Alert archive / Mississippi / Mesoscale Discussions in 2011

Mesoscale Discussion 1127

June 7, 2011Washington Parish, Louisiana; 34 counties in Mississippi

The Storm Prediction Center issued this mesoscale discussion at Jun 7, 2011, 2:01 PM CDT for Washington Parish, Louisiana; 34 counties in Mississippi. It was in force for 59 min.

The area

The outline as issued.

The facts

Issued: Jun 7, 2011, 2:01 PM CDT (19:01 UTC)
Expired: Jun 7, 2011, 3:00 PM CDT
In force: 59 min
Issued by: the Storm Prediction Center

All 35 counties

Washington Parish, LA, Claiborne County, MS, Copiah County, MS, Covington County, MS, Forrest County, MS, George County, MS, Greene County, MS, Hancock County, MS, Harrison County, MS, Hinds County, MS, Jackson County, MS, Jasper County, MS, Jefferson Davis County, MS, Jones County, MS, Lamar County, MS, Lawrence County, MS, Leake County, MS, Lincoln County, MS, Madison County, MS, Marion County, MS, Neshoba County, MS, Newton County, MS, Pearl River County, MS, Perry County, MS, Pike County, MS, Rankin County, MS, Scott County, MS, Sharkey County, MS, Simpson County, MS, Smith County, MS, Stone County, MS, Walthall County, MS, Warren County, MS, Wayne County, MS, Yazoo County, MS

The radar

The Jackson/Brandon,MS radar (KDGX), 75 km from the middle of the area, began a volume at 19:03 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

Jackson, MS (KJAN), launched 12:00Z, 7.0 hours before the alert went out and 81 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: 1725 J/kg
Mixed-layer CIN: -95 J/kg
Mixed-layer LCL: 1495 m above ground
0-6 km bulk shear: 17 kt
0-1 km storm-relative helicity: -9 m²/s²
0-3 km storm-relative helicity: -4 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.4

Open this sounding in Storm Lab

The text

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

655 
ACUS11 KWNS 071902
SWOMCD
SPC MCD 071901
MSZ000-LAZ000-072000-

MESOSCALE DISCUSSION 1127
NWS STORM PREDICTION CENTER NORMAN OK
0201 PM CDT TUE JUN 07 2011

AREAS AFFECTED...SRN HALF OF MS

CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY

VALID 071901Z - 072000Z

SCATTERED STORMS ARE EXPECTED TO DEVELOP OVER THE NEXT FEW HOURS
ACROSS THE SRN HALF OF MS.  MICROBURSTS CAPABLE OF ISOLD POCKETS OF
WIND DAMAGE WILL BE PROBABLE THIS AFTERNOON.

VISIBLE SATELLITE/SURFACE COMPOSITE SHOWS AN AGITATED CU FIELD
BEGINNING TO BLOSSOM INTO PULSE STORMS AS TEMPS WARM THROUGH THE MID
90S THIS AFTERNOON.  DUE TO STRONG HEATING...STEEP LOW LEVEL LAPSE
RATES NEARING DRY ADIABATIC HAVE DEVELOPED.  THIS IS AHEAD OF A WWD
MOVING MCV LOCATED NEAR THE MS COAST.  BOTH KLIX AND KMOB SHOW FLOW
IN THE 6-8 KM LAYER IN THE 25-35 KT RANGE WHICH WILL SUPPORT WWD
PROPAGATION/SOME CONTRIBUTION IN ORGANIZING COLD POOLS SUCH THAT
THERE MAY BE LOCALLY MAXIMIZED BACKGROUND DMGG WIND POTENTIAL OVER
THIS REGION.  CURRENT THINKING IS A PULSE TSTM MODE WILL BE FAVORED
INITIALLY BEFORE SOME CONSOLIDATION OF COLD POOLS RESULTS IN A
CLUSTER OF STORMS.  IN SUMMARY...A THREAT FOR SOME STRONG TO
LOWER-END SEVERE WIND GUSTS RESULTANT FROM WET MICROBURSTS--CAPABLE
OF SPORADIC POCKETS OF WIND DAMAGE-- WILL BE PROBABLE THIS
AFTERNOON.  CONVECTIVE TRENDS WILL BE MONITORED FOR UPSCALE GROWTH
IN THE NEXT HOUR OR TWO IN CASE THE THREAT IS MORE WIDESPREAD THAN
CURRENTLY ANTICIPATED.

..SMITH.. 06/07/2011

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

ATTN...WFO...MOB...JAN...LIX...

LAT...LON   30769045 32259121 32959089 33168990 32878903 31158850
            30478848 30278936 30769045

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jun 7, 6:04 PM CDT	Mesoscale Discussion	SPC	Avoyelles, Caldwell, Catahoula, Concordia, East Carroll, East Feliciana and 14 more	116 min

Nearby

Mesoscale Discussions in Mississippi, 2011 Mesoscale Discussions in Louisiana, 2011 Every mesoscale discussion in 2011

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.