Alert archive / North Carolina / Flash Flood Warnings in 2021

Flash Flood Warning 7, NWS Raleigh, NC

July 1, 2021Forsyth County, Guilford County, North Carolina

NWS Raleigh, NC issued this flash flood warning at Jul 1, 2021, 11:00 PM EDT for Forsyth County, Guilford County, North Carolina. It was in force for 3 hr. 1 report 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 1, 2021, 11:00 PM EDT (03:00 UTC)
Expired: Jul 2, 2021, 2:00 AM EDT
In force: 3 hr
Issued by: NWS Raleigh, NC
Area: Storm-based polygon
Damage threat: Considerable
Flood severity: None

Counties Forsyth County, NC, Guilford County, NC

The radar

The Roanoke radar (KFCX), 103 km from the middle of the area, began a volume at 03:01 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

Time	Report	Where	Remark
Jul 2, 12:45 AM EDT	FLASH FLOOD	2 Ssw Winston-Salem, NC	HAWTHORNE AND MILLER STREETS FLOODED IN WINSTON SALEM.

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

The nearest sounding before it

Greensboro/Hi Pt, NC (KGSO), launched 00:00Z, 3.0 hours before the alert went out and 43 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: 541 J/kg
Mixed-layer CIN: -12 J/kg
Mixed-layer LCL: 1416 m above ground
0-6 km bulk shear: 14 kt
0-1 km storm-relative helicity: 62 m²/s²
0-3 km storm-relative helicity: 122 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

019 
WGUS52 KRAH 020300
FFWRAH
NCC067-081-020600-
/O.NEW.KRAH.FF.W.0007.210702T0300Z-210702T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Raleigh NC
1100 PM EDT Thu Jul 1 2021

The National Weather Service in Raleigh has issued a

* Flash Flood Warning for...
  Forsyth County in central North Carolina...
  Northwestern Guilford County in central North Carolina...

* Until 200 AM EDT.

* At 1100 PM EDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Around 1 inch of rain has 
  fallen since 1015 PM. Additional rainfall amounts of 1 to 2 inches 
  are possible in the warned area. Flash flooding is ongoing or 
  expected to begin shortly.

  HAZARD...Life threatening flash flooding. Thunderstorms
           producing flash flooding.

  SOURCE...Radar.

  IMPACT...Life threatening flash flooding of creeks and streams,
           urban areas, highways, streets and underpasses.

* Some locations that will experience flash flooding include...
  Winston-Salem, Kernersville, Clemmons, Huntsville, Lewisville, 
  Summerfield, Stokesdale, Walkertown, Rural Hall, Stanleyville, 
  Pfafftown, Sedge Garden, Belews Creek, Colfax, Belews Lake and 
  Donnaha.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

&&

LAT...LON 3624 8045 3626 8041 3625 7980 3612 8001
      3603 8012 3602 8027 3597 8040 3599 8042
      3600 8041 3602 8042 3603 8044 3606 8046
      3604 8049 3605 8051 3608 8052 3611 8051
      3612 8046 3614 8044 3621 8045 3622 8043

FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE

$$

GIH

1 follow-up statement

435 
WGUS72 KRAH 020407
FFSRAH

Flash Flood Statement
National Weather Service Raleigh NC
1207 AM EDT Fri Jul 2 2021

NCC067-081-020600-
/O.CON.KRAH.FF.W.0007.000000T0000Z-210702T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Forsyth NC-Guilford NC-
1207 AM EDT Fri Jul 2 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 2 AM EDT EARLY THIS 
MORNING FOR FORSYTH AND NORTHWESTERN GUILFORD COUNTIES...

At 1207 AM EDT, Doppler radar indicated thunderstorms producing 
heavy rain across the warned area. Between 1 and 2 inches of rain 
have fallen in the last hour and a half. Additional rainfall amounts 
of 1 to 2 inches are possible in the warned area. Flash flooding is 
ongoing or expected to begin shortly.

HAZARD...Life threatening flash flooding. Thunderstorms producing
         flash flooding.

SOURCE...Radar.

IMPACT...Life threatening flash flooding of creeks and streams,
         urban areas, highways, streets and underpasses.

Some locations that will experience flash flooding include...
  Winston-Salem, Kernersville, Clemmons, Huntsville, Lewisville, 
  Summerfield, Stokesdale, Walkertown, Rural Hall, Stanleyville, 
  Pfafftown, Sedge Garden, Belews Creek, Colfax, Belews Lake and 
  Donnaha. This also includes Salem CreeK, Lowery Mill Creek, and 
  Brushy Fork.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

&&

LAT...LON 3624 8045 3626 8041 3625 7980 3612 8001
      3603 8012 3602 8027 3597 8040 3599 8042
      3600 8041 3602 8042 3603 8044 3606 8046
      3604 8049 3605 8051 3608 8052 3611 8051
      3612 8046 3614 8044 3621 8045 3622 8043

FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE

$$

GIH

The office that day

Everything else NWS Raleigh, NC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 1, 8:24 PM EDT	Special Weather Statement	RAH	Moore, Scotland	51 min
Jul 1, 8:40 PM EDT	Severe Thunderstorm Warning	RAH	Harnett, Hoke, Lee, Moore, Richmond, Scotland	50 min
Jul 1, 9:09 PM EDT	Severe Thunderstorm Warning	RAH	Cumberland, Harnett, Hoke, Lee, Moore, Wake	51 min
Jul 1, 9:26 PM EDT	Special Weather Statement	RAH	Davidson	34 min
Jul 1, 9:38 PM EDT	Severe Thunderstorm Warning	RAH	Chatham, Cumberland, Durham, Harnett, Johnston, Lee and 2 more	52 min
Jul 1, 10:01 PM EDT	Severe Thunderstorm Warning	RAH	Durham, Franklin, Granville, Vance, Wake	44 min
Jul 1, 10:33 PM EDT	Special Weather Statement	RAH	Guilford	42 min
Jul 1, 10:35 PM EDT	Special Weather Statement	RAH	Cumberland, Johnston, Sampson, Wayne, Wilson	55 min
Jul 1, 10:42 PM EDT	Severe Thunderstorm Warning	RAH	Franklin, Granville, Vance, Warren	48 min
Jul 2, 9:05 AM EDT	Special Weather Statement	RAH	Wayne	25 min
Jul 2, 9:34 AM EDT	Areal Flood Advisory	RAH	Wilson	116 min
Jul 2, 10:58 AM EDT	Special Weather Statement	RAH	Sampson	32 min

Nearby

Flash Flood Warnings in North Carolina, 2021 Every flash flood warning 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.