Alert archive / Alabama / Severe Thunderstorm Watches in 2021

Severe Thunderstorm Watch 108

April 24, 202129 counties in Alabama; 7 counties in Florida; 5 counties in Mississippi

The Storm Prediction Center issued this severe thunderstorm watch at Apr 24, 2021, 1:17 PM CDT for 29 counties in Alabama; 7 counties in Florida; 5 counties in Mississippi. It was in force for 8 hr.

The area

The outline as issued.

The facts

Issued
Apr 24, 2021, 1:17 PM CDT (18:17 UTC)
Expired
Apr 24, 2021, 9:00 PM CDT
In force
8 hr
Issued by
the Storm Prediction Center
Largest hail expected
2 in
Strongest gust expected
60 kt
All 41 counties

Autauga County, AL, Baldwin County, AL, Barbour County, AL, Bullock County, AL, Butler County, AL, Choctaw County, AL, Clarke County, AL, Coffee County, AL, Conecuh County, AL, Covington County, AL, Crenshaw County, AL, Dale County, AL, Dallas County, AL, Elmore County, AL, Escambia County, AL, Geneva County, AL, Henry County, AL, Houston County, AL, Lee County, AL, Lowndes County, AL, Macon County, AL, Marengo County, AL, Mobile County, AL, Monroe County, AL, Montgomery County, AL, Pike County, AL, Russell County, AL, Washington County, AL, Wilcox County, AL, Escambia County, FL, Holmes County, FL, Jackson County, FL, Okaloosa County, FL, Santa Rosa County, FL, Walton County, FL, Washington County, FL, George County, MS, Greene County, MS, Perry County, MS, Stone County, MS, Wayne County, MS

The radar

The Mobile radar (KMOB), 115 km from the middle of the area, began a volume at 18:16 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
5%
Ten or more severe wind reports
60%
One or more gusts of 65 knots or more
20%
Ten or more severe hail reports
70%
One or more hailstones of 2 inches or more
30%
Six or more combined severe hail and wind reports
95%

Warnings issued inside it

55 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
Apr 24, 1:17 PM CDTTornado WarningMOBCovington18 min
Apr 24, 1:19 PM CDTSevere Thunderstorm WarningMOBConecuh, Escambia, Monroe45 min
Apr 24, 1:20 PM CDTTornado WarningTAECoffee, Dale, Geneva40 min
Apr 24, 1:55 PM CDTSevere Thunderstorm WarningMOBCovington26 min
Apr 24, 2:12 PM CDTSevere Thunderstorm WarningTAECoffee, Dale, Geneva, Henry, Houston63 min
Apr 24, 2:29 PM CDTSevere Thunderstorm WarningMOBConecuh, Monroe46 min
Apr 24, 2:39 PM CDTTornado WarningTAEDale, Henry, Houston19 min
Apr 24, 2:49 PM CDTSevere Thunderstorm WarningTAEHenry, Houston56 min
Apr 24, 2:52 PM CDTTornado WarningMOBConecuh38 min
Apr 24, 3:15 PM CDTSevere Thunderstorm WarningMOBClarke45 min
Apr 24, 3:20 PM CDTSevere Thunderstorm WarningMOBButler, Covington, Crenshaw40 min
Apr 24, 3:27 PM CDTTornado WarningMOBClarke25 min
Apr 24, 3:28 PM CDTSevere Thunderstorm WarningBMXMacon, Montgomery32 min
Apr 24, 3:41 PM CDTSevere Thunderstorm WarningMOBMonroe, Wilcox49 min
Apr 24, 3:43 PM CDTSevere Thunderstorm WarningMOBClarke, Washington47 min
Apr 24, 3:44 PM CDTSevere Thunderstorm WarningBMXMacon, Tallapoosa31 min
Apr 24, 3:46 PM CDTTornado WarningMOBMonroe, Wilcox44 min
Apr 24, 3:46 PM CDTSevere Thunderstorm WarningTAECoffee, Dale44 min
Apr 24, 3:58 PM CDTSevere Thunderstorm WarningBMXLee35 min
Apr 24, 3:59 PM CDTSevere Thunderstorm WarningMOBWashington46 min
Apr 24, 4:10 PM CDTSevere Thunderstorm WarningMOBClarke, Conecuh, Monroe50 min
Apr 24, 4:10 PM CDTTornado WarningMOBMonroe, Wilcox35 min
Apr 24, 4:24 PM CDTSevere Thunderstorm WarningTAECoffee, Dale, Henry51 min
Apr 24, 4:28 PM CDTTornado WarningMOBButler27 min
Apr 24, 4:32 PM CDTSevere Thunderstorm WarningMOBClarke, Washington43 min
Apr 24, 4:34 PM CDTSevere Thunderstorm WarningMOBWashington20 min
Apr 24, 4:35 PM CDTSevere Thunderstorm WarningBMXElmore, Montgomery36 min
Apr 24, 4:47 PM CDTSevere Thunderstorm WarningMOBButler, Covington, Crenshaw43 min
Apr 24, 4:51 PM CDTSevere Thunderstorm WarningMOBButler, Conecuh, Monroe39 min
Apr 24, 4:54 PM CDTSevere Thunderstorm WarningMOBButler, Crenshaw51 min
Apr 24, 4:55 PM CDTSevere Thunderstorm WarningBMXLee, Macon, Tallapoosa38 min
Apr 24, 4:59 PM CDTSevere Thunderstorm WarningMOBMonroe46 min
Apr 24, 5:04 PM CDTSevere Thunderstorm WarningTAECoffee41 min
Apr 24, 5:20 PM CDTSevere Thunderstorm WarningMOBMobile40 min
Apr 24, 5:21 PM CDTSevere Thunderstorm WarningMOBButler, Covington, Crenshaw39 min
Apr 24, 5:23 PM CDTSevere Thunderstorm WarningBMXPike52 min
Apr 24, 5:23 PM CDTSevere Thunderstorm WarningTAEDale, Henry37 min
Apr 24, 5:24 PM CDTSevere Thunderstorm WarningMOBConecuh, Monroe66 min
Apr 24, 5:43 PM CDTSevere Thunderstorm WarningBMXBarbour, Bullock47 min
Apr 24, 5:56 PM CDTSevere Thunderstorm WarningMOBCovington, Crenshaw64 min
Apr 24, 5:57 PM CDTSevere Thunderstorm WarningMOBBaldwin, Mobile48 min
Apr 24, 5:59 PM CDTSevere Thunderstorm WarningTAECoffee31 min
Apr 24, 6:05 PM CDTSevere Thunderstorm WarningTAEHenry40 min
Apr 24, 6:12 PM CDTSevere Thunderstorm WarningBMXBarbour18 min
Apr 24, 6:22 PM CDTSevere Thunderstorm WarningBMXBarbour, Pike38 min
Apr 24, 6:24 PM CDTSevere Thunderstorm WarningMOBBaldwin, Conecuh, Escambia, Monroe29 min
Apr 24, 6:24 PM CDTSevere Thunderstorm WarningTAECoffee, Dale66 min
Apr 24, 6:27 PM CDTSevere Thunderstorm WarningMOBBaldwin, Escambia48 min
Apr 24, 6:29 PM CDTSevere Thunderstorm WarningMOBConecuh31 min
Apr 24, 6:47 PM CDTSevere Thunderstorm WarningTAEHenry43 min
Apr 24, 7:00 PM CDTSevere Thunderstorm WarningMOBConecuh, Covington, Escambia45 min
Apr 24, 7:01 PM CDTSevere Thunderstorm WarningMOBBaldwin15 min
Apr 24, 7:06 PM CDTSevere Thunderstorm WarningTAEDale, Henry39 min
Apr 24, 7:23 PM CDTSevere Thunderstorm WarningTAECoffee, Dale, Geneva, Henry, Houston52 min
Apr 24, 7:37 PM CDTSevere Thunderstorm WarningTAEHenry39 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, 6.3 hours before the alert went out and 200 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 2021-04-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 2021-04-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 855 square meters per square second.19395878Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
580 m above ground
0-6 km bulk shear
62 kt
0-1 km storm-relative helicity
855 m²/s²
0-3 km storm-relative helicity
1103 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

967 
WWUS20 KWNS 241814
SEL8  
SPC WW 241814
ALZ000-FLZ000-MSZ000-CWZ000-250200-

URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 108
NWS Storm Prediction Center Norman OK
115 PM CDT Sat Apr 24 2021

The NWS Storm Prediction Center has issued a

* Severe Thunderstorm Watch for portions of 
  Southern Alabama
  Florida Panhandle
  Southeast Mississippi
  Coastal Waters

* Effective this Saturday afternoon and evening from 115 PM until
  900 PM CDT.

* Primary threats include...
  Scattered large hail likely with isolated very large hail events
    to 2 inches in diameter possible
  Scattered damaging wind gusts to 70 mph likely
  A tornado or two possible

SUMMARY...Scattered strong to severe thunderstorms are expected to
develop across the watch area through the afternoon.  The strongest
storms will pose a risk of large hail and gusty/damaging wind gusts.
 An isolated tornado or two is also possible.

The severe thunderstorm watch area is approximately along and 75
statute miles north and south of a line from 50 miles north of
Gulfport MS to 25 miles east northeast of Dothan AL. For a complete
depiction of the watch see the associated watch outline update
(WOUS64 KWNS WOU8).

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 106...WW 107...

AVIATION...A few severe thunderstorms with hail surface and aloft to
2 inches. Extreme turbulence and surface wind gusts to 60 knots. A
few cumulonimbi with maximum tops to 500. Mean storm motion vector
25030.

...Hart

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 24, 1:00 AM CDTMesoscale DiscussionSPCBaldwin, Coffee, Conecuh, Covington, Escambia, Geneva and 2 more3 hr
Apr 24, 1:00 AM CDTMesoscale DiscussionSPCBaldwin, Coffee, Conecuh, Covington, Escambia, Geneva and 2 more3 hr
Apr 24, 1:23 AM CDTTornado WatchSPCBaldwin, Clarke, Conecuh, Covington, Escambia, Mobile and 2 more8 hr
Apr 24, 3:04 AM CDTMesoscale DiscussionSPCBaldwin, Mobile, Washington116 min
Apr 24, 4:26 AM CDTMesoscale DiscussionSPCConecuh, Covington, Escambia, Monroe, Washington2 hr
Apr 24, 5:22 AM CDTTornado WatchSPCCoffee, Dale, Geneva, Henry, Houston9 hr
Apr 24, 7:29 AM CDTMesoscale DiscussionSPCCoffee, Dale, Geneva, Henry, Houston91 min
Apr 24, 12:29 PM CDTMesoscale DiscussionSPCBaldwin, Choctaw, Clarke, Conecuh, Escambia, Marengo and 4 more2 hr
Apr 24, 1:22 PM CDTMesoscale DiscussionSPCBlount, Calhoun, Cherokee, Clay, Cleburne, Colbert and 22 more113 min
Apr 24, 3:40 PM CDTMesoscale DiscussionSPCAutauga, Barbour, Bullock, Butler, Clarke, Coffee and 19 more95 min
Apr 24, 4:52 PM CDTSevere Thunderstorm WatchSPCBibb, Blount, Calhoun, Chambers, Cherokee, Chilton and 15 more4 hr
Apr 24, 5:56 PM CDTMesoscale DiscussionSPCBarbour, Bullock, Coffee, Dale, Henry, Houston and 1 more94 min
Apr 24, 6:13 PM CDTMesoscale DiscussionSPCCalhoun, Chambers, Cherokee, Clay, Cleburne, Coosa and 6 more2 hr
Apr 24, 9:10 AM CDTMesoscale DiscussionSPCNassau95 min
Apr 24, 9:35 AM CDTTornado WatchSPCBaker, Columbia, Duval, Hamilton, Nassau, Suwannee7 hr
Apr 24, 11:05 AM CDTMesoscale DiscussionSPCCalhoun, Gadsden, Holmes, Jackson, Jefferson, Leon and 4 more85 min
Apr 24, 3:35 PM CDTMesoscale DiscussionSPCDuval, Nassau85 min
Apr 23, 8:30 PM CDTTornado WatchSPCAdams, Amite, Claiborne, Copiah, Covington, Forrest and 15 more8 hr
Apr 23, 10:29 PM CDTMesoscale DiscussionSPCAmite, Forrest, George, Hancock, Lamar, Marion and 6 more2 hr

Nearby

Severe Thunderstorm Watches in Alabama, 2021Severe Thunderstorm Watches in Florida, 2021Severe Thunderstorm Watches in Mississippi, 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.