Areal Flood Warning 21, NWS Greenville-Spartanburg, SC

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
159 PM EDT Sun Jun 9 2019

.SYNOPSIS...
A low pressure system west of the region will continue to pump
moisture from the Gulf of Mexico over the southern Appalachians and
surrounding areas through Monday. A cold front will arrive from the
northwest on Monday night, but likely stall over the region on
Tuesday, with abundant moisture returning through Wednesday. Another
cold front will finally push through the region late in the week to
bring in drier air from the west.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 155 pm: Numerous to widespread moderate to heavy rain showers
persist along CAD boundary/convergence axis and within the best low
level Atlantic moisture transport, generally from Charlotte and
vicinity through the northern mtns and foothills. Meanwhile, another
area of showers and embedded thunderstorms will continue lifting
into the Upper Savannah River Valley through the afternoon. PWATs of
around 2 inches and a warm cloud layer of just under 12 kft will
continue to support very efficient rainfall rates of .25 to .5 inch
per hour across these areas, with localized rates up to one
inch/hour. New flash flooding is already occurring across portions
of the northern foothills, and additional flooding may also develop,
especially across the northern foothills, where rainfall amounts of
around an inch in an hour, or a couple of inches over 3 to 6 hours
should be enough to produce additional problems.

A trend toward categorical pops is warranted across much of the
forecast area by late afternoon.  The silver lining is that the
widespread cloud cover and morning shower activity has resulted in
sbCAPE maxing out at around 1000 J/kg across the SC and GA Piedmont,
with instability dropping off considerably to the north and east.
Therefore, we do not expect to see the kind of "scary" rates that
were observed across portions of the Upstate and NC foothills late
yesterday afternoon and evening. Nevertheless, with antecedent
conditions ranging from "wet" to "can't take anymore," localized
flash flooding will remain a concern, even outside of the ongoing
problem areas, especially in urban and other flood-prone locations.

The low-level flow will continue to veer around toward southerly
tonight, which should help relax the upslope component a bit, but
profiles will remain very moist. Although flash flooding will remain
a concern, extensions to the Watch will likely be postponed until
later today.

&&

.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
As of 100 PM EDT Sunday: The upper level trof axis finally crosses
the FA late Mon and a return to a drier pattern ensues thru most of
the short range period. A flat h5 ridge will push in from the west
while stg sfc hipres builds across the lower OH valley. This high
will will begin wedging in from the NE Tue and lower sfc td/s back
into the lower to mid 50s. Some lingering isol showers are possible
across NC mtns and the far srn zones thru mid day...however
additional rainfall amts will be light as profiles continue to dry
out thru a deep layer.

On Wed...a return of s/ly flow abv h925 will occur as a nrn GOM
low develops in response to a deepening Midwestern h5 trof. This low
will push ne during the day and bring a good amt of sfc-h7 moisture
to interact with the existing sfc wedge. Soundings show a definitive
capping inversion arnd 10kft...so showers that do develop will be
remain shallow and produce low-end amts of precip thru the end of
the period. The atmos will remain rather stable thru the period with
the deeper instability shunted east and south of the area...however
better h5 forcing moves in late Wed and a few general tstms are
possible across the wrn mtns. High temps on Tue will remain a little
below normal and with relatively low td/s...a rather pleasant day
will be in store. Increasing clouds and precip will reinforce the
sfc wedge and ne/ly sfc flow will combine to lower max temps arnd
10-12 degrees below seasonal levels.

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
As of 140 PM EDT Sunday: Starting 00Z Thursday...with the 500mb
pattern showing a trough with axis over the Mississippi River and a
ridge over the West Coast States. Energy rounding the base of the
trough will combine with low pressure from northern Florida tracking
NE to be crossing Virginia Thursday morning. The previous run of the
GFS had at least a 1000 CAPE over most of the Carolina piedmont
Thursday afternoon. The newest GFS run has 500 to 600 CAPE and east
of I-77 with more dry air moving in from the west.  This agrees with
the ECMWF in bringing the dry air in from the west and lowering the
POP. Therefore, only isolated to widely scattered convection
Thursday for the western Carolinas then clearing out Thursday night.

High pressure will transition from west to east across the SE States
Friday and Saturday.  The EC keeps the Carolinas and GA nearly cloud
free into early Sunday while the GFS brings more clouds in Saturday
night ahead of the next front moving SE from KY and TN.  The GFS
brings rain into our area Sunday afternoon while the EC holds off
until at least late Monday.

Temperatures will be 5 to 7 degrees below normal Thursday getting a
little warmer into the weekend getting near normal by Sunday.

&&

.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
At KCLT and elsewhere: Showers, along with a few thunderstorms will
increase in coverage across the Terminal Forecast Area through the
afternoon. Cigs will lift to or remain MVFR through much of the
afternoon, while periods of MVFR/IFR visby will be possible during
times of heavier rain. Convection should gradually wind down from
mid-evening into the early part of the overnight, with the TAF
mention tapering down to a VCSH at all sites after midnight.
Otherwise, cigs will return to IFR/LIFR overnight.

Outlook: Widespread showers and thunderstorms, some with very heavy
rainfall, and associated restrictions may redevelop as a cold front
crosses the area Monday. Some improvement is possible Tuesday
through Wednesday in the wake of the front.

Confidence Table...

            18-24Z        00-06Z        06-12Z        12-18Z
KCLT       High  81%     High  88%     Med   72%     Med   74%
KGSP       Med   63%     Low   59%     Med   67%     High  80%
KAVL       High  87%     Med   73%     High  88%     High  86%
KHKY       Med   74%     Med   68%     High  85%     High  81%
KGMU       Med   66%     Med   72%     Med   73%     High  84%
KAND       Med   71%     Med   62%     Med   67%     Med   77%

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

&&

.HYDROLOGY...
Updated Flash Flood Guidance values for 6-hour periods are generally
running 1 to 2 inches in wet western NC locations, and around 3
inches elsewhere. These rates remain attainable given the rainfall
efficiency observed thus far and indicated in profiles going forward
given the deep (12+ kft) warm cloud layers. The WPC Moderate risk of
Excessive Rainfall looks well placed today.

Flooding in urban areas may continue to develop very quickly as
local drainage systems get overwhelmed by the rainfall rates, and
high stream and river levels now occurring in the NC foothills have
that area particularly primed for additional flooding.

&&

.GSP WATCHES/WARNINGS/ADVISORIES...
GA...Flash Flood Watch until 8 PM EDT this evening for GAZ010-017-
     018-026-028-029.
NC...Flash Flood Watch until 8 PM EDT this evening for NCZ033-
     035>037-049-050-053-056-057-059-062>065-068>072-082-
     501>510.
SC...Flash Flood Watch until 8 PM EDT this evening for SCZ001>014-
     019.

&&

SYNOPSIS...DEO
NEAR TERM...HG/JDL
SHORT TERM...SGL
LONG TERM...SGL
AVIATION...JDL
HYDROLOGY...

Hazardous Weather Outlook
National Weather Service Greenville-Spartanburg SC
511 AM EDT Sun Jun 9 2019

GAZ010-017-018-026-028-029-NCZ033-035>037-049-050-053-056-057-059-
062>065-068>072-082-501>510-SCZ001>014-019-100915-
Rabun-Habersham-Stephens-Franklin-Hart-Elbert-Avery-Alexander-
Iredell-Davie-Yancey-Mitchell-Buncombe-Catawba-Rowan-
Northern Jackson-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-
511 AM EDT Sun Jun 9 2019

...FLASH FLOOD WATCH IN EFFECT THROUGH THIS 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.

   Flash Flood Watch.

.DAYS TWO THROUGH SEVEN...Monday through Saturday.

An unsettled weather pattern will continue through mid-week.
Additional heavy rainfall and flooding will be possible each day.

.SPOTTER INFORMATION STATEMENT...

None.

NCZ048-051-052-058-100915-
Madison-Swain-Haywood-Graham-
511 AM EDT Sun Jun 9 2019

This Hazardous Weather Outlook is for western North Carolina.

.DAY ONE...Today and tonight.

Heavy rainfall and flooding will be possible today and tonight.

.DAYS TWO THROUGH SEVEN...Monday through Saturday.

An unsettled weather pattern will continue through mid-week.
Additional heavy rainfall and flooding will be possible each day.

.SPOTTER INFORMATION STATEMENT...

Spotters are requested to forward any reports of large hail,
damaging winds, tornadoes, or flash flooding to our office.