Alert archive / Alabama / Flash Flood Warnings in 2021

Flash Flood Warning 36, NWS Birmingham, AL

July 15, 2021Jefferson County, Alabama

NWS Birmingham, AL issued this flash flood warning at Jul 15, 2021, 8:09 PM CDT for Jefferson County, Alabama. It was in force for 2 hr. 1 report 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 15, 2021, 8:09 PM CDT (01:09 UTC)
Expired: Jul 15, 2021, 10:15 PM CDT
In force: 2 hr
Issued by: NWS Birmingham, AL
Area: Storm-based polygon
Flood severity: None

County Jefferson County, AL

The radar

The Birmingham radar (KBMX), 36 km from the middle of the area, began a volume at 01:10 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
Jul 15, 8:48 PM CDT	FLASH FLOOD	1 Ene Bjcc, AL	WATER RESCUE ONGOING AT THE INTERSECTION OF 31ST ST N AND 8TH AVE N.

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, 1.2 hours before the alert went out and 35 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: 1139 J/kg
Mixed-layer CIN: -11 J/kg
Mixed-layer LCL: 1445 m above ground
0-6 km bulk shear: 12 kt
0-1 km storm-relative helicity: 2 m²/s²
0-3 km storm-relative helicity: 0 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

206 
WGUS54 KBMX 160109
FFWBMX
ALC073-160315-
/O.NEW.KBMX.FF.W.0036.210716T0109Z-210716T0315Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Birmingham AL
809 PM CDT Thu Jul 15 2021

The National Weather Service in Birmingham has issued a

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

* Until 1015 PM CDT.

* At 809 PM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 1 and 2 inches of rain 
  have fallen. Additional rainfall amounts of 1 to 2 inches are 
  possible in the warned area. Flash flooding is ongoing or expected 
  to begin shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar.

  IMPACT...Flash flooding of small creeks and streams, urban
           areas, highways, streets and underpasses as well as
           other poor drainage and low-lying areas.

* Some locations that will experience flash flooding include...
  Birmingham, Vestavia Hills, Homewood, Mountain Brook, Regions 
  Field, U.A.B. Campus, Five Points South, B.j.c.c., Legion Field, 
  Samford University, Birmingham Southern College, Cahaba Heights, 
  The Summit, Vulcan Park, Birmingham Zoo, Highland Park Golf Course 
  and Rickwood Field.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Be aware of your surroundings and do not drive on flooded roads.

&&

LAT...LON 3348 8677 3344 8672 3344 8675 3346 8678
      3350 8687 3354 8688 3355 8684 3353 8677

FLASH FLOOD...RADAR INDICATED

$$

75/Linhares

2 follow-up statements

508 
WGUS74 KBMX 160218
FFSBMX

Flash Flood Statement
National Weather Service Birmingham AL
918 PM CDT Thu Jul 15 2021

ALC073-160315-
/O.CON.KBMX.FF.W.0036.000000T0000Z-210716T0315Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Jefferson AL-
918 PM CDT Thu Jul 15 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1015 PM CDT THIS 
EVENING FOR SOUTHEASTERN JEFFERSON COUNTY...

At 918 PM CDT, Doppler radar indicated that the thunderstorms have 
weakened over the warned area. But between 2 and 3 inches of rain 
have fallen in a short period of time. Runoff and flooding are still 
a likelihood for the next hour.

HAZARD...Flash flooding caused by thunderstorms.

SOURCE...Radar.

IMPACT...Flash flooding of small creeks and streams, urban areas,
         highways, streets and underpasses as well as other poor
         drainage and low-lying areas.

Some locations that will experience flash flooding include...
  Birmingham, Vestavia Hills, Homewood, Mountain Brook, Regions 
  Field, U.A.B. Campus, Five Points South, B.j.c.c., Legion Field, 
  Samford University, Birmingham Southern College, Cahaba Heights, 
  The Summit, Vulcan Park, Birmingham Zoo, Highland Park Golf Course 
  and Rickwood Field.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Be especially cautious at night when it is harder to recognize the 
dangers of flooding.

Please report observed flooding to local emergency services or law 
enforcement and request they pass this information to the National 
Weather Service when you can do so safely.

&&

LAT...LON 3348 8677 3344 8672 3344 8675 3346 8678
      3350 8687 3354 8688 3355 8684 3353 8677

FLASH FLOOD...RADAR INDICATED

$$

75/Linhares

132 
WGUS74 KBMX 160306
FFSBMX

Flash Flood Statement
National Weather Service Birmingham AL
1006 PM CDT Thu Jul 15 2021

ALC073-160316-
/O.EXP.KBMX.FF.W.0036.000000T0000Z-210716T0315Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Jefferson AL-
1006 PM CDT Thu Jul 15 2021

...FLASH FLOOD WARNING WILL EXPIRE AT 1015 PM CDT THIS EVENING FOR 
SOUTHEASTERN JEFFERSON COUNTY...

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

LAT...LON 3348 8677 3344 8672 3344 8675 3346 8678
      3350 8687 3354 8688 3355 8684 3353 8677

$$

75/Linhares

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 15, 7:21 PM CDT	Special Weather Statement	BMX	Lowndes	39 min
Jul 15, 7:29 PM CDT	Special Weather Statement	BMX	Jefferson	31 min
Jul 15, 8:00 PM CDT	Special Weather Statement	BMX	Jefferson	45 min
Jul 15, 8:28 PM CDT	Special Weather Statement	BMX	Jefferson	47 min
Jul 15, 9:41 PM CDT	Special Weather Statement	BMX	Marengo	34 min
Jul 15, 10:10 PM CDT	Areal Flood Advisory	BMX	Marengo	3 hr
Jul 16, 4:55 PM CDT	Special Weather Statement	BMX	Coosa	50 min
Jul 16, 4:56 PM CDT	Special Weather Statement	BMX	Autauga	49 min
Jul 16, 5:18 PM CDT	Special Weather Statement	BMX	Shelby	27 min

Nearby

Flash Flood Warnings in Alabama, 2021 Every 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.