Alert archive / North Carolina / Flash Flood Warnings in 2020
Flash Flood Warning 80, NWS Greenville-Spartanburg, SC
NWS Greenville-Spartanburg, SC issued this flash flood warning at Nov 12, 2020, 7:20 PM EST for Gaston County, Mecklenburg County, North Carolina. It was in force for 7 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, 7:20 PM EST (00:20 UTC)
- Expired
- Nov 13, 2020, 2:45 AM EST
- In force
- 7 hr
- Issued by
- NWS Greenville-Spartanburg, SC
- Area
- Storm-based polygon
- Damage threat
- Considerable
- Flood severity
- None
Counties Gaston County, NC, Mecklenburg County, NC
The radar
The Greer radar (KGSP), 123 km from the middle of the area, began a volume at 00:24 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 00:00Z, 0.3 hours before the alert went out and 129 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
- 32 J/kg
- Mixed-layer CIN
- -23 J/kg
- Mixed-layer LCL
- 593 m above ground
- 0-6 km bulk shear
- 47 kt
- 0-1 km storm-relative helicity
- -40 m²/s²
- 0-3 km storm-relative helicity
- 39 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
531
WGUS52 KGSP 130020
FFWGSP
NCC071-119-130745-
/O.NEW.KGSP.FF.W.0080.201113T0020Z-201113T0745Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Greenville-Spartanburg SC
720 PM EST Thu Nov 12 2020
The National Weather Service in Greenville-Spartanburg has issued a
* Flash Flood Warning for...
East Central Gaston County in the piedmont of North Carolina...
West Central Mecklenburg County in the piedmont of North Carolina...
* Until 245 AM EST Friday.
* At 720 PM EST, Rainfall accumulations of 3-7 inches since
Wednesday over the Catawba River watershed are causing significant
rises along the Catawba River reservoir chain tonight, including
at Mountain Island Lake. Additional rainfall will not occur for
the duration of this flood event. However, Duke Energy is moving
water through the river system in order to safely manage lake
levels and as a result, additional rises are forecast at Mountain
Island Lake. Duke Energy is projecting Mountain Island Lake may
exceed 103.0 feet later tonight before cresting later Friday
morning. This may cause areas of significant flooding along the
shoreline and especially immediately downstream of the dam along
the Catawba River in the Riverside Dr community. Therefore, to
adequately notify residents and other persons in the vicinity of
the Catawba River, a Flash Flood Warning has been issued. The
Flash Flood Warning will remain in effect until Mountain Island
Lake crests.
* This flood event is not currently expected to be as severe as the
event experienced in June 2019. Nevertheless, residents should
stay alert tonight and be prepared for levels above 103.0 feet
through tomorrow in case additional reservoir releases are
necessary.
* As of 640 PM, Mountain Island Lake is at 101.80 feet and rising
steadily.
Action/Advisory Stage: 101.50 feet
Minor Flood Stage: 103.00 feet
Moderate Flood Stage: 104.00 feet
FORECAST: Duke Energy projects the pool could exceed 103.00 feet
overnight tonight. Additional rises are possible overnight.
Residents are strongly encouraged to monitor lake levels and heed
guidance from Char-Meck Emergency Management.
IMPACTS: At 103.0 feet...Significant inundation of low-lying areas
is ongoing around Mountain Island Lake and downstream of the dam
along/near Riverside Dr. Some outbuilding inundation may begin.
Residents should have already completed the protection of property
adjacent to the lake and the Catawba River downstream and be taking
action to protect their homes. Residents downstream of the dam
should be prepared to evacuate and follow messaging from Char-Meck
Emergency Management.
At 104.0 feet...Moderate Flood Stage. Significant inundation of
outbuildings is beginning around Mountain Island Lake and downstream
of the dam along/near Riverside Dr. Residents downstream of the dam
should be completing preparations to evacuate and heeding guidance
from Char-Meck Emergency Management.
HAZARD...Flash flooding due to significant reservoir releases.
SOURCE...Emergency management, Duke Energy, and automated lake
gauges.
IMPACT...Life-threatening flash flooding Mountain Island Lake
and the Catawba River downstream of Mountain Island
Dam which may cause property damage and residential
evacuations.
* This Flash Flood Warning is exclusively for areas along Mountain
Island Lake and areas immediately downstream along the Catawba
River including Riverside Dr, Lake Dr, Riverhaven Dr, Hart Rd,
Beagle Club Rd, Drywall Dr, and other low-lying areas along the
Catawba River between Mountain Island Lake and Lake Wylie
including roadways adjacent to the river in Mecklenburg and Gaston
counties.
* For more information on lake levels, projections, or dam releases,
people are encouraged to visit http://lakes.duke-energy.com or
call 1-800-829-5253.
* Residents along and below Mountain Island Lake are encouraged to
stay aware of the latest updates from Charlotte-Mecklenburg
Emergency Management by signing up for Char-Meck alerts at:
www.charmeckalerts.org. Residents are encouraged to heed guidance
from local officials and Emergency Management on any potential
impacts to property and any evacuation orders. Drivers are
encouraged to heed any barricades and avoid all flooded areas.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Move to higher ground now. Act quickly to protect your life.
Be especially cautious at night when it is harder to recognize the
dangers of flooding.
&&
LAT...LON 3522 8102 3528 8102 3535 8098 3536 8095
3538 8094 3538 8092 3535 8091 3534 8091
3534 8093 3533 8097 3529 8098 3527 8100
3522 8100
FLASH FLOOD...OBSERVED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
$$
JMPWhat 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, 6:49 PM EST, 31 minutes earlier.
Area forecast discussion, Nov 12, 6:49 PM EST, 31 minutes before
Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
649 PM EST Thu Nov 12 2020
.SYNOPSIS...
A slow moving cold front will push east of the area tonight.
Drier air moving in from the west on Friday will control our
weather for most of the weekend.
&&
.NEAR TERM /THROUGH FRIDAY/...
As of 645 PM Thursday: Only isolated showers and patchy drizzle
remain this evening and should end overnight. However, there is a
lot of water flowing through creeks and streams into the main
rivers. Therefore, flood warnings and advisories will continue until
flood waters recede.
Deep layer drying has taken place as high pressure builds in behind
Eta. However, copious low level moisture remains in a general N to
NE flow. This will keep low clouds in place and expand them over
areas where they have cleared. Guidance suggests low clouds will be
more prevalent than dense fog, so have gone that route as well with
cloudy to mostly cloudy skies and patchy fog. The clouds and
moisture should keep lows around 15 degrees above normal. Temps will
be close to our record high minimums for Thursday. Westerly flow and
building high pressure will help scour out the low level moisture
with clearing taking place from west to east on Friday. Colder air
will be slower to infiltrate the area, so highs will be around 10
degrees above normal.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/...
As of 200 PM EST Thursday: Conditions will be dry and quiet Friday
night and Saturday as sfc high pressure pushes across the OH Valley
into the Mid-Atlantic and upper ridge stays in place over the
Southeast. The synoptic pattern changes into Sunday as sfc high
pressure moves off the Mid-Atlantic coast and upper troughing pushes
eastward across the central CONUS, ushering a cold front towards the
area. Per latest guidance, expect the front to push through the area
through late morning/early afternoon on Sunday. Guidance continues
to show little in the way of precipitation with this front, thus
have kept light showers confined to mainly the north of the I-85
corridor/west of the I-77 corridor. QPF amounts of a trace to a few
hundredths at most will be possible. Temps will remain normal on
Saturday, dropping to normal behind the front on Sunday.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
As of 230 PM EST Thursday: Per latest guidance, a cold front will be
east of the forecast area Sunday night with drier air infiltrating
into the area with NW flow. Expect dry and quiet conditions to
prevail through the remainder of the forecast period as sfc high
pressure builds in from the west with upper troughing setting up
across the eastern CONUS and upper ridging over the western CONUS,
both amplifying through the early part of the week. Guidance
continues to suggest a reinforcing dry cold front moving through
just before midweek. Temps will remain below normal through the
period.
&&
.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
At KCLT and elsewhere: Isolated showers and patchy drizzle may
linger this evening with MVFR vsby restrictions. Cigs will be the
bigger problem with IFR at KCLT falling to LIFR and staying there
through morning. Elsewhere, generally MVFR cigs this evening become
IFR to LIFR overnight, with some MVFR vsby. Conditions should improve
from west to east after daybreak as drier air and westerly winds
work into the area. KCLT will see restrictions the longest but will
be VFR by early afternoon. NE wind becomes light and variable
overnight then westerly during the day Friday. KAVL the exception
with NNW wind through the period, along with low end gusts for the
afternoon.
Outlook: Dry high pressure will keep mostly VFR conditions through
Saturday. A weak cold front could bring light rain and restrictions
Sunday. Dry high pressure and VFR returns Monday.
Confidence Table...
23-05Z 05-11Z 11-17Z 17-18Z
KCLT Med 72% Med 70% High 85% High 100%
KGSP High 89% Med 75% High 80% High 100%
KAVL High 89% High 95% Med 65% High 100%
KHKY High 94% Low 40% Med 75% High 100%
KGMU High 89% Med 75% High 80% High 100%
KAND Med 72% High 100% High 85% 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
&&
.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...None.
SC...None.
&&
SYNOPSIS...JPT
NEAR TERM...RWH
SHORT TERM...SGL
LONG TERM...SGL
AVIATION...RWH
CLIMATE...Hazardous weather outlook, Nov 12, 4:07 PM EST, 3 hours 13 minutes before
Hazardous Weather Outlook National Weather Service Greenville-Spartanburg SC 407 PM EST Thu Nov 12 2020 GAZ010-017-018-026-028-029-NCZ033-035>037-048>053-056>059-062>065- 068>072-082-501>510-SCZ001>014-019-132115- Rabun-Habersham-Stephens-Franklin-Hart-Elbert-Avery-Alexander- Iredell-Davie-Madison-Yancey-Mitchell-Swain-Haywood-Buncombe-Catawba- Rowan-Graham-Northern Jackson-Macon-Southern Jackson-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-Oconee Mountains- Pickens Mountains-Greenville Mountains-Greater Oconee- Greater Pickens-Greater Greenville-Spartanburg-Cherokee-York- Anderson-Abbeville-Laurens-Union SC-Chester-Greenwood- 407 PM EST Thu Nov 12 2020 This Hazardous Weather Outlook is for northeast Georgia, piedmont North Carolina, western North Carolina and upstate South Carolina. .DAY ONE...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.
In the hours before
Local storm report, Nov 12, 3:13 PM EST, 4 hours 7 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
313 PM EST THU NOV 12 2020
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0200 PM FLASH FLOOD MONROE 34.99N 80.54W
11/12/2020 UNION NC EMERGENCY MNGR
EMERGENCY MANAGEMENT REPORTS MULTIPLE ROADS CLOSED AND AT
LEAST TWO WATER RESCUES ACROSS THE COUNTY.
&&
LACORTELocal storm report, Nov 12, 3:51 PM EST, 3 hours 29 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
351 PM EST THU NOV 12 2020
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0805 AM NON-TSTM WND DMG 3 ESE GREENWOOD 34.18N 82.11W
11/12/2020 GREENWOOD SC EMERGENCY MNGR
EMERGENCY MNGR REPORTED TWO TREES DOWN ON HUNTING RD
&&Local storm report, Nov 12, 3:54 PM EST, 3 hours 26 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
354 PM EST THU NOV 12 2020
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0805 AM FLASH FLOOD 4 S GREENWOOD 34.14N 82.15W
11/12/2020 GREENWOOD SC EMERGENCY MNGR
EMERGENCY MNGR REPORTED ROAD CLOSURES DUE TO FLOODING
ON STILLWELL AND SCOTCH CROSS RD.
&&The office that day
Everything else NWS Greenville-Spartanburg, SC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Nov 12, 8:17 PM EST | Areal Flood Advisory | GSP | Burke, Caldwell | 12 hr |
| Nov 12, 8:38 PM EST | Areal Flood Warning | GSP | Catawba | 12 hr |
| Nov 12, 10:33 PM EST | Areal Flood Warning | GSP | Rowan | 18 hr |
| Nov 13, 3:03 AM EST | Areal Flood Warning | GSP | Gaston, Mecklenburg | 19 hr |
| Nov 13, 4:50 PM EST | Areal Flood Advisory | GSP | Rowan | 6 hr |
Nearby
Flash Flood Warnings in North 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.