Alert archive / Mississippi / Mesoscale Discussions in 2014

Mesoscale Discussion 450

April 28, 20144 states

The Storm Prediction Center issued this mesoscale discussion at Apr 28, 2014, 9:53 AM CDT for 4 states. It was in force for 97 min.

The area

The outline as issued.

The facts

Issued
Apr 28, 2014, 9:53 AM CDT (14:53 UTC)
Expired
Apr 28, 2014, 11:30 AM CDT
In force
97 min
Issued by
the Storm Prediction Center
All 66 counties

Fayette County, AL, Lamar County, AL, Marion County, AL, Pickens County, AL, Chicot County, AR, Caldwell Parish, LA, Catahoula Parish, LA, Concordia Parish, LA, East Carroll Parish, LA, Franklin Parish, LA, Grant Parish, LA, Jackson Parish, LA, LaSalle Parish, LA, Madison Parish, LA, Morehouse Parish, LA, Ouachita Parish, LA, Richland Parish, LA, Tensas Parish, LA, West Carroll Parish, LA, Winn Parish, LA, Adams County, MS, Amite County, MS, Attala County, MS, Calhoun County, MS, Carroll County, MS, Chickasaw County, MS, Choctaw County, MS, Claiborne County, MS, Clay County, MS, Copiah County, MS, Franklin County, MS, Grenada County, MS, Hinds County, MS, Holmes County, MS, Humphreys County, MS, Issaquena County, MS, Itawamba County, MS, Jefferson County, MS, Kemper County, MS, Lawrence County, MS, Leake County, MS, Lee County, MS, Leflore County, MS, Lincoln County, MS, Lowndes County, MS, Madison County, MS, Monroe County, MS, Montgomery County, MS, Neshoba County, MS, Newton County, MS, Noxubee County, MS, Oktibbeha County, MS, Pontotoc County, MS, Rankin County, MS, Scott County, MS, Sharkey County, MS, Simpson County, MS, Smith County, MS, Sunflower County, MS, Warren County, MS, Washington County, MS, Webster County, MS, Wilkinson County, MS, Winston County, MS, Yalobusha County, MS, Yazoo County, MS

The radar

The Jackson/Brandon,MS radar (KDGX), 42 km from the middle of the area, began a volume at 14:54 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

Jackson, MS (KJAN), launched 12:00Z, 2.9 hours before the alert went out and 33 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, Jackson, MS at 12:00Z on 2014-04-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1444 joules per kilogram.LCLLFCEL10008507005003002001001 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, Jackson, MS at 12:00Z on 2014-04-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 366 square meters per square second.19395878Sfc1 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
1444 J/kg
Mixed-layer CIN
-224 J/kg
Mixed-layer LCL
640 m above ground
0-6 km bulk shear
40 kt
0-1 km storm-relative helicity
366 m²/s²
0-3 km storm-relative helicity
543 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.7

Open this sounding in Storm Lab

The text

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

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SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 28, 6:57 AM CDTMesoscale DiscussionSPCLauderdale2 hr
Apr 28, 12:05 PM CDTMesoscale DiscussionSPCColbert, Fayette, Franklin, Lamar, Lauderdale, Lawrence and 6 more115 min
Apr 28, 12:39 PM CDTTornado Watch PDSSPCColbert, Cullman, DeKalb, Fayette, Franklin, Greene and 14 more8 hr
Apr 28, 2:09 PM CDTMesoscale DiscussionSPCBlount, Colbert, Cullman, Fayette, Franklin, Jackson and 13 more66 min
Apr 28, 3:49 PM CDTMesoscale DiscussionSPCColbert, Franklin, Lamar, Lawrence, Limestone, Marion and 1 more86 min
Apr 28, 5:22 PM CDTMesoscale DiscussionSPCColbert, Cullman, Fayette, Franklin, Jackson, Lamar and 9 more83 min
Apr 28, 5:56 PM CDTMesoscale DiscussionSPCAutauga, Bibb, Calhoun, Chambers, Cherokee, Chilton and 13 more64 min
Apr 27, 7:15 PM CDTMesoscale DiscussionSPCFaulkner30 min
Apr 27, 7:29 PM CDTMesoscale DiscussionSPCClay, Craighead, Crittenden, Cross, Greene, Mississippi and 1 more91 min
Apr 27, 7:53 PM CDTTornado WatchSPCClay, Craighead, Crittenden, Cross, Greene, Lawrence and 4 more6 hr
Apr 27, 8:09 PM CDTMesoscale DiscussionSPCColumbia, Lafayette, Miller, Union66 min
Apr 27, 8:43 PM CDTMesoscale DiscussionSPCClark, Clay, Cleburne, Cleveland, Conway, Craighead and 45 more62 min
Apr 27, 9:59 PM CDTMesoscale DiscussionSPCCalhoun, Clark, Cleburne, Cleveland, Columbia, Conway and 36 more91 min
Apr 27, 10:33 PM CDTTornado WatchSPCArkansas, Bradley, Calhoun, Clark, Cleveland, Conway and 27 more7 hr
Apr 27, 11:08 PM CDTTornado WatchSPCColumbia, Hempstead, Howard, Lafayette, Little River, Miller and 3 more6 hr
Apr 27, 11:21 PM CDTMesoscale DiscussionSPCArkansas, Baxter, Boone, Bradley, Calhoun, Carroll and 38 more84 min
Apr 27, 11:41 PM CDTMesoscale DiscussionSPCClay, Craighead, Crittenden, Cross, Greene, Mississippi and 2 more94 min
Apr 28, 1:43 AM CDTTornado WatchSPCClay, Craighead, Crittenden, Cross, Greene, Lawrence and 6 more8 hr
Apr 28, 2:50 AM CDTMesoscale DiscussionSPCArkansas, Ashley, Bradley, Calhoun, Chicot, Cleveland and 25 more115 min
Apr 28, 4:21 AM CDTMesoscale DiscussionSPCAshley, Bradley, Chicot, Columbia, Drew, Union54 min
Apr 28, 4:40 AM CDTTornado WatchSPCAshley, Chicot, Union7 hr
Apr 28, 7:16 AM CDTMesoscale DiscussionSPCChicot89 min
Apr 27, 10:45 PM CDTMesoscale DiscussionSPCBossier, Caddo, De Soto, Sabine2 hr
Apr 28, 3:55 PM CDTMesoscale DiscussionSPCAllen, Beauregard, Evangeline, Jefferson Davis, Rapides, Vernon2 hr
Apr 27, 7:03 PM CDTMesoscale DiscussionSPCCalhoun, Chickasaw, Clay, Grenada, Itawamba, Lafayette and 10 more87 min

Nearby

Mesoscale Discussions in Mississippi, 2014Mesoscale Discussions in Louisiana, 2014Mesoscale Discussions in Alabama, 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.