Alert archive / North Carolina / Flash Flood Warnings in 2020

Flash Flood Warning 32, NWS Greenville-Spartanburg, SC

May 19, 2020Polk County, Rutherford County, North Carolina

NWS Greenville-Spartanburg, SC issued this flash flood warning at May 19, 2020, 2:02 PM EDT for Polk County, Rutherford County, North Carolina. It was in force for 3 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 19, 2020, 2:02 PM EDT (18:02 UTC)
Expired
May 19, 2020, 5:00 PM EDT
In force
3 hr
Issued by
NWS Greenville-Spartanburg, SC
Area
Storm-based polygon
Flood severity
None

Counties Polk County, NC, Rutherford County, NC

The radar

The Greer radar (KGSP), 80 km from the middle of the area, began a volume at 18:05 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, 6.0 hours before the alert went out and 182 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, Greensboro/Hi Pt, NC at 12:00Z on 2020-05-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1 joules per kilogram.LCLEL10008507005003002001001 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, Greensboro/Hi Pt, NC at 12:00Z on 2020-05-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 238 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
1 J/kg
Mixed-layer CIN
0 J/kg
Mixed-layer LCL
486 m above ground
0-6 km bulk shear
38 kt
0-1 km storm-relative helicity
238 m²/s²
0-3 km storm-relative helicity
311 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.0

Open this sounding in Storm Lab

The text

As transmitted.

280 
WGUS52 KGSP 191802
FFWGSP
NCC149-161-192100-
/O.NEW.KGSP.FF.W.0032.200519T1802Z-200519T2100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Greenville-Spartanburg SC
202 PM EDT Tue May 19 2020

The National Weather Service in Greenville-Spartanburg has issued a

* Flash Flood Warning for...
  Rutherford County in western North Carolina...
  Southeastern Polk County in western North Carolina...

* Until 500 PM EDT.

* At 201 PM EDT, Doppler radar and automated gauges indicated
  thunderstorms producing heavy rain across the warned area. Flash 
  flooding is ongoing or expected to begin shortly, especially 
  throughout Greater Rutherfordton and select tributaries of the 
  Broad River.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar and automated gauges.

  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 flooding include...
  Forest City, Rutherfordton, Spindale, Ellenboro, Bostic, Cliffside,
  Henrietta, Green Creek, Harris and Sunshine.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Excessive runoff from heavy rainfall will cause flooding of small
creeks and streams, highways, and underpasses. Addditionally, country
roads and farmlands along the banks of creeks, streams, and other
low-lying areas are subject to flooding.

&&

LAT...LON 3559 8171 3558 8169 3538 8170 3518 8177
      3519 8210 3553 8194 3554 8185 3557 8183
      3558 8181 3558 8180 3559 8179 3559 8177
      3560 8177 3561 8172

FLASH FLOOD...RADAR AND GAUGE INDICATED

$$
1 follow-up statement
795 
WGUS72 KGSP 191944
FFSGSP

Flash Flood Statement
National Weather Service Greenville-Spartanburg SC
344 PM EDT Tue May 19 2020

NCC149-161-192100-
/O.CON.KGSP.FF.W.0032.000000T0000Z-200519T2100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Rutherford NC-Polk NC-
344 PM EDT Tue May 19 2020

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 500 PM EDT FOR
RUTHERFORD AND SOUTHEASTERN POLK COUNTIES...

At 341 PM EDT, Excessive runoff and high water conditions lingered 
across the warned area where rainfall amounts this afternoon has 
averged 3 to 4 inches.

HAZARD...Flash flooding caused by heavy rain.

SOURCE...Radar and automated gauges.

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 flooding include...
Forest City, Rutherfordton, Spindale, Ellenboro, Bostic, Cliffside,
Henrietta, Green Creek, Harris and Sunshine.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Most flood deaths occur in vehicles. Do not attempt to cross
water-covered roadways, bridges, or low-level crossings. Only a few
inches of rapidly flowing water can carry away your vehicle. It is
not worth the risk. Please TURN AROUND, DON'T DROWN.

&&

LAT...LON 3559 8171 3558 8169 3538 8170 3518 8177
      3519 8210 3553 8194 3554 8185 3557 8183
      3558 8181 3558 8180 3559 8179 3559 8177
      3560 8177 3561 8172

FLASH FLOOD...RADAR AND GAUGE INDICATED

$$

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 19, 1:47 PM EDT, 15 minutes earlier.

Area forecast discussion, May 19, 1:47 PM EDT, 15 minutes before
Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
147 PM EDT Tue May 19 2020

.SYNOPSIS...
A large upper low will linger over the Tennessee Valley Region
through mid week as it slowly weakens. This weather pattern will
generate multiple rounds of moderate to heavy rain across much of
our region that continues into the latter half of the week. More
typical late spring weather is expected to return over the weekend.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 145 PM EDT Tuesday: Main update for the 18Z TAF issuance along
with minor adjustments made to temperatures to coincide with latest
trends as the rest of the near term forecast remains on track.
Latest radar imagery continues to depict showers, along with a few
thunderstorms now as well, moving northward across the area as
previously anticipated. Current temperatures range from the mid to
upper 60s.

A Flash Flood Watch remains in effect for portions of the area.
Please see latest Public Information Statement regarding the
increasing threat for landslides and debris flows across the
mountains and foothills over the next few days.

Previous discussion: The large h5 low will continue to gradually
drift south today and tonight as it maintains a nearly symmetrical
appearance.  By the end of the near-term period it will be centered
just to our west and over Eastern TN/Northern GA. At the sfc, the
main low will not move much today/tonight with the heavier precip
bands expected to shift more to the northern part of the CWFA, say
in the vicinity of the I-40 corridor, as the low-lvl flow becomes
more NELY later this aftn. The resulting hybrid wedge-like
configuration will persist well into Wednesday with the north to
south temperature gradient strengthening each day. As for the
thunderstorm potential today and tonight, model profiles generate
less instability compared to yesterday with weaker lapse rates from
the warmer air aloft. Therefore, it's pretty unlikely that any
thunderstorms will reach severe criteria.

&&

.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
As of 323 am EDT Tuesday: We will remain under the influence of a
strong upper low through the middle part of the week. The latest
guidance has the center of this feature a little bit farther south
on Wednesday, which brings more of a focus for heavy precip maybe
a bit farther down the Escarpment toward northeast GA. The precip
amounts down the chain are not appreciably higher yet, so the
southwest extent of the watch still looks well-placed. Meanwhile,
as the low makes its closest wobble to the srn Appalachians, the
main plume of moisture should translate slowly eastward across
the fcst area during the day and into Wednesday evening. The low
level convergence will orient itself in a SE to NW fashion, pointed
right at the NC mountains during this period, with an anomalously
strong easterly flow transporting copious moisture up into northwest
NC. This time period will be of great concern for ongoing flooding
across the NC mtns and foothills, with areas outside the mtns and
particularly the Charlotte metro area having perhaps their highest
threat for new flooding. Think it wise to expand the Watch now
to cover the remainder of the Charlotte metro area. Over the mtns
and near the Escarpment, our risk for landslides and debris flows
may also maximize Wednesday and Wednesday evening. Temperatures
through this period will remain well below normal because of the
heavy rain and extensive cloudiness. The conveyor belt of moisture
should get slowly pushed off to the northeast Wednesday night
and Thursday morning and some drier air should wrap in across
northeast Georgia as well. Thus, our precip probs should start
to tail off on Thursday, although they remain high across the NC
part until Thursday night. The new ECMWF is a bit more optimistic
with a quicker timing of moving drier air into the region, so a
downward trend on the precip chances was employed. Temps should
rebound on Thursday as well.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
As of 210 AM EDT Tuesday: Model discrepancies remain as to the
eventual demise or departure of the upper low on Friday, with the
GFS still lifting it out over the OH Valley on a northeast track by
sunrise, but the ECMWF taking a slower eastern track and keeping it
close enough to our north to keep us under a stronger cyclonic flow
aloft. Either way, forcing and moisture should be on the downswing
on Friday, but with enough left over for diurnally enhanced precip
probabilities that favor the mtns. Even in the wake of the low,
model differences abound, and thus confidence suffers. Some kind of
upper ridging is expected to take hold over the weekend, but will
it be more amplified like the ECMWF or flatter like the GFS. The
former favors a purely diurnal precip scenario no better than a
summertime 30 mtns/20 Piedmont percentage, but the latter would
see a steady train of weak upper waves moving thru the flat ridge
to keep precip chances fluctuating but not completely going away
at night over the mtns. Both scenarios favor above normal temps
and a relatively humid air mass. The fcst will keep a diurnally
modulated precip forecast until a clearer signal is seen.

&&

.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
At KCLT and Elsewhere: A mixture of VFR/MVFR/IFR/LIFR prevails
across the area this afternoon with ongoing scattered showers and
lowered cigs. Intermittent periods of improving flight restrictions
will be possible through this evening per latest satellite trends.
Expect increasing potential for VCTS/-TSRA this afternoon embedded
with heavy rain showers. Expect deteriorating flight restrictions
tonight and into Wednesday with low cigs, patchy fog, and showers.
East-northeasterly winds, gusty at times, will prevail at the NC TAF
sites, with the southeasterly winds at the SC sites gradually
becoming east-northeasterly later this afternoon into this evening.

Outlook: Showers and thunderstorms will continue into Wednesday and
possibly Thursday, creating flight restrictions. Expect a gradual
drying trend towards the end of the week.

Confidence Table...

            17-23Z        23-05Z        05-11Z        11-12Z
KCLT       High 100%     High  85%     Med   75%     High  94%
KGSP       High 100%     Low   35%     High  90%     Med   69%
KAVL       High  81%     Low   55%     High  90%     Med   69%
KHKY       High 100%     High  95%     High 100%     High  94%
KGMU       Med   75%     Med   60%     Med   65%     Med   75%
KAND       High  87%     High  95%     Med   65%     Med   64%

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...None.
NC...Flash Flood Watch through Thursday morning for NCZ033-035>037-
     049-050-053-056-057-064-065-068>072-082-501>510.
SC...Flash Flood Watch through Thursday morning for SCZ002-003-
     005>010-013-014.

&&

SYNOPSIS...JPT
NEAR TERM...JPT/12
SHORT TERM...PM
LONG TERM...PM
AVIATION...12
Hazardous weather outlook, May 19, 10:04 AM EDT, 3 hours 58 minutes before
Hazardous Weather Outlook
National Weather Service Greenville-Spartanburg SC
1004 AM EDT Tue May 19 2020

NCZ033-035>037-049-050-053-056-057-064-065-068>072-082-501>510-
SCZ002-003-005>010-013-014-201415-
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-
Pickens Mountains-Greenville Mountains-Greater Pickens-
Greater Greenville-Spartanburg-Cherokee-York-Anderson-Union SC-
Chester-
1004 AM EDT Tue May 19 2020

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

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.

   Flash Flood Watch.

In addition to the heavy rainfall threat, scattered thunderstorms
are likely again today and tonight. The main threats from these
thunderstorms will be brief, gusty winds and dangerous cloud to
ground lightning.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday.

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

   Flash Flood Watch.

.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.

GAZ010-017-018-026-028-029-NCZ048-051-052-058-059-062-063-SCZ001-004-
011-012-019-201415-
Rabun-Habersham-Stephens-Franklin-Hart-Elbert-Madison-Swain-Haywood-
Graham-Northern Jackson-Macon-Southern Jackson-Oconee Mountains-
Greater Oconee-Abbeville-Laurens-Greenwood-
1004 AM EDT Tue May 19 2020

This Hazardous Weather Outlook is for northeast Georgia, western
North Carolina and upstate South Carolina.

.DAY ONE...Today and tonight.

There is the increasing likelihood of excessive rainfall today and
tonight, as periodic waves of showers and thunderstorms are expected
to move across the region. Across the mountains, the threat for
landslide activity will also increase. In addition to the heavy
rainfall threat, scattered thunderstorms are likely again today and
tonight. The main threats from these thunderstorms will be brief,
gusty winds and dangerous cloud to ground lightning.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday.

Substantial rainfall is expected again on Wednesday and early Thursday,
as periodic waves of showers and thunderstorms move across the region.
The threat for flooding will remain elevated through Thursday. Across
the mountains, the threat for landslide activity may also increase
through Wednesday. Eventually, the flood threat along main stem
rivers will also increase and remain elevated through Thursday.

.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.

JPT/12

In the hours before

Local storm report, May 19, 12:56 PM EDT, 1 hour 6 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1256 PM EDT TUE MAY 19 2020

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

1240 PM     FLOOD            4 SSW OLD FORT          35.58N 82.20W
05/19/2020                   MCDOWELL           NC   EMERGENCY MNGR

            LITTLE CROOKED CREEK OVERFLOWING ONTO ROY MOORE RD.

&&

17

The office that day

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

IssuedProductOfficeCountiesLasted
May 18, 9:19 PM EDTSpecial Weather StatementGSPUnion41 min
May 18, 10:38 PM EDTSpecial Weather StatementGSPUnion52 min
May 18, 11:44 PM EDTAreal Flood AdvisoryGSPUnion6 hr
May 19, 1:44 AM EDTSpecial Weather StatementGSPUnion46 min
May 19, 3:41 AM EDTAreal Flood AdvisoryGSPAlexander, Burke, Caldwell, Catawba3 hr
May 19, 12:18 PM EDTAreal Flood WarningGSPBuncombe, Henderson, Polk, Rutherford9 hr
May 19, 12:27 PM EDTAreal Flood WarningGSPMcDowell10 hr
May 19, 1:23 PM EDTFlash Flood WarningGSPMcDowell, Polk, Rutherford3 hr
May 19, 4:44 PM EDTAreal Flood WarningGSPPolk, Rutherford3 hr
May 19, 5:36 PM EDTAreal Flood AdvisoryGSPAvery, Burke, Caldwell, McDowell5 hr
May 19, 7:26 PM EDTAreal Flood AdvisoryGSPPolk, Rutherford3 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.