Alert archive / Mississippi / Tornado Warnings in 2018

Tornado Warning 38, NWS Memphis, TN

August 20, 2018Lafayette County, Pontotoc County, Mississippi

NWS Memphis, TN issued this tornado warning at Aug 20, 2018, 7:31 PM CDT for Lafayette County, Pontotoc County, Mississippi. It was in force for 24 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: Aug 20, 2018, 7:31 PM CDT (00:31 UTC)
Expired: Aug 20, 2018, 7:55 PM CDT
In force: 24 min
Issued by: NWS Memphis, TN
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 1.25 in

Counties Lafayette County, MS, Pontotoc County, MS

The radar

The Columbus AFB radar (KGWX), 87 km from the middle of the area, began a volume at 00:31 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Aug 20, 4:45 PM CDT	Severe Thunderstorm Watch	SPC	6 hr

The nearest sounding before it

Little Rock, AR (KBYH), launched 00:00Z, 0.5 hours before the alert went out and 99 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: 72 J/kg
Mixed-layer CIN: -89 J/kg
Mixed-layer LCL: 1310 m above ground
0-6 km bulk shear: 29 kt
0-1 km storm-relative helicity: 28 m²/s²
0-3 km storm-relative helicity: 69 m²/s²
Significant tornado parameter: -0.0
Supercell composite: -0.1

Open this sounding in Storm Lab

The text

As transmitted.

987 
WFUS54 KMEG 210031
TORMEG
MSC071-115-210115-
/O.NEW.KMEG.TO.W.0038.180821T0031Z-180821T0115Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Memphis TN
731 PM CDT MON AUG 20 2018

The National Weather Service in Memphis has issued a

* Tornado Warning for...
  Southeastern Lafayette County in northwestern Mississippi...
  Central Pontotoc County in northeastern Mississippi...

* Until 815 PM CDT.
    
* At 731 PM CDT, doppler radar indicated a severe thunderstorm
  producing a tornado was located near Tula, or 15 miles southeast of
  Oxford, moving east at 20 mph.

  HAZARD...Tornado and half dollar size hail.

  SOURCE...Radar indicated rotation.

  IMPACT...Flying debris will be dangerous to those caught without 
           shelter. Mobile homes will be damaged or destroyed. 
           Damage to roofs, windows, and vehicles will occur.  Tree 
           damage is likely.

* Locations impacted include...
  Pontotoc, Tula, Randolph, Thaxton, Algoma, Toccopola, Nixon,
  Springville, Rough Edge, Pannell, Delay and Wallfield.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a storm shelter or an interior room on the
lowest floor of a sturdy building. Avoid windows. If you are
outdoors, in a mobile home, or in a vehicle, move to the closest
substantial shelter and protect yourself from flying debris.

&&

LAT...LON 3415 8924 3416 8925 3416 8928 3419 8938
      3430 8937 3434 8893 3407 8895
TIME...MOT...LOC 0031Z 273DEG 17KT 3423 8931 

TORNADO...RADAR INDICATED
HAIL...1.25IN

$$

1 follow-up statement

336 
WWUS54 KMEG 210055
SVSMEG

Severe Weather Statement
National Weather Service Memphis TN
755 PM CDT MON AUG 20 2018

MSC071-115-210105-
/O.CAN.KMEG.TO.W.0038.000000T0000Z-180821T0115Z/
Lafayette MS-Pontotoc MS-
755 PM CDT MON AUG 20 2018

...THE TORNADO WARNING FOR SOUTHEASTERN LAFAYETTE AND CENTRAL
PONTOTOC COUNTIES IS CANCELLED...
                
The storm which prompted the warning has weakened below severe
limits, and no longer appears capable of producing a tornado.
Therefore, the warning has been cancelled.

A Severe Thunderstorm Watch remains in effect until midnight CDT for
northeastern and northwestern Mississippi.

LAT...LON 3415 8924 3416 8925 3416 8928 3419 8938
      3430 8937 3434 8893 3407 8895
TIME...MOT...LOC 0053Z 273DEG 17KT 3422 8917 

$$

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 20, 7:01 PM CDT	Severe Thunderstorm Warning	MEG	Calhoun, Chickasaw	44 min
Aug 20, 7:23 PM CDT	Special Weather Statement	MEG	Quitman	22 min
Aug 20, 7:37 PM CDT	Severe Thunderstorm Warning	MEG	Chickasaw, Monroe	53 min
Aug 20, 8:18 PM CDT	Special Weather Statement	MEG	Itawamba	27 min
Aug 20, 8:31 PM CDT	Severe Thunderstorm Warning	MEG	Monroe	21 min
Aug 20, 10:43 PM CDT	Special Weather Statement	MEG	Monroe	17 min

Nearby

Tornado Warnings in Mississippi, 2018 Every tornado warning in 2018 Tornadoes in 2018

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.