Alert archive / Tennessee / Mesoscale Discussions in 2008

Mesoscale Discussion 549

April 4, 20085 states

The Storm Prediction Center issued this mesoscale discussion at Apr 4, 2008, 1:28 AM CDT for 5 states. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
Apr 4, 2008, 1:28 AM CDT (06:28 UTC)
Expired
Apr 4, 2008, 3:30 AM CDT
In force
2 hr
Issued by
the Storm Prediction Center
All 88 counties

Colbert County, AL, Lauderdale County, AL, Crittenden County, AR, Lee County, AR, Adair County, KY, Allen County, KY, Barren County, KY, Butler County, KY, Caldwell County, KY, Calloway County, KY, Christian County, KY, Cumberland County, KY, Edmonson County, KY, Green County, KY, Hart County, KY, Hopkins County, KY, Logan County, KY, Lyon County, KY, Marshall County, KY, Metcalfe County, KY, Monroe County, KY, Muhlenberg County, KY, Simpson County, KY, Taylor County, KY, Todd County, KY, Trigg County, KY, Warren County, KY, Alcorn County, MS, Benton County, MS, DeSoto County, MS, Lafayette County, MS, Marshall County, MS, Panola County, MS, Prentiss County, MS, Quitman County, MS, Tate County, MS, Tippah County, MS, Tishomingo County, MS, Tunica County, MS, Union County, MS, Bedford County, TN, Benton County, TN, Cannon County, TN, Carroll County, TN, Cheatham County, TN, Chester County, TN, Clay County, TN, Crockett County, TN, Davidson County, TN, Decatur County, TN, Dickson County, TN, Dyer County, TN, Fayette County, TN, Gibson County, TN, Giles County, TN, Hardeman County, TN, Hardin County, TN, Haywood County, TN, Henderson County, TN, Henry County, TN, Hickman County, TN, Houston County, TN, Humphreys County, TN, Jackson County, TN, Lauderdale County, TN, Lawrence County, TN, Lewis County, TN, Lincoln County, TN, Macon County, TN, Madison County, TN, Marshall County, TN, Maury County, TN, McNairy County, TN, Montgomery County, TN, Moore County, TN, Perry County, TN, Robertson County, TN, Rutherford County, TN, Shelby County, TN, Smith County, TN, Stewart County, TN, Sumner County, TN, Tipton County, TN, Trousdale County, TN, Wayne County, TN, Weakley County, TN, Williamson County, TN, Wilson County, TN

The radar

The Paducah radar (KPAH), 123 km from the middle of the area, began a volume at 06:31 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

Nashville Metro, TN (KBNA), launched 00:00Z, 6.5 hours before the alert went out and 164 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, Nashville Metro, TN at 00:00Z on 2008-04-04Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 17 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, Nashville Metro, TN at 00:00Z on 2008-04-04The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 304 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
17 J/kg
Mixed-layer CIN
-154 J/kg
Mixed-layer LCL
734 m above ground
0-6 km bulk shear
58 kt
0-1 km storm-relative helicity
304 m²/s²
0-3 km storm-relative helicity
378 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

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 4, 2:46 AM CDTSevere Thunderstorm WatchSPCColbert, Franklin, Lauderdale, Lawrence, Limestone8 hr
Apr 4, 5:16 AM CDTMesoscale DiscussionSPCColbert, Franklin, Lauderdale, Lawrence, Limestone89 min
Apr 4, 7:55 AM CDTMesoscale DiscussionSPCBlount, Colbert, Cullman, Fayette, Franklin, Greene and 16 more2 hr
Apr 4, 9:48 AM CDTTornado WatchSPCAutauga, Bibb, Blount, Chilton, Choctaw, Clarke and 18 more9 hr
Apr 4, 12:01 PM CDTMesoscale DiscussionSPCAutauga, Bibb, Chilton, Choctaw, Dallas, Greene and 5 more89 min
Apr 4, 12:33 PM CDTMesoscale DiscussionSPCChambers, Cleburne, Lee, Randolph87 min
Apr 4, 1:27 PM CDTTornado WatchSPCBarbour, Bullock, Calhoun, Chambers, Cherokee, Clay and 14 more9 hr
Apr 4, 3:17 PM CDTMesoscale DiscussionSPCAutauga, Bibb, Calhoun, Chambers, Chilton, Clay and 10 more88 min
Apr 4, 5:02 PM CDTMesoscale DiscussionSPCAutauga, Baldwin, Barbour, Bullock, Butler, Choctaw and 23 more88 min
Apr 4, 5:48 PM CDTTornado WatchSPCBaldwin, Butler, Choctaw, Clarke, Coffee, Conecuh and 11 more6 hr
Apr 3, 7:59 PM CDTMesoscale DiscussionSPCBaxter, Benton, Boone, Calhoun, Carroll, Clark and 46 more91 min
Apr 3, 8:21 PM CDTSevere Thunderstorm WatchSPCArkansas, Baxter, Benton, Boone, Calhoun, Carroll and 52 more8 hr
Apr 3, 9:49 PM CDTMesoscale DiscussionSPCArkansas, Baxter, Boone, Clark, Clay, Cleburne and 55 more86 min
Apr 3, 10:23 PM CDTSevere Thunderstorm WatchSPCClay, Craighead, Crittenden, Cross, Greene, Lawrence and 6 more4 hr
Apr 3, 11:19 PM CDTMesoscale DiscussionSPCArkansas, Calhoun, Clark, Clay, Cleburne, Cleveland and 45 more86 min
Apr 4, 12:48 AM CDTMesoscale DiscussionSPCBradley, Calhoun, Columbia, Hempstead, Lafayette, Little River and 4 more117 min
Apr 4, 3:34 AM CDTMesoscale DiscussionSPCArkansas, Ashley, Bradley, Calhoun, Chicot, Clark and 15 more56 min
Apr 4, 3:55 AM CDTSevere Thunderstorm WatchSPCArkansas, Ashley, Bradley, Calhoun, Chicot, Clark and 19 more7 hr

Nearby

Mesoscale Discussions in Tennessee, 2008Mesoscale Discussions in Kentucky, 2008Mesoscale Discussions in Mississippi, 2008Every mesoscale discussion in 2008

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.