Alert archive / Georgia / Flash Flood Warnings in 2018

Flash Flood Warning 36, NWS Greenville-Spartanburg, SC

May 30, 2018Rabun County, Georgia

NWS Greenville-Spartanburg, SC issued this flash flood warning at May 30, 2018, 6:54 AM EDT for Rabun County, Georgia. It was in force for 5 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
May 30, 2018, 6:54 AM EDT (10:54 UTC)
Expired
May 30, 2018, 12:15 PM EDT
In force
5 hr
Issued by
NWS Greenville-Spartanburg, SC
Area
Storm-based polygon
Flood severity
None

County Rabun County, GA

The radar

The Greer radar (KGSP), 107 km from the middle of the area, began a volume at 10:55 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

Did it verify

Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this flash flood warning while it was in force. That is not proof nothing happened: reports are thin where few people live.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The nearest sounding before it

Peachtre/Fal Fld, GA (KFFC), launched 00:00Z, 10.9 hours before the alert went out and 196 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Peachtre/Fal Fld, GA at 00:00Z on 2018-05-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 235 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Peachtre/Fal Fld, GA at 00:00Z on 2018-05-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 73 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
235 J/kg
Mixed-layer CIN
-43 J/kg
Mixed-layer LCL
867 m above ground
0-6 km bulk shear
23 kt
0-1 km storm-relative helicity
73 m²/s²
0-3 km storm-relative helicity
84 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.4

Open this sounding in Storm Lab

The text

As transmitted.

045 
WGUS52 KGSP 301054
FFWGSP
GAC241-301645-
/O.NEW.KGSP.FF.W.0036.180530T1054Z-180530T1645Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Greenville-Spartanburg SC
654 AM EDT WED MAY 30 2018

The National Weather Service in Greenville-Spartanburg has issued a

* Flash Flood Warning for...
  Rabun County in northeastern Georgia...

* Until 1245 PM EDT Wednesday.

* At 645 AM EDT, high water on the Tallulah River due to heavy 
  rainfall of 2-4 inches over the past 24 hours inches has prompted 
  Georgia Power to release extra water from Lake Burton Dam, Lake 
  Rabun/Mathis Dam, Tallulah Falls Lake and Dam and Lake Tugalo 
  Dam. These releases, combined with the preexisting high water 
  especially on Tiger Creek, is causing rapid rises downstream 
  of Mathis Dam.  Floodwaters have closed Shady Lane 
  and closures may be required shortly along Joy Bridge Road.

* Elsewhere across the county, minor flooding of several 
  secondary roads is ongoing, necessitating notification as people
  begin their morning commutes.  Please avoid all flooded
  roadways and Turn Around, Don't Drown.

* Some locations that will experience flooding include...
  Clayton, Mountain City, Tiger, Dillard, Sky Valley, Lake Rabun,
  Lake Burton, Moccasin Creek State Park, Lakemont and Tallulah Gorge
  State Park.  Shady Lane, Joy Bridge Road, Mathis Dam Road, and 
  Old 441 may all be impacted and portions of these roads may be 
  flooded. Campgrounds and other low-lying areas along the Tallulah 
  River between Lake Burton and the Tallulah Gorge may experience
  rapid rises and flash flooding.

* The excessive rainfall over the warned area has caused numerous
  mud slides and additional mud slides are possible near steep 
  terrain. The mud slide can consist of rock, mud, vegetation and
  other loose materials and are very powerful.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

In hilly and mountainous terrain, there are hundreds of low-water
crossings which can be dangerous in heavy rain. Low-water crossings
can be submerged by flood waters quickly and without warning. Never
attempt to travel across flooded crossings. Find an alternate route.
It takes only a few inches of swiftly flowing water to carry vehicles
away.

Please pay close attention to road signs indicating a flood-prone
area. Obey all barricades, even if water is not currently over the 
road. Barricades are in place for your protection and indicate areas 
where flooding can occur rapidly and without warning.

When it is safe to do so, please report flood waters or landslides
flowing over roads or threatening property to the National Weather
Service by calling toll free, 1, 800, 2 6 7, 8 1 0 1, by posting on
our Facebook page, or via Twitter using hashtag NWSGSP. Your message
should describe the event and the specific location where it
occurred, including roadways, nearby cross streets, stream names and
other landmarks.

&&

LAT...LON 3488 8366 3492 8360 3494 8360 3495 8355
      3499 8355 3500 8310 3499 8310 3495 8313
      3494 8311 3493 8316 3488 8321 3488 8324
      3482 8327 3482 8331 3472 8335 3475 8343
      3473 8351 3475 8355 3482 8359 3483 8366

$$

JMP
1 follow-up statement
660 
WGUS72 KGSP 301615
FFSGSP

Flash Flood Statement
National Weather Service Greenville-Spartanburg SC
1215 PM EDT WED MAY 30 2018

GAC241-301624-
/O.CAN.KGSP.FF.W.0036.000000T0000Z-180530T1645Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Rabun GA-
1215 PM EDT WED MAY 30 2018

...THE FLASH FLOOD WARNING FOR RABUN COUNTY IS CANCELLED...

While heavy rain has ended, flooding continues over the warned area 
and the Flash Flood Warning has been replaced by a Flood 
Warning.

LAT...LON 3488 8366 3492 8360 3494 8360 3495 8355
      3499 8355 3500 8310 3499 8310 3495 8313
      3494 8311 3493 8316 3488 8321 3488 8324
      3482 8327 3482 8331 3472 8335 3475 8343
      3473 8351 3475 8355 3482 8359 3483 8366

$$

WJM

What forecasters said that day

The local office's own words before this flash flood warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Greenville-Spartanburg, SC wrote its last area forecast discussion before this flash flood warning went out at May 30, 3:42 AM EDT, 3 hours 12 minutes earlier.

Area forecast discussion, May 30, 3:42 AM EDT, 3 hours 12 minutes before
Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
342 AM EDT Wed May 30 2018

.SYNOPSIS...
Deep tropical moisture will persist over the area today as the
remnants of Alberto move northward toward the Great Lakes. A moist
airmass will then persist on Thursday into Friday, with a few waves
of thunderstorms arriving from the west. Slightly drier air will mix
in from the west over the weekend, but moisture may return by late
weekend or early next week.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 330 AM EDT Wednesday: Though portions of the Flash Flood
Watch will expire at 8 AM this morning, areas across the
mountains and NC foothills will remain under a watch through
Thursday morning.

Showers continue to move northward across the FA this morning
(mainly west of the I-77 corridor) as seen from latest radar
imagery, with redevelopment especially continuing across the
upslope areas. Per latest guidance, the remnant circulation of
Alberto, currently over western TN, will move up into the upper
midwest today and become absorbed into the upper shortwave
trough as an upper ridge remains in place along the eastern
seaboard. This along with the Atlantic high in place will keep
the continued infiltration of moisture from the GOM into the
Southeast. As flow becomes more southwesterly today, anticipate
most of the showers and isolated thunderstorms to remain
concentrated across the mountains, as is noted with latest CAMs.
With this expected trend and given the recent rainfall and
ongoing flooding situations this morning, the Flash Flood Watch
for the mountains and portions of the NC foothills will remain
in effect through Thursday morning. Flooding and mountain
landslides will remain a primary concern. Given very saturated
soils, it won't take much for a few trees to topple over as well,
even with a minimal wind gusts. Elsewhere across the Upstate
and NW Piedmont, with a few breaks in the clouds and daytime
heating, isolated to scattered showers and thunderstorms will be
possible as well today and tonight.

Into this evening, in the wake of Alberto, another shortwave trough
will near the Carolinas from the west tonight and will keep the
unsettled weather pattern in place. Temperatures today and
tonight will remain just below normal.

&&

.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
As of 320 AM Wednesday: By Thursday, a trough axis will linger
across central Tennessee in the wake of the Alberto remnants that
moved north to the Great Lakes. At low levels, flow will turn more
westerly and permit any upstream convection to run east across the
mountains and eventually the piedmont through late day. This should
support likely PoPs throughout the region, but the movement of the
convection should keep any additional rain from being excessive in
most areas.

Additional shortwave energy will sharpen the trough to the west on
Thursday night, with the main axis moving through the region on
Friday as an H5 low cuts off over the mid-Atlantic. Yet another
round of scattered to numerous convection may arrive from the west.
Temperatures will also climb to well above climo values, upper 80s
east of the mountains, in the warming westerly flow.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
As of 330 AM Wednesday: A surface cold front will settle southward
into the region on Saturday, but with a relative lull in the upper
forcing. Still, with low levels remaining moist another round of
scattered convection looks likely. Shallow ridging aloft will be
very brief through Saturday night before another vorticity maximum
in the NW flow crosses the region Sunday into Sunday night with yet
another round of scattered convection.

Deep layer northwest flow will finally set up on Monday and Tuesday
of next week between the offshore Atlantic trough and southern
plains ridging. Low level moisture will remain fairly abundant even
in the weak post frontal airmass Monday through Tuesday, with solid
diurnal PoPs continuing, especially over the mountains. Temperatures
return to near climo values, except for very mild mins.

&&

.AVIATION /08Z WEDNESDAY THROUGH SUNDAY/...
At KCLT and elsewhere: With the exception of VFR currently at KCLT,
a mixture of MVFR/IFR prevails across a majority of the FA this
morning due to low cigs and lingering light showers which continue
to move northward, especially across the upslope areas. Looking at
latest satellite/ob trends, do anticipate KCLT will deteriorate to
MVFR/IFR within the next hour or two due to low cigs. Similar to the
past few days, expect patchy areas of fog to develop as well towards
morning. Later this morning, do anticipate cigs to improve to MVFR,
and gradually to VFR this afternoon, as daytime heating allows for
the redevelopment of scattered showers and isolated thunderstorms.
Into the evening hours, expect convection to wane, with VCSH
prevailing. Again, a mixture of VFR/MVFR is expected towards the end
of the valid TAf period, with isolated areas of IFR possible. SSE
winds around 5 to 10 kts will prevail.

Outlook: Drier air begins to move into the area towards the end of
the week, with some degree of diurnal convection expected.

Confidence Table...

            07-13Z        13-19Z        19-01Z        01-06Z
KCLT       Med   76%     High  82%     High 100%     High  98%
KGSP       High  82%     High  89%     High  91%     High  90%
KAVL       High  87%     Med   77%     High 100%     High  91%
KHKY       Med   71%     Med   79%     High  83%     High  88%
KGMU       Med   79%     High  91%     High  91%     High  87%
KAND       Med   73%     High  93%     High  91%     High  89%

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 Thursday morning for GAZ010.
     Flash Flood Watch until 8 AM EDT this morning for GAZ017-018-
     026-028-029.
NC...Flash Flood Watch through Thursday morning for NCZ033-048>053-
     058-059-062>065-501>510.
     Flash Flood Watch until 8 AM EDT this morning for NCZ035>037-
     056-057-068>072-082.
SC...Flash Flood Watch through Thursday morning for SCZ001>003.
     Flash Flood Watch until 8 AM EDT this morning for SCZ004>014-
     019.

&&

SYNOPSIS...HG
NEAR TERM...SGL
SHORT TERM...HG
LONG TERM...HG
AVIATION...SGL
Hazardous weather outlook, May 30, 5:24 AM EDT, 1 hour 30 minutes before
Hazardous Weather Outlook
National Weather Service Greenville-Spartanburg SC
524 AM EDT Wed May 30 2018

GAZ017-018-026-028-029-NCZ035>037-056-057-068>072-082-SCZ004>014-019-
310930-
Habersham-Stephens-Franklin-Hart-Elbert-Alexander-Iredell-Davie-
Catawba-Rowan-Cleveland-Lincoln-Gaston-Mecklenburg-Cabarrus-Union-
Greater Oconee-Greater Pickens-Greater Greenville-Spartanburg-
Cherokee-York-Anderson-Abbeville-Laurens-Chester-Greenwood-
524 AM EDT Wed May 30 2018

...FLASH FLOOD WATCH IN EFFECT UNTIL 8 AM EDT THIS MORNING...

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.

   Flash Flood Watch.

Scattered to numerous thunderstorms will develop today and produce
occasional cloud-to-ground lightning and locally heavy rainfall. Any
thunderstorms will produce briefly gusty winds which could knock down
a few trees given the saturated soil conditions.

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

..Thursday...Heavy rain with flooding possible.
..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.

.SPOTTER INFORMATION STATEMENT...

Spotters should relay any reports of flooding, landslides, or wind
damage to the National Weather Service.

GAZ010-NCZ033-048>053-058-059-062>065-501>510-SCZ001>003-310930-
Rabun-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-
Greater Rutherford-Polk Mountains-Eastern Polk-Oconee Mountains-
Pickens Mountains-Greenville Mountains-
524 AM EDT Wed May 30 2018

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

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.

Scattered to numerous thunderstorms will develop today and produce
occasional cloud-to-ground lightning and locally heavy rainfall. Any
thunderstorms will produce briefly gusty winds which could knock down
a few trees given the saturated soil conditions.

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

..Thursday...Heavy rain with flooding possible.
..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.

.SPOTTER INFORMATION STATEMENT...

Spotters should relay any reports of flooding, landslides, or wind
damage to the National Weather Service.

HG

In the hours before

Local storm report, May 30, 4:28 AM EDT, 2 hours 26 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
428 AM EDT WED MAY 30 2018

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

1100 PM     DEBRIS FLOW      2 NW BAT CAVE           35.47N 82.31W
05/29/2018                   HENDERSON          NC   BROADCAST MEDIA

            REPORT OF A LARGE MUDSLIDE ON MIDDLEFORK RD NEAR
            MIDDLEFORK CHURCH WITH NUMEROUS OTHER SLIDES PARTIALLY OR
            FULLY BLOCKING ROAD.

&&

LACORTE
Local storm report, May 30, 4:48 AM EDT, 2 hours 6 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
448 AM EDT WED MAY 30 2018

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

1100 PM     FLASH FLOOD      3 WSW COLUMBUS          35.23N 82.26W
05/29/2018                   POLK               NC   BROADCAST MEDIA

            REPORT OF WARRIOR DRIVE CLOSED BETWEEN BAKER RD AND
            MEADOWLARK DRIVE DUE TO FLOOD WATERS.

&&

LACORTE
Local storm report, May 30, 4:49 AM EDT, 2 hours 5 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
449 AM EDT WED MAY 30 2018

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

1100 PM     FLASH FLOOD      6 NW COLUMBUS           35.29N 82.29W
05/29/2018                   POLK               NC   BROADCAST MEDIA

            REPORT OF GREEN RIVER COVE RD CLOSED DUE TO FLOOD WATERS.

&&

LACORTE
Local storm report, May 30, 4:51 AM EDT, 2 hours 3 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
451 AM EDT WED MAY 30 2018

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

1100 PM     FLASH FLOOD      5 W COLUMBUS            35.26N 82.30W
05/29/2018                   POLK               NC   BROADCAST MEDIA

            REPORT OF HOLBERT COVE ROAD NEAR COYOTE LANE CLOSED DUE
            TO FLOOD WATERS.

&&

LACORTE
Local storm report, May 30, 4:53 AM EDT, 2 hours 1 minute before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
453 AM EDT WED MAY 30 2018

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

1100 PM     FLASH FLOOD      SALUDA                  35.24N 82.35W
05/29/2018                   POLK               NC   BROADCAST MEDIA

            PORTIONS OF US 176 CLOSED DUE TO FLOOD WATERS BETWEEN
            SALUDA AND TRYON.

&&

LACORTE
Local storm report, May 30, 5:52 AM EDT, 1 hour 2 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
552 AM EDT WED MAY 30 2018

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

0545 AM     FLASH FLOOD      4 ENE OLD FORT          35.66N 82.11W
05/30/2018                   MCDOWELL           NC   COUNTY OFFICIAL

            MULTIPLE TRACTOR TRAILERS REPORTED STUCK IN FLOOD WATERS
            ON COLUMBIA CAROLINA ROAD IN THE GREENLEE COMMUNITY.

&&

HG

The office that day

Everything else NWS Greenville-Spartanburg, SC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 29, 8:56 PM EDTAreal Flood AdvisoryGSPRabun10 hr
May 30, 8:15 AM EDTFlash Flood WatchGSPHabersham42 hr
May 30, 8:58 AM EDTAreal Flood AdvisoryGSPHabersham6 hr
May 30, 9:56 AM EDTAreal Flood AdvisoryGSPFranklin, Hart, Stephens18 hr
May 30, 12:05 PM EDTAreal Flood WarningGSPRabun45 hr
May 30, 2:14 PM EDTSpecial Weather StatementGSPRabun31 min
May 30, 5:39 PM EDTAreal Flood AdvisoryGSPHabersham3 hr
May 30, 6:07 PM EDTSpecial Weather StatementGSPHart23 min
May 30, 6:39 PM EDTSpecial Weather StatementGSPHart51 min

Nearby

Flash Flood Warnings in Georgia, 2018Every flash flood warning in 2018

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.