Alert archive / North Carolina / Flash Flood Watches in 2018

Flash Flood Watch 5, NWS Greenville-Spartanburg, SC

May 27, 201828 counties in North Carolina; 8 counties in South Carolina; 6 counties in Georgia

NWS Greenville-Spartanburg, SC issued this flash flood watch at May 27, 2018, 4:44 AM EDT for 28 counties in North Carolina; 8 counties in South Carolina; 6 counties in Georgia. It took effect at May 27, 2018, 8:00 PM EDT. It was in force for 4 days.

The area

The counties it named.

The facts

Issued: May 27, 2018, 4:44 AM EDT (08:44 UTC)
In effect from: May 27, 2018, 8:00 PM EDT
Expired: Jun 1, 2018, 2:00 AM EDT
In force: 4 days
Issued by: NWS Greenville-Spartanburg, SC
Flood severity: None

All 42 counties

Elbert County, GA, Franklin County, GA, Habersham County, GA, Hart County, GA, Rabun County, GA, Stephens County, GA, Alexander County, NC, Avery County, NC, Buncombe County, NC, Burke County, NC, Cabarrus County, NC, Caldwell County, NC, Catawba County, NC, Cleveland County, NC, Davie County, NC, Gaston County, NC, Graham County, NC, Haywood County, NC, Henderson County, NC, Iredell County, NC, Jackson County, NC, Lincoln County, NC, Macon County, NC, Madison County, NC, McDowell County, NC, Mecklenburg County, NC, Mitchell County, NC, Polk County, NC, Rowan County, NC, Rutherford County, NC, Swain County, NC, Transylvania County, NC, Union County, NC, Yancey County, NC, Abbeville County, SC, Anderson County, SC, Cherokee County, SC, Chester County, SC, Greenwood County, SC, Laurens County, SC, Union County, SC, York County, SC

The radar

The Greer radar (KGSP), 40 km from the middle of the area, began a volume at 08:43 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 00:00Z, 8.7 hours before the alert went out and 303 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 1377 J/kg
Mixed-layer CIN: -9 J/kg
Mixed-layer LCL: 933 m above ground
0-6 km bulk shear: 6 kt
0-1 km storm-relative helicity: -20 m²/s²
0-3 km storm-relative helicity: 25 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this flash flood watch 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 watch went out at May 27, 4:05 AM EDT, 39 minutes earlier.

Area forecast discussion, May 27, 4:05 AM EDT, 39 minutes before

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Hazardous weather outlook, May 27, 2:20 AM EDT, 2 hours 24 minutes before

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In the hours before

Local storm report, May 27, 12:10 AM EDT, 4 hours 34 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1210 AM EDT SUN MAY 27 2018

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

0825 PM     FLASH FLOOD      BRYSON CITY             35.43N 83.45W
05/26/2018                   SWAIN              NC   EMERGENCY MNGR

            ONE HOME WITH INTERNAL FLOOD DAMAGE. ONE STATE ROAD
            DAMAGED. SEVERAL CITY STREETS WITH MINOR DAMAGE.

&&

RWH

The office that day

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

Issued	Product	Office	Counties	Lasted
May 26, 8:22 PM EDT	Areal Flood Advisory	GSP	Jackson, Macon	113 min
May 26, 9:35 PM EDT	Areal Flood Advisory	GSP	Macon	115 min
May 26, 10:06 PM EDT	Flash Flood Warning	GSP	Macon	3 hr
May 26, 11:21 PM EDT	River Flood Advisory	GSP	Henderson, Transylvania	21 hr
May 26, 11:21 PM EDT	River Flood Advisory	GSP	Buncombe, Henderson	21 hr
May 27, 12:52 AM EDT	Flash Flood Warning	GSP	Macon	82 min
May 27, 10:09 AM EDT	River Flood Warning	GSP	Henderson, Transylvania	8 days
May 27, 6:58 PM EDT	Special Weather Statement	GSP	Avery, Caldwell, McDowell, Mitchell, Yancey	32 min
May 27, 7:12 PM EDT	Special Weather Statement	GSP	Madison	33 min

Nearby

Flash Flood Watches in North Carolina, 2018 Flash Flood Watches in South Carolina, 2018 Flash Flood Watches in Georgia, 2018 Every flash flood watch 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.