Alert archive / Alabama / Mesoscale Discussions in 2012

Mesoscale Discussion 1028

June 3, 201223 counties in Alabama; 6 counties in Mississippi

The Storm Prediction Center issued this mesoscale discussion at Jun 3, 2012, 1:11 PM CDT for 23 counties in Alabama; 6 counties in Mississippi. It was in force for 64 min.

The area

The outline as issued.

The facts

Issued: Jun 3, 2012, 1:11 PM CDT (18:11 UTC)
Expired: Jun 3, 2012, 2:15 PM CDT
In force: 64 min
Issued by: the Storm Prediction Center
Chance of a watch: 80%

All 29 counties

Blount County, AL, Calhoun County, AL, Cherokee County, AL, Clay County, AL, Colbert County, AL, Coosa County, AL, Cullman County, AL, Etowah County, AL, Fayette County, AL, Franklin County, AL, Jefferson County, AL, Lamar County, AL, Lawrence County, AL, Marion County, AL, Marshall County, AL, Morgan County, AL, Pickens County, AL, Shelby County, AL, St. Clair County, AL, Talladega County, AL, Tuscaloosa County, AL, Walker County, AL, Winston County, AL, Itawamba County, MS, Lee County, MS, Lowndes County, MS, Monroe County, MS, Prentiss County, MS, Tishomingo County, MS

The radar

The Columbus AFB radar (KGWX), 88 km from the middle of the area, began a volume at 18:12 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 watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

The nearest sounding before it

Birmingham, AL (KBMX), launched 12:00Z, 6.2 hours before the alert went out and 95 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1403 m above ground
0-6 km bulk shear: 39 kt
0-1 km storm-relative helicity: 186 m²/s²
0-3 km storm-relative helicity: 287 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

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

968 
ACUS11 KWNS 031812
SWOMCD
SPC MCD 031811
ALZ000-MSZ000-031915-

MESOSCALE DISCUSSION 1028
NWS STORM PREDICTION CENTER NORMAN OK
0111 PM CDT SUN JUN 03 2012

AREAS AFFECTED...MS...AL

CONCERNING...SEVERE POTENTIAL...SEVERE THUNDERSTORM WATCH LIKELY

VALID 031811Z - 031915Z

PROBABILITY OF WATCH ISSUANCE...80 PERCENT

SUMMARY...CHANCES ARE INCREASING THAT SEVERE STORMS WITH HAIL AND
HIGH WINDS WILL SPREAD EAST FROM NRN MS INTO PARTS OF NRN/CNTRL AL
THROUGH THE AFTERNOON. A SEVERE THUNDERSTORM WATCH WILL LIKELY BE
NEEDED AHEAD OF THIS DEVELOPMENT.

DISCUSSION...SCATTERED STRONG TO SEVERE STORMS ARE EXPECTED TO
INCREASE IN BOTH COVERAGE AND INTENSITY ALONG A WEAK WARM FRONTAL
ZONE DRAPED OVER NRN MS/AL. LIFT ALONG/ACROSS THIS BOUNDARY IS AIDED
BY A 20-30KT WLY LOW LEVEL JET AND MODEST 30KT NWLY FLOW AT MID
LEVELS WILL CONTRIBUTE TO SUFFICIENT SHEAR TO MAINTAIN UPDRAFT
ORGANIZATION AND PERSISTENCE. AIRMASS ALONG AND SOUTH OF THE
BOUNDARY IS VERY UNSTABLE ACROSS MS BUT LESS SO TO THE NORTH OF THE
BOUNDARY...OVER NRN AL. HOWEVER...LATEST SATL IMAGERY INDICATES THAT
STRONG HEATING SHOULD CONTINUE ACROSS NRN AL IN ADVANCE OF THE
ONGOING CONVECTION AND ADDITIONAL CELLS MAY DEVELOP ALONG THE FRONT
AND MOVE INTO AL THROUGH THE AFTERNOON. SOMEWHAT DRIER BOUNDARY
LAYER IN THIS REGION MAY SUPPORT DOWNBURST WIND POTENTIAL. IN
ADDITION TO LOCALLY STRONG DOWNBURST WINDS...LARGE HAIL IS POSSIBLE
WITH ANY OF THE PERSISTENT ROTATING STORMS GIVEN MAGNITUDE OF
AVAILABLE INSTABILITY TO THIS DEVELOPING CONVECTION.

..CARBIN.. 06/03/2012

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

ATTN...WFO...BMX...HUN...MEG...JAN...

LAT...LON   33128733 33358842 33888891 34328894 34828877 34928794
            34628617 34198549 33308564 32908624 33128733

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jun 3, 1:26 PM CDT	Severe Thunderstorm Watch	SPC	Bibb, Blount, Calhoun, Chambers, Chilton, Clay and 27 more	5 hr
Jun 3, 3:47 PM CDT	Mesoscale Discussion	SPC	Bibb, Blount, Calhoun, Clay, Cleburne, Cullman and 10 more	88 min
Jun 3, 4:39 PM CDT	Mesoscale Discussion	SPC	Autauga, Bibb, Bullock, Chambers, Chilton, Coosa and 11 more	66 min
Jun 3, 5:02 PM CDT	Mesoscale Discussion	SPC	Alcorn, Benton, Coahoma, DeSoto, Lafayette, Marshall and 9 more	88 min

Nearby

Mesoscale Discussions in Alabama, 2012 Mesoscale Discussions in Mississippi, 2012 Every 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.