Alert archive / Tennessee / Mesoscale Discussions in 2016

Mesoscale Discussion 339

April 6, 20165 states

The Storm Prediction Center issued this mesoscale discussion at Apr 6, 2016, 6:23 PM CDT for 5 states. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
Apr 6, 2016, 6:23 PM CDT (23:23 UTC)
Expired
Apr 6, 2016, 8:30 PM CDT
In force
2 hr
Issued by
the Storm Prediction Center
Chance of a watch
40%
All 97 counties

Bibb County, AL, Blount County, AL, Calhoun County, AL, Cherokee County, AL, Chilton County, AL, Clay County, AL, Cleburne County, AL, Colbert County, AL, Coosa County, AL, Cullman County, AL, DeKalb County, AL, Etowah County, AL, Fayette County, AL, Franklin County, AL, Greene County, AL, Hale County, AL, Jackson County, AL, Jefferson County, AL, Lamar County, AL, Lauderdale County, AL, Lawrence County, AL, Limestone County, AL, Madison County, AL, Marion County, AL, Marshall County, AL, Morgan County, AL, Perry County, AL, Pickens County, AL, Shelby County, AL, St. Clair County, AL, Sumter County, AL, Talladega County, AL, Tuscaloosa County, AL, Walker County, AL, Winston County, AL, Catoosa County, GA, Chattooga County, GA, Dade County, GA, Floyd County, GA, Gordon County, GA, Haralson County, GA, Murray County, GA, Polk County, GA, Walker County, GA, Whitfield County, GA, Clinton County, KY, Monroe County, KY, Chickasaw County, MS, Clay County, MS, Itawamba County, MS, Kemper County, MS, Lee County, MS, Lowndes County, MS, Monroe County, MS, Neshoba County, MS, Noxubee County, MS, Oktibbeha County, MS, Winston County, MS, Bedford County, TN, Bledsoe County, TN, Bradley County, TN, Cannon County, TN, Clay County, TN, Coffee County, TN, Cumberland County, TN, DeKalb County, TN, Fentress County, TN, Franklin County, TN, Giles County, TN, Grundy County, TN, Hamilton County, TN, Jackson County, TN, Lawrence County, TN, Lincoln County, TN, Macon County, TN, Marion County, TN, Marshall County, TN, Maury County, TN, McMinn County, TN, Meigs County, TN, Moore County, TN, Morgan County, TN, Overton County, TN, Pickett County, TN, Putnam County, TN, Rhea County, TN, Roane County, TN, Rutherford County, TN, Sequatchie County, TN, Smith County, TN, Sumner County, TN, Trousdale County, TN, Van Buren County, TN, Warren County, TN, White County, TN, Williamson County, TN, Wilson County, TN

The radar

The Northeast Alabama radar (KHTX), 81 km from the middle of the area, began a volume at 23:25 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

Birmingham, AL (KBMX), launched 12:00Z, 11.4 hours before the alert went out and 145 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, Birmingham, AL at 12:00Z on 2016-04-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Birmingham, AL at 12:00Z on 2016-04-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 268 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
2173 m above ground
0-6 km bulk shear
27 kt
0-1 km storm-relative helicity
268 m²/s²
0-3 km storm-relative helicity
343 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

362 
ACUS11 KWNS 062324
SWOMCD
SPC MCD 062323 
TNZ000-KYZ000-GAZ000-ALZ000-MSZ000-070130-

MESOSCALE DISCUSSION 0339
NWS STORM PREDICTION CENTER NORMAN OK
0623 PM CDT WED APR 06 2016

AREAS AFFECTED...FAR SOUTH-CENTRAL KY...PORTIONS OF MIDDLE INTO
EASTERN TN...EASTERN MS...NORTHERN/CENTRAL AL...AND NORTHWEST GA

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE 

VALID 062323Z - 070130Z

PROBABILITY OF WATCH ISSUANCE...40 PERCENT

SUMMARY...GUSTY WINDS WILL ACCOMPANY STORMS THIS EVENING. SPORADIC
STRONGER GUSTS MAY APPROACH SEVERE THRESHOLDS...BUT OVERALL THREAT
IS EXPECTED TO REMAIN LIMITED. A WATCH IS NOT EXPECTED AT THIS
TIME...BUT CONVECTIVE TRENDS WILL BE MONITORED CLOSELY.

DISCUSSION...AN INITIAL BAND OF STORMS ALONG A PRE-FRONTAL
CONFLUENCE ZONE FROM SOUTH-CENTRAL KY INTO NORTH-CENTRAL AL WAS
RESULTING IN SPORADIC GUSTY WINDS PER REPORTS FROM NWS LMK AND OHX.
ADDITIONAL THUNDERSTORMS WERE NOTED ALONG/JUST AHEAD OF THE SURFACE
COLD FRONT ACROSS NORTHERN MS TOWARD THE TN BORDER. MEAGER BOUNDARY
LAYER MOISTURE WITH SURFACE DEWPOINTS MAINLY IN THE 40S TO NEAR 50
DEG F AND TEMPERATURES IN THE 60S TO LOW 70S HAS RESULTED IN ONLY
WEAK DESTABILIZATION LATE THIS AFTERNOON. HOWEVER...STEEP LOW LEVEL
LAPSE RATES GREATER THAN 7.5 DEG C PER KM AND 0-1 KM SHEAR AROUND
35-45 KT WILL CONTINUE TO SUPPORT SPORADIC/MARGINALLY SEVERE WINDS
INTO THE EVENING HOURS. WHILE A WATCH DOES NOT APPEAR TO BE NEEDED
AT THIS TIME...TRENDS WILL BE MONITORED CLOSELY.

..LEITMAN/THOMPSON.. 04/06/2016

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

ATTN...WFO...MRX...JKL...FFC...LMK...OHX...BMX...HUN...MEG...
JAN...

LAT...LON   32908614 32508707 32378799 32538869 32668912 32968935
            33278927 33968904 34408865 35098758 36148679 36658636
            36808593 36818565 36748514 36538476 35768444 35098459
            34308481 33868512 32908614

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 6, 2:40 PM CDTMesoscale DiscussionSPCBallard, Caldwell, Calloway, Carlisle, Crittenden, Fulton and 11 more2 hr

Nearby

Mesoscale Discussions in Tennessee, 2016Mesoscale Discussions in Alabama, 2016Mesoscale Discussions in Mississippi, 2016Every mesoscale discussion in 2016

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.