Alert archive / Alabama / Flash Flood Warnings in 2020

Flash Flood Warning 21, NWS Birmingham, AL

June 29, 2020Jefferson County, Shelby County, Alabama

NWS Birmingham, AL issued this flash flood warning at Jun 29, 2020, 7:14 PM CDT for Jefferson County, Shelby County, Alabama. It was in force for 93 min. 3 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: Jun 29, 2020, 7:14 PM CDT (00:14 UTC)
Expired: Jun 29, 2020, 8:47 PM CDT
In force: 93 min
Issued by: NWS Birmingham, AL
Area: Storm-based polygon
Flood severity: None

Counties Jefferson County, AL, Shelby County, AL

The radar

The Birmingham radar (KBMX), 29 km from the middle of the area, began a volume at 00:14 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

Time	Report	Where	Remark
Jun 29, 7:15 PM CDT	FLASH FLOOD	Indian Springs Village, AL	WATER COVERING THE ROAD NEAR 119 AND CAHABA OAKS TRAIL.
Jun 29, 7:25 PM CDT	HEAVY RAIN 2.75	1 W Lake Purdy, AL	2.75 MEASURED RAINFALL WITH MINOR FLOODING ALSO REPORTED.
Jun 29, 7:33 PM CDT	FLASH FLOOD	1 S Mountain Brook, AL	SHADES CREEK NEAR OVERBROOK RD IS OVER ITS BANKS.

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 00:00Z, 0.2 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 1187 J/kg
Mixed-layer CIN: -30 J/kg
Mixed-layer LCL: 1416 m above ground
0-6 km bulk shear: 20 kt
0-1 km storm-relative helicity: 44 m²/s²
0-3 km storm-relative helicity: 47 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 1.3

Open this sounding in Storm Lab

The text

As transmitted.

988 
WGUS54 KBMX 300014
FFWBMX
ALC073-117-300315-
/O.NEW.KBMX.FF.W.0021.200630T0014Z-200630T0315Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Birmingham AL
714 PM CDT Mon Jun 29 2020

The National Weather Service in Birmingham has issued a

* Flash Flood Warning for...
  Southeastern Jefferson County in central Alabama...
  North Central Shelby County in central Alabama...

* Until 1015 PM CDT.

* At 714 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 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...
  Southern Birmingham, Hoover, Vestavia Hills, Homewood, Pelham, 
  Mountain Brook, Irondale, Leeds, Indian Springs Village, Brook 
  Highland, The Summit, Cahaba Heights, Meadowbrook, Inverness, Lake 
  Purdy, Greystone, Fowler Lake, Mount Laurel, Samford University 
  and Five Points South.

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 3336 8682 3348 8687 3357 8657 3352 8649
      3329 8678

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...0.5-2 INCHES IN 3 HOURS 

$$

40/Sizemore

1 follow-up statement

736 
WGUS74 KBMX 300147
FFSBMX

Flash Flood Statement
National Weather Service Birmingham AL
847 PM CDT Mon Jun 29 2020

ALC073-117-300157-
/O.CAN.KBMX.FF.W.0021.000000T0000Z-200630T0315Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Jefferson AL-Shelby AL-
847 PM CDT Mon Jun 29 2020

...FLASH FLOOD WARNING FOR SOUTHEASTERN JEFFERSON AND NORTH CENTRAL 
SHELBY COUNTIES HAS BEEN REPLACED WITH AN AREAL FLOOD WARNING...

The heavy rain has ended and flood waters are receding. Flooding is 
no longer expected to pose a threat. Please continue to heed 
remaining road closures.

LAT...LON 3336 8682 3348 8687 3357 8657 3352 8649
      3329 8678

$$

40/Sizemore

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 30, 6:09 AM CDT	Special Weather Statement	BMX	Marion	51 min
Jun 30, 7:48 AM CDT	Special Weather Statement	BMX	Marion	27 min
Jun 30, 8:17 AM CDT	Special Weather Statement	BMX	Marion	28 min
Jun 30, 11:29 AM CDT	Special Weather Statement	BMX	Randolph	61 min
Jun 30, 12:57 PM CDT	Special Weather Statement	BMX	Calhoun	33 min
Jun 30, 1:27 PM CDT	Special Weather Statement	BMX	Autauga	33 min
Jun 30, 1:58 PM CDT	Special Weather Statement	BMX	Coosa, Elmore	32 min
Jun 30, 2:23 PM CDT	Special Weather Statement	BMX	Tallapoosa	37 min
Jun 30, 2:29 PM CDT	Severe Thunderstorm Warning	BMX	Coosa, Tallapoosa	34 min
Jun 30, 2:54 PM CDT	Special Weather Statement	BMX	Tallapoosa	36 min
Jun 30, 2:59 PM CDT	Special Weather Statement	BMX	Russell	31 min
Jun 30, 3:22 PM CDT	Special Weather Statement	BMX	Randolph	23 min
Jun 30, 4:02 PM CDT	Special Weather Statement	BMX	Bibb	28 min
Jun 30, 4:18 PM CDT	Special Weather Statement	BMX	Chilton	42 min
Jun 30, 5:20 PM CDT	Special Weather Statement	BMX	Lowndes	25 min
Jun 30, 5:42 PM CDT	Special Weather Statement	BMX	Talladega	33 min
Jun 30, 5:50 PM CDT	Special Weather Statement	BMX	Lowndes	40 min
Jun 30, 6:24 PM CDT	Special Weather Statement	BMX	Talladega	36 min
Jun 30, 6:35 PM CDT	Special Weather Statement	BMX	Fayette	25 min

Nearby

Flash Flood Warnings in Alabama, 2020 Every flash flood warning in 2020

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.