Alert archive / Georgia / Mesoscale Discussions in 2021

Mesoscale Discussion 1414

August 1, 202134 counties in Alabama; 41 counties in Georgia; 23 counties in Mississippi

The Storm Prediction Center issued this mesoscale discussion at Aug 1, 2021, 12:09 PM CDT for 34 counties in Alabama; 41 counties in Georgia; 23 counties in Mississippi. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
Aug 1, 2021, 12:09 PM CDT (17:09 UTC)
Expired
Aug 1, 2021, 2:15 PM CDT
In force
2 hr
Issued by
the Storm Prediction Center
Concerning
Severe potential...watch unlikely
Chance of a watch
5%
All 98 counties

Autauga County, AL, Barbour County, AL, Bibb County, AL, Bullock County, AL, Butler County, AL, Chambers County, AL, Chilton County, AL, Choctaw County, AL, Clarke County, AL, Clay County, AL, Conecuh County, AL, Coosa County, AL, Crenshaw County, AL, Dallas County, AL, Elmore County, AL, Greene County, AL, Hale County, AL, Lee County, AL, Lowndes County, AL, Macon County, AL, Marengo County, AL, Monroe County, AL, Montgomery County, AL, Perry County, AL, Pickens County, AL, Pike County, AL, Randolph County, AL, Russell County, AL, Shelby County, AL, Sumter County, AL, Talladega County, AL, Tallapoosa County, AL, Tuscaloosa County, AL, Wilcox County, AL, Baldwin County, GA, Bibb County, GA, Bleckley County, GA, Butts County, GA, Chattahoochee County, GA, Coweta County, GA, Crawford County, GA, Crisp County, GA, Dooly County, GA, Fayette County, GA, Harris County, GA, Heard County, GA, Henry County, GA, Houston County, GA, Jasper County, GA, Jones County, GA, Lamar County, GA, Lee County, GA, Macon County, GA, Marion County, GA, Meriwether County, GA, Monroe County, GA, Muscogee County, GA, Peach County, GA, Pike County, GA, Pulaski County, GA, Quitman County, GA, Randolph County, GA, Schley County, GA, Spalding County, GA, Stewart County, GA, Sumter County, GA, Talbot County, GA, Taylor County, GA, Terrell County, GA, Troup County, GA, Twiggs County, GA, Upson County, GA, Webster County, GA, Wilcox County, GA, Wilkinson County, GA, Attala County, MS, Choctaw County, MS, Clarke County, MS, Covington County, MS, Holmes County, MS, Jasper County, MS, Jefferson Davis County, MS, Jones County, MS, Kemper County, MS, Lauderdale County, MS, Leake County, MS, Lowndes County, MS, Madison County, MS, Neshoba County, MS, Newton County, MS, Noxubee County, MS, Oktibbeha County, MS, Rankin County, MS, Scott County, MS, Simpson County, MS, Smith County, MS, Wayne County, MS, Winston County, MS

The radar

The Birmingham radar (KBMX), 52 km from the middle of the area, began a volume at 17:11 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, 5.2 hours before the alert went out and 52 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, Birmingham, AL at 12:00Z on 2021-08-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1867 joules per kilogram.LCLLFCEL10008507005003002001001 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, Birmingham, AL at 12:00Z on 2021-08-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 69 square meters per square second.1939Sfc1 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
1867 J/kg
Mixed-layer CIN
-38 J/kg
Mixed-layer LCL
834 m above ground
0-6 km bulk shear
22 kt
0-1 km storm-relative helicity
69 m²/s²
0-3 km storm-relative helicity
64 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

965 
ACUS11 KWNS 011710
SWOMCD
SPC MCD 011709 
GAZ000-ALZ000-MSZ000-011915-

Mesoscale Discussion 1414
NWS Storm Prediction Center Norman OK
1209 PM CDT Sun Aug 01 2021

Areas affected...Central MS...Central AL...Central GA

Concerning...Severe potential...Watch unlikely 

Valid 011709Z - 011915Z

Probability of Watch Issuance...5 percent

SUMMARY...Increasing thunderstorm coverage is expected this
afternoon. A few storms may become strong enough to produce damaging
wind gusts.

DISCUSSION...Recent surface analysis reveals an outflow boundary
extending southern AR eastward across central MS, AL, and GA. This
outflow boundary precedes the more baroclinic cold front to its
north. Visible satellite imagery shows increasingly deep cumulus
across much of the region ahead of the outflow boundary, with the
deepest cumulus currently in the vicinity of the small thunderstorm
cluster moving across east-central MS. Air mass downstream south of
the outflow boundary is characterized by temperatures in the upper
80s/low 90s, dewpoints in the mid 70s, and MLCAPE generally around
2000-2500 J/kg. 

Expectation is for scattered thunderstorm development across the
region this afternoon. This area will be displaced south of the
stronger flow aloft, but ample moisture coupled with strong buoyancy
will promote strong updrafts capable of producing wet microbursts.
Overall threat is expected to remain low enough to preclude watch
issuance.

..Mosier/Grams.. 08/01/2021

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...FFC...TAE...BMX...MOB...JAN...

LAT...LON   32259041 33339013 33628904 33458749 33378551 33488439
            33528376 33028307 31918320 31358698 31518988 32259041

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 31, 11:29 PM CDTSevere Thunderstorm WatchSPCDeKalb, Jackson, Lauderdale, Limestone, Madison3 hr

Nearby

Mesoscale Discussions in Georgia, 2021Mesoscale Discussions in Alabama, 2021Mesoscale Discussions in Mississippi, 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.