Alert archive / Georgia / Mesoscale Discussions in 2018
Mesoscale Discussion 1122
The Storm Prediction Center issued this mesoscale discussion at Jul 21, 2018, 2:37 PM CDT for 5 states. It was in force for 2 hr.
The area
The outline as issued.
The facts
- Issued
- Jul 21, 2018, 2:37 PM CDT (19:37 UTC)
- Expired
- Jul 21, 2018, 5:00 PM CDT
- In force
- 2 hr
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 40%
All 87 counties
Cherokee County, AL, Cleburne County, AL, DeKalb County, AL, Randolph County, AL, Banks County, GA, Barrow County, GA, Bartow County, GA, Carroll County, GA, Catoosa County, GA, Chattooga County, GA, Cherokee County, GA, Clayton County, GA, Cobb County, GA, Coweta County, GA, Dade County, GA, Dawson County, GA, DeKalb County, GA, Douglas County, GA, Fannin County, GA, Fayette County, GA, Floyd County, GA, Forsyth County, GA, Franklin County, GA, Fulton County, GA, Gilmer County, GA, Gordon County, GA, Gwinnett County, GA, Habersham County, GA, Hall County, GA, Haralson County, GA, Harris County, GA, Hart County, GA, Heard County, GA, Henry County, GA, Jackson County, GA, Lumpkin County, GA, Madison County, GA, Meriwether County, GA, Murray County, GA, Newton County, GA, Paulding County, GA, Pickens County, GA, Pike County, GA, Polk County, GA, Rabun County, GA, Rockdale County, GA, Spalding County, GA, Stephens County, GA, Towns County, GA, Troup County, GA, Union County, GA, Walker County, GA, Walton County, GA, White County, GA, Whitfield County, GA, Buncombe County, NC, Cherokee County, NC, Clay County, NC, Graham County, NC, Haywood County, NC, Henderson County, NC, Jackson County, NC, Macon County, NC, Madison County, NC, Polk County, NC, Swain County, NC, Transylvania County, NC, Yancey County, NC, Greenville County, SC, Oconee County, SC, Pickens County, SC, Bledsoe County, TN, Blount County, TN, Bradley County, TN, Cocke County, TN, Hamilton County, TN, Jefferson County, TN, Knox County, TN, Loudon County, TN, McMinn County, TN, Meigs County, TN, Monroe County, TN, Polk County, TN, Rhea County, TN, Roane County, TN, Sequatchie County, TN, Sevier County, TN
The radar
The Greer radar (KGSP), 138 km from the middle of the area, began a volume at 19:41 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 12:00Z, 7.6 hours before the alert went out and 303 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
- 682 J/kg
- Mixed-layer CIN
- -150 J/kg
- Mixed-layer LCL
- 826 m above ground
- 0-6 km bulk shear
- 60 kt
- 0-1 km storm-relative helicity
- 137 m²/s²
- 0-3 km storm-relative helicity
- 240 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 10.6
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 |
|---|---|---|---|---|
| Jul 20, 10:20 PM CDT | Mesoscale Discussion | SPC | Colbert, Franklin, Lauderdale, Lawrence, Limestone, Madison and 1 more | 115 min |
| Jul 21, 1:38 AM CDT | Mesoscale Discussion | SPC | Blount, Colbert, Cullman, DeKalb, Etowah, Franklin and 10 more | 67 min |
| Jul 21, 2:00 AM CDT | Severe Thunderstorm Watch | SPC | Blount, Calhoun, Chambers, Cherokee, Clay, Cleburne and 10 more | 7 hr |
| Jul 21, 4:35 AM CDT | Mesoscale Discussion | SPC | Calhoun, Chambers, Cherokee, Clay, Cleburne, DeKalb and 6 more | 115 min |
| Jul 21, 7:10 AM CDT | Mesoscale Discussion | SPC | Calhoun, Chambers, Cherokee, Clay, Cleburne, Etowah and 8 more | 2 hr |
| Jul 21, 10:12 AM CDT | Severe Thunderstorm Watch | SPC | Henry, Houston | 5 hr |
| Jul 21, 4:42 PM CDT | Severe Thunderstorm Watch | SPC | Barbour, Bullock, Calhoun, Chambers, Cherokee, Clay and 9 more | 8 hr |
| Jul 21, 6:24 PM CDT | Mesoscale Discussion | SPC | Bullock, Calhoun, Chambers, Cherokee, Clay, Cleburne and 6 more | 96 min |
| Jul 21, 6:50 PM CDT | Severe Thunderstorm Watch | SPC | Henry, Houston | 5 hr |
| Jul 20, 7:02 PM CDT | Tornado Watch | SPC | Catoosa, Dade, Murray, Walker, Whitfield | 7 hr |
| Jul 21, 9:30 AM CDT | Mesoscale Discussion | SPC | Atkinson, Baker, Berrien, Brooks, Clinch, Coffee and 14 more | 90 min |
| Jul 20, 9:52 PM CDT | Mesoscale Discussion | SPC | Cherokee, Graham, Madison, Swain | 53 min |
Nearby
Mesoscale Discussions in Georgia, 2018Mesoscale Discussions in Tennessee, 2018Mesoscale Discussions in North Carolina, 2018Every mesoscale discussion in 2018
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.