Alert archive / Mississippi / Mesoscale Discussions in 2009

Mesoscale Discussion 723

May 6, 200910 counties in Alabama; 24 counties in Arkansas; 30 counties in Mississippi

The Storm Prediction Center issued this mesoscale discussion at May 6, 2009, 1:27 AM CDT for 10 counties in Alabama; 24 counties in Arkansas; 30 counties in Mississippi. It was in force for 3 hr.

The area

The outline as issued.

The facts

Issued
May 6, 2009, 1:27 AM CDT (06:27 UTC)
Expired
May 6, 2009, 4:30 AM CDT
In force
3 hr
Issued by
the Storm Prediction Center
All 64 counties

Blount County, AL, Cullman County, AL, Fayette County, AL, Franklin County, AL, Jefferson County, AL, Lamar County, AL, Lawrence County, AL, Marion County, AL, Walker County, AL, Winston County, AL, Arkansas County, AR, Clark County, AR, Cleveland County, AR, Dallas County, AR, Desha County, AR, Faulkner County, AR, Garland County, AR, Grant County, AR, Hot Spring County, AR, Jefferson County, AR, Lee County, AR, Lincoln County, AR, Lonoke County, AR, Monroe County, AR, Montgomery County, AR, Perry County, AR, Phillips County, AR, Pike County, AR, Polk County, AR, Prairie County, AR, Pulaski County, AR, Saline County, AR, St. Francis County, AR, Yell County, AR, Benton County, MS, Bolivar County, MS, Calhoun County, MS, Chickasaw County, MS, Clay County, MS, Coahoma County, MS, DeSoto County, MS, Grenada County, MS, Itawamba County, MS, Lafayette County, MS, Lee County, MS, Leflore County, MS, Lowndes County, MS, Marshall County, MS, Monroe County, MS, Montgomery County, MS, Oktibbeha County, MS, Panola County, MS, Pontotoc County, MS, Prentiss County, MS, Quitman County, MS, Sunflower County, MS, Tallahatchie County, MS, Tate County, MS, Tippah County, MS, Tishomingo County, MS, Tunica County, MS, Union County, MS, Webster County, MS, Yalobusha County, MS

The radar

The Columbus AFB radar (KGWX), 82 km from the middle of the area, began a volume at 06:28 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 (KLZK), launched 00:00Z, 6.5 hours before the alert went out and 106 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 00:00Z on 2009-05-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3 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, Little Rock, AR at 00:00Z on 2009-05-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 61 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
3 J/kg
Mixed-layer CIN
-164 J/kg
Mixed-layer LCL
617 m above ground
0-6 km bulk shear
37 kt
0-1 km storm-relative helicity
61 m²/s²
0-3 km storm-relative helicity
89 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.

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SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 5, 11:45 PM CDTMesoscale DiscussionSPCBlount, Calhoun, Colbert, Cullman, Etowah, Fayette and 13 more90 min
May 6, 3:05 AM CDTMesoscale DiscussionSPCFayette, Jefferson, Lamar, Marion, Pickens, Tuscaloosa and 1 more115 min
May 6, 4:03 AM CDTSevere Thunderstorm WatchSPCBibb, Blount, Calhoun, Cherokee, Clay, Cleburne and 27 more6 hr
May 6, 6:58 AM CDTMesoscale DiscussionSPCGreene, Pickens, Sumter3 hr
May 6, 7:22 AM CDTMesoscale DiscussionSPCBibb, Blount, Calhoun, Cherokee, Chilton, Clay and 28 more83 min
May 6, 9:04 AM CDTMesoscale DiscussionSPCAutauga, Bibb, Blount, Bullock, Butler, Calhoun and 27 more56 min
May 6, 9:27 AM CDTTornado WatchSPCAutauga, Barbour, Bibb, Blount, Bullock, Calhoun and 31 more9 hr
May 6, 12:37 PM CDTSevere Thunderstorm WatchSPCButler, Choctaw, Clarke, Conecuh, Covington, Crenshaw and 4 more6 hr
May 6, 1:57 PM CDTMesoscale DiscussionSPCBullock, Russell93 min
May 6, 4:47 PM CDTMesoscale DiscussionSPCDale, Geneva, Henry58 min
May 5, 10:07 PM CDTMesoscale DiscussionSPCArkansas, Calhoun, Clark, Cleveland, Conway, Crittenden and 28 more83 min
May 5, 10:27 PM CDTSevere Thunderstorm WatchSPCArkansas, Ashley, Bradley, Calhoun, Chicot, Clark and 49 more8 hr
May 5, 11:26 PM CDTSevere Thunderstorm WatchSPCSebastian6 hr
May 6, 12:53 AM CDTMesoscale DiscussionSPCArkansas, Bradley, Calhoun, Clark, Cleveland, Dallas and 14 more37 min
May 6, 12:54 AM CDTTornado WatchSPCArkansas, Ashley, Bradley, Calhoun, Chicot, Clark and 20 more5 hr
May 6, 2:00 AM CDTMesoscale DiscussionSPCSebastian2 hr
May 6, 2:26 AM CDTMesoscale DiscussionSPCCleburne, Conway, Craighead, Crittenden, Cross, Faulkner and 23 more2 hr
May 6, 5:29 AM CDTSevere Thunderstorm WatchSPCColumbia, Hempstead, Howard, Lafayette, Little River, Miller and 3 more8 hr
May 6, 5:45 AM CDTSevere Thunderstorm WatchSPCAshley, Bradley, Calhoun, Chicot, Cleveland, Desha and 3 more7 hr
May 6, 11:34 AM CDTMesoscale DiscussionSPCAdams, Claiborne, Copiah, Covington, Franklin, Hinds and 11 more86 min

Nearby

Mesoscale Discussions in Mississippi, 2009Mesoscale Discussions in Arkansas, 2009Mesoscale Discussions in Alabama, 2009Every mesoscale discussion in 2009

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.