Tue Mar 21 2017

This Hazardous Weather Outlook is for piedmont North Carolina,
western North Carolina and upstate South Carolina.

.DAY ONE...This Afternoon and Tonight.

Showers and thunderstorms develop across the area this afternoon and
continue into the evening. A few of these storms could become severe
producing damaging winds and large hail.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday.

..Wednesday...No hazardous weather is expected at this time.
..Thursday...Frost/freeze possible. Cold high pressure builds into
the area with temperatures falling into the lower to mid 30s. This
will create the potential for frosty or freezing conditions.
..Friday...Frost/freeze possible. Cold high pressure remains over
the area with temperatures in the mid 30s. This will create the
potential for frosty conditions.
..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.

.SPOTTER INFORMATION STATEMENT...

None.

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
851 PM EDT TUE MAR 21 2017

NCZ062-220130-
Macon NC-
851 PM EDT TUE MAR 21 2017

...STRONG THUNDERSTORMS WILL IMPACT MACON COUNTY UNTIL 930 PM EDT...

At 850 PM EDT, Doppler radar indicated strong thunderstorms along a
line extending from 12 miles southwest of Bryson City to 7 miles west
of Franklin to 10 miles northwest of Clayton, and moving east at 35
mph.

Locations to be impacted include...
Franklin, Highlands, Nantahala Lake, Ellijay, Burningtown, Kyle,
Otto, Rainbow Springs, Wayah Bald and Cowee.

Wind gusts up to 40 mph and pea size hail will be possible in these
areas.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

The combination of gusty winds and saturated soil conditions will
cause scattered trees and power lines to fall. Seek shelter inside an
interior room.

&&

A severe thunderstorm watch remains in effect until 1100 PM EDT for
northeastern Georgia...and western North Carolina.

LAT...LON 3519 8371 3520 8373 3523 8369 3526 8370
      3528 8367 3530 8346 3533 8343 3533 8334
      3523 8329 3524 8322 3516 8322 3509 8315
      3506 8317 3500 8311 3500 8352 3502 8352
      3513 8362 3514 8365 3515 8365 3515 8374
TIME...MOT...LOC 0050Z 260DEG 30KT 3528 8357 3514 8351 3500 8352

HG

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
852 PM EDT TUE MAR 21 2017

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

0840 PM     HAIL             4 WSW HARRISBURG        35.31N 80.74W
03/21/2017  E1.75 INCH       MECKLENBURG        NC   PUBLIC

            GLOF BALL SIZE HAIL AT UNC CHARLOTTE

&&

LVISIN

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
852 PM EDT TUE MAR 21 2017

NCZ082-220115-
Union NC-
852 PM EDT TUE MAR 21 2017

...A STRONG THUNDERSTORM WILL IMPACT NORTHEASTERN UNION COUNTY UNTIL
915 PM EDT...

At 852 PM EDT, Doppler radar was tracking a strong thunderstorm 14
miles northeast of Monroe, or 9 miles east of Unionville, moving east
at 10 mph.

Locations to be impacted include...
New Salem.

Wind gusts up to 40 mph and dime size hail will be possible in these
areas.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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.

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 3502 8030 3501 8041 3516 8045 3516 8044
      3517 8042 3516 8041 3518 8037 3517 8036
      3518 8033 3517 8032 3519 8030 3520 8028
TIME...MOT...LOC 0052Z 256DEG 9KT 3512 8035

MOORE

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
857 PM EDT TUE MAR 21 2017

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

0843 PM     HAIL             2 S DAVIDSON            35.47N 80.85W
03/21/2017  E1.00 INCH       MECKLENBURG        NC   PUBLIC

            QUARTER SIZE HAIL NEAR DAVIDSON

&&

LVISIN

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
900 PM EDT TUE MAR 21 2017

SCZ012-019-220145-
Laurens SC-Greenwood SC-
900 PM EDT TUE MAR 21 2017

...A STRONG THUNDERSTORM WILL IMPACT SOUTH CENTRAL LAURENS AND
GREENWOOD COUNTIES UNTIL 945 PM EDT...

At 900 PM EDT, Doppler radar was tracking a strong thunderstorm 7
miles southeast of Greenwood, or near Ninety Six Historic Site,
moving east at 30 mph.

Locations to be impacted include...
Greenwood, Ninety Six, Lake Greenwood, Greenwood State Park, Ninety
Six Historic Site, Kirksey, Dyson, Callison, Epworth and Coronaca.

Wind gusts up to 40 mph and dime size hail will be possible in these
areas.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Dime to nickel size hail can cause considerable damage to vehicles.
Consider moving vehicles to a covered storage area before the storm
arrives.

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.

&&

A severe thunderstorm watch remains in effect until 1100 PM EDT for
Upstate South Carolina.

LAT...LON 3398 8205 3399 8215 3397 8218 3399 8221
      3402 8225 3417 8219 3429 8206 3423 8192
      3420 8194 3418 8191 3415 8190 3413 8187
      3410 8190 3409 8192 3397 8201 3396 8205
TIME...MOT...LOC 0100Z 279DEG 26KT 3413 8205

MOORE

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
901 PM EDT TUE MAR 21 2017

GAZ017-018-026-028-029-220130-
Elbert GA-Hart GA-Franklin GA-Stephens GA-Habersham GA-
901 PM EDT TUE MAR 21 2017

...STRONG THUNDERSTORMS WILL IMPACT FRANKLIN...STEPHENS...ELBERT...
SOUTHEASTERN HABERSHAM AND HART COUNTIES UNTIL 930 PM EDT...

At 900 PM EDT, Doppler radar indicated strong thunderstorms along a
line extending from 6 miles southeast of Clarkesville to 5 miles west
of Jefferson, and moving southeast at 35 mph.

Locations to be impacted include...
Toccoa, Elberton, Hartwell, Carnesville, Royston, Reed Creek,
Lavonia, Gumlog, Bowman and Canon.

Wind gusts up to 40 mph, half inch hail and very heavy rainfall rates
up to 2 inches per hour will be possible in these areas.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

The combination of gusty winds and saturated soil conditions will
cause scattered trees and power lines to fall. Seek shelter inside an
interior room.

&&

A severe thunderstorm watch remains in effect until 1100 PM EDT for
northeastern Georgia...and Upstate South Carolina.

LAT...LON 3401 8294 3417 8310 3423 8308 3427 8312
      3424 8317 3426 8330 3423 8335 3433 8339
      3445 8339 3449 8349 3460 8344 3465 8328
      3461 8316 3448 8304 3448 8288 3437 8284
      3427 8275 3415 8272 3409 8264 3399 8258
TIME...MOT...LOC 0100Z 315DEG 44KT 3453 8347 3411 8366

HG