Alert archive / Alabama / Flash Flood Warnings in 2021

Flash Flood Warning 49, NWS Huntsville, AL

October 6, 2021Jackson County, Marshall County, Alabama

NWS Huntsville, AL issued this flash flood warning at Oct 6, 2021, 10:50 PM CDT for Jackson County, Marshall County, Alabama. It was in force for 2 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
Oct 6, 2021, 10:50 PM CDT (03:50 UTC)
Expired
Oct 7, 2021, 1:00 AM CDT
In force
2 hr
Issued by
NWS Huntsville, AL
Area
Storm-based polygon
Flood severity
None

Counties Jackson County, AL, Marshall County, AL

The radar

The Northeast Alabama radar (KHTX), 54 km from the middle of the area, began a volume at 03:52 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

Birmingham, AL (KBMX), launched 00:00Z, 3.8 hours before the alert went out and 152 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 00:00Z on 2021-10-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1415 joules per kilogram.LCLEL10008507005003002001001 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 00:00Z on 2021-10-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 62 square meters per square second.1939587897Sfc1 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
1415 J/kg
Mixed-layer CIN
-6 J/kg
Mixed-layer LCL
923 m above ground
0-6 km bulk shear
29 kt
0-1 km storm-relative helicity
62 m²/s²
0-3 km storm-relative helicity
123 m²/s²
Significant tornado parameter
0.4
Supercell composite
2.8

Open this sounding in Storm Lab

The text

As transmitted.

430 
WGUS54 KHUN 070350
FFWHUN
ALC071-095-070600-
/O.NEW.KHUN.FF.W.0049.211007T0350Z-211007T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Huntsville AL
1050 PM CDT Wed Oct 6 2021

The National Weather Service in Huntsville has issued a

* Flash Flood Warning for...
  Southwestern Jackson County in northeastern Alabama...
  Northeastern Marshall County in northeastern Alabama...

* Until 100 AM CDT.

* At 1050 PM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across 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...
  Albertville, Scottsboro, Guntersville, Grant, Woodville, Langston, 
  Columbus City, Lake Guntersville St Park, Hustleville and Rabbit 
  Town.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

&&

LAT...LON 3460 8629 3465 8623 3465 8614 3455 8601
      3443 8611 3440 8611 3440 8612 3438 8611
      3429 8613 3423 8621 3426 8629

FLASH FLOOD...RADAR INDICATED

$$

MA
1 follow-up statement
873 
WGUS74 KHUN 070553 RRA
FFSHUN

Flash Flood Statement
National Weather Service Huntsville AL
1253 AM CDT Thu Oct 7 2021

ALC071-095-070603-
/O.EXP.KHUN.FF.W.0049.000000T0000Z-211007T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Jackson AL-Marshall AL-
1253 AM CDT Thu Oct 7 2021

...FLASH FLOOD WARNING WILL EXPIRE AT 1 AM CDT EARLY THIS MORNING 
FOR SOUTHWESTERN JACKSON AND NORTHEASTERN MARSHALL COUNTIES...

The heavy rain has ended. A new Areal Flood Warning has replaced 
this as residual flooding is still ongoing. Please continue to heed 
remaining road closures.

A Flash Flood Watch remains in effect until 700 AM CDT Thursday for 
portions of Alabama and southern middle Tennessee.

LAT...LON 3460 8629 3465 8623 3465 8614 3455 8601
      3443 8611 3440 8611 3440 8612 3438 8611
      3429 8613 3423 8621 3426 8629

$$

GH

The office that day

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

IssuedProductOfficeCountiesLasted
Oct 6, 7:36 PM CDTSpecial Weather StatementHUNMarshall39 min
Oct 6, 8:13 PM CDTSpecial Weather StatementHUNMarshall47 min
Oct 6, 8:36 PM CDTFlash Flood WarningHUNCullman4 hr
Oct 6, 9:02 PM CDTSpecial Weather StatementHUNMadison43 min
Oct 7, 12:50 AM CDTAreal Flood WarningHUNCullman, Jackson, Madison, Marshall8 hr
Oct 7, 8:57 AM CDTAreal Flood WarningHUNCullman111 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.