Alert archive / Tennessee / Mesoscale Discussions in 2017

Mesoscale Discussion 448

April 5, 20174 states

The Storm Prediction Center issued this mesoscale discussion at Apr 5, 2017, 3:51 PM CDT for 4 states. It was in force for 84 min.

The area

The outline as issued.

The facts

Issued
Apr 5, 2017, 3:51 PM CDT (20:51 UTC)
Expired
Apr 5, 2017, 5:15 PM CDT
In force
84 min
Issued by
the Storm Prediction Center
All 124 counties

Blount County, AL, Calhoun County, AL, Chambers County, AL, Cherokee County, AL, Chilton County, AL, Clay County, AL, Cleburne County, AL, Coosa County, AL, Cullman County, AL, DeKalb County, AL, Elmore County, AL, Etowah County, AL, Jackson County, AL, Jefferson County, AL, Lee County, AL, Limestone County, AL, Macon County, AL, Madison County, AL, Marshall County, AL, Morgan County, AL, Randolph County, AL, Shelby County, AL, St. Clair County, AL, Talladega County, AL, Tallapoosa County, AL, Bartow County, GA, Carroll County, GA, Catoosa County, GA, Chattooga County, GA, Dade County, GA, Douglas County, GA, Floyd County, GA, Gordon County, GA, Haralson County, GA, Heard County, GA, Murray County, GA, Paulding County, GA, Polk County, GA, Troup County, GA, Walker County, GA, Whitfield County, GA, Adair County, KY, Allen County, KY, Anderson County, KY, Barren County, KY, Boyle County, KY, Breckinridge County, KY, Bullitt County, KY, Butler County, KY, Casey County, KY, Clinton County, KY, Cumberland County, KY, Edmonson County, KY, Franklin County, KY, Garrard County, KY, Grayson County, KY, Green County, KY, Hardin County, KY, Hart County, KY, Jefferson County, KY, Jessamine County, KY, Larue County, KY, Lincoln County, KY, Madison County, KY, Marion County, KY, McCreary County, KY, Meade County, KY, Mercer County, KY, Metcalfe County, KY, Monroe County, KY, Nelson County, KY, Pulaski County, KY, Rockcastle County, KY, Russell County, KY, Shelby County, KY, Simpson County, KY, Spencer County, KY, Taylor County, KY, Warren County, KY, Washington County, KY, Wayne County, KY, Woodford County, KY, Bedford County, TN, Bledsoe County, TN, Bradley County, TN, Cannon County, TN, Clay County, TN, Coffee County, TN, Cumberland County, TN, Davidson County, TN, DeKalb County, TN, Fentress County, TN, Franklin County, TN, Giles County, TN, Grundy County, TN, Hamilton County, TN, Jackson County, TN, Lincoln County, TN, Macon County, TN, Marion County, TN, Marshall County, TN, Maury County, TN, McMinn County, TN, Meigs County, TN, Moore County, TN, Morgan County, TN, Overton County, TN, Pickett County, TN, Polk County, TN, Putnam County, TN, Rhea County, TN, Roane County, TN, Robertson County, TN, Rutherford County, TN, Scott County, TN, Sequatchie County, TN, Smith County, TN, Sumner County, TN, Trousdale County, TN, Van Buren County, TN, Warren County, TN, White County, TN, Williamson County, TN, Wilson County, TN

The radar

The Northeast Alabama radar (KHTX), 47 km from the middle of the area, began a volume at 20:55 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 nearest sounding before it

Nashville Metro, TN (KBNA), launched 12:00Z, 8.9 hours before the alert went out and 140 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 12:00Z on 2017-04-05Temperature 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, Nashville Metro, TN at 12:00Z on 2017-04-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 161 square meters per square second.1939587897Sfc1 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
1902 m above ground
0-6 km bulk shear
57 kt
0-1 km storm-relative helicity
161 m²/s²
0-3 km storm-relative helicity
208 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

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SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 4, 11:54 PM CDTMesoscale DiscussionSPCBaldwin, Butler, Clarke, Coffee, Conecuh, Covington and 8 more2 hr
Apr 5, 1:37 AM CDTSevere Thunderstorm WatchSPCAutauga, Barbour, Bibb, Blount, Bullock, Butler and 42 more6 hr
Apr 5, 3:41 AM CDTMesoscale DiscussionSPCAutauga, Barbour, Bibb, Bullock, Butler, Chambers and 38 more2 hr
Apr 5, 6:15 AM CDTMesoscale DiscussionSPCAutauga, Barbour, Bibb, Bullock, Butler, Calhoun and 35 more90 min
Apr 5, 6:54 AM CDTTornado WatchSPCAutauga, Baldwin, Barbour, Bibb, Bullock, Butler and 44 more8 hr
Apr 5, 9:43 AM CDTMesoscale DiscussionSPCBarbour, Chambers, Lee, Macon, Russell, Tallapoosa2 hr
Apr 5, 11:54 AM CDTTornado Watch PDSSPCDale, Geneva, Henry, Houston10 hr
Apr 5, 1:02 PM CDTMesoscale DiscussionSPCBlount, Cullman, DeKalb, Jackson, Jefferson, Lauderdale and 8 more2 hr
Apr 5, 1:50 PM CDTTornado WatchSPCAutauga, Barbour, Bibb, Blount, Bullock, Calhoun and 36 more8 hr
Apr 5, 2:12 PM CDTMesoscale DiscussionSPCBarbour, Bullock, Dale, Henry, Houston, Lee and 2 more93 min
Apr 5, 3:29 PM CDTMesoscale DiscussionSPCBaldwin, Clarke, Conecuh, Escambia, Marengo, Mobile and 3 more3 hr
Apr 5, 6:57 PM CDTMesoscale DiscussionSPCAutauga, Blount, Bullock, Calhoun, Chambers, Cherokee and 20 more48 min
Apr 5, 9:25 AM CDTMesoscale DiscussionSPCBaldwin, Banks, Barrow, Bartow, Burke, Butts and 45 more95 min
Apr 5, 10:38 AM CDTMesoscale DiscussionSPCAppling, Atkinson, Bacon, Baker, Ben Hill, Berrien and 52 more97 min
Apr 5, 5:29 PM CDTMesoscale DiscussionSPCAppling, Atkinson, Bacon, Berrien, Brantley, Brooks and 22 more61 min
Apr 5, 1:59 PM CDTMesoscale DiscussionSPCBoone, Bracken, Campbell, Carroll, Gallatin, Grant and 11 more3 hr
Apr 5, 3:08 PM CDTSevere Thunderstorm WatchSPCBoone, Bracken, Campbell, Carroll, Daviess, Gallatin and 9 more5 hr
Apr 5, 4:47 PM CDTMesoscale DiscussionSPCCampbell, Kenton88 min
Apr 5, 6:19 PM CDTMesoscale DiscussionSPCBoyd, Carter, Elliott, Floyd, Greenup, Johnson and 8 more2 hr

Nearby

Mesoscale Discussions in Tennessee, 2017Mesoscale Discussions in Kentucky, 2017Mesoscale Discussions in Alabama, 2017Every mesoscale discussion in 2017

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.