Alert archive / North Carolina / Severe Thunderstorm Warnings in 2017

Severe Thunderstorm Warning 220, NWS Greenville-Spartanburg, SC

July 18, 2017Gaston County, Lincoln County, North Carolina

NWS Greenville-Spartanburg, SC issued this severe thunderstorm warning at Jul 18, 2017, 9:09 PM EDT for Gaston County, Lincoln County, North Carolina. It was in force for 51 min. 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
Jul 18, 2017, 9:09 PM EDT (01:09 UTC)
Expired
Jul 18, 2017, 10:00 PM EDT
In force
51 min
Issued by
NWS Greenville-Spartanburg, SC
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Gaston County, NC, Lincoln County, NC

The radar

The Greer radar (KGSP), 111 km from the middle of the area, began a volume at 01:10 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
Jul 18, 9:12 PM EDTTSTM WND DMG2 S Stanley, NC2 TREES DOWN.
Jul 18, 9:13 PM EDTTSTM WND DMG2 W Mount Holly, NCCOUNTY REPORTS TREE BLOWN DOWN. TIME EST FROM RADAR.

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 2 storm reports to this severe thunderstorm warning; the first came 3 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, 1.2 hours before the alert went out and 139 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 2017-07-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 292 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 2017-07-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -16 square meters per square second.1939Sfc1 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
292 J/kg
Mixed-layer CIN
-75 J/kg
Mixed-layer LCL
1806 m above ground
0-6 km bulk shear
6 kt
0-1 km storm-relative helicity
-16 m²/s²
0-3 km storm-relative helicity
-32 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

021 
WUUS52 KGSP 190109
SVRGSP
NCC071-109-190200-
/O.NEW.KGSP.SV.W.0220.170719T0109Z-170719T0200Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Greenville-Spartanburg SC
909 PM EDT TUE JUL 18 2017

The National Weather Service in Greenville-Spartanburg has issued a

* Severe Thunderstorm Warning for...
  Southeastern Lincoln County in the Piedmont of North Carolina...
  Gaston County in the Piedmont of North Carolina...

* Until 1000 PM EDT

* At 908 PM EDT, a severe thunderstorm was located 7 miles northeast
  of Gastonia, or over Stanley, moving southwest at 5 mph.

  HAZARD...60 mph wind gusts and quarter size hail. 

  SOURCE...Radar indicated. 

  IMPACT...Minor hail damage to vehicles is expected. Expect wind 
           damage to trees and power lines. 

* Locations impacted include...
  Gastonia, Mt Holly, Bessemer City, South Gastonia, Dallas, Stanley,
  Cramerton, Lowell, Ranlo and High Shoals.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Scattered trees and power lines will be blown down in the warned
area. Seek shelter inside an interior room.

Please report damaging winds, hail, or flooding to the National
Weather Service Greenville-Spartanburg by calling toll free, 1, 800,
2 6 7, 8 1 0 1, or by posting on our Facebook page, or Tweet it using
hashtag nwsgsp. Your message should describe the event and the
specific location where it occurred.

&&

LAT...LON 3530 8100 3527 8101 3516 8120 3516 8122
      3539 8135 3546 8106 3532 8098
TIME...MOT...LOC 0108Z 063DEG 5KT 3535 8111 

HAIL...1.00IN
WIND...60MPH
 
$$

ARK
1 follow-up statement
986 
WWUS52 KGSP 190151
SVSGSP

Severe Weather Statement
National Weather Service Greenville-Spartanburg SC
951 PM EDT TUE JUL 18 2017

NCC071-109-190201-
/O.EXP.KGSP.SV.W.0220.000000T0000Z-170719T0200Z/
Lincoln NC-Gaston NC-
951 PM EDT TUE JUL 18 2017

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN LINCOLN AND
GASTON COUNTIES WILL EXPIRE AT 1000 PM EDT...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore the warning will be allowed to expire.  However gusty winds
and heavy rain are still possible with this thunderstorm.

If you observed large hail or wind damage, please report it to the
National Weather Service Greenville-Spartanburg by calling toll free,
1, 800, 2 6 7, 8 1 0 1, or by posting on our Facebook page, or Tweet
it using hashtag nwsgsp. Your message should describe the event and
the specific location where it occurred.

LAT...LON 3530 8100 3527 8101 3516 8120 3516 8122
      3539 8135 3546 8106 3532 8098
TIME...MOT...LOC 0151Z 063DEG 5KT 3532 8117 

$$

ARK

What forecasters said that day

The local office's own words before this severe thunderstorm 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 severe thunderstorm warning went out at Jul 18, 7:51 PM EDT, 1 hour 18 minutes earlier.

Area forecast discussion, Jul 18, 7:51 PM EDT, 1 hour 18 minutes before
Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
751 PM EDT Tue Jul 18 2017

.SYNOPSIS...
A stalled frontal boundary will slowly dissipate over the next
few days as a strong upper ridge gradually builds into the region.
This will bring hot temperatures and a reduction in the coverage of
diurnal showers and thunderstorms through the end of the work week.
Temperatures will begin to moderate by the weekend while enhanced
thunderstorm chances return to the forecast early next week.

&&

.NEAR TERM /THROUGH WEDNESDAY/...
As of 730 pm EDT: Scattered thunderstorms continue to develop
along outflow boundaries, mainly in the Srn Piedmont of NC/metro
CLT, the GSP area, and the srn mountains of NC. Expect areas to
the south to have a continued chance for more storms for the next
several hours as the environment still has sbCAPE on the order of
1500-2500 J/kg. Precip prob will be adjusted accordingly. Cannot
rule out a few more severe storms given all the mid-level dry air
seen on water vapor imagery and dCAPE above 800 J/kg across the
aforementioned area.

Otherwise...a closing upper-level low pressure system will
migrate slowly east across the piedmont and coastal plain of
the Carolinas tonight through Wednesday. Meanwhile, heights will
steadily recover from the west. A weak vorticity lobe will cross
the mountains on the back side of the main trough late today and
this feature, along with weak upslope flow, will generate scattered
convection into the mid-evening along and east of the Blue Ridge,
mainly in SC/northeast GA. After the convection wanes, PoPs will
diminish greatly later this evening and overnight, with the main
overnight issue likely being low clouds and fog in the mountain
river valleys. Low clouds east of the mountains should be less
widespread given the slightly drier boundary layer.

On Wednesday, profiles exhibit less instability, lapse rates are
more modest, and triggering should be weaker. Scattered ridge top
coverage still seems likely as sbCAPE rebounds to 1500+ J/kg in
many areas. 850 mb flow will acquire a light downsloping component
to further limit PoPs east of the high terrain. Anticipate max
temps another 2 degrees above current day maxes, with Heat Index
values likely reaching the upper 90s.

&&

.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
As of 230 PM EDT Tuesday:  The short term fcst period kicks off on
Wednesday evening amidst gradually building heights from the west
as a large upper anticyclone strengthens over the plains, while an
H5 depression/low slowly meanders along the Carolina coastline.
At the surface, high pressure anchored over the western Atlantic
will remain dominant, likely suppressing convection to some degree.
With that, the fcst will kick off to feature low end pops,
mainly along the high terrain where inhibition will be weakest.
Said pops will taper into the overnight leading into a dry fcst for
Thursday morning.  By that time the upper ridge will have shifted
over the MidSouth region with enough warming aloft to suppress
convection across much if not all of the fcst area for Thursday
therefore pops will remain below mentionable levels.

Meanwhile, the aforementioned H5 depression is progged to
retrograde westward along the SC/FL coastline, eventually moving
inland by Friday.  This feature looks to complicate fcst somewhat
as it pertains to excessive heat, especially on Friday when the
upper ridge weakens slightly as these two features interact.
As a result, fcst pops will be slightly higher on Friday as deep
subsidence is weaker across the mtns/fthills, however remaining dry
over the piedmont.  As for temperatures and heat indices, expecting
highs in the lower/mid 90s across the low terrain, with upper 80s in
the mtn valleys on Thursday.  Further warming is fcst on Friday when
maxes push into the mid/upper 90s for the low terrain, while lower
90s are favored in the mtn valleys.  Given very moist dewpoints
and minimal mixing, heat index values for Thursday and Friday will
be critical, with values approaching 100 and 105 respectively,
the highest of those indices to be observed along/south of I85.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
As of 230 PM EDT Tuesday: Large shifts in the guidance with this
medium range package. Previous forecasts hinged on the expansion of
a strong upper level ridge into the southeast as an upper level
trough axis shifted eastward into the Atlantic. For the latest
cycles though, all major models are now showing the upper trough
over the east coast pinching off an upper level disturbance that
hangs over the southeast and migrates towards the Gulf coast through
the weekend. This will prevent major height rises over the weekend,
so temperatures were trimmed down a few degrees on Saturday and
Sunday, while pops were raised to come closer to climo. Upper level
troughing will return early next week, and with it more moderate
temperatures and a surface front that will provide a focus for some
enhanced diurnal convection, especially Tuesday afternoon.

&&

.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
At KCLT: main concern initially is the development of thunderstorms
on an outflow boundary over the CLT metro area...with potential
for the boundary to fill in between a storm near KIPJ and another
near KJQF. For that reason, will keep the TEMPO for thunderstorms
in the initial period and re-evaluate shortly. The arrival of the
outflow boundary will probably bring the wind around to N or NE
for the first hour or two. Thereafter, expect wind to go light and
variable and clouds to thin out to debris cirrus. Overnight, the
weak upslope flow of last night is not expected to be significant
and the boundary layer has dried out somewhat, so think we should
be limited to a possible MVFR fog restriction around the start of
morning operations. Any restriction should burn off quickly. The
models are much less keen on developing any storms on Wednesday
afternoon, so the fcst was kept with only scattered high based
stratocu. Wind should come around to light SW in the afternoon.

Elsewhere: a few storms in the vicinity of the Upstate TAF sites to
begin with.  After that, convective debris clouds and wind going
light/variable overnight. No precip to speak of at the TAF sites
so the potential for any thing more than brief MVFR restrictions
is lower than the past few nights. So, the fcst sticks with an
MVFR fog right around daybreak. The mountain valleys will once
again see the best chance of low clouds and fog. Only KAVL gets
a VCTS for Wednesday afternoon as the environment looks much less
conducive to convection outside the mtns. Light winds will remain
mainly southerly, turning more westerly on Wed.

Outlook: Morning fog development can be expected in the
mountain valleys and in areas that receive rainfall the previous
afternoon/evening. Drier air will likely limit convective coverage
for Thursday, with typical mid-summer conditions returning by
Saturday.

Confidence Table...

            00-06Z        06-12Z        12-18Z        18-00Z
KCLT       High 100%     High  91%     High  97%     High 100%
KGSP       High 100%     High  97%     High 100%     High 100%
KAVL       High 100%     High  97%     High  97%     High 100%
KHKY       High 100%     High  97%     High 100%     High 100%
KGMU       High 100%     High  97%     High 100%     High 100%
KAND       High 100%     High  94%     High 100%     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 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...HG/PM
SHORT TERM...CDG
LONG TERM...Carroll
AVIATION...PM
Hazardous weather outlook, Jul 18, 6:51 AM EDT, 14 hours 18 minutes before
Hazardous Weather Outlook
National Weather Service Greenville-Spartanburg SC
651 AM EDT Tue Jul 18 2017

GAZ010-017-018-026-028-029-NCZ033-035>037-048>053-056>059-062>065-
068>072-082-501>510-SCZ001>014-019-191100-
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-
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-Chester-Greenwood-
651 AM EDT Tue Jul 18 2017

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

.DAY ONE...Today and Tonight.

Isolated to scattered thunderstorms are expected to develop again
across the area this afternoon and evening. The main threats will be
from cloud to ground lightning and locally heavy rainfall. However,
a few storms could become briefly severe, with damaging winds being
the primary threat.

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

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

.SPOTTER INFORMATION STATEMENT...

None.

LANE

In the hours before

Special weather statement, Jul 18, 7:52 PM EDT, 1 hour 17 minutes before
Special Weather Statement
National Weather Service Greenville-Spartanburg SC
752 PM EDT TUE JUL 18 2017

NCZ082-190015-
Union NC-
752 PM EDT TUE JUL 18 2017

...A STRONG THUNDERSTORM WILL IMPACT NORTHEASTERN UNION COUNTY UNTIL
815 PM EDT...

At 750 PM EDT, Doppler radar was tracking a strong thunderstorm 14
miles southwest of Albemarle, or 10 miles east of Midland, moving
southwest at 15 mph.

Locations to be impacted include...
Unionville, Marshville, Wingate, Fairview and New Salem.

Wind gusts up to 45 mph and pea size hail will be possible in these
areas.

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.

&&

LAT...LON 3493 8031 3506 8059 3518 8048 3517 8047
      3516 8044 3517 8042 3516 8041 3518 8037
      3517 8036 3518 8031 3519 8030 3519 8028
TIME...MOT...LOC 2350Z 028DEG 13KT 3518 8033

ARK
Local storm report, Jul 18, 8:17 PM EDT, 52 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
817 PM EDT TUE JUL 18 2017

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

0600 PM     HAIL             3 SW HENDERSONVILLE     35.30N 82.50W
07/18/2017  E1.00 INCH       HENDERSON          NC   PUBLIC

            QUARTER SIZE HAIL NEAR CUMMINGS COVE COUNTRY CLUB.

&&

KRENTZ
Special weather statement, Jul 18, 8:27 PM EDT, 42 minutes before
Special Weather Statement
National Weather Service Greenville-Spartanburg SC
827 PM EDT TUE JUL 18 2017

NCZ071-190100-
Mecklenburg NC-
827 PM EDT TUE JUL 18 2017

...A STRONG THUNDERSTORM WILL IMPACT CENTRAL MECKLENBURG COUNTY UNTIL
900 PM EDT...

At 827 PM EDT, Doppler radar was tracking a strong thunderstorm near
Uptown Charlotte, or near The Plaza, moving southwest at 5 mph.

Locations to be impacted include...
Uptown Charlotte, Central Charlotte, South Charlotte, Southwest
Charlotte, East Charlotte, Northwest Charlotte, Freedom Park, Reedy
Creek Park, The Plaza and Charlotte Douglas Airport.

Wind gusts up to 50 mph and dime size hail will be possible in these
areas.

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.

Dime to nickel size hail can cause considerable damage to vehicles.
Consider moving vehicles to a covered storage area before the storm
arrives.

&&

LAT...LON 3506 8074 3505 8075 3518 8100 3520 8101
      3521 8100 3535 8084 3525 8066
TIME...MOT...LOC 0027Z 031DEG 4KT 3524 8080

ARK
Special weather statement, Jul 18, 8:50 PM EDT, 19 minutes before
Special Weather Statement
National Weather Service Greenville-Spartanburg SC
850 PM EDT TUE JUL 18 2017

SCZ006-010-011-190115-
Anderson SC-Abbeville SC-Greater Greenville SC-
850 PM EDT TUE JUL 18 2017

...A STRONG THUNDERSTORM WILL IMPACT SOUTHEASTERN GREENVILLE...
NORTHEASTERN ANDERSON AND NORTHEASTERN ABBEVILLE COUNTIES UNTIL 915
PM EDT...

At 850 PM EDT, Doppler radar was tracking a strong thunderstorm 12
miles east of Anderson, or 4 miles northeast of Belton, moving south
at 15 mph.

Locations to be impacted include...
Belton, Williamston, Honea Path, West Pelzer, Fork Shoals and
Princeton.

Wind gusts up to 45 mph and pea size hail will be possible in these
areas.

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.

&&

LAT...LON 3442 8258 3468 8251 3467 8229 3451 8227
      3449 8230 3448 8231 3447 8231 3445 8228
      3443 8228 3443 8226 3440 8226
TIME...MOT...LOC 0050Z 003DEG 11KT 3455 8242

ARK
Local storm report, Jul 18, 8:55 PM EDT, 14 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
855 PM EDT TUE JUL 18 2017

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

0844 PM     HAIL             3 NW CHARLOTTE          35.23N 80.87W
07/18/2017  E1.00 INCH       MECKLENBURG        NC   PUBLIC

            QUARTER SIZE HAIL REPORTED IN THE WESLEY HEIGHTS
            NEIGHBORHOOD.

&&

KRENTZ
Special weather statement, Jul 18, 8:55 PM EDT, 14 minutes before
Special Weather Statement
National Weather Service Greenville-Spartanburg SC
855 PM EDT TUE JUL 18 2017

NCZ082-190130-
Union NC-
855 PM EDT TUE JUL 18 2017

...A STRONG THUNDERSTORM WILL IMPACT SOUTH CENTRAL UNION COUNTY UNTIL
930 PM EDT...

At 855 PM EDT, Doppler radar was tracking a strong thunderstorm 8
miles south of Monroe, or 6 miles southeast of Mineral Springs,
moving south at 15 mph.

Locations to be impacted include...
Mineral Springs and Trinity.

Wind gusts up to 40 mph and pea size hail will be possible in these
areas.

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.

&&

LAT...LON 3482 8071 3496 8067 3495 8045 3481 8043
TIME...MOT...LOC 0055Z 003DEG 11KT 3487 8060

ARK

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 18, 8:07 PM EDTSevere Thunderstorm WarningGSPCabarrus, Mecklenburg, Union38 min
Jul 18, 8:27 PM EDTSpecial Weather StatementGSPMecklenburg33 min
Jul 18, 8:38 PM EDTSevere Thunderstorm WarningGSPGaston, Mecklenburg37 min
Jul 18, 8:55 PM EDTSpecial Weather StatementGSPUnion35 min
Jul 18, 9:23 PM EDTAreal Flood AdvisoryGSPMecklenburg112 min
Jul 18, 9:23 PM EDTSpecial Weather StatementGSPLincoln37 min
Jul 18, 9:58 PM EDTSpecial Weather StatementGSPLincoln32 min
Jul 18, 10:09 PM EDTSpecial Weather StatementGSPCleveland36 min
Jul 18, 10:22 PM EDTSpecial Weather StatementGSPCleveland23 min
Jul 19, 4:05 PM EDTSpecial Weather StatementGSPIredell25 min
Jul 19, 5:50 PM EDTSpecial Weather StatementGSPMecklenburg25 min

Nearby

Severe Thunderstorm Warnings in North Carolina, 2017Every severe thunderstorm warning in 2017

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.