Alert archive / Alabama / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 135, NWS Birmingham, AL

July 31, 2021Jefferson County, Shelby County, Alabama

NWS Birmingham, AL issued this severe thunderstorm warning at Jul 31, 2021, 3:34 PM CDT for Jefferson County, Shelby County, Alabama. It was in force for 41 min. 4 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Jul 31, 2021, 3:34 PM CDT (20:34 UTC)
Expired
Jul 31, 2021, 4:15 PM CDT
In force
41 min
Issued by
NWS Birmingham, AL
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

Counties Jefferson County, AL, Shelby County, AL

The radar

The Birmingham radar (KBMX), 21 km from the middle of the area, began a volume at 20:35 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 was reported inside it

TimeReportWhereRemark
Jul 31, 3:37 PM CDTTSTM WND DMG1 S Mountain Brook, ALTREE DOWN ON PINE RIDGE ROAD.
Jul 31, 3:40 PM CDTTSTM WND DMGConcord, ALA VERY LARGE PECAN TREE WAS BLOWN DOWN IN CONCORD.
Jul 31, 3:45 PM CDTTSTM WND DMG1 Sse Samford Universit, ALTREES WERE BLOWN DOWN ON SHADES CREEK ROAD, IN VESTAVIA HILLS.
Jul 31, 3:53 PM CDTTSTM WND DMG4 Ese Oak Mountain Stat, ALTWO TREES WERE BLOWN DOWN, NEAR CHELSEA.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Birmingham, AL (KBMX), launched 12:00Z, 8.6 hours before the alert went out and 20 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 2021-07-31Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1260 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Birmingham, AL at 12:00Z on 2021-07-31The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -46 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
1260 J/kg
Mixed-layer CIN
-102 J/kg
Mixed-layer LCL
1122 m above ground
0-6 km bulk shear
9 kt
0-1 km storm-relative helicity
-46 m²/s²
0-3 km storm-relative helicity
-36 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

051 
WUUS54 KBMX 312034
SVRBMX
ALC073-117-312115-
/O.NEW.KBMX.SV.W.0135.210731T2034Z-210731T2115Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Birmingham AL
334 PM CDT Sat Jul 31 2021

The National Weather Service in Birmingham has issued a

* Severe Thunderstorm Warning for...
  Central Shelby County in central Alabama...
  Southern Jefferson County in central Alabama...

* Until 415 PM CDT.

* At 334 PM CDT, severe thunderstorms were located along a line
  extending from Shops of Grand River to Birmingham to near North
  Johns, moving south at 30 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

  IMPACT...Expect damage to roofs, siding, and trees.

* Locations impacted include...
  Birmingham, Hoover, Vestavia Hills, Alabaster, Bessemer, Homewood,
  Pelham, Mountain Brook, Trussville, Helena, Hueytown, Irondale,
  Leeds, Fairfield, Chelsea, Pleasant Grove, Tarrant, Midfield,
  Brighton and Indian Springs Village.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 3356 8655 3353 8650 3334 8646 3323 8677
      3316 8700 3317 8702 3318 8703 3319 8702
      3325 8703 3325 8706 3328 8707 3329 8709
      3329 8712 3346 8716 3364 8658
TIME...MOT...LOC 2034Z 355DEG 26KT 3356 8660 3347 8687 3338 8716 

HAIL...<.75IN
WIND...60MPH
 
$$

87/GRANTHAM
3 follow-up statements
828 
WWUS54 KBMX 312048
SVSBMX

Severe Weather Statement
National Weather Service Birmingham AL
348 PM CDT Sat Jul 31 2021

ALC073-117-312115-
/O.CON.KBMX.SV.W.0135.000000T0000Z-210731T2115Z/
Shelby AL-Jefferson AL-
348 PM CDT Sat Jul 31 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 415 PM CDT
FOR CENTRAL SHELBY AND SOUTHEASTERN JEFFERSON COUNTIES...

At 348 PM CDT, severe thunderstorms were located along a line
extending from near Vandiver to Hoover to near North Johns, moving
southeast at 25 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Expect damage to roofs, siding, and trees.

Locations impacted include...
Birmingham, Hoover, Vestavia Hills, Alabaster, Bessemer, Homewood,
Pelham, Mountain Brook, Trussville, Helena, Hueytown, Irondale,
Leeds, Fairfield, Chelsea, Pleasant Grove, Midfield, Brighton, Indian
Springs Village and Lipscomb.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 3345 8716 3356 8680 3362 8657 3356 8655
      3353 8650 3334 8646 3323 8677 3316 8700
      3317 8702 3318 8703 3319 8702 3325 8703
      3325 8706 3328 8707 3329 8709 3329 8712
TIME...MOT...LOC 2048Z 335DEG 24KT 3350 8654 3341 8681 3332 8710 

HAIL...<.75IN
WIND...60MPH
 
$$

87/GRANTHAM
323 
WWUS54 KBMX 312101
SVSBMX

Severe Weather Statement
National Weather Service Birmingham AL
401 PM CDT Sat Jul 31 2021

ALC073-117-312115-
/O.CON.KBMX.SV.W.0135.000000T0000Z-210731T2115Z/
Shelby AL-Jefferson AL-
401 PM CDT Sat Jul 31 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 415 PM CDT
FOR CENTRAL SHELBY AND SOUTH CENTRAL JEFFERSON COUNTIES...

At 401 PM CDT, severe thunderstorms were located along a line
extending from near Westover to Pelham to near Splash Adventure,
moving south at 35 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Expect damage to roofs, siding, and trees.

Locations impacted include...
Hoover, Alabaster, Bessemer, Pelham, Helena, Chelsea, Indian Springs
Village, Harpersville, Westover, Oak Mountain State Park, Maylene,
Oak Mountain Amphitheater, Highland Lakes, Riverchase, Hoover
Metropolitan Stadium, Joe Tucker Park, Promenade Tannehill, Bent
Brook Golf Club, Siluria and McCalla.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 3330 8709 3335 8708 3336 8678 3344 8648
      3334 8646 3323 8677 3316 8700 3317 8702
      3318 8703 3319 8702 3325 8703 3325 8706
      3328 8707
TIME...MOT...LOC 2101Z 348DEG 32KT 3338 8649 3330 8677 3333 8702 

HAIL...<.75IN
WIND...60MPH
 
$$

87/GRANTHAM
835 
WWUS54 KBMX 312105
SVSBMX

Severe Weather Statement
National Weather Service Birmingham AL
405 PM CDT Sat Jul 31 2021

ALC073-117-312115-
/O.EXP.KBMX.SV.W.0135.000000T0000Z-210731T2115Z/
Shelby AL-Jefferson AL-
405 PM CDT Sat Jul 31 2021

...THE SEVERE THUNDERSTORM WARNING FOR CENTRAL SHELBY AND SOUTH
CENTRAL JEFFERSON COUNTIES WILL EXPIRE AT 415 PM CDT...
    
The storms which prompted the warning have moved out of the area.
Therefore, the warning will be allowed to expire.  However gusty
winds are still possible with these thunderstorms.

LAT...LON 3330 8709 3335 8708 3336 8678 3344 8648
      3334 8646 3323 8677 3316 8700 3317 8702
      3318 8703 3319 8702 3325 8703 3325 8706
      3328 8707
TIME...MOT...LOC 2105Z 355DEG 26KT 3336 8649 3328 8677 3331 8702 

$$

87/GRANTHAM

The office that day

Everything else NWS Birmingham, AL issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 30, 7:07 PM CDTSpecial Weather StatementBMXWinston38 min
Jul 30, 7:45 PM CDTSevere Thunderstorm WarningBMXCherokee, Etowah31 min
Jul 30, 7:51 PM CDTSevere Thunderstorm WarningBMXBlount39 min
Jul 31, 2:25 PM CDTSpecial Weather StatementBMXRussell50 min
Jul 31, 2:26 PM CDTSpecial Weather StatementBMXSt. Clair49 min
Jul 31, 2:28 PM CDTSpecial Weather StatementBMXChilton47 min
Jul 31, 2:29 PM CDTSpecial Weather StatementBMXDallas46 min
Jul 31, 2:44 PM CDTSpecial Weather StatementBMXShelby46 min
Jul 31, 2:47 PM CDTSpecial Weather StatementBMXJefferson, Walker43 min
Jul 31, 2:56 PM CDTSevere Thunderstorm WarningBMXBlount, Jefferson, Walker49 min
Jul 31, 3:04 PM CDTSevere Thunderstorm WarningBMXCalhoun, St. Clair, Talladega41 min
Jul 31, 3:09 PM CDTSpecial Weather StatementBMXChilton51 min
Jul 31, 3:11 PM CDTSpecial Weather StatementBMXRussell34 min
Jul 31, 3:23 PM CDTSpecial Weather StatementBMXCoosa37 min
Jul 31, 3:38 PM CDTSevere Thunderstorm WarningBMXChilton, Coosa, Shelby, Talladega52 min
Jul 31, 3:41 PM CDTSpecial Weather StatementBMXTalladega34 min
Jul 31, 3:57 PM CDTSpecial Weather StatementBMXShelby33 min
Jul 31, 3:59 PM CDTSpecial Weather StatementBMXElmore, Montgomery46 min
Jul 31, 4:12 PM CDTSpecial Weather StatementBMXClay, Randolph48 min
Jul 31, 4:18 PM CDTSpecial Weather StatementBMXChambers42 min
Jul 31, 4:22 PM CDTSpecial Weather StatementBMXTallapoosa53 min
Jul 31, 4:45 PM CDTSevere Thunderstorm WarningBMXTallapoosa45 min
Jul 31, 4:49 PM CDTSpecial Weather StatementBMXBibb41 min
Jul 31, 5:00 PM CDTSpecial Weather StatementBMXLee60 min
Jul 31, 6:36 PM CDTSpecial Weather StatementBMXBarbour, Russell39 min

Nearby

Severe Thunderstorm Warnings in Alabama, 2021Every severe thunderstorm warning 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.