Flash Flood Warning 62, NWS Greenville-Spartanburg, SC

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
757 AM EDT Thu Oct 29 2020

.SYNOPSIS...
Periods of moderate to heavy rainfall and gusty southerly winds
will continue through this morning as Tropical Storm Zeta moves
through the area. Conditions rapidly improve this afternoon as Zeta
departs with cool and dry weather prevailing in its wake through
early next week.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 645 AM EDT Thursday: A Tropical Storm Watch, Flash Flood
Watch, and Wind Advisory remain in effect across portions of the
area.

Minor adjustments made to temps/PoPs to coincide with latest trends
as the rest of the near term forecast remains on track. Zeta
continues to rapidly move with a forward motion of 39 mph as
satellite imagery depicts the system nearly over the Carolinas
already. Precip continues to move in across the area with minor
flooding concerns developing as noted by a few flood advisories now
in effect. In addition to rainfall, low stratus and patchy areas of
fog prevail across the area this morning with current temps in the
upper 60s to lower 70s.

Previous discussion: With plenty of moisture in place, upslope flow,
and Zeta moving closer, expect showers shift eastward through the
morning hours. Could not entirely rule out an isolated brief tornado
this morning. Otherwise, anticipate increasing chances for
thunderstorms across the southeastern portions of the FA later this
morning into early this afternoon with increasing instability. As
for winds, expect winds and wind gusts (up to 40 to 50 kts possible)
to increase this morning as the pressure gradient tightens and the
center of TS Zeta moves overhead. With saturated soils and expected
winds, downed trees and powerlines could become an issue today. With
a very warm and moist airmass in place as the FA sits well in the
warm sector, expect max temps to climb into the upper 70s/near 80
degrees.

Latest guidance continues to prog that Zeta will be a distant memory
for the Carolinas this afternoon as the remnants lift off to the
northeast, while upstream, southern stream upper troughing moves
into the TN Valley and a cold front approaches the area. Could not
rule out lingering showers on the back of Zeta across the area,
especially the mountains in NW flow, but overall expect the
widespread nature of the activity to dissipate later this afternoon.
Higher winds will subside as the gradient begins to relax, but
lingering low end gusts will persist into tonight. Min temps will
remain just above normal.

&&

.SHORT TERM /FRIDAY THROUGH SUNDAY NIGHT/...
As of 300 am Thursday: Cooler and much drier air will be advecting
into the forecast area at the start of the period in the wake of
departing frontal system. Gusty northwest winds acting on lingering
low level moisture from the TN Valley into the crest of the
Appalachians could result in development of a few showers along the
TN border mainly Fri morning, warranting a small pop in those areas.
Otherwise, the big story for the short term will be the potential
for frost/freeze conditions Fri night/Sat morning, mainly across the
mountains and northern Piedmont zones. Current indications are that
widespread frost, and at least locally freezing temperatures can be
expected across the mtns Sat morning, with at least patchy frost in
the Piedmont/foothills north of I-85. As such, a Freeze Watch may
need to be entertained for portions of the mountains this afternoon.
Despite strong insolation Saturday, max temps are expected to
average around 10 degrees below climo.

Otherwise, temps will moderate briefly late in the period...albeit
remaining a bit below climo, as heights rise downstream of the next
round of central Conus height falls. Frontal zone associated with
these height falls is expected to approach the forecast area quickly
late Sat night/early Sunday. A consensus of the latest deterministic
model guidance suggests moisture return will be sufficient to maybe
ring our some -RA over the area Sunday morning, and a small pops has
been introduced to account for this.

&&

.LONG TERM /MONDAY THROUGH WEDNESDAY/...
As of 330 AM Wednesday: Cold frontal passage will be complete
by the early overnight hours Monday morning over the eastern
counties and CAA will be well underway.  Winds may be brisk over
the mountains early Monday morning as a tight pressure gradient
develops between the 1037mb high over the central Plains and the
surface trough offshore.  CAA will supplant traditional radiational
cooling and, given the slightly warmer temperatures for Saturday
morning, result in the first widespread freeze of the season for the
mountains, including over extreme northeast Georgia.  These winds
should work to limit widespread frost development Monday morning,
but temps are still expected to bottom out in the mid-30s across
the North Carolina Piedmont and upper 30s across the Upstate,
or about 6-8 degrees below normal regionwide.

Despite clear skies, anomalously low thicknesses associated with
the potent longwave trough responsible for the cold front (guidance
shows the 540dm isopleth dipping as far south as northern Virginia)
will support the ongoing CAA to produce the coldest highs of the
season thus far.  Temperatures will struggle to reach 40 across the
higher elevations (the very highest peaks may not break freezing),
with most of the NC Piedmont and the northern Upstate struggling
to reach 55.  These temperatures are 12-15 degrees below normal
or equivalent to normal highs in mid-December.  Fortunately these
low maxes are still 6-10 degrees above record values.

Winds will weaken considerably by Monday night and radiational
cooling should dominate the area Tuesday morning as 1030mb high
pressure settles into the Deep South.  These conditions should
support slightly colder temps compared to Monday in the mountains
for a deeper freeze and perhaps the first light freeze of the
season for nearly all of the North Carolina Piedmont and Foothills
as well as portions of the Upstate, as temps dip into the lower 30s.

As we head towards the middle of the work week we are going to
see a nice recovery take shape as strong high pressure slides
offshore in response to height rises over the eastern CONUS.
Subtropical ridging once again returns to the Deep South which
will support continued dry but milder conditions Tuesday through
the end of the work week.  Expect non-mountain highs to rebound to
around 60 for Tuesday and return to near-normal values by Wednesday.
Frost concerns should be minimal by Thursday morning.

&&

.AVIATION /12Z THURSDAY THROUGH MONDAY/...
At KCLT and elsewhere: Below normal confidence in 12Z TAFs through
16Z with improving confidence after that. Wind gusts may be +/-
10 kts from TAF at times through 18Z. There is about a 10
percent chance of TSRA through 16Z except lingering through 00Z
for I-77 corridor including KCLT. A cold front pushing through
the region will likely sustain low end W/NW gusts for many
terminals through the end of the TAF period.

Outlook: Expect VFR except IFR/MVFR possibly lingering across the
mountains, especially near TN border through early Saturday.

Confidence Table...

            12-18Z        18-24Z        00-06Z        06-12Z
KCLT       High  89%     High  94%     High  98%     High 100%
KGSP       High  81%     High  97%     High  98%     High 100%
KAVL       High  83%     High  96%     High 100%     High  84%
KHKY       High  85%     High  97%     High 100%     High 100%
KGMU       High  83%     High  96%     High  99%     High 100%
KAND       High  90%     High  90%     High  97%     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 are available at
the following link:

www.weather.gov/gsp/aviation

&&

.GSP WATCHES/WARNINGS/ADVISORIES...
GA...Flash Flood Watch until 2 PM EDT this afternoon for GAZ010-017-
     018.
     Tropical Storm Warning for GAZ010-017-018-026-028.
     Wind Advisory until 6 PM EDT this evening for GAZ029.
NC...Flash Flood Watch until 2 PM EDT this afternoon for NCZ033-
     048>053-058-059-062>065-501>507-509.
     Tropical Storm Warning for NCZ033-035>037-048>053-056>059-
     062>065-068>072-501>510.
     Wind Advisory until 6 PM EDT this evening for NCZ082.
SC...Flash Flood Watch until 2 PM EDT this afternoon for SCZ001>003.
     Tropical Storm Warning for SCZ001>010.
     Wind Advisory until 6 PM EDT this evening for SCZ011>014-019.

&&

SYNOPSIS...Munroe
NEAR TERM...SGL
SHORT TERM...JDL
LONG TERM...JMP
AVIATION...Munroe

Hazardous Weather Outlook
National Weather Service Greenville-Spartanburg SC
520 AM EDT Thu Oct 29 2020

GAZ026-028-NCZ035>037-056-057-068>072-508-510-SCZ004>010-300930-
Franklin-Hart-Alexander-Iredell-Davie-Catawba-Rowan-Cleveland-
Lincoln-Gaston-Mecklenburg-Cabarrus-Greater Rutherford-Eastern Polk-
Greater Oconee-Greater Pickens-Greater Greenville-Spartanburg-
Cherokee-York-Anderson-
520 AM EDT Thu Oct 29 2020

...TROPICAL STORM WARNING IN EFFECT...

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.

   Tropical Storm Warning.

A threat for localized flash flooding will exist for much of the
area through today as the remnants of tropical cyclone Zeta rapidly
move across the Southeast. There is also a small threat of isolated
tornadoes across Piedmont. Monitor the latest forecast for updates
on this system.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday.

Hazardous weather is not expected at this time.

.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.

GAZ010-017-018-NCZ033-048>053-058-059-062>065-501>507-509-SCZ001>003-
300930-
Rabun-Habersham-Stephens-Avery-Madison-Yancey-Mitchell-Swain-Haywood-
Buncombe-Graham-Northern Jackson-Macon-Southern Jackson-Transylvania-
Henderson-Caldwell Mountains-Greater Caldwell-Burke Mountains-
Greater Burke-McDowell Mountains-Eastern McDowell-
Rutherford Mountains-Polk Mountains-Oconee Mountains-
Pickens Mountains-Greenville Mountains-
520 AM EDT Thu Oct 29 2020

...FLASH FLOOD WATCH IN EFFECT UNTIL 2 PM EDT THIS AFTERNOON...
...TROPICAL STORM WARNING IN EFFECT...

This Hazardous Weather Outlook is for northeast Georgia, 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.
   Tropical Storm Warning.

There is a small threat of isolated tornadoes across foothill areas
as the remnants of Zeta move through during the day. Monitor the
latest forecast for updates on this system.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday.

Hazardous weather is not expected at this time.

.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.

GAZ029-NCZ082-SCZ011>014-019-300930-
Elbert-Union NC-Abbeville-Laurens-Union SC-Chester-Greenwood-
520 AM EDT Thu Oct 29 2020

...WIND ADVISORY IN EFFECT UNTIL 6 PM EDT THIS EVENING...

This Hazardous Weather Outlook is for northeast Georgia, piedmont
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.

   Wind Advisory.

A threat for localized flash flooding will exist for much of the
area through today as the remnants of tropical cyclone Zeta rapidly
move across the Southeast. There is also a small threat of isolated
tornadoes. Monitor the latest forecast for updates on this system.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday.

Hazardous weather is not expected at this time.

.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.

12

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
807 AM EDT THU OCT 29 2020

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

0617 AM     TROPICAL STORM   4 ESE TOWNVILLE         34.53N 82.83W
10/29/2020                   ANDERSON           SC   LAW ENFORCEMENT

            LAW ENFORCEMENT REPORTED TREE IN ROADWAY ON STELLING DR

&&

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
815 AM EDT THU OCT 29 2020

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

0630 AM     TROPICAL STORM   2 NW CLEMSON            34.71N 82.83W
10/29/2020                   PICKENS            SC   LAW ENFORCEMENT

            LAW ENFORCEMENT REPORTED TREE IN ROADWAY ON
            INTERSECTION OF SC-183 & SC-133

&&

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
816 AM EDT THU OCT 29 2020

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

0640 AM     TROPICAL STORM   6 NNE GREER             35.02N 82.20W
10/29/2020                   SPARTANBURG        SC   LAW ENFORCEMENT

            LAW ENFORCEMENT REPORTED TREE IN ROADWAY ON DEYOUNG &
            SLOAN RD

&&

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
818 AM EDT THU OCT 29 2020

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

0720 AM     TROPICAL STORM   4 WSW ANDERSON          34.50N 82.71W
10/29/2020                   ANDERSON           SC   ASOS

            KAND PEAK GUST 51 KTS.

&&

ARK

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
819 AM EDT THU OCT 29 2020

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

0718 AM     TROPICAL STORM   3 WSW TRAVELERS REST    34.95N 82.49W
10/29/2020                   GREENVILLE         SC   LAW ENFORCEMENT

            LAW ENFORCEMENT REPORTED TREE IN ROADWAY ON KEELER MILL
            RD

&&

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
821 AM EDT THU OCT 29 2020

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

0802 AM     TROPICAL STORM   4 SW SALEM              34.84N 83.02W
10/29/2020                   OCONEE             SC   LAW ENFORCEMENT

            LAW ENFORCEMENT REPORTED TREE IN ROADWAY ON BETHEL
            CHURCH RD

&&