Alert archive / South Carolina / Flash Flood Warnings in 2020
Flash Flood Warning 78, NWS Greenville-Spartanburg, SC
NWS Greenville-Spartanburg, SC issued this flash flood warning at Nov 12, 2020, 8:16 AM EST for Chester County, Union County, South Carolina. It was in force for 4 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
- Nov 12, 2020, 8:16 AM EST (13:16 UTC)
- Expired
- Nov 12, 2020, 12:00 PM EST
- In force
- 4 hr
- Issued by
- NWS Greenville-Spartanburg, SC
- Area
- Storm-based polygon
- Flood severity
- None
Counties Chester County, SC, Union County, SC
The radar
The Columbia radar (KCAE), 86 km from the middle of the area, began a volume at 13:17 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
Greensboro/Hi Pt, NC (KGSO), launched 12:00Z, 1.3 hours before the alert went out and 193 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.
- Mixed-layer CAPE
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 522 m above ground
- 0-6 km bulk shear
- 58 kt
- 0-1 km storm-relative helicity
- 21 m²/s²
- 0-3 km storm-relative helicity
- 172 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
439
WGUS52 KGSP 121316
FFWGSP
SCC023-087-121700-
/O.NEW.KGSP.FF.W.0078.201112T1316Z-201112T1700Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Greenville-Spartanburg SC
816 AM EST Thu Nov 12 2020
The National Weather Service in Greenville-Spartanburg has issued a
* Flash Flood Warning for...
Chester County in upstate South Carolina...
East Central Union SC County in upstate South Carolina...
* Until noon EST.
* At 816 AM EST, Doppler radar indicated thunderstorms producing
heavy rain making inroads into Chester county. Between 1 and 2
inches of rain have already fallen across Northwest Chester County
and excessive rain is expected to develop throughout the city of
Chester this morning. Flash flooding is ongoing or expected to
begin shortly.
HAZARD...Flash flooding caused by thunderstorms.
SOURCE...Doppler radar.
IMPACT...Flooding of small creeks and streams, urban areas,
highways, streets and underpasses as well as other
drainage and low lying areas.
* Some locations that will experience flash flooding include...
Chester, Fort Lawn, Lockhart, Richburg, Lowrys, Chester State
Park, Cornwell, Blackstock, Edgemoor and Leeds.
Additional rainfall amounts of 1 to 2 inches are possible in the
warned area.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
A Flash Flood Warning means that flooding is imminent or occurring.
If you are in the warned area move to higher ground immediately.
Residents living along streams and creeks should take immediate
precautions to protect life and property.
&&
LAT...LON 3482 8148 3482 8090 3470 8086 3456 8111
3457 8142
FLASH FLOOD...RADAR INDICATED
$$
CSHWhat 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 Nov 12, 7:01 AM EST, 1 hour 15 minutes earlier.
Area forecast discussion, Nov 12, 7:01 AM EST, 1 hour 15 minutes before
Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
701 AM EST Thu Nov 12 2020
.SYNOPSIS...
A slow moving cold front is expected to move across the region
today providing a focus for additional showers and storms. The
front should move off to the east tonight, followed by dry air
moving in from the west on Friday. High pressure moving past to
the north should control our weather for most of the weekend.
&&
.NEAR TERM /THROUGH TONIGHT/...
As of 650 AM Thursday: The cold front is about half way thru
the forecast area attm, slowly pushing east. So all the heavy
rain has set up across the eastern zones. Rain rates/updrafts
have trended upward along the eastern edge of the precip band,
with highest rates from Greenwood County thru the Charlotte metro
area to the Triad. Flash flooding remains a real concern in those
areas. To the west, with the rain pulling out, have removed some
of the western zones from the FFA. The French Broad Valley and the
Northern Mountains have been left in the FFA due to ongoing runoff,
but will probably be able to be canceled with the next update.
From the 330 AM update...A leading shortwave trough exiting a broad
longwave 500 mb trough across the central CONUS will produce strong
upper divergence atop the forecast area thru this morning. The
mid and upper level support will be coupled with a slow-moving
cold front, which has already push into the NC mountains and will
continue to advance east thru the day. PWATs are still running at
record levels along and ahead of the front. And forecast soundings
show very deep warm cloud layers and unidirectional flow that
supports training convection. All this to say that the flood
threat is probably at its highest over the next 6-8 hours or so,
especially along and east of the Blue Ridge Escarpment. No changes
were made to the Flood Watch with this update, but some of the
counties in the western and central NC mountains may be able to be
canceled with the next update. As a frontal band of heavy showers
(and possibly some isolated embedded tstms) will set up over the
I-77 corridor right around daybreak. Guidance shows an additional
1-3", with locally higher amounts.
Around noon...the heaviest convection should begin to exit to our
east, with Union County, NC, being the last to clear out. Low-level
flow behind the front will be fairly weak, and forecast soundings
show low clouds stubbornly holding on thru the aftn. The exceptions
will be in the western mountains and the Upper Savannah Valley,
which could see more sunshine before sunset. Temps will be tricky,
as too many breaks in the clouds could allow temps to shoot
up several degrees warmer than the current forecast. For now,
think they will range from the lower 70s northeast to upper 70s
southwest. Dewpts will come down from the lower 70s to mid 60s,
so it will still feel fairly humid.
Tonight...dry air continues to filter in from the west, but
low-level moisture lingers. It could be a good fog night for some
areas, but high pressure building in from the west and T.C. Eta
tracking along the GA/SC coast will keep a pressure gradient
atop the area. So still think it will be more of a low stratus
deck that forms with patchy fog, rather than widespread dense
fog tonight. Temps will start falling like usual around sunset,
but may not get below our record high minimums at any of our
climate sites before midnight. Lows will be mainly in the 50s,
still about 14-18 deg above normal.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
As of 138 AM EST Thursday: Autumn is on track to return to the
western Carolinas and northeast Georgia for the weekend. The
moisture gradient should be across the fcst area at daybreak Friday
and is expected to push east during the day with a modest WNW flow
at 850mb, ushering in the dry air associated with high pressure to
our west. A flat upper ridge will carry that surface high past to
the north through Saturday, giving us a classic autumn day with
temperatures right around normal. The high will migrate off the
Mid-Atlantic coast Saturday night, with some weak moisture return by
daybreak Sunday. Think the guidance is a little premature suggesting
that some upslope light precip might develop around daybreak Sunday
near the Escarpment. Prefer to keep the fcst dry for now.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
As of 321 AM EST Thursday: A broad upper trof moving east across
the Plains will push a cold front in our direction on Sunday, but
forcing and moisture return looks minimal. Guidance was generally
accepted with a chance of showers ramping up over the mtns/foothills
through the afternoon. The front should move quickly through the
region given such a low amplitude upper pattern, so we dry out
again Sunday night as the upper trof axis moves past. After that,
high pressure will build in from the west and dominate through
Tuesday, before a dry reinforcing front moves through followed
by the next surface high building in from the NW for the rest of
the period. Temperatures will be on the order of a category below
normal for most of the period.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
At KCLT and elsewhere: At time of 12z TAF issuance, a slow-moving
cold front had just passed thru KHKY and was about to cross the
Upstate TAF sites. Conditions have briefly improved in those sites
in the wake of heavy rain showers, but will likely return to IFR or
at least low MVFR for a few hours this morning. The front will pass
thru KCLT around 14z, shifting the winds from S to N. The line of
heavy showers and embedded tstms should start to shift east in the
14-17z time frame. Drying starts to take over after 18z, but not
enough to scour out the low cigs, which look to remain generally
MVFR, except for some scattering out in the Upstate and at KAVL. The
low cigs will likely persist tonight as well, with guidance showing
LIFR possible east of the mountains overnight. There is some hint
in the guidance that winds may become light enough to allow fog
to form, but overall, it looks mostly like a stratus event tonight.
Outlook: Dry high pressure will finally build in Friday, scouring
out the low clouds and any fog that's around Friday morning,
bringing back mostly VFR conditions thru the weekend.
Confidence Table...
12-18Z 18-24Z 00-06Z 06-12Z
KCLT High 87% High 88% Med 77% Med 79%
KGSP Med 77% High 87% High 80% Med 73%
KAVL Med 79% High 82% High 88% Med 74%
KHKY Med 76% High 94% High 83% Med 77%
KGMU Med 73% High 85% Med 76% Med 73%
KAND Med 74% High 89% Med 73% Med 73%
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 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
RECORDS FOR 11-13
MAX TEMPERATURE MIN TEMPERATURE
STATION HIGH LOW HIGH LOW
------- ---------- ---------- ---------- ----------
KAVL 75 1964 32 1906 58 1929 13 1911
1958
1938
KCLT 81 1931 40 1920 63 1879 21 2013
KGSP 81 1909 40 1920 61 1929 20 1906
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...None.
NC...Flood Watch until 7 PM EST this evening for NCZ033-035>037-049-
050-053-056-057-064-065-068>072-082-501>510.
SC...Flood Watch until 7 PM EST this evening for SCZ003-006>009-
012>014.
&&
SYNOPSIS...PM
NEAR TERM...ARK
SHORT TERM...PM
LONG TERM...PM
AVIATION...ARK
CLIMATE...Hazardous weather outlook, Nov 12, 5:47 AM EST, 2 hours 29 minutes before
Hazardous Weather Outlook National Weather Service Greenville-Spartanburg SC 547 AM EST Thu Nov 12 2020 NCZ033-035>037-049-050-053-056-057-064-065-068>072-082-501>510- SCZ003-006>009-012>014-131100- Avery-Alexander-Iredell-Davie-Yancey-Mitchell-Buncombe-Catawba-Rowan- 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- Greenville Mountains-Greater Greenville-Spartanburg-Cherokee-York- Laurens-Union SC-Chester- 547 AM EST Thu Nov 12 2020 ...FLOOD WATCH IN EFFECT THROUGH THIS EVENING... This Hazardous Weather Outlook is for 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...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. GAZ010-017-018-026-NCZ048-051-052-058-059-062-063-SCZ001-002-004-005- 131100- Rabun-Habersham-Stephens-Franklin-Madison-Swain-Haywood-Graham- Northern Jackson-Macon-Southern Jackson-Oconee Mountains- Pickens Mountains-Greater Oconee-Greater Pickens- 547 AM EST Thu Nov 12 2020 This Hazardous Weather Outlook is for northeast Georgia, western North Carolina and upstate South Carolina. .DAY ONE...Today and tonight. No hazardous weather is expected at this time. .DAYS TWO THROUGH SEVEN...Friday through Wednesday. No hazardous weather is expected at this time. .SPOTTER INFORMATION STATEMENT... None. GAZ028-029-SCZ010-011-019-131100- Hart-Elbert-Anderson-Abbeville-Greenwood- 547 AM EST Thu Nov 12 2020 This Hazardous Weather Outlook is for northeast Georgia and upstate South Carolina. .DAY ONE...Today and tonight. Showers and a few thunderstorms are expected this morning. The main threats will be heavy rain that may result in localized flash flooding, and a few cloud-to-ground lightning strikes. The showers and storms should move to the east by early afternoon. .DAYS TWO THROUGH SEVEN...Friday through Wednesday. Hazardous weather is not expected at this time. .SPOTTER INFORMATION STATEMENT... None.
In the hours before
Special weather statement, Nov 12, 6:31 AM EST, 1 hour 45 minutes before
Special Weather Statement
National Weather Service Greenville-Spartanburg SC
631 AM EST Thu Nov 12 2020
SCZ012-013-121230-
Laurens SC-Union SC-
631 AM EST Thu Nov 12 2020
...A STRONG THUNDERSTORM WILL IMPACT SOUTHEASTERN LAURENS AND UNION
COUNTIES UNTIL 730 AM EST...
At 630 AM EST, Doppler radar was tracking a strong thunderstorm 13
miles southeast of Laurens, or 5 miles northeast of Cross Hill,
moving northeast at 25 mph.
Locations to be impacted include...
Union, Clinton, Monarch Mill, Joanna, Buffalo, Jonesville, Cross
Hill, Carlisle, Rose Hill State Park and Lake Greenwood.
Wind gusts up to 40 mph and very heavy rainfall rates up to 2 inches
per hour will be possible in these areas. If the rain continues, a
Flood Warning may be issued for all or part of the area.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Gusty winds can blow down trees that are dead, or that have weakened
root systems. Outdoor furniture and similar items can be tossed
around if not anchored. Seek shelter indoors.
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 3428 8205 3460 8185 3484 8178 3491 8171
3490 8165 3488 8163 3489 8159 3486 8148
3483 8146 3482 8149 3476 8146 3473 8149
3472 8146 3460 8142 3449 8147 3445 8154
3453 8164 3437 8178 3430 8190 3421 8194
TIME...MOT...LOC 1130Z 212DEG 21KT 3434 8190
MOORELocal storm report, Nov 12, 6:57 AM EST, 1 hour 19 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
657 AM EST THU NOV 12 2020
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0615 AM FLASH FLOOD 4 S VALDESE 35.69N 81.56W
11/12/2020 BURKE NC SOCIAL MEDIA
REPORTS OF FLOODED ROADWAYS AND A FEW LANDSLIDES ACROSS
THE COUNTY, ESPECIALLY NEAR MORGANTON AND VALDESE. EVENTS
ARE ONGOING.
&&
LACORTELocal storm report, Nov 12, 7:10 AM EST, 1 hour 6 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
710 AM EST THU NOV 12 2020
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0600 AM FLASH FLOOD HIDDENITE 35.90N 81.09W
11/12/2020 ALEXANDER NC 911 CALL CENTER
MULTIPLE WATER RESCUES, 15 TO 20, ACROSS EASTERN PORTIONS
OF THE COUNTY.
&&
LACORTELocal storm report, Nov 12, 7:17 AM EST, 59 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
717 AM EST THU NOV 12 2020
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0700 AM FLASH FLOOD 5 NNE MORGANTON 35.81N 81.66W
11/12/2020 BURKE NC TRAINED SPOTTER
REPORT OF FLOODED ROADWAY IN FRONT OF CHESTERFIELD FIRE
DEPARTMENT. UP TO 2 FEET OF WATER ON THE ROAD.
&&
LACORTELocal storm report, Nov 12, 7:45 AM EST, 31 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
745 AM EST THU NOV 12 2020
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0720 AM FLASH FLOOD 6 SSE LENOIR 35.83N 81.50W
11/12/2020 CALDWELL NC AMATEUR RADIO
REPORT OF WATER ACROSS ROADWAY CAUSING ROAD CLOSURE NEAR
THE INTERSECTION OF CAJAH MOUNTAIN RD AND HORSESHOE BEND
RD.
&&
LACORTELocal storm report, Nov 12, 8:04 AM EST, 12 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
804 AM EST THU NOV 12 2020
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0750 AM FLASH FLOOD 2 S PAW CREEK 35.24N 80.94W
11/12/2020 MECKLENBURG NC EMERGENCY MNGR
ROAD FLOODED ACROSS I-85 NORTH AND SOUTHBOUND NEAR LITTLE
ROCK ROAD. SEVERAL CARS IN STANDING WATER WITH FIRE
RESCUE ASSISTING INDIVIDUALS OUT OF CARS.
&&
LACORTEThe office that day
Everything else NWS Greenville-Spartanburg, SC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Nov 11, 8:17 PM EST | Areal Flood Advisory | GSP | Laurens | 3 hr |
| Nov 11, 8:45 PM EST | Special Weather Statement | GSP | Cherokee | 45 min |
| Nov 11, 9:15 PM EST | Areal Flood Advisory | GSP | Cherokee, Spartanburg | 3 hr |
| Nov 12, 2:46 AM EST | River Flood Advisory | GSP | Cherokee, York | 16 hr |
| Nov 12, 5:10 AM EST | Areal Flood Advisory | GSP | Abbeville, Anderson, Cherokee, Greenville, Greenwood, Laurens and 2 more | 3 hr |
| Nov 12, 5:54 AM EST | Areal Flood Advisory | GSP | Cherokee, Chester, Laurens, Spartanburg, Union, York | 3 hr |
| Nov 12, 6:31 AM EST | Special Weather Statement | GSP | Union | 59 min |
| Nov 12, 6:42 AM EST | Flash Flood Warning | GSP | Greenwood, Laurens | 3 hr |
| Nov 12, 6:46 AM EST | Flash Flood Warning | GSP | Cherokee, Union, York | 3 hr |
| Nov 12, 7:40 AM EST | Flash Flood Warning | GSP | York | 10 hr |
| Nov 12, 8:42 AM EST | Areal Flood Advisory | GSP | Greenville, Spartanburg | 14 hr |
| Nov 12, 3:34 PM EST | Areal Flood Warning | GSP | York | 6 hr |
| Nov 12, 6:29 PM EST | River Flood Warning | GSP | Cherokee, York | 15 hr |
Nearby
Flash Flood Warnings in South Carolina, 2020Every flash flood warning in 2020
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.