Alert archive / Alabama / Tornado Watches in 2021
Tornado Watch 144
The Storm Prediction Center issued this tornado watch at May 4, 2021, 9:18 AM CDT for 34 counties in Alabama; 32 counties in Mississippi. It was in force for 7 hr.
The area
The outline as issued.
The facts
- Issued
- May 4, 2021, 9:18 AM CDT (14:18 UTC)
- Expired
- May 4, 2021, 4:00 PM CDT
- In force
- 7 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 2 in
- Strongest gust expected
- 65 kt
All 66 counties
Autauga County, AL, Bibb County, AL, Blount County, AL, Calhoun County, AL, Cherokee County, AL, Chilton County, AL, Choctaw County, AL, Clarke County, AL, Clay County, AL, Cleburne County, AL, Coosa County, AL, Cullman County, AL, Dallas County, AL, DeKalb County, AL, Etowah County, AL, Fayette County, AL, Greene County, AL, Hale County, AL, Jefferson County, AL, Lamar County, AL, Marengo County, AL, Marshall County, AL, Morgan County, AL, Perry County, AL, Pickens County, AL, Shelby County, AL, St. Clair County, AL, Sumter County, AL, Talladega County, AL, Tuscaloosa County, AL, Walker County, AL, Washington County, AL, Wilcox County, AL, Winston County, AL, Attala County, MS, Carroll County, MS, Choctaw County, MS, Clarke County, MS, Clay County, MS, Copiah County, MS, Covington County, MS, Hinds County, MS, Holmes County, MS, Jasper County, MS, Jefferson Davis County, MS, Jones County, MS, Kemper County, MS, Lauderdale County, MS, Lawrence County, MS, Leake County, MS, Lincoln County, MS, Lowndes County, MS, Madison County, MS, Montgomery 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, Webster County, MS, Winston County, MS, Yazoo County, MS
The radar
The Birmingham radar (KBMX), 41 km from the middle of the area, began a volume at 14:19 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
- 50%
- One or more EF2 to EF5 tornadoes
- 20%
- Ten or more severe wind reports
- 80%
- One or more gusts of 65 knots or more
- 40%
- Ten or more severe hail reports
- 30%
- One or more hailstones of 2 inches or more
- 30%
- Six or more combined severe hail and wind reports
- 95%
Warnings issued inside it
59 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 4, 9:31 AM CDT | Severe Thunderstorm Warning | HUN | Cullman, Morgan | 39 min |
| May 4, 9:39 AM CDT | Severe Thunderstorm Warning | HUN | DeKalb, Jackson | 36 min |
| May 4, 9:51 AM CDT | Severe Thunderstorm Warning | HUN | DeKalb | 24 min |
| May 4, 10:02 AM CDT | Severe Thunderstorm Warning | JAN | Choctaw, Oktibbeha | 43 min |
| May 4, 10:15 AM CDT | Flash Flood Warning | JAN | Clay, Webster | 2 hr |
| May 4, 10:26 AM CDT | Severe Thunderstorm Warning | BMX | Blount | 23 min |
| May 4, 10:47 AM CDT | Flash Flood Warning | HUN | DeKalb, Marshall | 3 hr |
| May 4, 11:12 AM CDT | Tornado Warning | BMX | Fayette, Tuscaloosa | 21 min |
| May 4, 11:18 AM CDT | Severe Thunderstorm Warning | HUN | Cullman | 42 min |
| May 4, 11:25 AM CDT | Severe Thunderstorm Warning | BMX | Jefferson, Walker | 50 min |
| May 4, 11:49 AM CDT | Severe Thunderstorm Warning | BMX | Blount, Jefferson, St. Clair | 26 min |
| May 4, 12:03 PM CDT | Flash Flood Warning | BMX | Blount, Etowah, St. Clair | 117 min |
| May 4, 12:07 PM CDT | Severe Thunderstorm Warning | JAN | Madison, Rankin | 38 min |
| May 4, 12:10 PM CDT | Flash Flood Warning | BMX | Jefferson | 7 hr |
| May 4, 12:14 PM CDT | Severe Thunderstorm Warning | BMX | Calhoun, St. Clair, Talladega | 46 min |
| May 4, 12:17 PM CDT | Severe Thunderstorm Warning | BMX | Jefferson, St. Clair, Shelby | 28 min |
| May 4, 12:35 PM CDT | Flash Flood Warning | BMX | Calhoun, Etowah, St. Clair, Talladega | 3 hr |
| May 4, 12:40 PM CDT | Severe Thunderstorm Warning | JAN | Leake, Madison | 50 min |
| May 4, 12:46 PM CDT | Severe Thunderstorm Warning | JAN | Madison, Yazoo | 44 min |
| May 4, 12:47 PM CDT | Severe Thunderstorm Warning | JAN | Copiah | 43 min |
| May 4, 12:56 PM CDT | Severe Thunderstorm Warning | BMX | Calhoun, Cherokee, Cleburne, Talladega | 64 min |
| May 4, 1:10 PM CDT | Severe Thunderstorm Warning | JAN | Leake | 50 min |
| May 4, 1:15 PM CDT | Severe Thunderstorm Warning | BMX | Jefferson, Shelby | 30 min |
| May 4, 1:19 PM CDT | Severe Thunderstorm Warning | JAN | Rankin, Scott, Smith | 41 min |
| May 4, 1:22 PM CDT | Severe Thunderstorm Warning | JAN | Holmes, Humphreys, Issaquena, Sharkey, Washington, Yazoo | 71 min |
| May 4, 1:25 PM CDT | Tornado Warning | BMX | Cleburne | 24 min |
| May 4, 1:31 PM CDT | Severe Thunderstorm Warning | JAN | Rankin, Simpson | 44 min |
| May 4, 1:37 PM CDT | Severe Thunderstorm Warning | JAN | Hinds, Issaquena, Warren, Yazoo | 53 min |
| May 4, 1:39 PM CDT | Flash Flood Warning | BMX | Jefferson, St. Clair, Shelby | 5 hr |
| May 4, 1:44 PM CDT | Severe Thunderstorm Warning | JAN | Carroll, Grenada, Montgomery | 75 min |
| May 4, 1:52 PM CDT | Tornado Warning | JAN | Rankin, Scott, Smith | 23 min |
| May 4, 1:57 PM CDT | Severe Thunderstorm Warning | JAN | Adams, Claiborne, Copiah, Franklin, Hinds, Jefferson and 1 more | 78 min |
| May 4, 2:00 PM CDT | Severe Thunderstorm Warning | JAN | Leake, Neshoba | 45 min |
| May 4, 2:09 PM CDT | Severe Thunderstorm Warning | JAN | Attala, Holmes, Leake, Madison, Rankin, Scott and 1 more | 66 min |
| May 4, 2:12 PM CDT | Severe Thunderstorm Warning | JAN | Copiah, Hinds, Madison, Rankin, Scott, Simpson and 1 more | 93 min |
| May 4, 2:12 PM CDT | Severe Thunderstorm Warning | JAN | Attala, Carroll, Choctaw, Holmes, Montgomery | 63 min |
| May 4, 2:22 PM CDT | Tornado Warning | JAN | Attala, Holmes, Madison, Yazoo | 20 min |
| May 4, 2:29 PM CDT | Severe Thunderstorm Warning | JAN | Webster | 61 min |
| May 4, 2:30 PM CDT | Severe Thunderstorm Warning | JAN | Webster | 60 min |
| May 4, 2:33 PM CDT | Severe Thunderstorm Warning | JAN | Winston | 42 min |
| May 4, 2:35 PM CDT | Tornado Warning | JAN | Hinds, Madison, Rankin | 25 min |
| May 4, 2:40 PM CDT | Severe Thunderstorm Warning | JAN | Copiah, Franklin, Jefferson Davis, Lawrence, Lincoln, Simpson | 80 min |
| May 4, 2:44 PM CDT | Severe Thunderstorm Warning | JAN | Newton, Scott, Smith | 46 min |
| May 4, 2:53 PM CDT | Tornado Warning | JAN | Rankin, Scott, Smith | 18 min |
| May 4, 3:02 PM CDT | Severe Thunderstorm Warning | JAN | Noxubee | 28 min |
| May 4, 3:03 PM CDT | Severe Thunderstorm Warning | JAN | Choctaw, Oktibbeha, Winston | 57 min |
| May 4, 3:08 PM CDT | Severe Thunderstorm Warning | JAN | Leake, Neshoba | 52 min |
| May 4, 3:09 PM CDT | Severe Thunderstorm Warning | JAN | Jasper, Smith | 51 min |
| May 4, 3:09 PM CDT | Severe Thunderstorm Warning | JAN | Jasper, Newton, Scott, Simpson, Smith | 81 min |
| May 4, 3:18 PM CDT | Severe Thunderstorm Warning | JAN | Kemper, Noxubee | 42 min |
| May 4, 3:20 PM CDT | Tornado Warning | JAN | Leake, Neshoba, Newton, Scott | 40 min |
| May 4, 3:32 PM CDT | Tornado Warning | JAN | Clarke, Jasper | 29 min |
| May 4, 3:36 PM CDT | Severe Thunderstorm Warning | JAN | Lauderdale | 54 min |
| May 4, 3:38 PM CDT | Severe Thunderstorm Warning | JAN | Covington, Jefferson Davis, Jones, Lamar, Lawrence, Lincoln and 1 more | 82 min |
| May 4, 3:49 PM CDT | Severe Thunderstorm Warning | JAN | Lowndes, Noxubee | 29 min |
| May 4, 3:50 PM CDT | Severe Thunderstorm Warning | BMX | Sumter | 55 min |
| May 4, 3:50 PM CDT | Severe Thunderstorm Warning | JAN | Clarke | 55 min |
| May 4, 3:55 PM CDT | Severe Thunderstorm Warning | MOB | Choctaw, Clarke, Washington | 65 min |
| May 4, 3:58 PM CDT | Severe Thunderstorm Warning | JAN | Kemper | 32 min |
Discussions around it
SPC mesoscale discussions over the same counties from four hours before the watch to its end.
The nearest sounding before it
Birmingham, AL (KBMX), launched 12:00Z, 2.3 hours before the alert went out and 40 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
- 2158 J/kg
- Mixed-layer CIN
- -5 J/kg
- Mixed-layer LCL
- 569 m above ground
- 0-6 km bulk shear
- 28 kt
- 0-1 km storm-relative helicity
- 145 m²/s²
- 0-3 km storm-relative helicity
- 195 m²/s²
- Significant tornado parameter
- 1.4
- Supercell composite
- 7.3
The text
As transmitted.
542
WWUS20 KWNS 041416
SEL4
SPC WW 041416
ALZ000-MSZ000-042100-
URGENT - IMMEDIATE BROADCAST REQUESTED
Tornado Watch Number 144
NWS Storm Prediction Center Norman OK
920 AM CDT Tue May 4 2021
The NWS Storm Prediction Center has issued a
* Tornado Watch for portions of
Alabama
Central Mississippi
* Effective this Tuesday morning and afternoon from 920 AM until
400 PM CDT.
* Primary threats include...
A few tornadoes possible
Widespread damaging winds likely with isolated significant gusts
to 75 mph possible
Isolated very large hail events to 2 inches in diameter possible
SUMMARY...A discrete supercell over central Mississippi may persist
this morning with additional discrete supercells possible into
west-central and southwest Alabama. Otherwise, an intensifying
squall line is expected to evolve east across northern and central
Alabama with damaging winds and a few tornadoes as the primary
hazards.
The tornado watch area is approximately along and 80 statute miles
east and west of a line from 40 miles north northwest of Gadsden AL
to 55 miles south southwest of Meridian MS. For a complete depiction
of the watch see the associated watch outline update (WOUS64 KWNS
WOU4).
PRECAUTIONARY/PREPAREDNESS ACTIONS...
REMEMBER...A Tornado Watch means conditions are favorable for
tornadoes and 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.
&&
OTHER WATCH INFORMATION...CONTINUE...WW 141...WW 142...WW 143...
AVIATION...Tornadoes and a few severe thunderstorms with hail
surface and aloft to 2 inches. Extreme turbulence and surface wind
gusts to 65 knots. A few cumulonimbi with maximum tops to 500. Mean
storm motion vector 25035.
...GramsSPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 3, 7:13 PM CDT | Mesoscale Discussion | SPC | Autauga, Bullock, Chambers, Coosa, Elmore, Lee and 4 more | 62 min |
| May 4, 5:13 AM CDT | Severe Thunderstorm Watch | SPC | Jackson, Lauderdale, Limestone, Madison | 5 hr |
| May 4, 7:31 AM CDT | Mesoscale Discussion | SPC | Jackson, Lauderdale, Limestone, Madison | 89 min |
| May 4, 8:33 AM CDT | Mesoscale Discussion | SPC | Choctaw, Clarke, Dallas, Greene, Hale, Marengo and 4 more | 117 min |
| May 4, 9:03 AM CDT | Mesoscale Discussion | SPC | Blount, Calhoun, Cherokee, Clay, Cleburne, Cullman and 20 more | 117 min |
| May 4, 2:17 PM CDT | Mesoscale Discussion | SPC | Choctaw, Greene, Marengo, Sumter | 88 min |
| May 4, 3:03 PM CDT | Mesoscale Discussion | SPC | Bibb, Blount, Calhoun, Cherokee, Chilton, Clay and 19 more | 117 min |
| May 4, 3:31 PM CDT | Tornado Watch | SPC | Autauga, Baldwin, Bibb, Butler, Chilton, Choctaw and 20 more | 6 hr |
| May 4, 4:46 PM CDT | Mesoscale Discussion | SPC | Autauga, Baldwin, Bibb, Butler, Chilton, Choctaw and 20 more | 89 min |
| May 4, 5:20 PM CDT | Mesoscale Discussion | SPC | Barbour, Bullock, Chambers, Coffee, Covington, Dale and 7 more | 85 min |
| May 4, 6:10 PM CDT | Mesoscale Discussion | SPC | Autauga, Coosa, Elmore, Lowndes, Macon, Montgomery and 1 more | 65 min |
| May 4, 6:26 PM CDT | Severe Thunderstorm Watch | SPC | Barbour, Bullock, Chambers, Coffee, Covington, Crenshaw and 8 more | 6 hr |
| May 4, 9:48 AM CDT | Severe Thunderstorm Watch | SPC | Banks, Barrow, Bartow, Butts, Carroll, Catoosa and 43 more | 6 hr |
| May 4, 12:21 PM CDT | Mesoscale Discussion | SPC | Banks, Barrow, Bartow, Carroll, Cherokee, Clarke and 34 more | 114 min |
| May 4, 2:07 PM CDT | Mesoscale Discussion | SPC | Banks, Barrow, Bartow, Butts, Carroll, Cherokee and 35 more | 113 min |
| May 4, 3:56 PM CDT | Severe Thunderstorm Watch | SPC | Burke, Columbia, McDuffie, Richmond | 3 hr |
| May 4, 10:52 AM CDT | Tornado Watch | SPC | Adams, Amite, Bolivar, Claiborne, Franklin, Grenada and 9 more | 7 hr |
| May 4, 11:58 AM CDT | Mesoscale Discussion | SPC | Alcorn, Benton, Calhoun, Chickasaw, Coahoma, DeSoto and 13 more | 2 hr |
| May 4, 12:16 PM CDT | Mesoscale Discussion | SPC | Adams, Claiborne, Copiah, Franklin, Hinds, Issaquena and 4 more | 89 min |
| May 4, 12:18 PM CDT | Severe Thunderstorm Watch | SPC | Alcorn, Benton, Calhoun, Chickasaw, Coahoma, DeSoto and 16 more | 5 hr |
Nearby
Tornado Watches in Alabama, 2021Tornado Watches in Mississippi, 2021Every tornado 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.