Alert archive / Tennessee / Mesoscale Discussions in 2012

Mesoscale Discussion 1068

June 5, 201212 counties in Tennessee

The Storm Prediction Center issued this mesoscale discussion at Jun 5, 2012, 1:49 AM CDT for 12 counties in Tennessee. It was in force for 56 min.

The area

The outline as issued.

The facts

Issued
Jun 5, 2012, 1:49 AM CDT (06:49 UTC)
Expired
Jun 5, 2012, 2:45 AM CDT
In force
56 min
Issued by
the Storm Prediction Center

Counties Chester County, TN, Decatur County, TN, Giles County, TN, Hardin County, TN, Henderson County, TN, Lawrence County, TN, Lewis County, TN, Marshall County, TN, Maury County, TN, McNairy County, TN, Perry County, TN, Wayne County, TN

The radar

The Nashville radar (KOHX), 151 km from the middle of the area, began a volume at 06:51 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, 6.8 hours before the alert went out and 140 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 00:00Z on 2012-06-05Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 162 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, Nashville Metro, TN at 00:00Z on 2012-06-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -9 square meters per square second.19395878Sfc1 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
162 J/kg
Mixed-layer CIN
-67 J/kg
Mixed-layer LCL
1734 m above ground
0-6 km bulk shear
37 kt
0-1 km storm-relative helicity
-9 m²/s²
0-3 km storm-relative helicity
136 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

901 
ACUS11 KWNS 050649
SWOMCD
SPC MCD 050649 
TNZ000-ALZ000-050745-

MESOSCALE DISCUSSION 1068
NWS STORM PREDICTION CENTER NORMAN OK
0149 AM CDT TUE JUN 05 2012

AREAS AFFECTED...SWRN THROUGH SRN MIDDLE TN

CONCERNING...SEVERE THUNDERSTORM WATCH 357...

VALID 050649Z - 050745Z

THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 357
CONTINUES.

SUMMARY...STORMS MAY REMAIN CAPABLE OF ISOLATED STRONG WIND GUSTS
OVER A PORTION OF SWRN TN DURING THE NEXT HOUR...BUT OVERALL SEVERE
THREAT IS BECOMING INCREASINGLY MARGINAL. STORMS SHOULD BEGIN MOVING
SOUTH OF WW 357 BY 08Z...BUT ANOTHER WW IS NOT ANTICIPATED.

DISCUSSION...A CLUSTER OF MULTICELLS CONTINUES MOVING SOUTH THROUGH
A PORTION OF WRN AND MIDDLE TN AT AROUND 25 KT. ACTIVITY IS EMBEDDED
IN WEAK VERTICAL SHEAR AND MARGINAL INSTABILITY. SOME BACKBUILDING
HAS BEEN NOTED ON WRN FLANK...AND ISOLATED STRONG WIND GUSTS REMAIN
POSSIBLE AS ACTIVITY DEVELOPS SWD. HOWEVER...OVERALL THREAT IS
EXPECTED TO CONTINUE A GRADUAL DECREASE.

..DIAL.. 06/05/2012

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...OHX...HUN...MEG...

LAT...LON   35628871 35838789 35478651 34978693 35088863 35628871

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 4, 9:11 PM CDTMesoscale DiscussionSPCBedford, Benton, Carroll, Cheatham, Chester, Crockett and 35 more94 min
Jun 4, 9:43 PM CDTSevere Thunderstorm WatchSPCBedford, Benton, Carroll, Cheatham, Chester, Crockett and 34 more6 hr

Nearby

Mesoscale Discussions in Tennessee, 2012Every mesoscale discussion in 2012

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.