Alert archive / Alabama / Flash Flood Warnings in 2021

Flash Flood Warning 19, NWS Birmingham, AL

May 4, 2021Jefferson County, St. Clair County, Shelby County, Alabama

NWS Birmingham, AL issued this flash flood warning at May 4, 2021, 1:39 PM CDT for Jefferson County, St. Clair County, Shelby County, Alabama. It was in force for 5 hr. 13 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
May 4, 2021, 1:39 PM CDT (18:39 UTC)
Expired
May 4, 2021, 7:00 PM CDT
In force
5 hr
Issued by
NWS Birmingham, AL
Area
Storm-based polygon
Flood severity
None

Counties Jefferson County, AL, Shelby County, AL, St. Clair County, AL

The radar

The Birmingham radar (KBMX), 28 km from the middle of the area, began a volume at 18:44 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
May 4, 1:55 PM CDTFLASH FLOOD1 W Cahaba Heights, ALDOLLY RIDGE ROAD IN CAHABA HEIGHTS FLOODED.
May 4, 5:03 PM CDTFLASH FLOOD1 Nne Helena, ALCORRECTS PREVIOUS TSTM WND DMG REPORT FROM 1 NNE HELENA. HELENA ROAD FLOODED WITH WATER FLOWING OVER THE ROAD NEAR THE QUARRY.
May 4, 5:25 PM CDTFLASH FLOODRiverchase Galleria, ALALL LANES OF HIGHWAY 31 AT HIGHWAY 150 ARE CLOSED DUE TO FLASH FLOODING.
May 4, 5:28 PM CDTFLASH FLOODJoe Tucker Park, ALFLOODING NEAR COUNTY ROADS 52 AND 95 IN HELENA.
May 4, 5:33 PM CDTFLASH FLOOD1 S Riverchase, ALFIRE DEPARTMENT REPORTING HOMES FLOODED ON NORRIDGE PLACE.
May 4, 5:33 PM CDTFLASH FLOOD2 W Alabaster, ALHIGHWAY 17 NORTHBOUND BETWEEN CEDAR GROVE PARKWAY AND HIGH GROVE PARKWAY IMPASSABLE.
May 4, 5:33 PM CDTFLASH FLOOD2 W Alabaster, ALWATER OVER THE ROADWAY AT FOX VALLEY FARMS ROAD NEAR BRIDGE.
May 4, 5:40 PM CDTFLASH FLOOD1 Nw Alabaster Veterans, AL1 LANE IMPASSABLE AT BUTLER ROAD AND BIG OAK DRIVE.
May 4, 5:50 PM CDTFLASH FLOOD1 N Hoover, ALPATTON CREEK OVERTOPPING THE BRIDGE AT SOUTHLAND DRIVE.
May 4, 5:54 PM CDTFLASH FLOOD2 Se Vestavia Hills, ALFLASH FLOODING IN THE 2400 BLOCK OF ACTON ROAD. LARGE ROCKS BEING WASHED INTO THE ROADWAY.
May 4, 6:00 PM CDTFLASH FLOOD2 Ese Vestavia Hills, ALHOMES FLOODED ON LESLIE ANN ROAD.
May 4, 6:30 PM CDTFLASH FLOOD1 Ne Maylene, ALBIG OAK DRIVE FLOODED.
May 4, 6:45 PM CDTFLASH FLOOD1 S Lake Purdy, ALFAST MOVING AND DEEP WATER RUNNING ACROSS HIGHWAY 119 NEAR LAKE PURDY.

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, 6.7 hours before the alert went out and 28 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 2021-05-04Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2158 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 2021-05-04The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 145 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
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

Open this sounding in Storm Lab

The text

As transmitted.

198 
WGUS54 KBMX 041839
FFWBMX
ALC073-115-117-042200-
/O.NEW.KBMX.FF.W.0019.210504T1839Z-210504T2200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Birmingham AL
139 PM CDT Tue May 4 2021

The National Weather Service in Birmingham has issued a

* Flash Flood Warning for...
  Southeastern Jefferson County in central Alabama...
  Southwestern St. Clair County in central Alabama...
  Central Shelby County in central Alabama...

* Until 500 PM CDT.

* At 139 PM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 1 and 2 inches of rain 
  have fallen. Flash flooding is ongoing or expected to begin 
  shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Doppler radar.

  IMPACT...Flooding of small creeks and streams, urban areas,
           highways, streets and underpasses as well as other
           drainage and low lying areas.

* Some locations that will experience flash flooding include...
  Hoover, Vestavia Hills, Alabaster, Bessemer, Pelham, Mountain 
  Brook, Helena, Pell City, Leeds, Moody, Chelsea, Indian Springs 
  Village, Vincent, Harpersville, Westover, Meadowbrook, Highland 
  Lakes, Inverness, Oak Mountain State Park and Fowler Lake.

Additional rainfall amounts of 1 to 2 inches are possible in the 
warned area.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

Excessive runoff from heavy rainfall will cause flooding of small 
creeks and streams, urban areas, highways, streets and underpasses 
as well as other drainage areas and low lying spots.

&&

LAT...LON 3329 8709 3356 8654 3354 8646 3354 8619
      3352 8623 3349 8624 3349 8626 3351 8626
      3351 8628 3346 8630 3339 8638 3311 8697
      3315 8698 3317 8703 3325 8703 3325 8706

FLASH FLOOD...RADAR INDICATED

$$

40/Sizemore
1 follow-up statement
476 
WGUS54 KBMX 042128
FFWBMX
ALC073-115-117-050000-
/O.EXT.KBMX.FF.W.0019.000000T0000Z-210505T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Birmingham AL
428 PM CDT Tue May 4 2021

The National Weather Service in Birmingham has extended the

* Flash Flood Warning for...
  Southeastern Jefferson County in central Alabama...
  Southwestern St. Clair County in central Alabama...
  Central Shelby County in central Alabama...

* Until 700 PM CDT.

* At 428 PM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 2 and 3 inches of rain 
  have fallen. Flash flooding is already occurring.

  HAZARD...Life threatening flash flooding. Thunderstorms
           producing flash flooding.

  SOURCE...Doppler radar.

  IMPACT...Life threatening flash flooding of creeks and streams,
           urban areas, highways, streets and underpasses.

* Some locations that will experience flash flooding include...
  Hoover, Vestavia Hills, Alabaster, Bessemer, Pelham, Mountain 
  Brook, Helena, Pell City, Leeds, Moody, Chelsea, Indian Springs 
  Village, Vincent, Harpersville, Westover, Meadowbrook, Highland 
  Lakes, Inverness, Oak Mountain State Park and Fowler Lake.

Additional rainfall amounts of 1 to 2 inches are possible in the 
warned area.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

Excessive runoff from heavy rainfall will cause flooding of small 
creeks and streams, urban areas, highways, streets and underpasses 
as well as other drainage areas and low lying spots.

&&

LAT...LON 3329 8709 3356 8654 3354 8646 3354 8619
      3352 8623 3349 8624 3349 8626 3351 8626
      3351 8628 3346 8630 3339 8638 3311 8697
      3315 8698 3317 8703 3325 8703 3325 8706

FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE

$$

40/Sizemore

The office that day

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

IssuedProductOfficeCountiesLasted
May 3, 7:02 PM CDTSevere Thunderstorm WarningBMXElmore, Montgomery43 min
May 3, 7:13 PM CDTSevere Thunderstorm WarningBMXBibb, Chilton, Perry32 min
May 3, 7:25 PM CDTFlash Flood WarningBMXAutauga, Elmore, Macon, Montgomery5 hr
May 3, 7:29 PM CDTAreal Flood AdvisoryBMXChambers, Lee, Macon, Tallapoosa2 hr
May 3, 7:40 PM CDTSevere Thunderstorm WarningBMXElmore, Macon, Montgomery47 min
May 3, 7:46 PM CDTSpecial Weather StatementBMXChilton44 min
May 3, 8:30 PM CDTSpecial Weather StatementBMXLee, Macon45 min
May 3, 8:36 PM CDTSpecial Weather StatementBMXChilton39 min
May 3, 8:51 PM CDTAreal Flood AdvisoryBMXBibb, Chilton, Perry3 hr
May 3, 8:59 PM CDTSpecial Weather StatementBMXRussell46 min
May 3, 9:31 PM CDTSpecial Weather StatementBMXShelby59 min
May 4, 7:27 AM CDTSpecial Weather StatementBMXMarion48 min
May 4, 7:57 AM CDTSpecial Weather StatementBMXLamar, Marion48 min
May 4, 9:07 AM CDTSevere Thunderstorm WarningBMXWinston38 min
May 4, 10:26 AM CDTSevere Thunderstorm WarningBMXBlount23 min
May 4, 10:59 AM CDTSpecial Weather StatementBMXWalker31 min
May 4, 11:00 AM CDTAreal Flood AdvisoryBMXFayette, Lamar, Walker3 hr
May 4, 11:06 AM CDTAreal Flood AdvisoryBMXBlount, Calhoun, Cherokee, Etowah, St. Clair3 hr
May 4, 11:12 AM CDTTornado WarningBMXFayette, Tuscaloosa21 min
May 4, 11:25 AM CDTSevere Thunderstorm WarningBMXJefferson, Walker50 min
May 4, 11:45 AM CDTAreal Flood AdvisoryBMXJefferson2 hr
May 4, 11:49 AM CDTSevere Thunderstorm WarningBMXBlount, Jefferson, St. Clair26 min
May 4, 12:03 PM CDTFlash Flood WarningBMXBlount, Etowah, St. Clair117 min
May 4, 12:10 PM CDTFlash Flood WarningBMXJefferson7 hr
May 4, 12:14 PM CDTSevere Thunderstorm WarningBMXCalhoun, St. Clair, Talladega46 min
May 4, 12:17 PM CDTSevere Thunderstorm WarningBMXJefferson, St. Clair, Shelby28 min
May 4, 12:35 PM CDTFlash Flood WarningBMXCalhoun, Etowah, St. Clair, Talladega3 hr
May 4, 12:56 PM CDTSevere Thunderstorm WarningBMXCalhoun, Cherokee, Cleburne, Talladega64 min
May 4, 1:15 PM CDTSevere Thunderstorm WarningBMXJefferson, Shelby30 min
May 4, 1:25 PM CDTTornado WarningBMXCleburne24 min
May 4, 2:07 PM CDTAreal Flood WarningBMXBlount, Calhoun, Cherokee, Etowah, St. Clair6 hr
May 4, 2:54 PM CDTAreal Flood AdvisoryBMXClay, Cleburne, Randolph, Shelby, Talladega3 hr
May 4, 3:50 PM CDTSevere Thunderstorm WarningBMXSumter55 min
May 4, 4:01 PM CDTFlash Flood WarningBMXShelby, Talladega3 hr
May 4, 4:05 PM CDTFlash Flood WarningBMXBibb, Tuscaloosa3 hr
May 4, 4:13 PM CDTSevere Thunderstorm WarningBMXTuscaloosa29 min
May 4, 4:20 PM CDTSevere Thunderstorm WarningBMXGreene55 min
May 4, 4:30 PM CDTSevere Thunderstorm WarningBMXHale, Marengo63 min
May 4, 4:45 PM CDTSpecial Weather StatementBMXWalker, Winston30 min
May 4, 5:00 PM CDTSevere Thunderstorm WarningBMXBibb, Chilton, Dallas, Perry75 min
May 4, 5:17 PM CDTFlash Flood Warning EmergencyCatastrophic damage threatBMXJefferson, Shelby3 hr
May 4, 5:29 PM CDTSevere Thunderstorm WarningBMXAutauga, Chilton, Lowndes76 min
May 4, 5:30 PM CDTTornado WarningBMXChilton, Perry30 min
May 4, 5:38 PM CDTTornado WarningBMXShelby12 min
May 4, 5:54 PM CDTSevere Thunderstorm WarningBMXCoosa50 min
May 4, 5:59 PM CDTSevere Thunderstorm WarningBMXElmore61 min
May 4, 6:07 PM CDTSevere Thunderstorm WarningBMXMontgomery68 min
May 4, 6:19 PM CDTSevere Thunderstorm WarningBMXTallapoosa56 min
May 4, 6:24 PM CDTTornado WarningBMXElmore, Montgomery13 min
May 4, 6:37 PM CDTSevere Thunderstorm WarningBMXBullock, Macon, Pike83 min
May 4, 6:41 PM CDTSevere Thunderstorm WarningBMXChambers, Lee61 min
May 4, 6:48 PM CDTRiver Flood WarningBMXBibb, Jefferson, Shelby22 hr

Nearby

Flash Flood Warnings in Alabama, 2021Every flash flood 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.