Alert archive / Georgia / Severe Thunderstorm Watches in 2021
Severe Thunderstorm Watch 145
The Storm Prediction Center issued this severe thunderstorm watch at May 4, 2021, 10:48 AM EDT for 49 counties in Georgia. It was in force for 6 hr.
The area
The outline as issued.
The facts
- Issued
- May 4, 2021, 10:48 AM EDT (14:48 UTC)
- Expired
- May 4, 2021, 5:00 PM EDT
- In force
- 6 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 1 in
- Strongest gust expected
- 60 kt
All 49 counties
Banks County, GA, Barrow County, GA, Bartow County, GA, Butts County, GA, Carroll County, GA, Catoosa County, GA, Chattooga County, GA, Cherokee County, GA, Clarke 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, Fulton County, GA, Gilmer County, GA, Gordon County, GA, Greene County, GA, Gwinnett County, GA, Hall County, GA, Haralson County, GA, Heard County, GA, Henry County, GA, Jackson County, GA, Jasper County, GA, Lumpkin County, GA, Madison County, GA, Morgan County, GA, Murray County, GA, Newton County, GA, Oconee County, GA, Oglethorpe County, GA, Paulding County, GA, Pickens County, GA, Polk County, GA, Rockdale County, GA, Spalding County, GA, Towns County, GA, Union County, GA, Walker County, GA, Walton County, GA, White County, GA, Whitfield County, GA
The radar
The Atlanta radar (KFFC), 95 km from the middle of the area, began a volume at 14:48 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.
What SPC expected
The probabilities SPC published with the watch, for the watch area over its life.
- Two or more tornadoes
- 20%
- One or more EF2 to EF5 tornadoes
- 10%
- Ten or more severe wind reports
- 40%
- One or more gusts of 65 knots or more
- 20%
- Ten or more severe hail reports
- 10%
- One or more hailstones of 2 inches or more
- 10%
- Six or more combined severe hail and wind reports
- 60%
Warnings issued inside it
9 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 4, 11:05 AM EDT | Severe Thunderstorm Warning | FFC | Chattooga, Dade, Floyd, Walker, Whitfield | 25 min |
| May 4, 11:25 AM EDT | Severe Thunderstorm Warning | FFC | Catoosa, Murray, Walker, Whitfield | 35 min |
| May 4, 12:35 PM EDT | Severe Thunderstorm Warning | FFC | Bartow, Cherokee, Dawson, Gilmer, Gordon, Pickens | 40 min |
| May 4, 12:59 PM EDT | Severe Thunderstorm Warning | FFC | Bartow, Cherokee, Cobb, Paulding, Polk | 31 min |
| May 4, 1:28 PM EDT | Severe Thunderstorm Warning | FFC | Carroll, Cobb, Douglas, Haralson, Paulding | 32 min |
| May 4, 1:52 PM EDT | Severe Thunderstorm Warning | FFC | Cobb, Forsyth, Fulton, Gwinnett, Hall | 38 min |
| May 4, 2:16 PM EDT | Severe Thunderstorm Warning | FFC | Bartow, Carroll, Floyd, Haralson, Paulding, Polk | 44 min |
| May 4, 2:57 PM EDT | Severe Thunderstorm Warning | FFC | Bartow, Carroll, Cherokee, Cobb, Douglas, Fulton and 3 more | 48 min |
| May 4, 3:08 PM EDT | Flash Flood Warning | FFC | Barrow, Carroll, Cobb, DeKalb, Douglas, Fulton and 6 more | 7 hr |
Discussions around it
SPC mesoscale discussions over the same counties from four hours before the watch to its end.
The nearest sounding before it
Peachtre/Fal Fld, GA (KFFC), launched 12:00Z, 2.8 hours before the alert went out and 94 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
- 590 J/kg
- Mixed-layer CIN
- -114 J/kg
- Mixed-layer LCL
- 753 m above ground
- 0-6 km bulk shear
- 39 kt
- 0-1 km storm-relative helicity
- 207 m²/s²
- 0-3 km storm-relative helicity
- 213 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 2.3
The text
As transmitted.
008 WWUS20 KWNS 041442 SEL5 SPC WW 041442 GAZ000-042100- URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 145 NWS Storm Prediction Center Norman OK 1045 AM EDT Tue May 4 2021 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of North Georgia * Effective this Tuesday morning and afternoon from 1045 AM until 500 PM EDT. * Primary threats include... Scattered damaging wind gusts to 70 mph possible A tornado or two possible SUMMARY...Multiple clusters and linear segments should spread east from north Alabama across north Georgia with a primary risk being damaging winds and perhaps a brief tornado. The severe thunderstorm watch area is approximately along and 55 statute miles north and south of a line from 20 miles south southwest of Rome GA to 70 miles east northeast of Atlanta GA. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU5). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Severe Thunderstorm Watch means conditions are favorable for severe thunderstorms in and close to the watch area. Persons in these areas should be on the lookout for threatening weather conditions and listen for later statements and possible warnings. Severe thunderstorms can and occasionally do produce tornadoes. && OTHER WATCH INFORMATION...CONTINUE...WW 141...WW 142...WW 143...WW 144... AVIATION...A few severe thunderstorms with hail surface and aloft to 1 inch. Extreme turbulence and surface wind gusts to 60 knots. A few cumulonimbi with maximum tops to 450. Mean storm motion vector 27035. ...Grams
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 4, 8:31 AM EDT | Mesoscale Discussion | SPC | Dade | 89 min |
| May 4, 10:03 AM EDT | Mesoscale Discussion | SPC | Bartow, Carroll, Chattooga, Cherokee, Cobb, Douglas and 8 more | 117 min |
| May 4, 1:21 PM EDT | Mesoscale Discussion | SPC | Banks, Barrow, Bartow, Carroll, Cherokee, Clarke and 34 more | 114 min |
| May 4, 3:07 PM EDT | Mesoscale Discussion | SPC | Banks, Barrow, Bartow, Butts, Carroll, Cherokee and 35 more | 113 min |
| May 4, 4:56 PM EDT | Severe Thunderstorm Watch | SPC | Burke, Columbia, McDuffie, Richmond | 3 hr |
| May 4, 6:20 PM EDT | Mesoscale Discussion | SPC | Baker, Bibb, Calhoun, Chattahoochee, Clay, Colquitt and 34 more | 85 min |
| May 4, 7:26 PM EDT | Severe Thunderstorm Watch | SPC | Baker, Ben Hill, Berrien, Bibb, Bleckley, Brooks and 45 more | 6 hr |
Nearby
Severe Thunderstorm Watches in Georgia, 2021Every severe thunderstorm watch in 2021
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.