Alert archive / Alabama / Flash Flood Warnings in 2021

Flash Flood Warning 49, NWS Mobile, AL

August 19, 2021Choctaw County, Clarke County, Washington County, Alabama

NWS Mobile, AL issued this flash flood warning at Aug 19, 2021, 8:35 PM CDT for Choctaw County, Clarke County, Washington County, Alabama. It was in force for 3 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Aug 19, 2021, 8:35 PM CDT (01:35 UTC)
Expired: Aug 19, 2021, 11:30 PM CDT
In force: 3 hr
Issued by: NWS Mobile, AL
Area: Storm-based polygon
Flood severity: None

Counties Choctaw County, AL, Clarke County, AL, Washington County, AL

The radar

The Mobile radar (KMOB), 106 km from the middle of the area, began a volume at 01:35 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.

The nearest sounding before it

Jackson, MS (KJAN), launched 00:00Z, 1.6 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-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: 413 J/kg
Mixed-layer CIN: -62 J/kg
Mixed-layer LCL: 1178 m above ground
0-6 km bulk shear: 12 kt
0-1 km storm-relative helicity: 82 m²/s²
0-3 km storm-relative helicity: 94 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

581 
WGUS54 KMOB 200135
FFWMOB
ALC023-025-129-200745-
/O.NEW.KMOB.FF.W.0049.210820T0135Z-210820T0745Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mobile AL
835 PM CDT Thu Aug 19 2021

The National Weather Service in Mobile has issued a

* Flash Flood Warning for...
  Southwestern Choctaw County in southwestern Alabama...
  Central Clarke County in southwestern Alabama...
  Northern Washington County in southwestern Alabama...

* Until 245 AM CDT Friday.

* At 835 PM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 2 and 4 inches of rain 
  have fallen. The expected rainfall rate is 1 to 2 inches in 1 
  hour. Additional rainfall amounts of 1 to 3 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...
  Jackson, Grove Hill, Saint Stephens, Leroy, Millry, Coffeeville, 
  Frankville, Salitpa, Bigbee, Tattlersville, Mays Crossroads, 
  Silver Cross, Bladon Springs, Winn, Koenton, McVay, Jordan, Yarbo, 
  Toddtown and Loper.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3176 8846 3176 8771 3149 8773 3149 8791
      3149 8845

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...1-2 INCHES IN 1 HOUR

$$

MM

1 follow-up statement

775 
WGUS74 KMOB 200430
FFSMOB

Flash Flood Statement
National Weather Service Mobile AL
1130 PM CDT Thu Aug 19 2021

ALC023-025-129-200440-
/O.CAN.KMOB.FF.W.0049.000000T0000Z-210820T0745Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Choctaw AL-Clarke AL-Washington AL-
1130 PM CDT Thu Aug 19 2021

...FLASH FLOOD WARNING IS CANCELLED FOR SOUTHWESTERN CHOCTAW, 
CENTRAL CLARKE AND NORTHERN WASHINGTON COUNTIES...

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

LAT...LON 3176 8846 3176 8771 3149 8773 3149 8791
      3149 8845

$$

MM

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 19, 7:38 PM CDT	Severe Thunderstorm Warning	MOB	Clarke, Washington	52 min
Aug 19, 7:46 PM CDT	Areal Flood Advisory	MOB	Choctaw, Clarke, Washington	3 hr
Aug 19, 8:19 PM CDT	Special Weather Statement	MOB	Clarke	56 min
Aug 19, 8:52 PM CDT	Areal Flood Advisory	MOB	Clarke	3 hr
Aug 20, 12:38 PM CDT	Special Marine Warning	MOB		82 min
Aug 20, 12:42 PM CDT	Special Weather Statement	MOB	Baldwin	48 min
Aug 20, 2:39 PM CDT	Special Marine Warning	MOB		96 min
Aug 20, 2:40 PM CDT	Areal Flood Advisory	MOB	Escambia	3 hr
Aug 20, 3:08 PM CDT	Areal Flood Advisory	MOB	Baldwin, Escambia, Monroe	112 min
Aug 20, 3:21 PM CDT	Areal Flood Advisory	MOB	Conecuh, Escambia	114 min
Aug 20, 3:41 PM CDT	Areal Flood Advisory	MOB	Clarke, Washington	2 hr
Aug 20, 4:19 PM CDT	Severe Thunderstorm Warning	MOB	Mobile	41 min
Aug 20, 4:27 PM CDT	Areal Flood Advisory	MOB	Clarke, Monroe	2 hr
Aug 20, 5:23 PM CDT	Areal Flood Advisory	MOB	Mobile	4 hr
Aug 20, 6:02 PM CDT	Areal Flood Advisory	MOB	Mobile	3 hr
Aug 20, 6:12 PM CDT	Special Marine Warning	MOB		48 min
Aug 20, 6:47 PM CDT	Areal Flood Advisory	MOB	Baldwin	3 hr

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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.