Alert archive / Georgia / Mesoscale Discussions in 2021
Mesoscale Discussion 2086
The Storm Prediction Center issued this mesoscale discussion at Dec 30, 2021, 2:00 PM EST for 35 counties in Georgia. It was in force for 2 hr.
The area
The outline as issued.
The facts
- Issued
- Dec 30, 2021, 2:00 PM EST (19:00 UTC)
- Expired
- Dec 30, 2021, 4:00 PM EST
- In force
- 2 hr
- Issued by
- the Storm Prediction Center
- Concerning
- Severe potential...watch unlikely
- Chance of a watch
- 20%
All 35 counties
Appling County, GA, Atkinson County, GA, Bacon County, GA, Baker County, GA, Ben Hill County, GA, Berrien County, GA, Bryan County, GA, Coffee County, GA, Colquitt County, GA, Cook County, GA, Crisp County, GA, Decatur County, GA, Dodge County, GA, Dougherty County, GA, Evans County, GA, Grady County, GA, Irwin County, GA, Jeff Davis County, GA, Lee County, GA, Liberty County, GA, Long County, GA, Miller County, GA, Mitchell County, GA, Montgomery County, GA, Seminole County, GA, Tattnall County, GA, Telfair County, GA, Thomas County, GA, Tift County, GA, Toombs County, GA, Turner County, GA, Wayne County, GA, Wheeler County, GA, Wilcox County, GA, Worth County, GA
The radar
The Moody AFB radar (KVAX), 74 km from the middle of the area, began a volume at 19:01 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
Tallahassee Rgnl, FL (KTLH), launched 12:00Z, 7.0 hours before the alert went out and 173 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
- 850 J/kg
- Mixed-layer CIN
- -4 J/kg
- Mixed-layer LCL
- 526 m above ground
- 0-6 km bulk shear
- 38 kt
- 0-1 km storm-relative helicity
- 175 m²/s²
- 0-3 km storm-relative helicity
- 186 m²/s²
- Significant tornado parameter
- 0.6
- Supercell composite
- 3.9
The text
As transmitted.
156
ACUS11 KWNS 301901
SWOMCD
SPC MCD 301900
GAZ000-302100-
Mesoscale Discussion 2086
NWS Storm Prediction Center Norman OK
0100 PM CST Thu Dec 30 2021
Areas affected...portions of central into southern Georgia
Concerning...Severe potential...Watch unlikely
Valid 301900Z - 302100Z
Probability of Watch Issuance...20 percent
SUMMARY...Isolated severe thunderstorms may develop and continue for
at least a few more hours. Damaging gusts are the main threat,
though a tornado cannot be ruled out. A WW issuance farther south of
the main thunderstorm band in central Alabama/Georgia is unlikely
given the sparse nature of the severe threat, though convective
trends will continue to be monitored.
DISCUSSION...Thunderstorms have been slowly increasing in number and
intensity within a modest confluence band across southern into
central Georgia. KJGX radar shows that some of these storms recently
acquired supercell structure. These storms are developing in a
weakly forced environment, and are mainly fueled by deep low-level
moisture contributing to 1500-2000 J/kg MLCAPE (per 18Z
mesoanalysis). The presence of 40+ kts effective bulk shear will
promote continued organization with the more persistent updrafts.
However, some of the latest JGX VWPs depict short, modestly curved
hodographs. When taking into account the overall weak deep-layer
ascent, the weaker and veered low-level flow will limit the severe
threat to a degree, though damaging gusts and perhaps a tornado
could still occur. Nonetheless, the isolated nature of the severe
threat suggests that a WW issuance is unlikely.
..Squitieri/Hart.. 12/30/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...CHS...JAX...FFC...TAE...
LAT...LON 30948493 31668454 32268340 32308238 32248146 32078118
31918119 31548181 31188279 30878376 30748470 30948493SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Dec 29, 8:27 PM EST | Mesoscale Discussion | SPC | Bartow, Catoosa, Chattooga, Dade, Floyd, Gilmer and 5 more | 2 hr |
| Dec 29, 9:44 PM EST | Mesoscale Discussion | SPC | Banks, Barrow, Bartow, Chattooga, Cherokee, Clarke and 28 more | 2 hr |
| Dec 29, 10:16 PM EST | Tornado Watch | SPC | Banks, Barrow, Bartow, Butts, Carroll, Cherokee and 51 more | 7 hr |
| Dec 29, 11:56 PM EST | Mesoscale Discussion | SPC | Banks, Barrow, Butts, Carroll, Clarke, Clayton and 34 more | 2 hr |
| Dec 30, 2:15 AM EST | Mesoscale Discussion | SPC | Butts, Clayton, Coweta, Fayette, Greene, Heard and 15 more | 90 min |
| Dec 30, 5:02 AM EST | Mesoscale Discussion | SPC | Baldwin, Bibb, Butts, Columbia, Coweta, Glascock and 17 more | 2 hr |
| Dec 30, 11:34 AM EST | Mesoscale Discussion | SPC | Baldwin, Bibb, Bleckley, Butts, Chattahoochee, Crawford and 33 more | 116 min |
| Dec 30, 2:05 PM EST | Severe Thunderstorm Watch | SPC | Baldwin, Bibb, Bleckley, Bulloch, Burke, Candler and 45 more | 7 hr |
| Dec 30, 3:54 PM EST | Mesoscale Discussion | SPC | Baldwin, Bibb, Bleckley, Candler, Chattahoochee, Crawford and 36 more | 2 hr |
| Dec 30, 6:35 PM EST | Mesoscale Discussion | SPC | Appling, Atkinson, Bacon, Ben Hill, Berrien, Brantley and 32 more | 115 min |
Nearby
Mesoscale Discussions in Georgia, 2021Every mesoscale discussion 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.