Alert archive / Alabama / Flash Flood Warnings in 2021

Flash Flood Warning 26, NWS Mobile, AL

May 12, 2021Clarke County, Washington County, Alabama

NWS Mobile, AL issued this flash flood warning at May 12, 2021, 3:46 AM CDT for Clarke County, Washington County, Alabama. It was in force for 4 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
May 12, 2021, 3:46 AM CDT (08:46 UTC)
Expired
May 12, 2021, 7:55 AM CDT
In force
4 hr
Issued by
NWS Mobile, AL
Area
Storm-based polygon
Flood severity
None

Counties Clarke County, AL, Washington County, AL

The radar

The Mobile radar (KMOB), 77 km from the middle of the area, began a volume at 08:47 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

Slidell Radar S, LA (KSIL), launched 00:00Z, 8.8 hours before the alert went out and 212 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, Slidell Radar S, LA at 00:00Z on 2021-05-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 618 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, Slidell Radar S, LA at 00:00Z on 2021-05-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 135 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
618 J/kg
Mixed-layer CIN
-59 J/kg
Mixed-layer LCL
924 m above ground
0-6 km bulk shear
32 kt
0-1 km storm-relative helicity
135 m²/s²
0-3 km storm-relative helicity
212 m²/s²
Significant tornado parameter
0.3
Supercell composite
4.7

Open this sounding in Storm Lab

The text

As transmitted.

772 
WGUS54 KMOB 120846
FFWMOB
ALC025-129-121445-
/O.NEW.KMOB.FF.W.0026.210512T0846Z-210512T1445Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mobile AL
346 AM CDT Wed May 12 2021

The National Weather Service in Mobile has issued a

* Flash Flood Warning for...
  South Central Clarke County in southwestern Alabama...
  Southeastern Washington County in southwestern Alabama...

* Until 945 AM CDT.

* At 346 AM 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...
  Carlton, Walker Springs and Choctaw Bluff.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3116 8797 3132 8800 3138 8787 3146 8777
      3134 8772 3133 8775 3136 8776 3133 8779
      3130 8776 3129 8779 3128 8778 3127 8780
      3128 8783 3123 8784 3123 8786 3120 8785
      3121 8787 3120 8787

FLASH FLOOD...RADAR INDICATED

$$
1 follow-up statement
382 
WGUS74 KMOB 121255
FFSMOB

Flash Flood Statement
National Weather Service Mobile AL
755 AM CDT Wed May 12 2021

ALC025-129-121305-
/O.CAN.KMOB.FF.W.0026.000000T0000Z-210512T1445Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Clarke AL-Washington AL-
755 AM CDT Wed May 12 2021

...FLASH FLOOD WARNING IS CANCELLED FOR SOUTH CENTRAL CLARKE AND 
SOUTHEASTERN WASHINGTON COUNTIES...

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

A Flash Flood Watch remains in effect until 600 PM CDT Wednesday for 
Portions of southwest Alabama. Portions of southeast Mississippi.

LAT...LON 3116 8797 3132 8800 3138 8787 3146 8777
      3134 8772 3133 8775 3136 8776 3133 8779
      3130 8776 3129 8779 3128 8778 3127 8780
      3128 8783 3123 8784 3123 8786 3120 8785
      3121 8787 3120 8787

$$

The office that day

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

IssuedProductOfficeCountiesLasted
May 12, 2:55 AM CDTSpecial Weather StatementMOBWashington65 min
May 12, 3:31 AM CDTSpecial Weather StatementMOBBaldwin, Mobile44 min
May 12, 4:06 AM CDTSpecial Weather StatementMOBBaldwin, Mobile54 min
May 12, 4:12 AM CDTAreal Flood AdvisoryMOBBaldwin, Mobile3 hr
May 12, 4:20 AM CDTSpecial Marine WarningMOB85 min
May 12, 4:41 AM CDTSpecial Marine WarningMOB94 min
May 12, 4:56 AM CDTSevere Thunderstorm WarningMOBMobile24 min
May 12, 5:01 AM CDTAreal Flood AdvisoryMOBBaldwin, Escambia3 hr
May 12, 5:04 AM CDTSpecial Weather StatementMOBBaldwin, Escambia86 min
May 12, 6:01 AM CDTSevere Thunderstorm WarningMOBConecuh, Covington, Escambia44 min
May 12, 6:24 AM CDTSpecial Marine WarningMOB96 min
May 12, 6:29 AM CDTSevere Thunderstorm WarningMOBCovington64 min
May 12, 6:35 AM CDTSpecial Marine WarningMOB55 min
May 12, 6:52 AM CDTAreal Flood AdvisoryMOBConecuh, Covington, Escambia3 hr
May 12, 6:56 AM CDTSevere Thunderstorm WarningMOBCovington, Crenshaw35 min
May 12, 7:18 AM CDTSpecial Marine WarningMOB87 min

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