Special Weather Statement, NWS Greenville-Spartanburg, SC

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
635 AM EDT THU AUG 4 2016

.SYNOPSIS...
A cool and moist wedge of high pressure will persist atop the region
today, lingering into Friday. Another frontal boundary is
expected to enter the region over the weekend, keeping higher than
normal rainfall chances in the forecast through early next week.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 630 AM...shallow-topped convection continues to develop and
decay slowly in the moist easterly low level flow across the area.
Heaviest rainfall so far this morning has been along and near the
Blue Ridge escarpment in both Carolinas and NE GA. Precip will
continue across these areas through the morning given the good low
level convergence and instability. The strong moist southeasterly
low level flow remains across the area today. A relatively strong
short wave drops into the area from the NW. There is also a weak
upper jet moving in to provide some upper level divergence which was
missing on Wednesday. PW values are forecast to remain above 2
inches today with weak instability across the area as well. The mid
level flow turns more southerly in response to the short wave.
However, steering flow will still be weak. The shallow convection
should still have very  efficient rain rates. Therefore, still
expect areas of heavy rainfall with the potential for training and
anchoring of cells through the day. Since heavy rainfall has fallen
outside of the previous watch area and additional heavy rainfall
could develop in almost any location, have expanded the flash flood
watch to include all of NE GA and the Upstate along with all of the
Blue Ridge escarpment in NC. Highs will be below normal with the
clouds and rain.

The low level flow finally turns more southwesterly late tonight
ending the strong moist upslope flow. Precip coverage should slowly
decrease through the night as well. Will keep the watch in place
through 7 AM Friday since it may be well after midnight before the
heavy rain potential ends. Lows should be a little above normal.

&&

.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
As of 230 AM EDT Thursday:  The short term fcst period initializes
on Friday morning amidst the approach of a weak disturbance aloft,
embedded within a broad H5 ridge that dominates the southern
CONUS.  At the surface, high pressure anchored over New England
looks to prevail yielding continued moist/easterly llv flow.
Pattern evolution through Friday into Saturday features a break
down of the northeast parent high thanks to a digging H5 trof
into the Great Lakes region.  With that, the wedge like pattern
will erode into/through midday allowing for veered llv flow
and thus lower chances for upsloping, as well relief from the
elevated pwats.  All said, convection will initiate amidst broad
synoptic lift thanks to the weak H5 wave across the region, as
well as marginal instability.  Meanwhile, a cold front will be
exiting the mid/upper MS river valley, sliding east into the OH
river valley late Friday evening.

On Saturday, guidance favors further veering of llv flow thanks
to the now dominant subtropical ridge which will in turn advect
the persistently moist airmass atop northeast GA and the western
Carolinas to the east allowing for some drying, especially over
the western tier of the fcst area.  The a fore mentioned front
then comes into the picture late on Saturday into the overnight
hours of Sunday morning with little fan fare.

Thus the fcst on Friday will feature high end chance pops
across the low terrain with likely levels over the mtns, falling
overnight into Saturday morning to slight chances, and low end
chance levels respectively.  Pops increase diurnally on Saturday to
widespread chances, with the highest levels favored along the mtns,
remaining mentionable albeit lower overnight into Sunday morning.
Temperatures through the period will moderate from below normal
levels on Friday, to above normal on Saturday.

&&

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
As of 245 AM EDT Thursday:  The medium range fcst period kicks
off on Sunday morning as broad H5 troffing slides east across New
England, while ridging builds over the southern plains.  At the
surface, a cold front looks to advect through the region from the
north on Sunday as a broad region of high pressure slides across the
Great Lakes, stretching southward into the central Appalachians.
Guidance continues to indicate the potential for stalling of said
front in the vicinity of the fcst area on Monday, while another
wedge like pattern builds as the sprawling surface high sets up over
the northeast.  Overall, this pattern looks rather wet as moist
upsloping/upglide is evident, all lasting into/through Tuesday
afternoon warranting above normal pops during this timeframe.
Beyond that the pattern looks increasingly diurnal as the wedge
like feature retreats and the subtropical ridge prevails leading to
the return of moist and likewise unstable air, thus generally climo
pops were favored.  Temperatures on Sunday will be at or just above
normal levels before cooling nearly 8-10 degrees on Monday/Tuesday
behind the front amongst the cooler/wetter wedge.  Afterward,
gradual warming and thus a return to near normal is favored.

&&

.AVIATION /12Z THURSDAY THROUGH MONDAY/...
At KCLT, a low level easterly flow persists across the area through
the day. Expect IFR cig to start with only a slow improvement to lo
VFR by early afternoon. Do not expect any VSBY restrictions unless a
shower or storm moves across the airfield. Expect a chance of
thunderstorms from afternoon into early evening as the boundary
layer destabilizes, but SHRA could develop at any time through the
period. Will see a return to MVFR then IFR cig overnight. ESE winds
become ENE this morning and continue through the period. However,
cannot rule out a brief shift back to ESE from time to time.

Elsewhere, similar conditions to KCLT. SHRA chances are higher over
the rest of the area. KAVL will see light S wind.

Outlook: Moisture will continue on easterly flow into Friday with
associated showers and thunderstorms developing - especially in the
afternoon and evening. Restrictions will be possible with any
afternoon/evening convection as well as each morning in the mountain
valleys where fog and low stratus are likely, but will be possible
outside of the mountains as well. Some drying develops Saturday as
flow becomes southwesterly. A frontal boundary drops into the area
Sunday and lingers into Monday.

Confidence Table...

            10-16Z        16-22Z        22-04Z        04-06Z
KCLT       Med   67%     High  80%     High 100%     High 100%
KGSP       Med   75%     High  92%     High 100%     High 100%
KAVL       Med   75%     High  95%     High  95%     Low   51%
KHKY       Low   42%     Low   54%     High  97%     Med   79%
KGMU       High  82%     High  95%     High 100%     High 100%
KAND       Med   61%     High  85%     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...Flash Flood Watch through Friday morning for GAZ010-017-018-
     026-028-029.
NC...Flash Flood Watch through Friday morning for NCZ033-035>037-
     049-050-053-056-057-062>065-068>072-082-501>510.
SC...Flash Flood Watch through Friday morning for SCZ001>014-019.

&&

SYNOPSIS...CDG/JPT
NEAR TERM...RWH
SHORT TERM...CDG
LONG TERM...CDG
AVIATION...RWH

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
432 AM EDT THU AUG 4 2016

GAZ010-017-018-026-028-029-NCZ033-035>037-049-050-053-056-057-
062>065-068>072-082-501>510-SCZ001>014-019-050845-
RABUN-HABERSHAM-STEPHENS-FRANKLIN-HART-ELBERT-AVERY-ALEXANDER-
IREDELL-DAVIE-YANCEY-MITCHELL-BUNCOMBE-CATAWBA-ROWAN-MACON-
SOUTHERN JACKSON-TRANSYLVANIA-HENDERSON-CLEVELAND-LINCOLN-GASTON-
MECKLENBURG-CABARRUS-UNION-CALDWELL MOUNTAINS-GREATER CALDWELL-
BURKE MOUNTAINS-GREATER BURKE-MCDOWELL MOUNTAINS-EASTERN MCDOWELL-
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-
432 AM EDT THU AUG 4 2016

...FLASH FLOOD WATCH IN EFFECT THROUGH FRIDAY MORNING...

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

.DAY ONE...TODAY AND TONIGHT.

PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV ON THE
INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS.

   FLASH FLOOD WATCH.

.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 FLASH
FLOODING TO OUR OFFICE.

NCZ048-051-052-058-059-050845-
MADISON-SWAIN-HAYWOOD-GRAHAM-NORTHERN JACKSON-
432 AM EDT THU AUG 4 2016

THIS HAZARDOUS WEATHER OUTLOOK IS FOR WESTERN NORTH CAROLINA.

.DAY ONE...TODAY AND TONIGHT.

SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS ARE EXPECTED TODAY
AND TONIGHT. THE PRIMARY THREATS WITH ANY OF THESE HEAVIER THUNDERSTORMS
WILL BE HEAVY RAINFALL AND 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 FLASH
FLOODING TO OUR OFFICE.

CDG

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
744 AM EDT THU AUG 4 2016

NCZ508-510-041245-
GREATER RUTHERFORD NC-EASTERN POLK NC-
744 AM EDT THU AUG 4 2016

...AN AREA OF HEAVY RAIN WILL IMPACT RUTHERFORD AND POLK COUNTIES
UNTIL 845 AM EDT...

AT 742 AM EDT...DOPPLER RADAR INDICATED THE LEADING EDGE OF AN AREA
OF HEAVY RAIN ALONG A LINE EXTENDING FROM 6 MILES SOUTHEAST OF
MARION TO 6 MILES NORTHEAST OF COLUMBUS. THIS HEAVY RAIN WAS NEARLY
STATIONARY.

LOCATIONS TO BE IMPACTED INCLUDE... FOREST
CITY...RUTHERFORDTON...COLUMBUS...SPINDALE...TRYON...BOSTIC...GREEN
HILL...SUNSHINE...HARRIS AND GREEN CREEK.

VERY HEAVY RAINFALL RATES UP TO 2 INCHES PER HOUR WILL BE POSSIBLE
IN THESE AREAS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THE RAINFALL 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 3560 8172 3558 8169 3518 8188 3520 8226
      3522 8227 3536 8223 3543 8216 3554 8208
      3554 8203 3555 8200 3552 8197 3554 8185
      3558 8182 3558 8180 3561 8176
TIME...MOT...LOC 1142Z 265DEG 2KT 3560 8197 3532 8213

TDP

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
806 AM EDT THU AUG 4 2016

GAZ010-017-NCZ062-SCZ001-041300-
RABUN GA-HABERSHAM GA-MACON NC-OCONEE MOUNTAINS SC-
806 AM EDT THU AUG 4 2016

...AN AREA OF HEAVY RAIN WILL IMPACT NORTHERN HABERSHAM...RABUN...
SOUTHEASTERN MACON AND NORTHWESTERN OCONEE COUNTIES UNTIL 900 AM
EDT...

AT 805 AM EDT...DOPPLER RADAR INDICATED THE LEADING EDGE OF AN AREA
OF HEAVY RAIN ALONG A LINE EXTENDING FROM 8 MILES SOUTH OF FRANKLIN
TO NEAR CLARKESVILLE. THIS HEAVY RAIN WAS NEARLY STATIONARY.

LOCATIONS TO BE IMPACTED INCLUDE...
CLAYTON...HIGHLANDS...MOUNTAIN CITY...TIGER...DILLARD...SKY VALLEY...
TALLULAH FALLS...LAKEMONT...LAKE RABUN AND MOCCASIN CREEK STATE PARK.

VERY HEAVY RAINFALL RATES UP TO 2 INCHES PER HOUR WILL BE POSSIBLE
IN THESE AREAS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THESE HEAVY RAIN 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 3494 8360 3495 8355 3499 8355 3500 8348
      3500 8352 3502 8352 3504 8356 3509 8358
      3513 8318 3511 8318 3508 8314 3506 8317
      3504 8313 3501 8312 3465 8327 3469 8334
      3467 8337 3465 8338 3465 8361
TIME...MOT...LOC 1205Z 190DEG 4KT 3506 8342 3461 8349

TDP