Alert archive / Tennessee / Mesoscale Discussions in 2003

Mesoscale Discussion 120

February 21, 20036 states

The Storm Prediction Center issued this mesoscale discussion at Feb 21, 2003, 11:14 PM CST for 6 states. It was in force for 4 hr.

The area

The outline as issued.

The facts

Issued
Feb 21, 2003, 11:14 PM CST (05:14 UTC)
Expired
Feb 22, 2003, 3:15 AM CST
In force
4 hr
Issued by
the Storm Prediction Center
All 91 counties

Blount County, AL, Calhoun County, AL, Cherokee County, AL, Cleburne County, AL, Cullman County, AL, DeKalb County, AL, Etowah County, AL, Fayette County, AL, Jackson County, AL, Jefferson County, AL, Lawrence County, AL, Limestone County, AL, Madison County, AL, Marshall County, AL, Morgan County, AL, Pickens County, AL, Shelby County, AL, St. Clair County, AL, Talladega County, AL, Tuscaloosa County, AL, Walker County, AL, Winston County, AL, Bartow County, GA, Catoosa County, GA, Chattooga County, GA, Dade County, GA, Fannin County, GA, Floyd County, GA, Gilmer County, GA, Gordon County, GA, Haralson County, GA, Murray County, GA, Polk County, GA, Walker County, GA, Whitfield County, GA, Bienville Parish, LA, Bossier Parish, LA, Caddo Parish, LA, Catahoula Parish, LA, De Soto Parish, LA, Grant Parish, LA, LaSalle Parish, LA, Natchitoches Parish, LA, Rapides Parish, LA, Red River Parish, LA, Tensas Parish, LA, Webster Parish, LA, Claiborne County, MS, Hinds County, MS, Leake County, MS, Neshoba County, MS, Noxubee County, MS, Anderson County, TN, Bedford County, TN, Bledsoe County, TN, Blount County, TN, Bradley County, TN, Cannon County, TN, Coffee County, TN, Cumberland County, TN, DeKalb County, TN, Franklin County, TN, Giles County, TN, Grainger County, TN, Grundy County, TN, Hamilton County, TN, Knox County, TN, Lincoln County, TN, Loudon County, TN, Marion County, TN, Marshall County, TN, McMinn County, TN, Meigs County, TN, Monroe County, TN, Moore County, TN, Morgan County, TN, Polk County, TN, Rhea County, TN, Roane County, TN, Sequatchie County, TN, Van Buren County, TN, Warren County, TN, White County, TN, Cherokee County, TX, Gregg County, TX, Harrison County, TX, Marion County, TX, Nacogdoches County, TX, Panola County, TX, Rusk County, TX, Shelby County, TX

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 00:00Z, 5.2 hours before the alert went out and 91 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 00:00Z on 2003-02-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 00:00Z on 2003-02-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 164 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
589 m above ground
0-6 km bulk shear
64 kt
0-1 km storm-relative helicity
164 m²/s²
0-3 km storm-relative helicity
289 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
Feb 21, 7:26 PM CSTMesoscale DiscussionSPCBaldwin, Clarke, Mobile, Washington2 hr
Feb 21, 8:15 PM CSTTornado WatchSPCBaldwin, Butler, Clarke, Conecuh, Covington, Crenshaw and 4 more6 hr
Feb 21, 9:03 PM CSTMesoscale DiscussionSPCAutauga, Bibb, Blount, Chilton, Choctaw, Coosa and 22 more3 hr
Feb 21, 9:30 PM CSTSevere Thunderstorm WatchSPCAutauga, Bibb, Calhoun, Chilton, Choctaw, Clay and 20 more7 hr
Feb 21, 10:22 PM CSTMesoscale DiscussionSPCBaldwin, Butler, Clarke, Conecuh, Covington, Crenshaw and 4 more113 min
Feb 21, 10:40 PM CSTMesoscale DiscussionSPCAutauga, Bibb, Calhoun, Chilton, Choctaw, Clay and 20 more2 hr
Feb 21, 11:40 PM CSTTornado WatchSPCBarbour, Bullock, Coffee, Dale, Geneva, Henry and 5 more6 hr
Feb 22, 12:35 AM CSTTornado WatchSPCAutauga, Baldwin, Bibb, Bullock, Butler, Calhoun and 37 more5 hr
Feb 22, 2:47 AM CSTMesoscale DiscussionSPCCalhoun, Cherokee, Cleburne, DeKalb, Etowah, Jackson and 4 more3 hr
Feb 22, 3:35 AM CSTTornado WatchSPCBlount, Calhoun, Chambers, Cherokee, Chilton, Clay and 12 more2 hr
Feb 22, 3:51 AM CSTMesoscale DiscussionSPCAutauga, Baldwin, Barbour, Bibb, Bullock, Butler and 43 more114 min
Feb 22, 5:19 AM CSTMesoscale DiscussionSPCBarbour, Henry, Houston, Russell56 min
Feb 22, 5:50 AM CSTTornado WatchSPCHenry, Houston5 hr
Feb 22, 9:14 AM CSTMesoscale DiscussionSPCDeKalb, Jackson, Marshall2 hr
Feb 22, 10:35 AM CSTTornado WatchSPCDeKalb, Jackson5 hr
Feb 21, 6:18 PM CSTMesoscale DiscussionSPCAppling, Atkinson, Bacon, Ben Hill, Berrien, Brantley and 20 more3 hr
Feb 22, 9:59 AM CSTMesoscale DiscussionSPCAppling, Brantley, Bryan, Bulloch, Camden, Charlton and 12 more61 min
Feb 22, 10:55 AM CSTTornado WatchSPCBrantley, Bryan, Bulloch, Camden, Charlton, Chatham and 9 more5 hr
Feb 22, 12:33 PM CSTMesoscale DiscussionSPCCatoosa, Colquitt, Dade, Lee, Murray, Schley and 3 more117 min
Feb 22, 12:49 PM CSTMesoscale DiscussionSPCCamden, Chatham, Glynn, McIntosh116 min
Feb 22, 2:31 PM CSTMesoscale DiscussionSPCCatoosa, Murray, Walker, Whitfield119 min
Feb 21, 10:54 PM CSTMesoscale DiscussionSPCBeauregard, Bienville, Bossier, Caddo, De Soto, Natchitoches and 4 more3 hr
Feb 22, 2:02 AM CSTMesoscale DiscussionSPCCaldwell, Catahoula, Concordia, East Carroll, Franklin, LaSalle and 6 more3 hr

Nearby

Mesoscale Discussions in Tennessee, 2003Mesoscale Discussions in Alabama, 2003Mesoscale Discussions in Georgia, 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.