Alert archive / Mississippi / Mesoscale Discussions in 2014

Mesoscale Discussion 921

June 9, 20145 states

The Storm Prediction Center issued this mesoscale discussion at Jun 9, 2014, 1:54 PM CDT for 5 states. It was in force for 96 min.

The area

The outline as issued.

The facts

Issued
Jun 9, 2014, 1:54 PM CDT (18:54 UTC)
Expired
Jun 9, 2014, 3:30 PM CDT
In force
96 min
Issued by
the Storm Prediction Center
All 84 counties

Arkansas County, AR, Ashley County, AR, Bradley County, AR, Chicot County, AR, Craighead County, AR, Crittenden County, AR, Cross County, AR, Desha County, AR, Drew County, AR, Greene County, AR, Jackson County, AR, Lee County, AR, Lincoln County, AR, Mississippi County, AR, Monroe County, AR, Phillips County, AR, Poinsett County, AR, Prairie County, AR, St. Francis County, AR, Woodruff County, AR, Caldwell Parish, LA, East Carroll Parish, LA, Franklin Parish, LA, Jackson Parish, LA, Lincoln Parish, LA, Madison Parish, LA, Morehouse Parish, LA, Natchitoches Parish, LA, Ouachita Parish, LA, Richland Parish, LA, Tensas Parish, LA, Union Parish, LA, West Carroll Parish, LA, Winn Parish, LA, Dunklin County, MO, Pemiscot County, MO, Alcorn County, MS, Attala County, MS, Benton County, MS, Bolivar County, MS, Calhoun County, MS, Carroll County, MS, Coahoma County, MS, DeSoto County, MS, Grenada County, MS, Holmes County, MS, Humphreys County, MS, Issaquena County, MS, Lafayette County, MS, Leflore County, MS, Marshall County, MS, Montgomery County, MS, Panola County, MS, Pontotoc County, MS, Quitman County, MS, Sharkey County, MS, Sunflower County, MS, Tallahatchie County, MS, Tate County, MS, Tippah County, MS, Tunica County, MS, Union County, MS, Warren County, MS, Washington County, MS, Webster County, MS, Yalobusha County, MS, Yazoo County, MS, Carroll County, TN, Chester County, TN, Crockett County, TN, Dyer County, TN, Fayette County, TN, Gibson County, TN, Hardeman County, TN, Haywood County, TN, Henderson County, TN, Lake County, TN, Lauderdale County, TN, Madison County, TN, McNairy County, TN, Obion County, TN, Shelby County, TN, Tipton County, TN, Weakley County, TN

The radar

The Memphis radar (KNQA), 118 km from the middle of the area, began a volume at 18:57 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

Little Rock, AR (KBYH), launched 12:00Z, 6.9 hours before the alert went out and 72 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, Little Rock, AR at 12:00Z on 2014-06-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 40 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Little Rock, AR at 12:00Z on 2014-06-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 162 square meters per square second.193958Sfc1 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
40 J/kg
Mixed-layer CIN
-187 J/kg
Mixed-layer LCL
453 m above ground
0-6 km bulk shear
25 kt
0-1 km storm-relative helicity
162 m²/s²
0-3 km storm-relative helicity
136 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.

907 
ACUS11 KWNS 091855
SWOMCD
SPC MCD 091854 
TNZ000-MSZ000-MOZ000-ARZ000-LAZ000-092030-

MESOSCALE DISCUSSION 0921
NWS STORM PREDICTION CENTER NORMAN OK
0154 PM CDT MON JUN 09 2014

AREAS AFFECTED...NORTHERN LA AND SOUTHERN/EASTERN AR TO
WESTERN/NORTHERN MS AND WESTERN TN

CONCERNING...SEVERE THUNDERSTORM WATCH 267...

VALID 091854Z - 092030Z

THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 267
CONTINUES.

SUMMARY...THE POTENTIAL FOR DAMAGING WINDS AND SOME SEVERE
HAIL/POSSIBLY A TORNADO SHOULD INCREASE THROUGH MID/LATE AFTERNOON
ACROSS NORTHERN LA/EASTERN AR INTO WESTERN/NORTHERN MS AND WESTERN
TN. SEVERE THUNDERSTORM WATCH 267 CONTINUES UNTIL 00Z/7PM CDT. AN
WATCH COULD BE NEEDED WITHIN THE HOUR FOR ADDITIONAL PORTIONS OF
NORTHEAST AR/WESTERN TN.

DISCUSSION...A FRAGMENTED SQUALL LINE...EXTENDING FROM JUST EAST OF
THE LITTLE ROCK AREA INTO NORTH-CENTRAL/WEST-CENTRAL LA AS OF
1830Z...WILL CONTINUE A GENERAL EAST-NORTHEASTWARD PROGRESSION
THROUGH THE AFTERNOON. AT 18Z...A WEAK SURFACE LOW WAS NOTED NEAR
THE LITTLE ROCK AREA WITH PRECEDING PRESSURE FALLS AS FAR EAST AS
NORTHERN MS/WESTERN TN. A PRIOR OUTFLOW BOUNDARY ALONG THE AR/LA
BORDER INTO CENTRAL MS HAS LARGELY MODIFIED...WITH STEADY
WARMING/DESTABILIZATION CURRENTLY OCCURRING AS FAR NORTH AS
NORTHEAST AR/SOUTHWEST TN IN TANDEM WITH A NORTHWARD-MOVING WARM
FRONT. LATEST WSR-88D VWP DATA FROM LITTLE ROCK IN SAMPLING 50+ KT
SOUTHWESTERLY WINDS BETWEEN 2-6 KM IN THE IMMEDIATE WAKE OF THE
SQUALL LINE. ADDITIONAL BOUNDARY LAYER HEATING/MOISTENING...ALONG
WITH INCREASING INFLUENCES OF AN UPSTREAM UPPER LOW OVER THE
SOUTHERN PLAINS...WILL LIKELY INFLUENCE AN INCREASE IN QUASI-LINEAR
ORGANIZATION/INTENSITY OVER THE NEXT FEW HOURS.

..GUYER.. 06/09/2014

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

ATTN...WFO...PAH...MEG...JAN...LZK...SHV...

LAT...LON   35429145 36379031 36508871 35408816 33298930 31849109
            31689313 34329182 35429145

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 8, 7:47 PM CDTMesoscale DiscussionSPCAshley, Bradley, Calhoun, Chicot, Clark, Cleveland and 15 more88 min
Jun 8, 8:41 PM CDTSevere Thunderstorm WatchSPCArkansas, Ashley, Bradley, Calhoun, Chicot, Clark and 20 more7 hr
Jun 8, 10:53 PM CDTMesoscale DiscussionSPCArkansas, Ashley, Bradley, Calhoun, Chicot, Cleveland and 19 more97 min
Jun 9, 9:39 AM CDTMesoscale DiscussionSPCAshley, Bradley, Calhoun, Chicot, Clark, Cleveland and 11 more2 hr
Jun 9, 11:40 AM CDTSevere Thunderstorm WatchSPCArkansas, Ashley, Bradley, Calhoun, Chicot, Cleveland and 16 more7 hr
Jun 9, 2:14 PM CDTTornado WatchSPCClay, Craighead, Crittenden, Cross, Greene, Lee and 4 more5 hr
Jun 9, 3:22 PM CDTMesoscale DiscussionSPCChicot83 min
Jun 9, 3:43 PM CDTMesoscale DiscussionSPCCrittenden, Mississippi92 min
Jun 9, 12:07 PM CDTMesoscale DiscussionSPCAllen, Beauregard, Calcasieu, Vernon2 hr
Jun 8, 7:09 PM CDTMesoscale DiscussionSPCKemper, Lauderdale, Noxubee2 hr
Jun 9, 2:07 AM CDTMesoscale DiscussionSPCAlcorn, Benton, Calhoun, Chickasaw, Clay, Grenada and 24 more83 min
Jun 9, 4:54 PM CDTMesoscale DiscussionSPCAlcorn, Attala, Benton, Calhoun, Carroll, Chickasaw and 35 more96 min
Jun 9, 5:16 PM CDTSevere Thunderstorm WatchSPCChoctaw, Clarke, Clay, Covington, Jasper, Jefferson Davis and 15 more8 hr
Jun 9, 5:19 PM CDTMesoscale DiscussionSPCAlcorn, Benton, Calhoun, Chickasaw, Itawamba, Lafayette and 9 more26 min
Jun 9, 5:30 PM CDTTornado WatchSPCAlcorn, Benton, Calhoun, Chickasaw, Itawamba, Lafayette and 9 more8 hr
Jun 9, 6:55 PM CDTMesoscale DiscussionSPCAlcorn, Chickasaw, Clay, Itawamba, Lee, Lowndes and 7 more95 min

Nearby

Mesoscale Discussions in Mississippi, 2014Mesoscale Discussions in Arkansas, 2014Mesoscale Discussions in Tennessee, 2014Every mesoscale discussion in 2014

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.