Alert archive / Tennessee / Flash Flood Warnings in 2021

Flash Flood Warning 4, NWS Nashville, TN

February 27, 20214 counties in Tennessee

NWS Nashville, TN issued this flash flood warning at Feb 27, 2021, 10:01 PM CST for 4 counties in Tennessee. It was in force for 119 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: Feb 27, 2021, 10:01 PM CST (04:01 UTC)
Expired: Feb 28, 2021, 12:00 AM CST
In force: 119 min
Issued by: NWS Nashville, TN
Area: Storm-based polygon
Flood severity: None

Counties Davidson County, TN, Sumner County, TN, Trousdale County, TN, Wilson County, TN

The radar

The Nashville radar (KOHX), 8 km from the middle of the area, began a volume at 04:05 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 00:00Z, 4.0 hours before the alert went out and 21 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: 35 J/kg
Mixed-layer CIN: -117 J/kg
Mixed-layer LCL: 527 m above ground
0-6 km bulk shear: 70 kt
0-1 km storm-relative helicity: 189 m²/s²
0-3 km storm-relative helicity: 214 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

420 
WGUS54 KOHX 280401
FFWOHX
TNC037-165-169-189-280600-
/O.NEW.KOHX.FF.W.0004.210228T0401Z-210228T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Nashville TN
1001 PM CST Sat Feb 27 2021

The National Weather Service in Nashville has issued a

* Flash Flood Warning for...
  Central Davidson County in middle Tennessee...
  Southern Sumner County in middle Tennessee...
  Southwestern Trousdale County in middle Tennessee...
  Northwestern Wilson County in middle Tennessee...

* Until midnight CST.

* At 1001 PM CST, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 1 and 2.5 inches of 
  rain have fallen. Flash flooding is ongoing or expected to begin 
  shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Doppler radar.

  IMPACT...Flooding of small creeks and streams, urban areas,
           highways, streets and underpasses as well as other
           drainage and low lying areas.

* Some locations that will experience flash flooding include...
  Gallatin, Lebanon, Nashville, Madison, Hendersonville, Mount 
  Juliet, Goodlettsville, Millersville, Lakewood, Old Hickory, 
  Belinda City, Hermitage, Rural Hill, Green Hill, Percy Priest 
  Lake, Bledsoe Creek State Park, Dickerson Chapel Recreation Area 
  and Whites Creek.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Excessive runoff from heavy rainfall will cause flooding of small 
creeks and streams, urban areas, highways, streets and underpasses 
as well as other drainage areas and low lying spots.

A Flash Flood Warning means that flooding is imminent or occurring. 
If you are in the warned area move to higher ground immediately. 
Residents living along streams and creeks should take immediate 
precautions to protect life and property.

&&

LAT...LON 3634 8672 3652 8635 3636 8628 3629 8614
      3611 8653 3621 8697

FLASH FLOOD...RADAR INDICATED

$$

Barnwell

The office that day

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

Issued	Product	Office	Counties	Lasted
Feb 27, 7:00 PM CST	Special Weather Statement	OHX	Hickman, Perry	45 min
Feb 27, 7:25 PM CST	Areal Flood Advisory	OHX	Hickman, Perry	2 hr
Feb 27, 7:31 PM CST	Areal Flood Advisory	OHX	Cheatham, Davidson, Maury, Rutherford, Williamson	3 hr
Feb 27, 7:52 PM CST	Flash Flood Warning	OHX	Dickson, Hickman, Perry	3 hr
Feb 27, 8:07 PM CST	Flash Flood Warning	OHX	Cheatham, Davidson, Rutherford, Williamson	3 hr
Feb 27, 8:12 PM CST	Special Weather Statement	OHX	Hickman	48 min
Feb 27, 8:16 PM CST	Areal Flood Advisory	OHX	Smith, Trousdale, Wilson	3 hr
Feb 27, 8:40 PM CST	Flash Flood Warning	OHX	Smith, Wilson	3 hr
Feb 27, 8:59 PM CST	Areal Flood Advisory	OHX	Davidson, Sumner, Trousdale, Wilson	3 hr
Feb 27, 9:08 PM CST	Areal Flood Advisory	OHX	Jackson, Smith	112 min
Feb 28, 12:36 AM CST	River Flood Advisory	OHX	Davidson	3 days
Feb 28, 12:47 AM CST	River Flood Advisory	OHX	Hickman	3 hr
Feb 28, 9:43 AM CST	River Flood Advisory	OHX	Davidson	64 hr
Feb 28, 2:44 PM CST	Special Weather Statement	OHX	Macon	31 min
Feb 28, 3:11 PM CST	Special Weather Statement	OHX	Macon	34 min
Feb 28, 5:55 PM CST	Flash Flood Warning	OHX	Houston, Humphreys, Montgomery, Robertson, Stewart	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.