Alert archive / Tennessee / Tornado Watches in 2020

Tornado Watch 92

April 8, 20205 counties in Arkansas; 43 counties in Tennessee

The Storm Prediction Center issued this tornado watch at Apr 8, 2020, 7:04 PM CDT for 5 counties in Arkansas; 43 counties in Tennessee. It was in force for 7 hr.

The area

The outline as issued.

The facts

Issued
Apr 8, 2020, 7:04 PM CDT (00:04 UTC)
Expired
Apr 9, 2020, 2:00 AM CDT
In force
7 hr
Issued by
the Storm Prediction Center
Largest hail expected
2.5 in
Strongest gust expected
60 kt
All 48 counties

Craighead County, AR, Crittenden County, AR, Cross County, AR, Mississippi County, AR, Poinsett County, AR, Benton County, TN, Carroll County, TN, Cheatham County, TN, Chester County, TN, Crockett County, TN, Davidson County, TN, Decatur County, TN, Dickson County, TN, Dyer County, TN, Fayette County, TN, Gibson County, TN, Giles County, TN, Hardeman County, TN, Hardin County, TN, Haywood County, TN, Henderson County, TN, Henry County, TN, Hickman County, TN, Houston County, TN, Humphreys County, TN, Lake County, TN, Lauderdale County, TN, Lawrence County, TN, Lewis County, TN, Macon County, TN, Madison County, TN, Maury County, TN, McNairy County, TN, Montgomery County, TN, Obion County, TN, Perry County, TN, Robertson County, TN, Rutherford County, TN, Shelby County, TN, Smith County, TN, Stewart County, TN, Sumner County, TN, Tipton County, TN, Trousdale County, TN, Wayne County, TN, Weakley County, TN, Williamson County, TN, Wilson County, TN

The radar

The Memphis radar (KNQA), 105 km from the middle of the area, began a volume at 00:06 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 SPC expected

The probabilities SPC published with the watch, for the watch area over its life.

Two or more tornadoes
60%
One or more EF2 to EF5 tornadoes
20%
Ten or more severe wind reports
80%
One or more gusts of 65 knots or more
10%
Ten or more severe hail reports
80%
One or more hailstones of 2 inches or more
60%
Six or more combined severe hail and wind reports
95%

Warnings issued inside it

27 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
Apr 8, 7:06 PM CDTSevere Thunderstorm WarningMEGCraighead, Poinsett39 min
Apr 8, 7:35 PM CDTTornado WarningMEGCraighead, Poinsett25 min
Apr 8, 7:53 PM CDTTornado Warning Tornado observedMEGCraighead, Poinsett52 min
Apr 8, 7:57 PM CDTSevere Thunderstorm WarningMEGCraighead, Poinsett48 min
Apr 8, 7:58 PM CDTSevere Thunderstorm WarningMEGBenton, Henry47 min
Apr 8, 8:13 PM CDTSevere Thunderstorm WarningOHXHouston, Montgomery, Stewart47 min
Apr 8, 8:33 PM CDTSevere Thunderstorm WarningMEGCrockett, Dyer, Gibson, Haywood, Lauderdale42 min
Apr 8, 8:36 PM CDTTornado WarningMEGCrittenden, Cross, Poinsett26 min
Apr 8, 8:37 PM CDTSevere Thunderstorm WarningMEGBenton, Henry, Weakley38 min
Apr 8, 8:57 PM CDTSevere Thunderstorm WarningOHXDickson, Houston, Montgomery, Robertson, Stewart33 min
Apr 8, 9:00 PM CDTSevere Thunderstorm WarningMEGCrittenden, Mississippi, Poinsett45 min
Apr 8, 9:04 PM CDTSevere Thunderstorm WarningMEGBenton, Carroll, Henry41 min
Apr 8, 9:11 PM CDTSevere Thunderstorm WarningOHXHouston, Humphreys, Stewart34 min
Apr 8, 9:17 PM CDTSevere Thunderstorm WarningOHXCheatham, Davidson, Dickson, Montgomery, Robertson28 min
Apr 8, 9:36 PM CDTSevere Thunderstorm WarningMEGCrittenden39 min
Apr 8, 9:36 PM CDTSevere Thunderstorm WarningOHXDavidson, Macon, Robertson, Sumner, Wilson39 min
Apr 8, 9:41 PM CDTSevere Thunderstorm WarningOHXCheatham, Davidson, Dickson, Williamson, Wilson34 min
Apr 8, 10:09 PM CDTSevere Thunderstorm WarningOHXDeKalb, Jackson, Macon, Smith, Sumner, Trousdale and 1 more36 min
Apr 8, 10:12 PM CDTSevere Thunderstorm WarningMEGClay, Greene, Mississippi48 min
Apr 8, 10:14 PM CDTSevere Thunderstorm WarningOHXDavidson, Rutherford, Wilson46 min
Apr 8, 10:17 PM CDTSevere Thunderstorm WarningMEGFayette, Shelby28 min
Apr 8, 10:43 PM CDTSevere Thunderstorm WarningOHXCannon, DeKalb, Rutherford, Smith, Warren, Wilson47 min
Apr 8, 10:46 PM CDTSevere Thunderstorm WarningMEGFayette, Hardeman44 min
Apr 8, 10:48 PM CDTSevere Thunderstorm WarningMEGMississippi42 min
Apr 8, 10:54 PM CDTSevere Thunderstorm WarningMEGCraighead, Mississippi51 min
Apr 8, 11:38 PM CDTSevere Thunderstorm WarningMEGMississippi52 min
Apr 9, 12:31 AM CDTSevere Thunderstorm WarningMEGHardin, McNairy44 min

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Little Rock, AR (KLZK), launched 00:00Z, 0.1 hours before the alert went out and 151 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, Little Rock, AR at 00:00Z on 2020-04-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1810 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Little Rock, AR at 00:00Z on 2020-04-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 113 square meters per square second.1939587897117Sfc1 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
1810 J/kg
Mixed-layer CIN
-112 J/kg
Mixed-layer LCL
1529 m above ground
0-6 km bulk shear
56 kt
0-1 km storm-relative helicity
113 m²/s²
0-3 km storm-relative helicity
132 m²/s²
Significant tornado parameter
0.4
Supercell composite
8.3

Open this sounding in Storm Lab

The text

As transmitted.

473 
WWUS20 KWNS 090003
SEL2  
SPC WW 090003
ARZ000-TNZ000-090700-

URGENT - IMMEDIATE BROADCAST REQUESTED
Tornado Watch Number 92
NWS Storm Prediction Center Norman OK
705 PM CDT Wed Apr 8 2020

The NWS Storm Prediction Center has issued a

* Tornado Watch for portions of 
  Northeast Arkansas
  Western and Middle Tennessee

* Effective this Wednesday night and Thursday morning from 705 PM
  until 200 AM CDT.

* Primary threats include...
  A few tornadoes likely
  Widespread large hail and isolated very large hail events to 2.5
    inches in diameter likely
  Widespread damaging wind gusts to 70 mph likely

SUMMARY...A broken line of thunderstorms currently extending from
northern Arkansas into southeast Missouri will sag southeastward
into the watch area this evening.  Large hail and damaging wind
gusts will be possible in the stronger cells, along with an
increasing risk of a few tornadoes after dark.

The tornado watch area is approximately along and 45 statute miles
north and south of a line from 25 miles southwest of Jonesboro AR to
40 miles east of Nashville TN. For a complete depiction of the watch
see the associated watch outline update (WOUS64 KWNS WOU2).

PRECAUTIONARY/PREPAREDNESS ACTIONS...

REMEMBER...A Tornado Watch means conditions are favorable for
tornadoes and severe thunderstorms in and close to the watch
area. Persons in these areas should be on the lookout for
threatening weather conditions and listen for later statements
and possible warnings.

&&

OTHER WATCH INFORMATION...CONTINUE...WW 88...WW 89...WW 90...WW
91...

AVIATION...Tornadoes and a few severe thunderstorms with hail
surface and aloft to 2.5 inches. Extreme turbulence and surface wind
gusts to 60 knots. A few cumulonimbi with maximum tops to 500. Mean
storm motion vector 28035.

...Hart

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 8, 7:46 PM CDTMesoscale DiscussionSPCAnderson, Ballard, Boone, Bourbon, Boyle, Bracken and 61 more119 min
Apr 8, 9:14 PM CDTMesoscale DiscussionSPCBath, Boyd, Breathitt, Carter, Clay, Elliott and 30 more3 hr
Apr 8, 9:51 PM CDTTornado WatchSPCBath, Bell, Boyd, Breathitt, Carter, Clay and 31 more5 hr
Apr 8, 9:52 PM CDTMesoscale DiscussionSPCAnderson, Bedford, Bledsoe, Blount, Bradley, Cannon and 32 more113 min
Apr 8, 10:16 PM CDTSevere Thunderstorm WatchSPCAnderson, Bedford, Bledsoe, Blount, Bradley, Campbell and 46 more6 hr

Nearby

Tornado Watches in Tennessee, 2020Tornado Watches in Arkansas, 2020Every tornado watch in 2020

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.