Alert archive / North Carolina / Special Weather Statements in 2021

Special Weather Statement, NWS Greenville-Spartanburg, SC

August 4, 2021Graham County, North Carolina

NWS Greenville-Spartanburg, SC issued this special weather statement at Aug 4, 2021, 3:13 PM EDT for Graham County, North Carolina. It was in force for 47 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Aug 4, 2021, 3:13 PM EDT (19:13 UTC)
Expired
Aug 4, 2021, 4:00 PM EDT
In force
47 min
Issued by
NWS Greenville-Spartanburg, SC

County Graham County, NC

The radar

The Knoxville radar (KMRX), 86 km from the middle of the area, began a volume at 19:13 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.

The nearest sounding before it

Peachtre/Fal Fld, GA (KFFC), launched 12:00Z, 7.2 hours before the alert went out and 243 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, Peachtre/Fal Fld, GA at 12:00Z on 2021-08-04Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 258 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Peachtre/Fal Fld, GA at 12:00Z on 2021-08-04The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 0 square meters per square second.19395878Sfc1 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
258 J/kg
Mixed-layer CIN
-10 J/kg
Mixed-layer LCL
590 m above ground
0-6 km bulk shear
28 kt
0-1 km storm-relative helicity
0 m²/s²
0-3 km storm-relative helicity
29 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

402 
WWUS82 KGSP 041913
SPSGSP

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
313 PM EDT Wed Aug 4 2021
 
NCZ051-042000-
Swain NC-
313 PM EDT Wed Aug 4 2021

...HEAVY RAIN SHOWERS WILL IMPACT WEST CENTRAL SWAIN COUNTY UNTIL 
400 PM EDT...

At 311 PM EDT, Doppler radar was tracking a series of heavy rain 
showers affecting the area about 12 miles north of Robbinsville, or 
near Smoky Mountains-Twentymile Creek. These showers were nearly 
stationary, or redeveloping in place.

Locations to be impacted include...
Smoky Mountains-Twentymile Creek, Fontana Village, Smoky Mountains-
Fontana Area, Fontana Lake, Deals Gap and Tapoco. Stream levels will 
rise rapidly along Round Mountain Branch and Twentymile Creek.

Very heavy rainfall rates up to one inch per hour will be possible 
in these areas. Deep ponding of water will develop in low-lying 
areas.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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 3548 8391 3552 8388 3553 8382 3556 8377
      3556 8372 3552 8369 3545 8379 3545 8380
      3544 8381 3545 8385 3545 8386 3546 8387
      3547 8390 3545 8393 3546 8395
TIME...MOT...LOC 1911Z 106DEG 1KT 3550 8381 

$$

HG

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 4, 5:26 PM EDTSpecial Weather StatementGSPRabun49 min
Aug 4, 6:24 PM EDTSpecial Weather StatementGSPHabersham36 min

Nearby

Special Weather Statements in North Carolina, 2021Every special weather statement in 2021

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.