Alert archive / Alabama / Mesoscale Discussions in 2021
Mesoscale Discussion 1652
The Storm Prediction Center issued this mesoscale discussion at Aug 30, 2021, 3:13 PM CDT for 23 counties in Alabama; Escambia County, Santa Rosa County, Florida; 13 counties in Mississippi. It was in force for 2 hr.
The area
The outline as issued.
The facts
- Issued
- Aug 30, 2021, 3:13 PM CDT (20:13 UTC)
- Expired
- Aug 30, 2021, 5:15 PM CDT
- In force
- 2 hr
- Issued by
- the Storm Prediction Center
- Concerning
- Tornado watch 475
All 38 counties
Autauga County, AL, Baldwin County, AL, Bibb County, AL, Butler County, AL, Chilton County, AL, Choctaw County, AL, Clarke County, AL, Conecuh County, AL, Covington County, AL, Dallas County, AL, Escambia County, AL, Greene County, AL, Hale County, AL, Lowndes County, AL, Marengo County, AL, Mobile County, AL, Monroe County, AL, Perry County, AL, Pickens County, AL, Sumter County, AL, Tuscaloosa County, AL, Washington County, AL, Wilcox County, AL, Escambia County, FL, Santa Rosa County, FL, Clarke County, MS, George County, MS, Greene County, MS, Harrison County, MS, Jackson County, MS, Kemper County, MS, Lauderdale County, MS, Lowndes County, MS, Noxubee County, MS, Oktibbeha County, MS, Perry County, MS, Stone County, MS, Wayne County, MS
The radar
The Mobile radar (KMOB), 128 km from the middle of the area, began a volume at 20:17 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, 8.2 hours before the alert went out and 190 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
- 6 J/kg
- Mixed-layer CIN
- -242 J/kg
- Mixed-layer LCL
- 1267 m above ground
- 0-6 km bulk shear
- 29 kt
- 0-1 km storm-relative helicity
- 175 m²/s²
- 0-3 km storm-relative helicity
- 190 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.6
The text
As transmitted.
694
ACUS11 KWNS 302014
SWOMCD
SPC MCD 302013
ALZ000-FLZ000-MSZ000-302215-
Mesoscale Discussion 1652
NWS Storm Prediction Center Norman OK
0313 PM CDT Mon Aug 30 2021
Areas affected...eastern Mississippi into Alabama...western Florida
Panhandle
Concerning...Tornado Watch 475...
Valid 302013Z - 302215Z
The severe weather threat for Tornado Watch 475 continues.
SUMMARY...Conditions remain sufficiently favorable for a tornado
risk in association with Ida. The primary risk area appears to be
from eastern Mississippi into western Alabama.
DISCUSSION...Three primary bands of convection persist from MS into
AL and the FL Panhandle this afternoon. The middle band has been the
most productive in terms of tornado risk, but has lost intensity
with time as it translated east into central AL. Widespread rain is
likely limited potential here.
To the east, scattered storms persist across southeast AL and into
the FL Panhandle. Here, instability is maximized, but this area is
on the eastern fringe of the more favorable shear. As such, the
tornado risk here may remain low.
In the near term, the most favorable area may be with a newly
developed band consisting of broken cells over far eastern MS. The
environment here consists of 250+ 0-1 km SRH, as well as a narrow
sector of recovering air mass out of the southwest. This may yield a
tornado risk which may shift again into parts of AL.
..Jewell.. 08/30/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...BMX...MOB...JAN...LIX...
LAT...LON 30178898 30348927 30948918 31448885 32388870 33028894
33328907 33508895 33528842 33548766 33478718 33318677
32848642 32128637 31088646 30548665 30258689 30168787
30148837 30178898SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 30, 2:44 AM CDT | Mesoscale Discussion | SPC | Baldwin, Clarke, Conecuh, Escambia, Mobile, Monroe and 1 more | 2 hr |
| Aug 30, 5:48 AM CDT | Tornado Watch | SPC | Baldwin, Butler, Choctaw, Clarke, Conecuh, Covington and 6 more | 10 hr |
| Aug 30, 12:02 PM CDT | Mesoscale Discussion | SPC | Bibb, Chilton, Colbert, Fayette, Franklin, Jefferson and 8 more | 2 hr |
| Aug 30, 12:03 PM CDT | Mesoscale Discussion | SPC | Bibb, Chilton, Colbert, Fayette, Franklin, Jefferson and 8 more | 4 hr |
Nearby
Mesoscale Discussions in Alabama, 2021Mesoscale Discussions in Mississippi, 2021Mesoscale Discussions in Florida, 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.