Alert archive / Tennessee / Flash Flood Watches in 2017

Flash Flood Watch 1, NWS Morristown, TN

April 22, 201733 counties in Tennessee; 7 counties in Virginia; Cherokee County, Clay County, North Carolina

NWS Morristown, TN issued this flash flood watch at Apr 22, 2017, 4:11 AM EDT for 33 counties in Tennessee; 7 counties in Virginia; Cherokee County, Clay County, North Carolina. It took effect at Apr 22, 2017, 2:00 PM EDT. It was in force for 37 hr.

The area

The counties it named.

The facts

Issued: Apr 22, 2017, 4:11 AM EDT (08:11 UTC)
In effect from: Apr 22, 2017, 2:00 PM EDT
Expired: Apr 24, 2017, 2:55 AM EDT
In force: 37 hr
Issued by: NWS Morristown, TN
Flood severity: None

All 42 counties

Cherokee County, NC, Clay County, NC, Anderson County, TN, Bledsoe County, TN, Blount County, TN, Bradley County, TN, Campbell County, TN, Carter County, TN, Claiborne County, TN, Cocke County, TN, Grainger County, TN, Greene County, TN, Hamblen County, TN, Hamilton County, TN, Hancock County, TN, Hawkins County, TN, Jefferson County, TN, Johnson County, TN, Knox County, TN, Loudon County, TN, Marion County, TN, McMinn County, TN, Meigs County, TN, Monroe County, TN, Morgan County, TN, Polk County, TN, Rhea County, TN, Roane County, TN, Scott County, TN, Sequatchie County, TN, Sevier County, TN, Sullivan County, TN, Unicoi County, TN, Union County, TN, Washington County, TN, City of Bristol, VA, City of Norton, VA, Lee County, VA, Russell County, VA, Scott County, VA, Washington County, VA, Wise County, VA

The radar

The Knoxville radar (KMRX), 27 km from the middle of the area, began a volume at 08:15 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, 8.2 hours before the alert went out and 265 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: 47 J/kg
Mixed-layer CIN: -72 J/kg
Mixed-layer LCL: 763 m above ground
0-6 km bulk shear: 49 kt
0-1 km storm-relative helicity: 133 m²/s²
0-3 km storm-relative helicity: 235 m²/s²
Significant tornado parameter: -0.0
Supercell composite: -0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this flash flood watch went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Morristown, TN wrote its last area forecast discussion before this flash flood watch went out at Apr 22, 3:51 AM EDT, 20 minutes earlier.

Area forecast discussion, Apr 22, 3:51 AM EDT, 20 minutes before

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The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 21, 9:37 PM EDT	Special Weather Statement	MRX	Monroe	53 min
Apr 22, 8:55 AM EDT	Areal Flood Advisory	MRX	Anderson, Campbell, Claiborne, Morgan, Scott, Union	4 hr
Apr 22, 9:14 AM EDT	River Flood Warning	MRX	Claiborne, Grainger, Hancock	4 days
Apr 22, 9:14 AM EDT	River Flood Warning	MRX	Hawkins, Sullivan	3 days
Apr 22, 11:04 AM EDT	Areal Flood Advisory	MRX	Hancock	3 hr
Apr 22, 4:40 PM EDT	Special Weather Statement	MRX	Anderson	50 min
Apr 22, 4:56 PM EDT	Severe Thunderstorm Warning	MRX	Anderson, Knox	64 min
Apr 22, 5:28 PM EDT	Areal Flood Advisory	MRX	Anderson, Blount, Grainger, Jefferson, Knox, Loudon and 4 more	3 hr
Apr 22, 5:33 PM EDT	Severe Thunderstorm Warning	MRX	Jefferson, Sevier	57 min
Apr 22, 5:44 PM EDT	Special Weather Statement	MRX	Sequatchie	46 min
Apr 22, 5:49 PM EDT	Flash Flood Warning	MRX	Anderson, Blount, Knox, Loudon, Morgan, Roane and 1 more	3 hr
Apr 22, 6:07 PM EDT	Severe Thunderstorm Warning	MRX	Bledsoe, Hamilton, Meigs, Rhea, Sequatchie	53 min
Apr 22, 6:19 PM EDT	Severe Thunderstorm Warning	MRX	Cocke	56 min
Apr 22, 6:29 PM EDT	Areal Flood Advisory	MRX	Bledsoe, Hamilton, Marion, Meigs, Rhea, Sequatchie	2 hr
Apr 22, 6:29 PM EDT	Special Weather Statement	MRX	Blount	46 min
Apr 22, 6:38 PM EDT	Severe Thunderstorm Warning	MRX	Loudon, McMinn, Monroe, Roane	51 min
Apr 22, 6:53 PM EDT	Areal Flood Warning	MRX	Anderson, Campbell, Morgan, Scott, Union	112 min
Apr 22, 7:06 PM EDT	River Flood Warning	MRX	Morgan, Roane	15 hr
Apr 22, 7:21 PM EDT	Special Weather Statement	MRX	Blount, Sevier	39 min
Apr 22, 7:24 PM EDT	Areal Flood Advisory	MRX	Carter, Claiborne, Grainger, Greene, Hamblen, Hancock and 5 more	3 hr
Apr 21, 8:03 PM EDT	Special Weather Statement	MRX	Washington, City of Bristol	42 min
Apr 22, 11:09 AM EDT	Special Weather Statement	MRX	Russell	51 min
Apr 22, 5:57 PM EDT	Areal Flood Advisory	MRX	Lee, Russell, Scott	3 hr
Apr 22, 12:29 PM EDT	Special Weather Statement	MRX	Watauga	31 min

Nearby

Flash Flood Watches in Tennessee, 2017 Flash Flood Watches in Virginia, 2017 Flash Flood Watches in North Carolina, 2017 Every flash flood watch in 2017

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.