Alert archive / Tennessee / Mesoscale Discussions in 2017
Mesoscale Discussion 617
The Storm Prediction Center issued this mesoscale discussion at Apr 30, 2017, 3:42 PM CDT for 14 counties in Alabama; 15 counties in Georgia; 21 counties in Tennessee. It was in force for 2 hr.
The area
The outline as issued.
The facts
- Issued
- Apr 30, 2017, 3:42 PM CDT (20:42 UTC)
- Expired
- Apr 30, 2017, 5:45 PM CDT
- In force
- 2 hr
- Issued by
- the Storm Prediction Center
All 50 counties
Autauga County, AL, Calhoun County, AL, Chambers County, AL, Cherokee County, AL, Clay County, AL, Cleburne County, AL, Coosa County, AL, DeKalb County, AL, Elmore County, AL, Jackson County, AL, Lowndes County, AL, Randolph County, AL, Talladega County, AL, Tallapoosa County, AL, Bartow County, GA, Carroll County, GA, Catoosa County, GA, Chattooga County, GA, Dade 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, Bledsoe County, TN, Bradley County, TN, Cannon County, TN, Coffee County, TN, Cumberland County, TN, DeKalb County, TN, Fentress County, TN, Franklin County, TN, Grundy County, TN, Hamilton County, TN, Jackson County, TN, Marion County, TN, Meigs County, TN, Overton County, TN, Putnam County, TN, Rhea County, TN, Sequatchie County, TN, Smith County, TN, Van Buren County, TN, Warren County, TN, White County, TN
The radar
The Northeast Alabama radar (KHTX), 56 km from the middle of the area, began a volume at 20:45 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
Birmingham, AL (KBMX), launched 12:00Z, 8.7 hours before the alert went out and 183 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.
- Mixed-layer CAPE
- 53 J/kg
- Mixed-layer CIN
- -333 J/kg
- Mixed-layer LCL
- 867 m above ground
- 0-6 km bulk shear
- 22 kt
- 0-1 km storm-relative helicity
- 32 m²/s²
- 0-3 km storm-relative helicity
- 224 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
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</html>SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 30, 10:06 AM CDT | Mesoscale Discussion | SPC | Autauga, Bibb, Chilton, Colbert, Coosa, Cullman and 16 more | 84 min |
| Apr 30, 10:36 AM CDT | Tornado Watch | SPC | Autauga, Baldwin, Bibb, Blount, Chilton, Choctaw and 27 more | 8 hr |
| Apr 30, 1:21 PM CDT | Mesoscale Discussion | SPC | Cherokee, Cleburne, DeKalb, Etowah, Jackson, Madison and 1 more | 54 min |
| Apr 30, 1:36 PM CDT | Tornado Watch | SPC | Calhoun, Chambers, Cherokee, Clay, Cleburne, Coosa and 10 more | 5 hr |
| Apr 30, 12:54 AM CDT | Mesoscale Discussion | SPC | Crockett, Dyer, Fayette, Gibson, Haywood, Lake and 5 more | 96 min |
| Apr 30, 1:10 AM CDT | Severe Thunderstorm Watch | SPC | Benton, Carroll, Crockett, Decatur, Dyer, Gibson and 10 more | 6 hr |
| Apr 30, 2:58 AM CDT | Mesoscale Discussion | SPC | Benton, Carroll, Chester, Crockett, Dyer, Fayette and 13 more | 92 min |
| Apr 30, 5:41 AM CDT | Mesoscale Discussion | SPC | Benton, Carroll, Chester, Crockett, Decatur, Dyer and 11 more | 64 min |
Nearby
Mesoscale Discussions in Tennessee, 2017Mesoscale Discussions in Georgia, 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.