Flash Flood Warning 66, NWS Greenville-Spartanburg, SC

079 
WGUS72 KGSP 111851
FFSGSP

Flash Flood Statement
National Weather Service Greenville-Spartanburg SC
151 PM EST Wed Nov 11 2020

NCC045-071-111901-
/O.CAN.KGSP.FF.W.0066.000000T0000Z-201111T2100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Cleveland NC-Gaston NC-
151 PM EST Wed Nov 11 2020

...FLASH FLOOD WARNING FOR SOUTHEASTERN CLEVELAND AND NORTHWESTERN 
GASTON COUNTIES HAS BEEN REPLACED WITH A FLOOD ADVISORY...

Heavy rain from this morning has departed Cleveland County and the 
resultant flooding is subsiding. Therefore, the Flash Flood Warning 
will be cancelled and replaced with a Flood Advisory for residual 
nuisance flooding.  Please continue to obey all barricades even if 
water is no longer covering the road and avoid flooded roadways.

LAT...LON 3518 8168 3539 8162 3549 8148 3542 8145
      3540 8131 3531 8136 3517 8140

$$

JMP

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
656 AM EST Wed Nov 11 2020

.SYNOPSIS...
A plume of deep tropical moisture ahead of a slow moving cold front
will affect the region today and tonight, allowing for widespread
rain. The front is expected to move into the mountains tonight and
then slowly east across the Piedmont of the Carolinas Thursday and
Thursday night. Dry air may move into the region for Friday and into
Saturday, with Tropical Storm Eta remaining well to our southeast.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 650 AM: The axis of the atmospheric river has set up across
the eastern third of the forecast area, with the I-77 corridor
expected to get some heavy downpours and possibly minor flooding
this morning per latest radar trends. A lull in the precip, as
expected, is working into the western half of the area. But even
within that, spotty light rain continues to develop. Areas of fog
are developing within this lull as well, but dense fog doesn't
look widespread enough for an advisory.

Otherwise, guidance is in good agreement that this will pivot east
to the eastern edge of the forecast area by late morning, as a high
pressure system nudges east. The 850 mb flow will weaken and veer
to more S/SWLY today, which will result in weaker low-level forcing
and less of an upslope component along the Blue Ridge. With that
said, PWATs will only tick down slightly from 2.0-2.1" to 1.75-2.0"
range (still 2-3x normal). Meanwhile, a series of shortwaves will
ride along SWLY flow aloft and further erode the North Atlantic
ridge. Height falls atop the FA will support some destabilization
and increasing upper support for another round of convection. The
models generally have a relative lull in precip coverage and
intensity this morning thru early aftn. Then, with peak heating
and a sfc cold front pushing in from the west, a second round of
convection is expected to develop. There will be some low-level
convergence along an axis that is more parallel with the SWLY,
which could set up a band of heavy rainfall somewhere across
the forecast area. The CAMs favor the Piedmont from roughly
the Greenville/Spartanburg area NE thru the NW NC Piedmont. The
operational models are in greater disagreement on this, with the
NAM and GFS favoring western and central NC mountains, while
the EC and Canadian are more muted. It's possible the front
gets hung up over the NC mountains this evening. But the better
instability and PWATs will be east. So given the trends and after
collaboration with neighboring offices, have expanded the Flood
Watch east to include all the NC Piedmont and the northern tier
of the Upstate thru Thursday. Areas further south haven't had as
much rain so far early this morning, and are not in the axis of
heaviest QPF going forward. The other concern today is any severe
threat, given the expected instability this aftn. Fortunately,
it remains low, as mid-level lapse rates remain weak, and there
will be a lot of cloud cover thru the day. Even if we end up more
unstable than expected, bulk shear actually weakens today, as the
LLJ axis shifts east and flow is more unidirectional. So expect
just general thunder today. Temps will be about 10-15 deg above
normal today, and it will feel humid, as dewpts reach the lower
70s across most of the Piedmont.

Tonight, the heavy rain concerns will continue thru the
night. Unseasonably humid air and continued WAA will keep temps in
the 60s overnight. Min temps may be as much as 25 deg above normal.

&&

.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
As of 153 AM EST Wednesday: As we suspected it might be...the
forecast for the end of the work week is in a state of flux,
due to the ongoing uncertainty and changes in the expected track
of Eta. There is remarkable agreement now with the position of
a surface boundary on the east side of the mtns at daybreak on
Thursday that will keep a precip probability and QPF gradient
across the forecast area. There is also decent agreement that the
effective boundary will push off to the east during the day. This
will keep the I-85 corridor and the Charlotte metro area under
an elevated threat for heavy rain, but it remains to be seen
if enough forcing will linger east of the mountains to produce
enough rainfall to cause problems. The higher precip probs over
the east will diminish thru the day. Meanwhile, drier air should
start filtering into the mtns during the day that should greatly
diminish the flash flood potential early in the day. Lingering low
level moisture will keep some weak instability across the region
in the wake of the effective boundary, so scattered convection
will be retained mainly east of the mtns. The rain chance will
linger through Thursday night and into Friday morning east of
the mtns in deference to the GFS solution and the possibility
that weak forcing and sufficient moisture will remain. There is
growing consensus that Eta will move along a northeasterly track
that takes the storm well to our southeast, and that a flat upper
ridge will be able to push a sfc high to our NW into the region
on Friday and Friday night. This would allow much drier air to
push in from the north. This trend will be followed generally,
with temps and dewpoints much more reasonable for mid-November by
early Saturday. Precip chances are expected to end by sunset on
Friday, and were eliminated for Friday night.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
As of 430 AM EST Wednesday: Substantial changes are in order for
the forecast into next weekend as the model guidance beyond Friday
has come into better agreement as to the fate of Eta. Thus, expect
a return to autumn. The latest track fcst from NHC keeps the storm
on a northeasterly trajectory moving off the coast of north FL and
GA, to a position well to our southeast by Saturday morning. The
operational model solutions on Saturday are in good agreement that
dry high pressure over the central Appalachians will be firmly in
control of our weather, while a much weaker and slower sfc front
approaches from the west. With Eta no longer a factor by this time,
if all goes according to plan, Saturday looks like a fine autumn
day with plenty of sunshine and dry air. The front may not approach
until late in the day on Sunday. With this trend in the guidance,
some changes are in order, mainly to eliminate the precipitation
chances entirely for Saturday and Saturday night, while lowering
temps a few degrees. The consensus now shows the front reaching
the mtns Sunday night, with a chance of showers, but with precip
not making it over the barrier to any great degree. From Monday
onward, no changes were made as the forecast still looks dry with
a large continental high moving in from the west and reinforcing
our dry and seasonal weather.

&&

.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
At KCLT and elsewhere: Very soupy air mass in place, with
all sites IFR or lower to start the 12z TAFs. A band of heavy
showers has set up along and east of a line from KGSP to KHKY,
and now over KCLT. Areas to the west are seeing lighter showers,
but more fog. This relative lull in shower activity will slowly
shift east, then another round of showers and possibly some
isolated thunderstorms is expected to develop this aftn across
the area. A cold front will push in from the west tonight and
could focus continued convective activity this evening thru the
overnight. Cigs and vsby are expected to improve somewhat late
morning thru the aftn, then deteriorate again this evening. Winds
will be out of the S or SE today, shifting slightly to SW tonight.

Outlook: Warm and moist flow at low-levels off the Atlantic will
continue to produce ceiling restrictions through Thursday night,
with periods of widespread showers. Periods of MVFR to IFR cigs
can be expected until a cold front pushes into the area on Friday.

Confidence Table...

            12-18Z        18-24Z        00-06Z        06-12Z
KCLT       High  80%     High  80%     Med   76%     Med   77%
KGSP       High  80%     High  81%     Med   73%     High  89%
KAVL       Med   70%     Med   75%     Med   74%     High  93%
KHKY       Med   79%     Med   73%     Med   77%     Med   65%
KGMU       Med   76%     Med   74%     Med   74%     High  81%
KAND       Low   55%     High  84%     Med   79%     High  81%

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

www.weather.gov/gsp/aviation

&&

.CLIMATE...
              MAX TEMPERATURE         MIN TEMPERATURE
  STATION      HIGH        LOW         HIGH        LOW
  -------  ----------  ----------  ----------  ----------
   KAVL      75 1949     34 1913     55 2002     18 1973
                                                    1957
   KCLT      78 2006     42 1926     62 1883     24 1973
                1890                                1913
   KGSP      81 1890     41 1968     60 2002     18 1913

RECORDS FOR 11-12

               MAX TEMPERATURE         MIN TEMPERATURE
  STATION      HIGH        LOW         HIGH        LOW
  -------  ----------  ----------  ----------  ----------
   KAVL      77 1890     35 1968     56 1929     16 1894
                            1934
   KCLT      81 1989     43 1894     61 1915     24 1894
   KGSP      81 1989     43 1968     58 1935     19 1913

&&

.GSP WATCHES/WARNINGS/ADVISORIES...
GA...Flood Watch through Thursday evening for GAZ010.
NC...Flood Watch through Thursday evening for NCZ033-035>037-
     048>053-056>059-062>065-068>072-082-501>510.
SC...Flood Watch through Thursday evening for SCZ001>003-005>009.

&&

SYNOPSIS...PM
NEAR TERM...ARK
SHORT TERM...PM
LONG TERM...PM
AVIATION...ARK
CLIMATE...

Hazardous Weather Outlook
National Weather Service Greenville-Spartanburg SC
547 AM EST Wed Nov 11 2020

GAZ010-NCZ033-035>037-048>053-056>059-062>065-068>072-082-501>510-
SCZ001>003-005>009-121100-
Rabun-Avery-Alexander-Iredell-Davie-Madison-Yancey-Mitchell-Swain-
Haywood-Buncombe-Catawba-Rowan-Graham-Northern Jackson-Macon-
Southern Jackson-Transylvania-Henderson-Cleveland-Lincoln-Gaston-
Mecklenburg-Cabarrus-Union NC-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 Pickens-Greater Greenville-Spartanburg-Cherokee-York-
547 AM EST Wed Nov 11 2020

...FLOOD WATCH IN EFFECT THROUGH THURSDAY EVENING...

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.

   Flood Watch.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday.

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

   Flood Watch.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be needed. Please relay any information about
observed severe weather to the NWS while following all local, state,
and CDC guidelines.

GAZ017-018-026-028-029-SCZ004-010>014-019-121100-
Habersham-Stephens-Franklin-Hart-Elbert-Greater Oconee-Anderson-
Abbeville-Laurens-Union SC-Chester-Greenwood-
547 AM EST Wed Nov 11 2020

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

.DAY ONE...Today and tonight.

Widespread showers with embedded isolated to scattered thunderstorms
are expected this morning, followed by another round tonight that
may result in locally heavily rainfall and a few cloud-to-ground
lightning strikes.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday.

Through Thursday, a pool of tropical moisture along a cold front may
support heavy rainfall with isolated flash flooding of low lying
areas including near streams and urban areas.

.SPOTTER INFORMATION STATEMENT...

None.

ARK

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
416 AM EST Wed Nov 11 2020

NCZ033-068-501>510-111015-
Greater Rutherford NC-McDowell Mountains NC-Caldwell Mountains NC-
Burke Mountains NC-Cleveland NC-Greater Burke NC-Greater Caldwell NC-
Polk Mountains NC-Rutherford Mountains NC-Eastern McDowell NC-
Avery NC-Eastern Polk NC-
416 AM EST Wed Nov 11 2020

...OCCASIONAL HEAVY RAIN SHOWERS WILL IMPACT
MCDOWELL...RUTHERFORD...POLK... CALDWELL...SOUTHEASTERN
AVERY...CLEVELAND AND BURKE COUNTIES UNTIL 515 AM EST...

At 414 AM EST, Doppler radar was tracking a heavy rain shower near
Marion, moving north at 35 mph. This shower was part of a large area
of rain with embedded heavier showers streaming northward across the
North Carolina Foothills.

Locations to be impacted include...
Shelby, Lenoir, Morganton, Forest City, Marion, Rutherfordton,
Columbus, Sawmills, Granite Falls and Valdese.

Brief very heavy rainfall rates up to 2 inches per hour 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.

&&

LAT...LON 3612 8155 3610 8152 3610 8150 3607 8144
      3607 8141 3604 8140 3602 8135 3600 8133
      3592 8134 3580 8133 3556 8154 3517 8152
      3520 8229 3552 8221 3553 8217 3555 8220
      3582 8213 3589 8198 3611 8181 3612 8169
TIME...MOT...LOC 0914Z 195DEG 30KT 3570 8197

MOORE

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
538 AM EST Wed Nov 11 2020

NCZ035-056-068>070-502-504-111130-
Gaston NC-Cleveland NC-Lincoln NC-Greater Burke NC-
Greater Caldwell NC-Alexander NC-Catawba NC-
538 AM EST Wed Nov 11 2020

...OCCASIONAL HEAVY RAIN SHOWERS WILL IMPACT
CATAWBA...ALEXANDER...WESTERN LINCOLN...EASTERN
CALDWELL...CLEVELAND...WESTERN GASTON AND SOUTHEASTERN BURKE
COUNTIES UNTIL 630 AM EST...

At 536 AM EST, Doppler radar was tracking a heavy rain shower 4
miles northeast of Shelby, or 4 miles southwest of Waco, moving
north at 35 mph. The shower was part of a large area of rain with
embedded heavier rain showers streaming northward across the North
Carolina Foothills.

Locations to be impacted include...
Hickory, Shelby, Lenoir, Newton, Lincolnton, Taylorsville, Kings
Mountain, St. Stephens, Conover and Cherryville.

Brief very heavy rainfall rates up to 2 inches per hour 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.

&&

LAT...LON 3600 8133 3603 8127 3604 8103 3602 8102
      3516 8132 3518 8177 3535 8170 3559 8170
      3603 8148 3607 8140
TIME...MOT...LOC 1036Z 195DEG 48KT 3531 8147

MOORE