Tornado Warning 10, NWS Greenville-Spartanburg, SC

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
655 AM EDT Thu Sep 26 2024

.SYNOPSIS...
Tropical Cyclone Helene is forecast to make landfall over the
Florida Panhandle late today. The remnant circulation will move
quickly north through Georgia bringing continued heavy rainfall,
significant flooding and strong winds tonight into Friday morning.
Expect a calmer weekend with temperatures near seasonal normals.

&&

.NEAR TERM /THROUGH FRIDAY/...
As of 3:45 am Thursday: ***A MAJOR RAINFALL EVENT FOR THE SOUTHERN
APPALACHIANS AND VICINITY WITH THE POTENTIAL FOR WIDESPREAD TO
CATASTROPHIC FLASH FLOODING IS OCCURRING***

A wide band of moderate to heavy showers continues to stream north-
ward within a plume of deep tropical moisture to the east of a
stalled frontal bndy still over eastern TN. Thus, the Predecessor
Rain Event (PRE) continues with a handful of Flash Flood Warnings
having been issued since midnight. We have not seen much if any
lightning over our area over the past few hrs, but the I-77 corridor
still appears to have upwards of 500 J/kg of sfc-based CAPE and deep
layer shear of 30 to 40 kt. Thus, another brief tornado remains
possible going forward. Nonetheless, the flash flood threat contin-
ues to increase as the rain continues to fall, mainly over the
foothills and along/near the Blue Ridge Escarpment. Another broad
area of heavier rain is currently approaching our area from the
south within this moist conveyor belt. This rain will likely put
more streams into flood thru the early morning hrs.

Otherwise, no changes were made to the Tropical Storm Warning or
the Flood Watch with this fcst update. The latest CAMs are still
suggesting that a swath of stronger wind gusts will spread over
our area just after 00z Friday and continue thru the morning. They
should start weakening by the afternoon, but conditions will remain
gusty thru the evening. Otherwise, all signs point to a significant
tropical event across the western Carolinas and northeast Georgia.
Helene will be a large and fast-moving storm, so any additional
minor shifts in the storm track probably won't change much at this
point. We still expect a rare and significant amount of rainfall
over much of our mountains and adjacent zones with damaging to
catastrophic flooding likely. In the past, once the rainfall gets
above roughly ten inches, we have seen numerous reports of land-
slides across the high terrain. If you live in these areas, it is
imperative that you take whatever precautions you can now, as the
flood/landslide threat will continue to increase today and tonight.

&&

.SHORT TERM /FRIDAY NIGHT THROUGH SATURDAY NIGHT/...
As of 245 am EDT Wednesday: Calm weather will return to the CWA by
Friday night, as the center of Helen will be spinning down over the
western Ohio Valley...with only some spotty showers expected to
linger across the mountains. Winds will remain gusty Fri evening...
albeit well below any Wind Advisory criteria...but will gradually
diminish through the night. With upper low remaining virtually
stationary across the TN/OH Valley, spokes of vorticity lifting
south of the low will approach the southern Appalachians Saturday
into Saturday night. This is expected to induce scattered shower
development...with perhaps a thunderstorm or two...mainly Saturday
afternoon/evening. Can't rule out some locally heavy rainfall within
any of this activity, but any precipitation should mostly be light.
Temperatures will be right around normal through the period.

&&

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
As of 200 am EDT Thursday: Global model guidance is not in the
greatest agreement regarding the details of the evolution in the
upper pattern. However, as a strong short wave trough dips into the
northern Great Plains, the general idea is that the upper low...
centered somewhere over the Ohio Valley at the start of the
extended...will begin to wobble across the Mid-Atlantic and evolve
into an open wave at some point early next week. Scattered, mainly
diurnal convection (primarily showers) will be possible across the
forecast area each day from Sunday through Tuesday...with chances
becoming increasingly confined to the mountains later in the period,
as the pattern transitions to more of a NW flow regime in the wake
of the departing trough. Although precip chances are in the
forecast for much of the period, any rainfall is expected to be
light. Temperatures are forecast to be very close to climo through
the period.

&&

.AVIATION /12Z THURSDAY THROUGH MONDAY/...
At KCLT and elsewhere: Moderate to heavy showers now cover most
of the fcst area with most terminals reporting either MVFR or IFR
cigs and visby at this time. Unfortunately, the worst is yet to
come. We could see a few lightning strikes embedded in the heavier
showers thru the morning with cigs dropping to IFR across the area
as more upslope forcing arrives and the deeper tropical moisture
streams up from the south. Once there, terminals should stay down
in the LIFR/IFR range for the rest of the taf period. Expect fre-
quent heavier showers to move thru the area with winds becoming
gusty from the SE after daybreak. Winds and gusts will continue
to strengthen later tonight and into Friday.

Outlook: TC Helene will bring widespread low cigs, heavy rain,
strong winds, and low-lvl wind shear thru Friday morning before
moving out of the area late Friday into Saturday. Isolated to
sct mainly diurnal convection will be possible thru the weekend.

&&

.GSP WATCHES/WARNINGS/ADVISORIES...
GA...Flood Watch through Friday afternoon for GAZ010-017-018-026-
     028-029.
     Tropical Storm Warning for GAZ010-017-018-026-028-029.
NC...Flood Watch through Friday afternoon for NCZ033-035-048>053-
     056-058-059-062>065-068-069-501>510.
     Tropical Storm Warning for NCZ033-048>053-056-058-059-062>065-
     068>071-082-501>510.
SC...Flood Watch through Friday afternoon for SCZ008-010>013-019-
     101>109.
     Tropical Storm Warning for SCZ008>014-019-101>109.
&&

SYNOPSIS...JDL
NEAR TERM...JPT
SHORT TERM...JDL
LONG TERM...JDL
AVIATION...JPT

Hazardous Weather Outlook
National Weather Service Greenville-Spartanburg SC
610 PM EDT Wed Sep 25 2024

GAZ010-017-018-026-028-029-NCZ033-048>053-056-058-059-062>065-068-
069-501>510-SCZ008-010>013-019-101>109-262215-
Rabun-Habersham-Stephens-Franklin-Hart-Elbert-Avery-Madison-Yancey-
Mitchell-Swain-Haywood-Buncombe-Catawba-Graham-Northern Jackson-
Macon-Southern Jackson-Transylvania-Henderson-Cleveland-Lincoln-
Caldwell Mountains-Greater Caldwell-Burke Mountains-Greater Burke-
McDowell Mountains-Eastern McDowell-Rutherford Mountains-
Greater Rutherford-Polk Mountains-Eastern Polk-Cherokee-Anderson-
Abbeville-Laurens-Union SC-Greenwood-Oconee Mountains-
Pickens Mountains-Greenville Mountains-Greater Oconee-
Greater Pickens-Central Greenville-Southern Greenville-
Northern Spartanburg-Southern Spartanburg-
610 PM EDT Wed Sep 25 2024

...FLOOD WATCH IN EFFECT THROUGH FRIDAY AFTERNOON...
...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...Tonight.

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

   Flood Watch.
   Tropical Storm Warning.

.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.
   Tropical Storm Warning.

A tropical system is expected to strengthen over the Gulf of Mexico
on Thursday as it tracks northward. This system will impact the
western Carolinas and northeast Georgia Thursday and Friday,
bringing gusty winds, heavy rainfall, and flooding to the area.

.SPOTTER INFORMATION STATEMENT...

None.

NCZ070-071-082-SCZ009-014-262215-
Gaston-Mecklenburg-Union NC-York-Chester-
610 PM EDT Wed Sep 25 2024

...TROPICAL STORM WARNING IN EFFECT...

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

.DAY ONE...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.

.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.

   Tropical Storm Warning.

A tropical system is expected to strengthen over the Gulf of Mexico
on Thursday as it tracks northward. This system will impact the
western Carolinas and northeast Georgia Thursday and Friday,
bringing gusty winds, heavy rainfall, and flooding to the area.

.SPOTTER INFORMATION STATEMENT...

None.

NCZ036-037-057-072-262215-
Iredell-Davie-Rowan-Cabarrus-
610 PM EDT Wed Sep 25 2024

This Hazardous Weather Outlook is for the northwest Piedmont of North
Carolina.

.DAY ONE...Tonight.

Another round of scattered thunderstorms is expected this evening and
into the overnight hours. Some of these storms could become strong
to severe and produce damaging wind gusts and hail. Heavy rainfall
can occur with any storm.

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

A tropical system is expected to strengthen over the Gulf of Mexico
on Thursday as it tracks northward. This system will impact the
western Carolinas and northeast Georgia Thursday and Friday,
bringing gusty winds, heavy rainfall, and flooding to the area.

.SPOTTER INFORMATION STATEMENT...

None.

NCZ035-262215-
Alexander-
610 PM EDT Wed Sep 25 2024

...FLOOD WATCH IN EFFECT THROUGH FRIDAY AFTERNOON...

This Hazardous Weather Outlook is for piedmont North Carolina.

.DAY ONE...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.

A tropical system is expected to strengthen over the Gulf of Mexico
on Thursday as it tracks northward. This system will impact the
western Carolinas and northeast Georgia Thursday and Friday,
bringing gusty winds, heavy rainfall, and flooding to the area.

.SPOTTER INFORMATION STATEMENT...

None.

PM

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
839 AM EDT Thu Sep 26 2024

SCZ009-261315-
York SC-
839 AM EDT Thu Sep 26 2024

...GUSTY SHOWERS WILL IMPACT SOUTHEASTERN YORK COUNTY THROUGH 915 AM
EDT...

At 838 AM EDT, Doppler radar was tracking gusty showers 5 miles
southeast of Rock Hill, or over Lesslie, moving north at 25 mph.

HAZARD...Wind gusts up to 40 mph.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects.

Locations impacted include...
Rock Hill, Fort Mill, Tega Cay, Lesslie, Catawba, Carowinds, and Lake
Wylie.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

Conditions are favorable for development of a very brief, weak
tornado. Be prepared to take immediate action if a tornado is sighted
or a Tornado Warning is issued.

&&

LAT...LON 3490 8088 3487 8088 3484 8087 3482 8090
      3482 8104 3503 8107 3510 8094 3506 8090
      3503 8090 3501 8091 3499 8089 3497 8088
      3496 8087 3492 8086
TIME...MOT...LOC 1238Z 178DEG 23KT 3489 8094

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...40 MPH

8

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
912 AM EDT Thu Sep 26 2024

NCZ056-261345-
Catawba NC-
912 AM EDT Thu Sep 26 2024

...GUSTY SHOWERS WILL IMPACT SOUTHEASTERN CATAWBA COUNTY THROUGH 945
AM EDT...

At 911 AM EDT, Doppler radar was tracking gusty showers 7 miles
southeast of Newton, or 4 miles east of Maiden, moving north at 15
mph.

HAZARD...Wind gusts up to 40 mph.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects.

Locations impacted include...
Newton, Conover, Maiden, Claremont, Catawba, St. Stephens, Bandys,
and Sherrills Ford.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

Conditions are favorable for development of a very brief, weak
tornado. Be prepared to take immediate action if a tornado is sighted
or a Tornado Warning is issued.

&&

LAT...LON 3571 8106 3571 8101 3555 8102 3556 8121
      3573 8129 3574 8107
TIME...MOT...LOC 1311Z 173DEG 14KT 3559 8112

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...40 MPH

8