Alert archive / Alabama / Flash Flood Warnings in 2021

Flash Flood Warning 35, NWS Huntsville, AL

September 17, 2021Colbert County, Lauderdale County, Alabama

NWS Huntsville, AL issued this flash flood warning at Sep 17, 2021, 5:11 PM CDT for Colbert County, Lauderdale County, Alabama. It was in force for 3 hr. 3 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: Sep 17, 2021, 5:11 PM CDT (22:11 UTC)
Expired: Sep 17, 2021, 8:15 PM CDT
In force: 3 hr
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), 116 km from the middle of the area, began a volume at 22:12 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
Sep 17, 5:44 PM CDT	FLASH FLOOD	6 N Cherokee, AL	FLASH FLOODING WAS REPORTED AT 6901 NORTH PIKE ROAD.
Sep 17, 6:54 PM CDT	FLASH FLOOD	2 Ne Cherokee, AL	FLASH FLOODING WAS REPORTED AT THE INTERSECTION OF MULBERRY LANE AND MOODY LANE.
Sep 17, 7:16 PM CDT	FLASH FLOOD	5 N Cherokee, AL	FLASH FLOODING WAS REPORTED AT THE INTERSECTION OF NORTH PIKE AND RIVERTON ROSE TRACE.

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

The nearest sounding before it

Little Rock, AR (KLZK), launched 12:00Z, 10.2 hours before the alert went out and 181 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: 344 J/kg
Mixed-layer CIN: -128 J/kg
Mixed-layer LCL: 591 m above ground
0-6 km bulk shear: 11 kt
0-1 km storm-relative helicity: 23 m²/s²
0-3 km storm-relative helicity: 31 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

530 
WGUS54 KHUN 172211
FFWHUN
ALC033-077-180115-
/O.NEW.KHUN.FF.W.0035.210917T2211Z-210918T0115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Huntsville AL
511 PM CDT Fri Sep 17 2021

The National Weather Service in Huntsville has issued a

* Flash Flood Warning for...
  Northwestern Colbert County in northwestern Alabama...
  Western Lauderdale County in northwestern Alabama...

* Until 815 PM CDT.

* At 511 PM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 1 and 3 inches of rain 
  have fallen. Additional rainfall amounts of 1 to 2 inches with 
  locally higher amounts 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...
  Waterloo and Wright.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3501 8807 3501 8788 3488 8783 3475 8790
      3480 8798 3485 8805

FLASH FLOOD...RADAR INDICATED

$$

KTW

2 follow-up statements

271 
WGUS74 KHUN 172340
FFSHUN

Flash Flood Statement
National Weather Service Huntsville AL
640 PM CDT Fri Sep 17 2021

ALC033-077-180115-
/O.CON.KHUN.FF.W.0035.000000T0000Z-210918T0115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Colbert AL-Lauderdale AL-
640 PM CDT Fri Sep 17 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 815 PM CDT THIS 
EVENING FOR NORTHWESTERN COLBERT AND WESTERN LAUDERDALE COUNTIES...

At 640 PM CDT, Doppler radar indicated thunderstorms producing heavy 
rain across the warned area. Between 2 and 4 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...
  Waterloo and Wright.

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 3501 8807 3501 8788 3488 8783 3475 8790
      3480 8798 3485 8805

FLASH FLOOD...RADAR INDICATED

$$

KTW

980 
WGUS74 KHUN 180012
FFSHUN

Flash Flood Statement
National Weather Service Huntsville AL
712 PM CDT Fri Sep 17 2021

ALC033-077-180115-
/O.CON.KHUN.FF.W.0035.000000T0000Z-210918T0115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Colbert AL-Lauderdale AL-
712 PM CDT Fri Sep 17 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 815 PM CDT THIS 
EVENING FOR NORTHWESTERN COLBERT AND WESTERN LAUDERDALE COUNTIES...

At 712 PM CDT, Doppler radar indicated thunderstorms producing heavy 
rain across the warned area. Between 3 and 6 inches of rain have 
fallen. Additional rainfall amounts up to 1 inch 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...
  Waterloo and Wright.

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 3501 8807 3501 8788 3488 8783 3475 8790
      3480 8798 3485 8805

FLASH FLOOD...RADAR INDICATED

$$

KTW

The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 17, 4:51 PM CDT	Special Weather Statement	HUN	Colbert	39 min
Sep 17, 6:27 PM CDT	Flash Flood Warning	HUN	Colbert, Lauderdale	93 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.