Alert archive / Alabama / Flash Flood Warnings in 2021

Flash Flood Warning 22, NWS Huntsville, AL

June 19, 2021DeKalb County, Alabama

NWS Huntsville, AL issued this flash flood warning at Jun 19, 2021, 10:35 PM CDT for DeKalb County, Alabama. It was in force for 5 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
Jun 19, 2021, 10:35 PM CDT (03:35 UTC)
Expired
Jun 20, 2021, 3:30 AM CDT
In force
5 hr
Issued by
NWS Huntsville, AL
Area
Storm-based polygon
Damage threat
Considerable
Flood severity
None

County DeKalb County, AL

The radar

The Northeast Alabama radar (KHTX), 68 km from the middle of the area, began a volume at 03:39 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

Peachtre/Fal Fld, GA (KFFC), launched 00:00Z, 3.6 hours before the alert went out and 159 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, Peachtre/Fal Fld, GA at 00:00Z on 2021-06-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 252 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Peachtre/Fal Fld, GA at 00:00Z on 2021-06-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 340 square meters per square second.193958Sfc1 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
252 J/kg
Mixed-layer CIN
-116 J/kg
Mixed-layer LCL
651 m above ground
0-6 km bulk shear
37 kt
0-1 km storm-relative helicity
340 m²/s²
0-3 km storm-relative helicity
516 m²/s²
Significant tornado parameter
0.4
Supercell composite
4.7

Open this sounding in Storm Lab

The text

As transmitted.

601 
WGUS54 KHUN 200335
FFWHUN
ALC049-200830-
/O.NEW.KHUN.FF.W.0022.210620T0335Z-210620T0830Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Huntsville AL
1035 PM CDT Sat Jun 19 2021

The National Weather Service in Huntsville has issued a

* Flash Flood Warning for...
  Southeastern DeKalb County in northeastern Alabama...

* Until 330 AM CDT.

* At 1035 PM CDT, emergency management reported portions of highway 
  35 and Airport Road closed. Between 4 and 7 inches of rain have 
  fallen. Flash flooding is already occurring.

  HAZARD...Life threatening flash flooding. Heavy rain producing
           flash flooding.

  SOURCE...Emergency management.

  IMPACT...Life threatening flash flooding of creeks and streams,
           urban areas, highways, streets and underpasses.

* Some locations that will experience flash flooding include...
  Fort Payne, Rainsville, Fyffe, Valley Head, Hammondville, Pine 
  Ridge, Collbran, Dog Town, Adamsburg, Lebanon, Little River Canyon 
  NP, Guest, Peeks Corner and Desoto State Park.

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 3431 8571 3431 8595 3447 8587 3454 8564
      3454 8552 3452 8551 3453 8552 3452 8552
      3450 8555 3450 8556 3449 8556 3447 8558
      3447 8557 3446 8558 3444 8558 3443 8559
      3440 8563 3439 8562

FLASH FLOOD...OBSERVED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
EXPECTED RAINFALL...0.75-2 INCHES IN 1 HOUR 

$$

KTW
2 follow-up statements
653 
WGUS74 KHUN 200348
FFSHUN

Flash Flood Statement
National Weather Service Huntsville AL
1048 PM CDT Sat Jun 19 2021

ALC049-200830-
/O.CON.KHUN.FF.W.0022.000000T0000Z-210620T0830Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
DeKalb AL-
1048 PM CDT Sat Jun 19 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 330 AM CDT SUNDAY FOR 
SOUTHEASTERN DEKALB COUNTY...

At 1048 PM CDT, emergency management reported portions of highway 35 
and Airport road closed. In addition, a car was stalled in high 
water at the intersection of highway 35 and Airport road. Between 4 
and 7 inches of rain have fallen. Flash flooding is already 
occurring.

HAZARD...Life threatening flash flooding. Heavy rain producing
         flash flooding.

SOURCE...Emergency management.

IMPACT...Life threatening flash flooding of creeks and streams,
         urban areas, highways, streets and underpasses.

Some locations that will experience flash flooding include...
  Fort Payne, Rainsville, Fyffe, Valley Head, Hammondville, Pine 
  Ridge, Collbran, Dog Town, Adamsburg, Lebanon, Little River Canyon 
  NP, Guest, Peeks Corner and Desoto State Park.

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 3431 8571 3431 8595 3447 8587 3454 8564
      3454 8552 3452 8551 3453 8552 3452 8552
      3450 8555 3450 8556 3449 8556 3447 8558
      3447 8557 3446 8558 3444 8558 3443 8559
      3440 8563 3439 8562

FLASH FLOOD...OBSERVED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
EXPECTED RAINFALL...0.75-2 INCHES IN 1 HOUR 

$$

KTW
319 
WGUS74 KHUN 200734
FFSHUN

Flash Flood Statement
National Weather Service Huntsville AL
234 AM CDT Sun Jun 20 2021

ALC049-200830-
/O.CON.KHUN.FF.W.0022.000000T0000Z-210620T0830Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
DeKalb AL-
234 AM CDT Sun Jun 20 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 330 AM CDT EARLY THIS 
MORNING FOR SOUTHEASTERN DEKALB COUNTY...

At 234 AM CDT, Doppler radar and automated rain gauges indicated 
that heavy rain has fallen across the warned area. Between 4 and 7 
inches of rain have fallen. Flash flooding is already occurring.

HAZARD...Life threatening flash flooding. Heavy rain producing
         flash flooding.

SOURCE...Doppler radar and automated gauges.

IMPACT...Life threatening flash flooding of creeks and streams,
         urban areas, highways, streets and underpasses.

Some locations that will experience flash flooding include...
  Fort Payne, Rainsville, Fyffe, Valley Head, Hammondville, Pine 
  Ridge, Collbran, Dog Town, Adamsburg, Lebanon, Little River Canyon 
  NP, Guest, Peeks Corner and Desoto State Park.

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 3431 8571 3431 8595 3447 8587 3454 8564
      3454 8552 3452 8551 3453 8552 3452 8552
      3450 8555 3450 8556 3449 8556 3447 8558
      3447 8557 3446 8558 3444 8558 3443 8559
      3440 8563 3439 8562

FLASH FLOOD...RADAR AND GAUGE INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
EXPECTED RAINFALL...0.25-0.75 INCHES IN 1 HOUR 

$$

70/DD

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 19, 9:22 PM CDTFlash Flood WarningHUNDeKalb, Marshall6 hr
Jun 20, 3:14 AM CDTAreal Flood WarningHUNDeKalb, Marshall6 hr
Jun 20, 8:59 AM CDTAreal Flood WarningHUNDeKalb, Marshall3 hr

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.