Alert archive / Tennessee / Flash Flood Warnings in 2021

Flash Flood Warning 61, NWS Nashville, TN

September 18, 2021Giles County, Tennessee

NWS Nashville, TN issued this flash flood warning at Sep 18, 2021, 5:21 PM CDT for Giles County, Tennessee. It was in force for 114 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: Sep 18, 2021, 5:21 PM CDT (22:21 UTC)
Expired: Sep 18, 2021, 7:15 PM CDT
In force: 114 min
Issued by: NWS Nashville, TN
Area: Storm-based polygon
Flood severity: None

County Giles County, TN

The radar

The Northeast Alabama radar (KHTX), 87 km from the middle of the area, began a volume at 22:23 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

Nashville Metro, TN (KBNA), launched 12:00Z, 10.4 hours before the alert went out and 126 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: 1085 J/kg
Mixed-layer CIN: -15 J/kg
Mixed-layer LCL: 648 m above ground
0-6 km bulk shear: 7 kt
0-1 km storm-relative helicity: 15 m²/s²
0-3 km storm-relative helicity: 51 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

129 
WGUS54 KOHX 182221
FFWOHX
TNC055-190015-
/O.NEW.KOHX.FF.W.0061.210918T2221Z-210919T0015Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Nashville TN
521 PM CDT Sat Sep 18 2021

The National Weather Service in Nashville has issued a

* Flash Flood Warning for...
  Southeastern Giles County in middle Tennessee...

* Until 715 PM CDT.

* At 521 PM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 2 and 3 inches of rain 
  have fallen. Flash flooding is ongoing or expected to begin 
  shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar.

  IMPACT...Flash flooding of small creeks and streams, urban
           areas, highways, streets and underpasses as well as
           other poor drainage and low-lying areas.

* Some locations that will experience flash flooding include...
  Ardmore, Elkton and Prospect.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3500 8716 3509 8713 3509 8706 3509 8698
      3509 8683 3499 8684

FLASH FLOOD...RADAR INDICATED

$$

Whitehead

The office that day

Everything else NWS Nashville, TN issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Sep 17, 7:04 PM CDT	Areal Flood Advisory	OHX	Perry, Wayne	2 hr
Sep 17, 8:32 PM CDT	Areal Flood Advisory	OHX	Hickman	58 min
Sep 18, 2:24 AM CDT	Flash Flood Watch	OHX	Bedford, Cannon, Cheatham, Clay, Coffee, Cumberland and 32 more	65 hr
Sep 18, 9:54 AM CDT	Areal Flood Advisory	OHX	Cheatham, Davidson, Dickson, Houston, Humphreys, Stewart and 1 more	3 hr
Sep 18, 10:28 AM CDT	Areal Flood Advisory	OHX	Davidson, Rutherford, Sumner, Williamson, Wilson	3 hr
Sep 18, 10:49 AM CDT	Areal Flood Advisory	OHX	Jackson, Smith, Trousdale, Wilson	3 hr
Sep 18, 11:21 AM CDT	Areal Flood Advisory	OHX	Jackson, Overton, Putnam	3 hr
Sep 18, 1:29 PM CDT	Areal Flood Advisory	OHX	Bedford, Coffee	3 hr
Sep 18, 3:25 PM CDT	Flash Flood Warning	OHX	Bedford, Coffee	4 hr
Sep 18, 4:15 PM CDT	Areal Flood Advisory	OHX	Giles	2 hr
Sep 18, 4:32 PM CDT	River Flood Advisory	OHX	Bedford	4 hr

Nearby

Flash Flood Warnings in Tennessee, 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.