Alert archive / Mississippi / Mesoscale Discussions in 2016

Mesoscale Discussion 84

February 2, 20167 counties in Alabama; 5 parishes in Louisiana; 34 counties in Mississippi

The Storm Prediction Center issued this mesoscale discussion at Feb 2, 2016, 10:23 PM CST for 7 counties in Alabama; 5 parishes in Louisiana; 34 counties in Mississippi. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued: Feb 2, 2016, 10:23 PM CST (04:23 UTC)
Expired: Feb 3, 2016, 12:30 AM CST
In force: 2 hr
Issued by: the Storm Prediction Center

All 46 counties

Baldwin County, AL, Choctaw County, AL, Clarke County, AL, Mobile County, AL, Monroe County, AL, Washington County, AL, Wilcox County, AL, East Feliciana Parish, LA, Saint Helena Parish, LA, Saint Tammany Parish, LA, Tangipahoa Parish, LA, Washington Parish, LA, Amite County, MS, Clarke County, MS, Clay County, MS, Covington County, MS, Forrest County, MS, George County, MS, Greene County, MS, Hancock County, MS, Harrison County, MS, Jackson County, MS, Jasper County, MS, Jefferson Davis County, MS, Jones County, MS, Kemper County, MS, Lamar County, MS, Lauderdale County, MS, Leake County, MS, Lowndes County, MS, Marion County, MS, Neshoba County, MS, Newton County, MS, Noxubee County, MS, Oktibbeha County, MS, Pearl River County, MS, Perry County, MS, Pike County, MS, Scott County, MS, Simpson County, MS, Smith County, MS, Stone County, MS, Walthall County, MS, Wayne County, MS, Wilkinson County, MS, Winston County, MS

The radar

The Jackson/Brandon,MS radar (KDGX), 117 km from the middle of the area, began a volume at 04:26 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 00:00Z, 4.4 hours before the alert went out and 127 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: 364 J/kg
Mixed-layer CIN: -70 J/kg
Mixed-layer LCL: 893 m above ground
0-6 km bulk shear: 57 kt
0-1 km storm-relative helicity: 204 m²/s²
0-3 km storm-relative helicity: 226 m²/s²
Significant tornado parameter: 0.4
Supercell composite: 1.3

Open this sounding in Storm Lab

The text

As transmitted.

533 
ACUS11 KWNS 030424
SWOMCD
SPC MCD 030423 
ALZ000-FLZ000-MSZ000-LAZ000-030630-

MESOSCALE DISCUSSION 0084
NWS STORM PREDICTION CENTER NORMAN OK
1023 PM CST TUE FEB 02 2016

AREAS AFFECTED...MS...SW AL...SE LA

CONCERNING...SEVERE THUNDERSTORM WATCH 12...

VALID 030423Z - 030630Z

THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 12
CONTINUES.

SUMMARY...THE SEVERE THREAT ONGOING IN THE WRN PART OF WW 12 WILL
CONTINUE THROUGH THE EVENING AND INTO THE OVERNIGHT PERIOD. AN
ISOLATED TORNADO THREAT AND POTENTIAL FOR WIND DAMAGE WILL CONTINUE
WITH THE MORE ORGANIZED STORMS.

DISCUSSION...LATEST SFC ANALYSIS SHOWS A COLD FRONT EXTENDING SWWD
ACROSS LA WITH A PRE-FRONTAL TROUGH LOCATED IN SW MS AND SE LA. A
LINE OF STRONG THUNDERSTORMS IS ONGOING ALONG THE PRE-FRONTAL
TROUGH. AHEAD OF THE LINE...SFC DEWPOINTS ARE IN THE UPPER 60S TO
NEAR 70 F WHICH IS CONTRIBUTING TO WEAK INSTABILITY ACROSS WARM
SECTOR WITH MLCAPE VALUES ESTIMATED IN THE 500 TO 750 J/KG RANGE. IN
SPITE OF THE WEAK INSTABILITY...STRONG DEEP-LAYER SHEAR IS EVIDENT
ON THE NEW ORLEANS WSR-88D VWP WITH 0-6 KM SHEAR NEAR 70 KT. IN
ADDITION...50 KT OF SLY FLOW IS PRESENT JUST ABOVE THE SFC WHICH
SHOULD MAKE CONDITIONS FAVORABLE FOR DAMAGING WIND GUSTS WITH THE
BETTER ORGANIZED LINE SEGMENTS. THE STRONG LOW-LEVEL SHEAR WILL ALSO
MAKE A TORNADO OR TWO POSSIBLE MAINLY WITH ROTATING CELLS EMBEDDED
IN THE LINE OR WITH MORE DISCRETE CELLS THAT DEVELOP AHEAD OF THE
LINE LATE THIS EVENING INTO THE EARLY OVERNIGHT PERIOD.

..BROYLES.. 02/03/2016

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

ATTN...WFO...BMX...MOB...MEG...JAN...LIX...

LAT...LON   30218796 30228776 30298752 30368743 30458746 30578738
            30738749 30888762 31048765 31258759 31258735 31408725
            31598713 31738707 31778690 32048690 32018712 32188732
            32268750 32138753 32148761 32018766 31988789 32028812
            32128804 32318797 32338843 33748826 33678848 33668871
            33808870 33808894 33728895 33718901 33598900 33578909
            33188909 33198919 33148923 33098931 32928933 32938973
            32648971 32648983 32288970 32008977 32029024 31769009
            31728995 31408999 31429008 31309006 31329095 31389120
            31349143 31219154 31139162 31059160 30989120 30729128
            30719090 30699090 30659061 30419051 30339034 30419023
            30359005 30258987 30188959 30108953 30068935 30198915
            30178894 30248868 30208839 30218796

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Feb 2, 6:52 PM CST	Tornado Watch	SPC	Baldwin, Choctaw, Clarke, Mobile, Monroe, Washington and 1 more	8 hr
Feb 2, 8:50 PM CST	Mesoscale Discussion	SPC	Bibb, Blount, Chilton, Colbert, Cullman, Fayette and 22 more	55 min
Feb 2, 9:59 PM CST	Tornado Watch	SPC	Autauga, Bibb, Chilton, Clay, Coosa, Dallas and 14 more	6 hr
Feb 3, 1:30 AM CST	Mesoscale Discussion	SPC	Calhoun, Clay, Coosa, Elmore, Macon, Talladega and 1 more	60 min
Feb 2, 6:13 PM CST	Mesoscale Discussion	SPC	Alcorn, Attala, Benton, Bolivar, Calhoun, Carroll and 30 more	2 hr

Nearby

Mesoscale Discussions in Mississippi, 2016 Mesoscale Discussions in Alabama, 2016 Mesoscale Discussions in Louisiana, 2016 Every 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.