Alert archive / Alabama / Flash Flood Warnings in 2021

Flash Flood Warning 29, NWS Huntsville, AL

August 13, 2021Colbert County, Lauderdale County, Alabama

NWS Huntsville, AL issued this flash flood warning at Aug 13, 2021, 5:01 PM CDT for Colbert County, Lauderdale County, Alabama. It was in force for 119 min. 2 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
Aug 13, 2021, 5:01 PM CDT (22:01 UTC)
Expired
Aug 13, 2021, 7:00 PM CDT
In force
119 min
Issued by
NWS Huntsville, AL
Area
Storm-based polygon
Flood severity
None

Counties Colbert County, AL, Lauderdale County, AL

The radar

The Columbus AFB radar (KGWX), 121 km from the middle of the area, began a volume at 22:01 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

TimeReportWhereRemark
Aug 13, 5:11 PM CDTFLASH FLOOD1 Nnw Tuscumbia, ALFLOODING REPORTED ACROSS WHEELER AVE AND BLACKWELL RD.
Aug 13, 5:31 PM CDTFLASH FLOOD1 Nne Tuscumbia, ALFLOODING REPORTED AT THE INTERSECTION OF N CAVE STREET AND N COMMONS STREET. PHOTOS ON SOCIAL MEDIA SHOW CARS STALLED IN FLOODWATERS ACROSS THE AREA.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Nashville Metro, TN (KBNA), launched 12:00Z, 10.0 hours before the alert went out and 173 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, Nashville Metro, TN at 12:00Z on 2021-08-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1072 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, Nashville Metro, TN at 12:00Z on 2021-08-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 43 square meters per square second.1939Sfc1 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
1072 J/kg
Mixed-layer CIN
-119 J/kg
Mixed-layer LCL
1013 m above ground
0-6 km bulk shear
11 kt
0-1 km storm-relative helicity
43 m²/s²
0-3 km storm-relative helicity
54 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

168 
WGUS54 KHUN 132201
FFWHUN
ALC033-077-140000-
/O.NEW.KHUN.FF.W.0029.210813T2201Z-210814T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Huntsville AL
501 PM CDT Fri Aug 13 2021

The National Weather Service in Huntsville has issued a

* Flash Flood Warning for...
  Southeastern Colbert County in northwestern Alabama...
  Central Lauderdale County in northwestern Alabama...

* Until 700 PM CDT.

* At 501 PM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 1 and 2 inches of rain 
  have fallen. The expected rainfall rate is 1 to 3 inches in 1 
  hour. 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...
  Florence, Muscle Shoals, Sheffield, Tuscumbia, Killen, 
  Littleville, St. Florian, Northwest Alabama Regional Airport, Ford 
  City and Colbert Heights.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3490 8759 3488 8751 3485 8745 3481 8747
      3458 8763 3465 8780

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...1-3 INCHES IN 1 HOUR

$$

RSB
2 follow-up statements
058 
WGUS74 KHUN 132318
FFSHUN

Flash Flood Statement
National Weather Service Huntsville AL
618 PM CDT Fri Aug 13 2021

ALC033-077-140000-
/O.CON.KHUN.FF.W.0029.000000T0000Z-210814T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Colbert AL-Lauderdale AL-
618 PM CDT Fri Aug 13 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 7 PM CDT THIS EVENING 
FOR SOUTHEASTERN COLBERT AND CENTRAL LAUDERDALE COUNTIES...

At 618 PM CDT, Doppler radar indicated thunderstorms that produced 
very heavy rainfall earlier have shifted east of the area. Runoff 
from the recent rains will keep a risk of flash flooding going into 
the early evening. Between 1 and 3 inches of rain have fallen, and 
up to 1 additional inch is possible over 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...
  Florence, Muscle Shoals, Sheffield, Tuscumbia, Killen, 
  Littleville, St. Florian, Northwest Alabama Regional Airport, Ford 
  City and Colbert Heights.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3490 8759 3488 8751 3485 8745 3481 8747
      3458 8763 3465 8780

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...1-3 INCHES IN 1 HOUR

$$

RSB
046 
WGUS74 KHUN 132353
FFSHUN

Flash Flood Statement
National Weather Service Huntsville AL
653 PM CDT Fri Aug 13 2021

ALC033-077-140003-
/O.EXP.KHUN.FF.W.0029.000000T0000Z-210814T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Colbert AL-Lauderdale AL-
653 PM CDT Fri Aug 13 2021

...FLASH FLOOD WARNING WILL EXPIRE AT 7 PM CDT THIS EVENING FOR 
SOUTHEASTERN COLBERT AND CENTRAL LAUDERDALE COUNTIES...

Flooding is no longer expected to pose a threat. Please continue to 
heed remaining road closures.

LAT...LON 3490 8759 3488 8751 3485 8745 3481 8747
      3458 8763 3465 8780

$$

RSB

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 13, 12:05 PM CDTSpecial Weather StatementHUNDeKalb40 min
Aug 13, 12:52 PM CDTSpecial Weather StatementHUNDeKalb38 min
Aug 13, 3:23 PM CDTSpecial Weather StatementHUNMadison37 min
Aug 13, 4:35 PM CDTSpecial Weather StatementHUNLauderdale25 min
Aug 13, 4:39 PM CDTSpecial Weather StatementHUNLimestone36 min
Aug 13, 5:12 PM CDTSpecial Weather StatementHUNMorgan48 min
Aug 13, 5:18 PM CDTSpecial Weather StatementHUNFranklin42 min
Aug 13, 5:38 PM CDTFlash Flood WarningHUNLawrence, Limestone, Morgan2 hr
Aug 13, 5:44 PM CDTSpecial Weather StatementHUNCullman46 min
Aug 13, 5:57 PM CDTSpecial Weather StatementHUNLimestone63 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.