Alert archive / North Carolina / Flash Flood Watches in 2018

Flash Flood Watch 2, NWS Greenville-Spartanburg, SC

April 15, 201821 counties in North Carolina; Cherokee County, York County, South Carolina; Rabun County, Georgia

NWS Greenville-Spartanburg, SC issued this flash flood watch at Apr 15, 2018, 3:43 AM EDT for 21 counties in North Carolina; Cherokee County, York County, South Carolina; Rabun County, Georgia. It took effect at Apr 15, 2018, 8:00 AM EDT. It was in force for 12 hr.

The area

The counties it named.

The facts

Issued: Apr 15, 2018, 3:43 AM EDT (07:43 UTC)
In effect from: Apr 15, 2018, 8:00 AM EDT
Expired: Apr 15, 2018, 8:00 PM EDT
In force: 12 hr
Issued by: NWS Greenville-Spartanburg, SC
Flood severity: None

All 24 counties

Rabun County, GA, Alexander County, NC, Avery County, NC, Burke County, NC, Cabarrus County, NC, Caldwell County, NC, Catawba County, NC, Cleveland County, NC, Davie County, NC, Gaston County, NC, Henderson County, NC, Iredell County, NC, Jackson County, NC, Lincoln County, NC, Macon County, NC, McDowell County, NC, Mecklenburg County, NC, Polk County, NC, Rowan County, NC, Rutherford County, NC, Transylvania County, NC, Union County, NC, Cherokee County, SC, York County, SC

The radar

The Greer radar (KGSP), 81 km from the middle of the area, began a volume at 07:44 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

Charleston AFB, SC (KCHS), launched 00:00Z, 7.7 hours before the alert went out and 321 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: 55 J/kg
Mixed-layer CIN: -99 J/kg
Mixed-layer LCL: 625 m above ground
0-6 km bulk shear: 26 kt
0-1 km storm-relative helicity: 136 m²/s²
0-3 km storm-relative helicity: 134 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.1

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 Apr 15, 3:34 AM EDT, 9 minutes earlier.

Area forecast discussion, Apr 15, 3:34 AM EDT, 9 minutes before

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Hazardous weather outlook, Apr 14, 7:36 PM EDT, 8 hours 7 minutes before

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The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 15, 3:38 AM EDT	Freeze Watch	GSP	Buncombe, Graham, Haywood, Jackson, Macon, Madison and 1 more	11 hr
Apr 15, 10:30 AM EDT	Special Weather Statement	GSP	Henderson	60 min
Apr 15, 10:31 AM EDT	Special Weather Statement	GSP	Polk, Rutherford	44 min
Apr 15, 10:39 AM EDT	Special Weather Statement	GSP	McDowell	36 min
Apr 15, 11:25 AM EDT	Special Weather Statement	GSP	McDowell, Rutherford	35 min
Apr 15, 12:00 PM EDT	Severe Thunderstorm Warning	GSP	Avery, Burke, Caldwell, McDowell	45 min
Apr 15, 12:20 PM EDT	Special Weather Statement	GSP	Burke	25 min
Apr 15, 12:29 PM EDT	Severe Thunderstorm Warning	GSP	Cleveland, Rutherford	46 min
Apr 15, 12:44 PM EDT	Flash Flood Warning	GSP	Burke, Caldwell, Cleveland, Polk, Rutherford	4 hr
Apr 15, 12:47 PM EDT	Severe Thunderstorm Warning	GSP	Burke, Catawba, Cleveland, Lincoln, Rutherford	28 min
Apr 15, 1:13 PM EDT	Severe Thunderstorm Warning	GSP	Alexander, Burke, Caldwell, Catawba, Cleveland, Lincoln	32 min
Apr 15, 1:38 PM EDT	Special Weather Statement	GSP	Cleveland	37 min
Apr 15, 1:48 PM EDT	Special Weather Statement	GSP	Cleveland, Lincoln	27 min
Apr 15, 1:50 PM EDT	Special Weather Statement	GSP	Alexander, Catawba	25 min
Apr 15, 2:14 PM EDT	Special Weather Statement	GSP	Alexander, Catawba, Cleveland, Gaston, Iredell, Lincoln	31 min
Apr 15, 2:44 PM EDT	Severe Thunderstorm Warning	GSP	Gaston, Mecklenburg	46 min
Apr 15, 2:47 PM EDT	Special Weather Statement	GSP	Alexander	28 min
Apr 15, 2:58 PM EDT	Freeze Warning	GSP	Graham, Haywood, Jackson, Macon, Swain	42 hr
Apr 15, 3:02 PM EDT	Tornado Warning	GSP	Gaston, Mecklenburg	28 min
Apr 15, 3:15 PM EDT	Severe Thunderstorm Warning	GSP	Mecklenburg, Union	30 min
Apr 15, 3:25 PM EDT	Severe Thunderstorm Warning	GSP	Cabarrus, Catawba, Gaston, Iredell, Lincoln, Mecklenburg and 1 more	37 min
Apr 15, 3:41 PM EDT	Severe Thunderstorm Warning	GSP	Cabarrus, Mecklenburg, Rowan, Union	34 min
Apr 15, 3:55 PM EDT	Severe Thunderstorm Warning	GSP	Davie, Iredell, Rowan	35 min
Apr 15, 4:14 PM EDT	Severe Thunderstorm Warning	GSP	Cabarrus, Rowan	31 min
Apr 15, 5:34 PM EDT	Areal Flood Warning	GSP	Avery, Burke, Caldwell, McDowell, Mitchell, Yancey	6 hr
Apr 15, 7:52 PM EDT	Areal Flood Advisory	GSP	Cleveland, Polk, Rutherford	113 min
Apr 15, 11:21 AM EDT	Special Weather Statement	GSP	Greenwood, Laurens	39 min
Apr 15, 11:45 AM EDT	Special Weather Statement	GSP	Cherokee, Spartanburg	45 min
Apr 15, 11:50 AM EDT	Severe Thunderstorm Warning	GSP	Greenville, Laurens, Spartanburg	25 min
Apr 15, 12:13 PM EDT	Severe Thunderstorm Warning	GSP	Greenwood, Laurens	47 min
Apr 15, 12:19 PM EDT	Severe Thunderstorm Warning	GSP	Laurens, Spartanburg	41 min
Apr 15, 12:31 PM EDT	Flash Flood Warning	GSP	Cherokee, Greenwood, Laurens, Spartanburg	3 hr
Apr 15, 12:38 PM EDT	Severe Thunderstorm Warning	GSP	Laurens, Spartanburg, Union	52 min
Apr 15, 1:17 PM EDT	Severe Thunderstorm Warning	GSP	Cherokee, Spartanburg, Union	43 min
Apr 15, 2:09 PM EDT	Special Weather Statement	GSP	Cherokee, Union	36 min
Apr 15, 2:29 PM EDT	Severe Thunderstorm Warning	GSP	Cherokee, Chester, Union, York	46 min
Apr 15, 6:57 PM EDT	Areal Flood Advisory	GSP	Cherokee, Greenwood, Laurens, Spartanburg, Union	2 hr

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.