Alert archive / Alabama / Flash Flood Warnings in 2021

Flash Flood Warning 27, NWS Huntsville, AL

July 25, 2021Cullman County, Morgan County, Alabama

NWS Huntsville, AL issued this flash flood warning at Jul 25, 2021, 7:11 PM CDT for Cullman County, Morgan County, Alabama. It was in force for 3 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: Jul 25, 2021, 7:11 PM CDT (00:11 UTC)
Expired: Jul 25, 2021, 9:57 PM CDT
In force: 3 hr
Issued by: NWS Huntsville, AL
Area: Storm-based polygon
Flood severity: None

Counties Cullman County, AL, Morgan County, AL

The radar

The Northeast Alabama radar (KHTX), 112 km from the middle of the area, began a volume at 00:12 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.

The nearest sounding before it

Birmingham, AL (KBMX), launched 00:00Z, 0.2 hours before the alert went out and 126 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: 189 J/kg
Mixed-layer CIN: -78 J/kg
Mixed-layer LCL: 1385 m above ground
0-6 km bulk shear: 6 kt
0-1 km storm-relative helicity: -15 m²/s²
0-3 km storm-relative helicity: 15 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

783 
WGUS54 KHUN 260011
FFWHUN
ALC043-103-260315-
/O.NEW.KHUN.FF.W.0027.210726T0011Z-210726T0315Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Huntsville AL
711 PM CDT Sun Jul 25 2021

The National Weather Service in Huntsville has issued a

* Flash Flood Warning for...
  Northwestern Cullman County in north central Alabama...
  Southwestern Morgan County in north central Alabama...

* Until 1015 PM CDT.

* At 711 PM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across Southwestern Morgan and Northwestern Cullman 
  Counties. Two to three inches of rain has fallen within the past 
  hour to the West of Falkville, and additional rainfall amounts up 
  to 1 to 2 inches are possible through 1015 PM CDT. 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...
  Hartselle, Falkville, Vinemont, West Point, Eva, Battleground, 
  Lacon, Massey, Cole Springs and Jones Chapel.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

In hilly terrain there are hundreds of low water crossings which are 
potentially dangerous in heavy rain. Do not attempt to cross flooded 
roads. Find an alternate route.

&&

LAT...LON 3446 8711 3445 8694 3435 8676 3426 8676
      3420 8692 3420 8705 3421 8711 3422 8711
      3423 8711 3424 8711 3426 8711 3427 8711
      3428 8711 3429 8711

FLASH FLOOD...RADAR INDICATED

$$

12

1 follow-up statement

801 
WGUS74 KHUN 260257
FFSHUN

Flash Flood Statement
National Weather Service Huntsville AL
957 PM CDT Sun Jul 25 2021

ALC043-103-260307-
/O.CAN.KHUN.FF.W.0027.000000T0000Z-210726T0315Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Cullman AL-Morgan AL-
957 PM CDT Sun Jul 25 2021

...FLASH FLOOD WARNING IS CANCELLED FOR NORTHWESTERN CULLMAN AND 
SOUTHWESTERN MORGAN COUNTIES...

Flood waters have receded and the heavy rain has ended. Flooding is 
no longer expected to pose a threat. Please continue to heed 
remaining road closures.

LAT...LON 3446 8711 3445 8694 3435 8676 3426 8676
      3420 8692 3420 8705 3421 8711 3422 8711
      3423 8711 3424 8711 3426 8711 3427 8711
      3428 8711 3429 8711

$$

12

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 26, 1:28 PM CDT	Special Weather Statement	HUN	Colbert	32 min
Jul 26, 2:37 PM CDT	Special Weather Statement	HUN	Jackson	23 min
Jul 26, 3:12 PM CDT	Special Weather Statement	HUN	Jackson	33 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.