Alert archive / Tennessee / Flash Flood Warnings in 2021

Flash Flood Warning 36, NWS Morristown, TN

August 30, 2021Bradley County, Tennessee

NWS Morristown, TN issued this flash flood warning at Aug 30, 2021, 6:20 PM EDT for Bradley County, Tennessee. It was in force for 115 min. 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
Aug 30, 2021, 6:20 PM EDT (22:20 UTC)
Expired
Aug 30, 2021, 8:15 PM EDT
In force
115 min
Issued by
NWS Morristown, TN
Area
Storm-based polygon
Flood severity
None

County Bradley County, TN

The radar

The Northeast Alabama radar (KHTX), 106 km from the middle of the area, began a volume at 22:21 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

TimeReportWhereRemark
Aug 30, 6:41 PM EDTFLASH FLOOD2 Nnw Waterville, TNSEVERAL ROADWAYS FLOODED.

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

The nearest sounding before it

Nashville Metro, TN (KBNA), launched 12:00Z, 10.3 hours before the alert went out and 188 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-pSkew-T log-p diagram, Nashville Metro, TN at 12:00Z on 2021-08-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 437 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Nashville Metro, TN at 12:00Z on 2021-08-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 32 square meters per square second.1939Sfc1 km3 km6 km9 kmRMLM
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
437 J/kg
Mixed-layer CIN
-81 J/kg
Mixed-layer LCL
1082 m above ground
0-6 km bulk shear
15 kt
0-1 km storm-relative helicity
32 m²/s²
0-3 km storm-relative helicity
17 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

921 
WGUS54 KMRX 302220
FFWMRX
TNC011-310015-
/O.NEW.KMRX.FF.W.0036.210830T2220Z-210831T0015Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Morristown TN
620 PM EDT Mon Aug 30 2021

The National Weather Service in Morristown has issued a

* Flash Flood Warning for...
  Bradley County in east Tennessee...

* Until 815 PM EDT.

* At 620 PM EDT, Doppler radar indicated thunderstorms producing 
  heavy rain in Bradley county. Several reports of roadway flooding. 
  Between 1 and 2.5 inches of rain have fallen. Additional rainfall 
  amounts of 0.5 to 1 inch are possible in the warned area. Flash 
  flooding is already occurring.

  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...
  Cleveland, East Cleveland, South Cleveland, Wildwood Lake, 
  Waterville, Flint Springs, Tasso, McDonald, Hopewell, Gap Springs, 
  Red Clay State Park and Apison.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Be aware of your surroundings and do not drive on flooded roads.

&&

LAT...LON 3529 8494 3518 8470 3509 8475 3508 8474
      3499 8478 3499 8497 3502 8496 3503 8499
      3505 8500 3506 8500 3508 8500 3508 8501
      3510 8501 3513 8503 3514 8503 3515 8502
      3515 8501 3517 8501

FLASH FLOOD...RADAR INDICATED

$$

DH
1 follow-up statement
121 
WGUS74 KMRX 302326
FFSMRX

Flash Flood Statement
National Weather Service Morristown TN
726 PM EDT Mon Aug 30 2021

TNC011-310015-
/O.CON.KMRX.FF.W.0036.000000T0000Z-210831T0015Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Bradley TN-
726 PM EDT Mon Aug 30 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 815 PM EDT THIS 
EVENING FOR BRADLEY COUNTY...

At 726 PM EDT, local law enforcement reported several flooded 
roadways across the county. Up to 3 inches of rain have fallen. 
Additional rainfall amounts of 0.5 to 1 inch are possible in the 
warned area. Flash flooding is already occurring.

HAZARD...Flash flooding caused by thunderstorms.

SOURCE...Law enforcement reported.

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...
  Cleveland, East Cleveland, South Cleveland, Wildwood Lake, 
  Waterville, Flint Springs, Tasso, McDonald, Hopewell, Gap Springs, 
  Red Clay State Park and Apison.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Be aware of your surroundings and do not drive on flooded roads.

&&

LAT...LON 3529 8494 3518 8470 3509 8475 3508 8474
      3499 8478 3499 8497 3502 8496 3503 8499
      3505 8500 3506 8500 3508 8500 3508 8501
      3510 8501 3513 8503 3514 8503 3515 8502
      3515 8501 3517 8501

FLASH FLOOD...OBSERVED

$$

DH

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 30, 3:35 AM EDTFlash Flood WatchMRXAnderson, Bledsoe, Blount, Bradley, Campbell, Carter and 27 more48 hr
Aug 30, 1:22 PM EDTAreal Flood AdvisoryMRXCampbell113 min
Aug 30, 1:46 PM EDTSpecial Weather StatementMRXCampbell29 min
Aug 30, 2:13 PM EDTAreal Flood AdvisoryMRXCampbell2 hr
Aug 30, 3:25 PM EDTWind AdvisoryMRXBlount, Carter, Cocke, Greene, Monroe, Sevier and 1 more34 hr
Aug 30, 4:39 PM EDTAreal Flood AdvisoryMRXCampbell, Scott2 hr
Aug 30, 5:18 PM EDTSpecial Weather StatementMRXBradley, Hamilton, Polk57 min
Aug 30, 5:24 PM EDTAreal Flood AdvisoryMRXBradley, Hamilton, Meigs, Polk2 hr
Aug 30, 6:00 PM EDTSpecial Weather StatementMRXMcMinn, Meigs, Monroe, Rhea45 min
Aug 30, 6:06 PM EDTAreal Flood AdvisoryMRXBradley, McMinn, Meigs, Monroe, Polk, Rhea114 min
Aug 30, 6:52 PM EDTAreal Flood AdvisoryMRXMonroe113 min
Aug 30, 6:57 PM EDTSpecial Weather StatementMRXBledsoe, Blount, Loudon, McMinn, Meigs, Monroe and 2 more63 min
Aug 30, 7:00 PM EDTAreal Flood AdvisoryMRXAnderson, Blount, Knox, Loudon, Meigs, Monroe and 3 more2 hr
Aug 30, 7:47 PM EDTSpecial Weather StatementMRXBlount, Knox, Sevier58 min

Nearby

Flash Flood Warnings in Tennessee, 2021Every 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.