Alert archive / Tennessee / Flash Flood Warnings in 2021
Flash Flood Warning 31, NWS Morristown, TN
NWS Morristown, TN issued this flash flood warning at Jul 18, 2021, 5:18 PM EDT for 5 counties in Tennessee. It was in force for 2 hr. No storm report in the archive falls inside the area while it was in force.
The area
The outline as issued.
The facts
- Issued
- Jul 18, 2021, 5:18 PM EDT (21:18 UTC)
- Expired
- Jul 18, 2021, 7:25 PM EDT
- In force
- 2 hr
- Issued by
- NWS Morristown, TN
- Area
- Storm-based polygon
- Flood severity
- None
Counties Anderson County, TN, Jefferson County, TN, Knox County, TN, Roane County, TN, Sevier County, TN
The radar
The Knoxville radar (KMRX), 70 km from the middle of the area, began a volume at 21:17 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, 9.3 hours before the alert went out and 224 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.
- Mixed-layer CAPE
- 949 J/kg
- Mixed-layer CIN
- -37 J/kg
- Mixed-layer LCL
- 588 m above ground
- 0-6 km bulk shear
- 6 kt
- 0-1 km storm-relative helicity
- -6 m²/s²
- 0-3 km storm-relative helicity
- 0 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
941
WGUS54 KMRX 182118
FFWMRX
TNC001-089-093-145-155-182345-
/O.NEW.KMRX.FF.W.0031.210718T2118Z-210718T2345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Morristown TN
518 PM EDT Sun Jul 18 2021
The National Weather Service in Morristown has issued a
* Flash Flood Warning for...
South Central Anderson County in east Tennessee...
Southwestern Jefferson County in east Tennessee...
Central Knox County in east Tennessee...
Northeastern Roane County in east Tennessee...
Northwestern Sevier County in east Tennessee...
* Until 745 PM EDT.
* At 518 PM EDT, Doppler radar indicated thunderstorms producing
heavy rain across the warned area. Between 2.5 and 3 inches of
rain have fallen. Additional rainfall amounts of 0.5 to 1 inch are
possible in the warned area. 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...
Knoxville, Oak Ridge, Sevierville, Alcoa, Dandridge, Farragut,
Lake Forest, Bearden, Kimberlin Heights, Seymour, McMahan, Karns,
Kodak and Piedmont.
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.
Please report observed flooding to local emergency services or law
enforcement and request they pass this information to the National
Weather Service when you can do so safely.
&&
LAT...LON 3588 8433 3589 8439 3600 8438 3604 8341
3592 8337 3588 8397 3588 8424 3590 8428
3588 8428 3589 8433
FLASH FLOOD...RADAR INDICATED
$$
TD3 follow-up statements
595
WGUS74 KMRX 182152
FFSMRX
Flash Flood Statement
National Weather Service Morristown TN
552 PM EDT Sun Jul 18 2021
TNC089-155-182202-
/O.CAN.KMRX.FF.W.0031.000000T0000Z-210718T2345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Jefferson TN-Sevier TN-
552 PM EDT Sun Jul 18 2021
...FLASH FLOOD WARNING IS CANCELLED FOR SOUTHWESTERN JEFFERSON AND
NORTHWESTERN SEVIER COUNTIES...
Flooding is no longer expected to pose a threat. Please continue to
heed remaining road closures.
LAT...LON 3588 8433 3589 8439 3600 8438 3602 8385
3589 8383 3588 8397 3588 8424 3590 8428
3589 8429 3588 8428 3589 8433
$$
TNC001-093-145-182345-
/O.CON.KMRX.FF.W.0031.000000T0000Z-210718T2345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Anderson TN-Knox TN-Roane TN-
552 PM EDT Sun Jul 18 2021
...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 745 PM EDT THIS
EVENING FOR SOUTH CENTRAL ANDERSON, CENTRAL KNOX AND NORTHEASTERN
ROANE COUNTIES...
At 552 PM EDT, Doppler radar indicated thunderstorms producing heavy
rain across the warned area. Between 2.5 and 3 inches of rain have
fallen. Additional rainfall amounts of 0.5 inch are possible in the
warned area during the next hour. Flash flooding is expected to
continue at least for the next hour.
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...
Knoxville, Oak Ridge, Alcoa, Farragut, Karns, Bearden and Lake
Forest.
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.
Please report observed flooding to local emergency services or law
enforcement and request they pass this information to the National
Weather Service when you can do so safely.
&&
LAT...LON 3588 8433 3589 8439 3600 8438 3602 8385
3589 8383 3588 8397 3588 8424 3590 8428
3589 8429 3588 8428 3589 8433
FLASH FLOOD...RADAR INDICATED
$$
TD857
WGUS74 KMRX 182300
FFSMRX
Flash Flood Statement
National Weather Service Morristown TN
700 PM EDT Sun Jul 18 2021
TNC001-093-145-182345-
/O.CON.KMRX.FF.W.0031.000000T0000Z-210718T2345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Anderson TN-Knox TN-Roane TN-
700 PM EDT Sun Jul 18 2021
...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 745 PM EDT THIS
EVENING FOR SOUTH CENTRAL ANDERSON, CENTRAL KNOX AND NORTHEASTERN
ROANE COUNTIES...
At 700 PM EDT, Doppler radar indicated that the thunderstorms
producing heavy rainfall had moved out of the warned area. Between
2.5 and 3 inches of rain was estimated to have fallen. Additional
rainfall amounts up to 0.5 inch are still possible in the warned
area as light to moderate rainfall continues over part of the area
through 745 pm.
HAZARD...Flash flooding caused by thunderstorms.
SOURCE...Radar.
IMPACT...Flash flooding of small creeks and streams, urban areas,
highways, streets and underpasses as well as other poor
drainage and low-lying areas.
Some locations that may still experience flash flooding include...
Knoxville, Oak Ridge, Alcoa, Farragut, Karns, Bearden and Lake
Forest.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
Be aware of your surroundings and do not drive through flooded roads.
Please report observed flooding to local emergency services or law
enforcement and request they pass this information to the National
Weather Service when you can do so safely.
&&
LAT...LON 3588 8433 3589 8439 3600 8438 3602 8385
3589 8383 3588 8397 3588 8424 3590 8428
3589 8429 3588 8428 3589 8433
FLASH FLOOD...RADAR INDICATED
$$
TD769
WGUS74 KMRX 182325
FFSMRX
Flash Flood Statement
National Weather Service Morristown TN
725 PM EDT Sun Jul 18 2021
TNC001-093-145-182335-
/O.CAN.KMRX.FF.W.0031.000000T0000Z-210718T2345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Anderson TN-Knox TN-Roane TN-
725 PM EDT Sun Jul 18 2021
...FLASH FLOOD WARNING IS CANCELLED FOR SOUTH CENTRAL ANDERSON,
CENTRAL KNOX AND NORTHEASTERN ROANE COUNTIES...
Flood waters have receded. The heavy rain has ended. Flooding is no
longer expected to pose a threat. Please continue to heed any
remaining road closures.
LAT...LON 3588 8433 3589 8439 3600 8438 3602 8385
3589 8383 3588 8397 3588 8424 3590 8428
3589 8429 3588 8428 3589 8433
$$
TDThe office that day
Everything else NWS Morristown, TN issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 18, 4:20 PM EDT | Special Weather Statement | MRX | Scott | 40 min |
| Jul 18, 4:46 PM EDT | Areal Flood Advisory | MRX | Anderson, Jefferson, Knox, Roane, Sevier | 3 hr |
| Jul 18, 4:53 PM EDT | Areal Flood Advisory | MRX | Scott | 3 hr |
| Jul 18, 5:09 PM EDT | Areal Flood Advisory | MRX | Morgan, Roane | 3 hr |
| Jul 18, 5:10 PM EDT | Areal Flood Advisory | MRX | Cocke, Hamblen, Jefferson | 110 min |
| Jul 18, 6:07 PM EDT | Areal Flood Advisory | MRX | Claiborne, Grainger, Hancock, Hawkins | 113 min |
| Jul 18, 6:48 PM EDT | Areal Flood Advisory | MRX | Loudon, Roane | 117 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.