Alert archive / North Carolina / Flash Flood Warnings in 2018

Flash Flood Warning 14, NWS Greenville-Spartanburg, SC

May 18, 2018Avery County, Caldwell County, North Carolina

NWS Greenville-Spartanburg, SC issued this flash flood warning at May 18, 2018, 10:25 PM EDT for Avery County, Caldwell County, North Carolina. It was in force for 4 hr. 2 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
May 18, 2018, 10:25 PM EDT (02:25 UTC)
Expired
May 19, 2018, 2:15 AM EDT
In force
4 hr
Issued by
NWS Greenville-Spartanburg, SC
Area
Storm-based polygon
Flood severity
None

Counties Avery County, NC, Caldwell County, NC

The radar

The Greer radar (KGSP), 135 km from the middle of the area, began a volume at 02:27 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.

What was reported inside it

TimeReportWhereRemark
May 18, 10:30 PM EDTFLASH FLOOD5 Ene Newland, NCCOUNTY REPORTS ROAD CLOSURES DUE TO FLOODING NEAR GRANDFATHER MOUNTAIN AREA OF HIGHWAYS 105 AND 184.
May 18, 10:45 PM EDTFLASH FLOOD5 Sw Globe, NCNUMEROUS ROAD CLOSURES ALL AROUND MORTIMER DUE TO FLOODING OF WILSON CREEK.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

Did it verify

Verified. The Iowa Environmental Mesonet's Cow matched 3 storm reports to this flash flood warning; the first came 5 minutes after it went out.

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, 2.4 hours before the alert went out and 172 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 00:00Z on 2018-05-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 112 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, Greensboro/Hi Pt, NC at 00:00Z on 2018-05-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 38 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
112 J/kg
Mixed-layer CIN
-3 J/kg
Mixed-layer LCL
649 m above ground
0-6 km bulk shear
19 kt
0-1 km storm-relative helicity
38 m²/s²
0-3 km storm-relative helicity
47 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

975 
WGUS52 KGSP 190225
FFWGSP
NCC011-027-190615-
/O.NEW.KGSP.FF.W.0014.180519T0225Z-180519T0615Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Greenville-Spartanburg SC
1025 PM EDT FRI MAY 18 2018

The National Weather Service in Greenville-Spartanburg has issued a

* Flash Flood Warning for...
  Northwestern Caldwell County in western North Carolina...
  Eastern Avery County in western North Carolina...

* Until 215 AM EDT.

* At 1017 PM EDT, very serious flooding and high water conditions 
  continue across northwest Caldwell County and eastern Avery 
  County. Radar and rain gages are indicating some 4 to 6 inch 
  rainfall totals in these areas over the past six hours and 
  additional showers and thunderstorms redeveloping from the south 
  will produce additional rainfall at rates of one-half to one inch 
  per hour into the early morning hours. Flooding will persist in 
  areas already flooded and new flash flooding will likely develop.

* Some locations that will experience flooding include...Newland, 
  Blowing Rock In Caldwell County, Banner Elk, Beech Mountain In 
  Avery County, Crossnore, Sugar Mountain, Seven Devils, Grandfather 
  Mountain State Park, B.R. Parkway-Linville Falls To Grandfather 
  and Edgemont. 

Major flood stage will be reached along Wilson's Creek at Edgemont. 
This will cause additional homes adjacent to Wilson's Creek to 
flood. Residential flooding is likely near the intersection of 
Laurel Lane and Edgemont Road. Flooding will continue along Old 
Johns River Road and Wilson Creek Road. Mudslides may develop in any 
areas with steep terrain.

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. Be especially 
cautious at night when it is harder to recognize the dangers of 
flooding.

Numerous roads, parking lots and bridges will be threatened by heavy
rain and rapidly rising streams and creeks. 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.

The additional heavy rain will increase the risk of landslides,
especially in areas where slides have occurred in the past. Be
especially alert if you are near a stream, especially at the base of
a mountain or in a cove. Watch for loose-moving soil and rocks or a
sudden increase in streamflow. Leave the area quickly if this is
observed. When driving along roads where the terrain is steep or
rocky, watch and listen for falling rocks, mud, trees and other
debris.

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 3619 8188 3619 8186 3616 8183 3611 8181
      3612 8169 3612 8155 3588 8171 3593 8175
      3593 8178 3595 8178 3595 8180 3597 8182
      3598 8187 3600 8190 3595 8196 3621 8191

$$

HG

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 18, 8:12 PM EDT, 2 hours 13 minutes earlier.

Area forecast discussion, May 18, 8:12 PM EDT, 2 hours 13 minutes before
Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
812 PM EDT Fri May 18 2018

.SYNOPSIS...
The threat for numerous showers and a few thunderstorms will linger
into Saturday as a slow moving low pressure system impacts our
region. Locally heavy rainfall will remain possible until the low
departs. High temperatures will be near to just above normal and low
temperatures about ten degrees above normal.

&&

.NEAR TERM /THROUGH SATURDAY/...
As of 810 PM EDT Friday: Main update for the 00Z TAF issuance
along with minor tweaks made to temperatures to coincide with
latest trends. The Flash Flood Watch has been updated with this
forecast update as well. Macon, Rabun, Oconee and Jackson
counties are no longer included within the watch area. The rest
of the counties previously included within the watch area
remain under a Flash Flood Watch now through early Saturday
morning.

Showers and isolated thunderstorms continue to move/redevelop
across the NC mountains and northern foothills attm, with
torrential rainfall and already saturated grounds favoring
flooding issues. Elsewhere, latest radar depicts another round
of showers and thunderstorms moving into the southern portions
of the FA, gradually moving towards the I-77 corridor. Expect
this shower and thunderstorm activity to continue well
throughout the evening hours, however latest guidance continues
to not have the best handle on the evolving situation, thus
leaving confidence on coverage of activity overnight low attm.

Otherwise, a broad upper level trof continues to spin across the
South maintaining deep and moist s/ly flow into the FA. This pattern
will change little during the period, with some n/ly lift expected
by Sat afternoon. Expect less thunder chances overnight, yet still a
high PoP -shra thru the morning with a continued hydro threat across
the srn BR. Thunderstorms will once again be possible by mid-day Sat
within a persistent and high confidence synoptic pattern. Mins
overnight will be held abt 10 degrees F abv normal with widespread
low cloud cover. Maxes Sat will be right arnd normal and with high
sfc td/s it will feel rather muggy once again.

&&

.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY/...
As of 225 PM EDT Friday: Subtropical anticyclone remains anchored
off the Southeast Atlantic coast throughout the period. Another
upper low, although weaker and not well defined, will move out of
the Gulf of Mexico into the Gulf coast states by Monday. These
features keep a moist south to southwest low level flow across the
area each day. The good news is the deep tropical moisture fetch
will not return during this period. However, instability will
increase each day, along with decent upper divergence, keeping the
threat of mainly diurnal convection in place. Greatest coverage
continues to be across the mountains both days with high end
scattered coverage elsewhere. Shear is relatively weak both days,
but surface delta theta-e values increase with steadily drying mid
levels. This leads to an increasing threat of severe thunderstorms
each day, but these should remain isolated as overall DCAPE values
remain on the low side. Heavy rain is possible but the threat is not
as widespread as in previous days. Still, the wet antecedent
conditions could make flooding possible with lower rainfall amounts.
Highs will be nearly steady around 5 degrees above normal. Lows will
be nearly steady as well but around 10 degrees above normal.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
As of 200 PM EDT Friday: Still little airmass change expected as the
medium range begins Monday night. Models are generally plagued by
disagreement in the finer details of the forecast, which
unfortunately make all the difference in a nebulous pattern like the
present one. A Bermuda high will remain off the east coast in the
Atlantic (welcome to summertime), with the southeast on the northern
periphery of an upper subtropical high. Some type of surface
stationary boundary will likely be laid over the Carolinas through
much of the next work week with little progression out of the area
expected. The GFS does spin up an upper/surface low over the
northern Gulf and swing it up towards our area Wednesday, but that
is likely an artifact of a known convective feedback problem in the
GFS (the parallel FV3 core has it too while the low is absent on all
other global models, suggesting this is a GFS model physics issue).
I've therefore favored the ECMWF through much of the medium range.

As far as sensible weather, the Bermuda high will induce weak
southerly flow over the area, though it is not as persistent our
stout as it has been over the past week. PWATs will remain elevated,
but in the absence of much large-scale forcing, a mostly diurnal
pattern favoring afternoon showers and thunderstorms will persist
through next week. Shower and thunderstorm coverage should be
decreased from this week, and chances of any flooding or severe
storms do not stand out any particular day next week at the moment.
The pattern we will enter into next week looks distinctly summer-
ish, as a matter of fact, just with a bit more moisture than usual
to work with. Max temperatures will increase a little to just above
average, with lows remaining about 10 degrees above average.

&&

.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
At KCLT and elsewhere: A mixture of VFR/MVFR will continue across
the area tonight, deteriorating to MVFR/IFR overnight, as showers
and isolated thunderstorms continue to propagate portions of the
area. Between pockets of heavier downpours along with areas of low
cigs and reduced visibilities (heavy rain and/or areas of fog), a
mixture of different flight restrictions is expected. On Saturday,
expect improvement to VFR as another round of VCSH/VCTS is expected
beginning as early as late morning. Southeast winds 5 to 10 kts will
persist.

Outlook: Unsettled weather will continue into the weekend with
isolated to scattered SHRA/TSRA throughout the day/night periods and
deteriorating restrictions at times.

Confidence Table...

            00-06Z        06-12Z        12-18Z        18-00Z
KCLT       High  83%     High  91%     High  91%     High  94%
KGSP       High  88%     High  83%     High  81%     High  95%
KAVL       Med   76%     High  85%     High  89%     High 100%
KHKY       Med   75%     High  92%     Med   77%     High  95%
KGMU       High  91%     High  88%     High  85%     High  96%
KAND       High  88%     High  85%     High  93%     High  98%

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...None.
NC...None.
SC...None.

&&

SYNOPSIS...Carroll
NEAR TERM...SBK/SGL
SHORT TERM...RWH
LONG TERM...Carroll
AVIATION...SGL
Hazardous weather outlook, May 18, 8:18 PM EDT, 2 hours 7 minutes before
Hazardous Weather Outlook
National Weather Service Greenville-Spartanburg SC
818 PM EDT Fri May 18 2018

GAZ010-017-018-026-028-029-NCZ035>037-048-051-052-056>059-062-063-
068>072-082-502-504-506-508-510-SCZ001-004>014-019-200030-
Rabun-Habersham-Stephens-Franklin-Hart-Elbert-Alexander-Iredell-
Davie-Madison-Swain-Haywood-Catawba-Rowan-Graham-Northern Jackson-
Macon-Southern Jackson-Cleveland-Lincoln-Gaston-Mecklenburg-Cabarrus-
Union-Greater Caldwell-Greater Burke-Eastern McDowell-
Greater Rutherford-Eastern Polk-Oconee Mountains-Greater Oconee-
Greater Pickens-Greater Greenville-Spartanburg-Cherokee-York-
Anderson-Abbeville-Laurens-Chester-Greenwood-
818 PM EDT Fri May 18 2018

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

.DAY ONE...Tonight.

Isolated to scattered showers and thunderstorms will continue to move
across the area through tonight. Slow-moving and training storms may
produce torrential downpours over a short period of time, resulting
in localized flash flooding. In addition to the heavy rain potential,
cloud-to-ground lightning and brief gusty winds will be possible
within any stronger storms. Gusty winds could blow down a few trees
due to saturated soils.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday.

..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.
..Wednesday...No hazardous weather is expected at this time.
..Thursday...No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

None.

NCZ033-049-050-053-064-065-501-503-505-507-509-SCZ002-003-200030-
Avery-Yancey-Mitchell-Buncombe-Transylvania-Henderson-
Caldwell Mountains-Burke Mountains-McDowell Mountains-
Rutherford Mountains-Polk Mountains-Pickens Mountains-
Greenville Mountains-
818 PM EDT Fri May 18 2018

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

This Hazardous Weather Outlook is for 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.

   Flash Flood Watch.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday.

..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.
..Wednesday...No hazardous weather is expected at this time.
..Thursday...No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

None.

SGL

In the hours before

Local storm report, May 18, 9:21 PM EDT, 1 hour 4 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
921 PM EDT FRI MAY 18 2018

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

0850 PM     DEBRIS FLOW      3 ESE SALUDA            35.22N 82.30W
05/18/2018                   POLK               NC   COUNTY OFFICIAL

            COUNTY OFFICIALS SAY MUDSLIDES IN THE SALUDA GRADE AREA
            BETWEEN SALUDA AND TRYON.

0900 PM     FLASH FLOOD      1 E SALUDA              35.24N 82.33W
05/18/2018                   POLK               NC   BROADCAST MEDIA

            REPORTS OF SWIFT WATER RESCUES AND PARTS OF INTERSTATE 26
            FLOODED IN THIS AREA.

&&

OUTLAW
Local storm report, May 18, 9:32 PM EDT, 53 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
932 PM EDT FRI MAY 18 2018

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

0855 PM     DEBRIS FLOW      4 ENE GRANDFATHER MOUNT 36.12N 81.78W
05/18/2018                   WATAUGA            NC   AMATEUR RADIO

            REPORTS OF MUDSLIDES AND ROCK SLIDES OCCURRING BETWEEN
            GRANDFATHER MOUNTAIN AND BLOWING ROCK ALONG AND NEAR
            HIGHWAY 221. HAM RADIO OPERATOR REPORTED 10.20 INCHES OF
            RAIN IN THE PAST 24 HOURS. HIS ELEVATION 4105 FEET.

&&

OUTLAW
Local storm report, May 18, 9:50 PM EDT, 35 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
950 PM EDT FRI MAY 18 2018

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

0915 PM     FLASH FLOOD      5 N COLUMBUS            35.32N 82.20W
05/18/2018                   POLK               NC   BROADCAST MEDIA

            REPORT OF LAKE ADGER PKWY BLOCKED DUE TO WATER
            APPROXIMATELY 18 INCHES DEEP FLOWING ACROSS ROADWAY.

&&

LACORTE
Local storm report, May 18, 10:08 PM EDT, 17 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1008 PM EDT FRI MAY 18 2018

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

0950 PM     FLASH FLOOD      1 ENE SALUDA            35.25N 82.33W
05/18/2018                   POLK               NC   PUBLIC

            PUBLIC REPORT THAT EXIT 59 OFF OF INTERSTATE 26 IS
            FLOODED.

&&

OUTLAW
Local storm report, May 18, 10:19 PM EDT, 6 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1019 PM EDT FRI MAY 18 2018

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

1015 PM     FLASH FLOOD      1 SE BANNER ELK         36.15N 81.86W
05/18/2018                   AVERY              NC   PUBLIC

            REPORT OF ROAD WASHED AWAY NEAR THE INTERSECTION OF
            DOBBINS RD AND HANGING ROCK ESTATES LN.

&&

LACORTE
Local storm report, May 18, 10:23 PM EDT, 2 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1023 PM EDT FRI MAY 18 2018

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

0950 PM     HEAVY RAIN       1 N SALUDA              35.25N 82.35W
05/18/2018  M2.62 INCH       POLK               NC   COCORAHS

            2.62 INCHES IN THE PAST 3 HOURS. NEAR THE TOP OF A RIDGE.

&&

OUTLAW

The office that day

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

IssuedProductOfficeCountiesLasted
May 18, 8:20 PM EDTAreal Flood WarningGSPBurke, McDowell3 hr
May 18, 9:56 PM EDTFlash Flood WarningGSPBuncombe, Henderson, Polk, Rutherford4 hr
May 18, 11:01 PM EDTAreal Flood AdvisoryGSPBuncombe, Henderson8 hr
May 18, 11:12 PM EDTFlash Flood WarningGSPBurke, McDowell5 hr
May 18, 11:24 PM EDTAreal Flood WarningGSPRutherford3 hr
May 18, 11:32 PM EDTAreal Flood AdvisoryGSPAvery, Buncombe, Madison, Mitchell, Yancey4 hr
May 19, 12:24 AM EDTFlash Flood WarningGSPCaldwell2 hr
May 19, 1:46 AM EDTAreal Flood WarningGSPBuncombe, Henderson, Polk, Rutherford6 hr
May 19, 2:15 AM EDTAreal Flood WarningGSPAvery, Caldwell18 hr
May 19, 4:20 AM EDTAreal Flood WarningGSPBurke, McDowell20 hr
May 19, 8:18 AM EDTAreal Flood WarningGSPBuncombe, Henderson, Polk, Rutherford12 hr
May 19, 8:40 AM EDTAreal Flood AdvisoryGSPAlexander, Burke, Caldwell, Catawba, McDowell12 hr
May 19, 9:43 AM EDTAreal Flood AdvisoryGSPTransylvania2 hr
May 19, 12:11 PM EDTAreal Flood AdvisoryGSPTransylvania6 hr
May 19, 2:45 PM EDTRiver Flood AdvisoryGSPBuncombe21 hr
May 19, 3:45 PM EDTAreal Flood AdvisoryGSPMadison2 hr
May 19, 3:51 PM EDTSpecial Weather StatementGSPMadison24 min
May 19, 4:11 PM EDTSpecial Weather StatementGSPYancey34 min
May 19, 7:55 PM EDTAreal Flood WarningGSPPolk, Rutherford2 hr

Nearby

Flash Flood Warnings in North Carolina, 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.