Alert archive / Arkansas / Mesoscale Discussions in 2003

Mesoscale Discussion 813

May 7, 20036 states

The Storm Prediction Center issued this mesoscale discussion at May 7, 2003, 2:27 AM CDT for 6 states. It was in force for 3 hr.

The area

The outline as issued.

The facts

Issued
May 7, 2003, 2:27 AM CDT (07:27 UTC)
Expired
May 7, 2003, 5:00 AM CDT
In force
3 hr
Issued by
the Storm Prediction Center
All 155 counties

Arkansas County, AR, Ashley County, AR, Baxter County, AR, Boone County, AR, Bradley County, AR, Calhoun County, AR, Chicot County, AR, Clark County, AR, Clay County, AR, Cleburne County, AR, Cleveland County, AR, Columbia County, AR, Conway County, AR, Craighead County, AR, Crittenden County, AR, Cross County, AR, Dallas County, AR, Desha County, AR, Drew County, AR, Faulkner County, AR, Franklin County, AR, Fulton County, AR, Garland County, AR, Grant County, AR, Greene County, AR, Hempstead County, AR, Hot Spring County, AR, Howard County, AR, Independence County, AR, Izard County, AR, Jackson County, AR, Jefferson County, AR, Johnson County, AR, Lafayette County, AR, Lawrence County, AR, Lee County, AR, Lincoln County, AR, Little River County, AR, Logan County, AR, Lonoke County, AR, Marion County, AR, Miller County, AR, Mississippi County, AR, Monroe County, AR, Montgomery County, AR, Nevada County, AR, Newton County, AR, Ouachita County, AR, Perry County, AR, Phillips County, AR, Pike County, AR, Poinsett County, AR, Polk County, AR, Pope County, AR, Prairie County, AR, Pulaski County, AR, Randolph County, AR, Saline County, AR, Scott County, AR, Searcy County, AR, Sebastian County, AR, Sevier County, AR, Sharp County, AR, St. Francis County, AR, Stone County, AR, Union County, AR, Van Buren County, AR, White County, AR, Woodruff County, AR, Yell County, AR, Bienville Parish, LA, Bossier Parish, LA, Caddo Parish, LA, Caldwell Parish, LA, Claiborne Parish, LA, De Soto Parish, LA, East Carroll Parish, LA, Franklin Parish, LA, Jackson Parish, LA, Lincoln Parish, LA, Madison Parish, LA, Morehouse Parish, LA, Ouachita Parish, LA, Red River Parish, LA, Richland Parish, LA, Union Parish, LA, Webster Parish, LA, West Carroll Parish, LA, Dunklin County, MO, Pemiscot County, MO, Attala County, MS, Bolivar County, MS, Calhoun County, MS, Carroll County, MS, Chickasaw County, MS, Choctaw County, MS, Clay County, MS, Coahoma County, MS, Grenada County, MS, Hinds County, MS, Holmes County, MS, Humphreys County, MS, Issaquena County, MS, Itawamba County, MS, Jasper County, MS, Lafayette County, MS, Leake County, MS, Lee County, MS, Leflore 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, Panola County, MS, Pontotoc County, MS, Quitman County, MS, Rankin County, MS, Scott County, MS, Sharkey County, MS, Smith County, MS, Sunflower County, MS, Tallahatchie County, MS, Warren County, MS, Washington County, MS, Webster County, MS, Winston County, MS, Yalobusha County, MS, Yazoo County, MS, McCurtain County, OK, Bowie County, TX, Camp County, TX, Cass County, TX, Delta County, TX, Franklin County, TX, Gregg County, TX, Harrison County, TX, Henderson County, TX, Hopkins County, TX, Kaufman County, TX, Lamar County, TX, Marion County, TX, Morris County, TX, Panola County, TX, Rains County, TX, Red River County, TX, Rusk County, TX, Smith County, TX, Titus County, TX, Upshur County, TX, Van Zandt County, TX, Wood County, TX

The radar

The Little Rock radar (KLZK), 121 km from the middle of the area, began a volume at 07:28 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

Shreveport, LA (KSHV), launched 00:00Z, 7.5 hours before the alert went out and 193 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, Shreveport, LA at 00:00Z on 2003-05-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2206 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, Shreveport, LA at 00:00Z on 2003-05-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 162 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
2206 J/kg
Mixed-layer CIN
-215 J/kg
Mixed-layer LCL
1131 m above ground
0-6 km bulk shear
60 kt
0-1 km storm-relative helicity
162 m²/s²
0-3 km storm-relative helicity
303 m²/s²
Significant tornado parameter
0.0
Supercell composite
11.5

Open this sounding in Storm Lab

The text

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

770 
ACUS11 KWNS 070727
SWOMCD
SPC MCD 070727 
MOZ000-TNZ000-ARZ000-MSZ000-LAZ000-TXZ000-OKZ000-ALZ000-071000-

MESOSCALE DISCUSSION 0813
NWS STORM PREDICTION CENTER NORMAN OK
0227 AM CDT WED MAY 07 2003

AREAS AFFECTED...NE TX...NRN LA...AR.

CONCERNING...SEVERE TSTM POTENTIAL...TORNADO WATCH 279...

VALID 070727Z - 071000Z

SEVERAL CLUSTERS OF SEVERE TSTMS -- INCLUDING A FEW SUPERCELLS --
WILL MOVE EWD ACROSS CENTRAL/ERN AR NEXT COUPLE HOURS. 
LARGE/PERSISTENT HEAVY-PRECIP SUPERCELL MOVING INTO NWRN
LA...BETWEEN SHV AND AR BORDER -- SHOULD CONTINUE RIGHT-MOVING EWD
ACROSS MUCH OF NRN TIER LA COUNTIES WITH POTENTIAL FOR
TORNADOES...DESTRUCTIVE HAIL AND SEVERE GUSTS.	PRESENT STORM
MOTIONS YIELDS UP TO 500 J/KG SRH IN 0-3 KM AGL LAYER FOR NRN LA. 
MODIFIED RAOB AND RUC SOUNDING SHOWS INCREASINGLY SHALLOW MOIST
LAYER WITH WWD EXTENT...HOWEVER CELLS ARE DEVELOPING ALONG COLD
FRONT AND BEHIND SUPERCELL...ACROSS PORTIONS NE TX...WITH POTENTIAL
FOR SEVERE.  2000-300 J/KG MUCAPE IS COMMON IN AREAS NOT ALREADY
WORKED OVER BY CONVECTION...ALONG WITH FAVORABLE VERTICAL SHEAR
PROFILES FOR BOTH SUPERCELLS AND DAMAGING BOW ECHOES.	

ACTIVITY IS GRADUALLY MERGING INTO LARGE MCS AND ADDITIONAL WW MAY
BE REQUIRED IN NEXT HOUR OR TWO FOR NRN MS.


..EDWARDS.. 05/07/2003

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

ATTN...WFO...PAH...MEG...JAN...LZK...SHV...TSA...FWD...BMX...HUN...

32059659 33999557 36439296 36408951 32049214 

32049214 34419072 34418812 32008893

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 6, 7:15 PM CDTSevere Thunderstorm WatchSPCAshley, Chicot5 hr
May 6, 7:53 PM CDTMesoscale DiscussionSPCBaxter, Cleburne, Conway, Faulkner, Fulton, Garland and 19 more2 hr
May 6, 11:08 PM CDTMesoscale DiscussionSPCArkansas, Bradley, Calhoun, Clark, Cleveland, Columbia and 33 more97 min
May 6, 11:30 PM CDTTornado WatchSPCArkansas, Ashley, Baxter, Boone, Bradley, Calhoun and 67 more6 hr
May 7, 4:55 AM CDTTornado WatchSPCArkansas, Ashley, Bradley, Chicot, Crittenden, Cross and 8 more6 hr
May 7, 7:06 AM CDTMesoscale DiscussionSPCAshley, Bradley, Chicot, Desha, Drew, Phillips and 1 more114 min
May 7, 10:50 AM CDTTornado WatchSPCAshley, Chicot, Drew5 hr
May 7, 1:54 PM CDTMesoscale DiscussionSPCChicot2 hr
May 6, 9:53 PM CDTMesoscale DiscussionSPCMadison97 min
May 7, 9:47 AM CDTMesoscale DiscussionSPCBienville, Caldwell, Catahoula, Concordia, East Carroll, Franklin and 14 more118 min
May 6, 11:50 PM CDTTornado WatchSPCAlcorn, Benton, DeSoto, Marshall, Prentiss, Tate and 4 more6 hr
May 7, 1:41 AM CDTMesoscale DiscussionSPCAlcorn, Benton, DeSoto, Marshall, Prentiss, Tate and 4 more3 hr
May 7, 7:35 AM CDTTornado WatchSPCKemper, Lauderdale, Lowndes, Monroe, Neshoba, Newton and 4 more5 hr
May 7, 1:42 PM CDTMesoscale DiscussionSPCClarke, Covington, Forrest, George, Greene, Harrison and 8 more2 hr
May 7, 3:00 PM CDTTornado WatchSPCLowndes6 hr
May 7, 6:29 PM CDTMesoscale DiscussionSPCClarke, Jasper, Lauderdale, Lowndes, Newton, Wayne91 min
May 6, 7:03 PM CDTMesoscale DiscussionSPCBollinger, Cape Girardeau, Iron, Jefferson, Madison, Perry and 4 more117 min
May 6, 9:35 PM CDTMesoscale DiscussionSPCBollinger, Cape Girardeau, Perry, Sainte Genevieve, Scott115 min
May 7, 5:00 PM CDTTornado WatchSPCBeckham, Caddo, Comanche, Cotton, Greer, Harmon and 4 more6 hr
May 6, 7:48 PM CDTMesoscale DiscussionSPCCollin, Cooke, Dallas, Denton, Erath, Fannin and 12 more117 min
May 7, 2:17 PM CDTMesoscale DiscussionSPCBorden, Coke, Concho, Dawson, Fisher, Garza and 19 more103 min
May 7, 5:38 PM CDTMesoscale DiscussionSPCArcher, Baylor, Callahan, Clay, Eastland, Fisher and 16 more97 min

Nearby

Mesoscale Discussions in Arkansas, 2003Mesoscale Discussions in Mississippi, 2003Mesoscale Discussions in Texas, 2003Every mesoscale discussion in 2003

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.