Alert archive / Alabama / Flash Flood Warnings in 2021

Flash Flood Warning 13, NWS Huntsville, AL

March 28, 2021Lauderdale County, Alabama

NWS Huntsville, AL issued this flash flood warning at Mar 28, 2021, 1:52 AM CDT for Lauderdale 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: Mar 28, 2021, 1:52 AM CDT (06:52 UTC)
Expired: Mar 28, 2021, 5:00 AM CDT
In force: 3 hr
Issued by: NWS Huntsville, AL
Area: Storm-based polygon
Flood severity: None

County Lauderdale County, AL

The radar

The Columbus AFB radar (KGWX), 120 km from the middle of the area, began a volume at 06:51 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

Little Rock, AR (KLZK), launched 00:00Z, 6.9 hours before the alert went out and 178 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: 894 J/kg
Mixed-layer CIN: -17 J/kg
Mixed-layer LCL: 1261 m above ground
0-6 km bulk shear: 79 kt
0-1 km storm-relative helicity: 64 m²/s²
0-3 km storm-relative helicity: 209 m²/s²
Significant tornado parameter: 0.7
Supercell composite: 8.7

Open this sounding in Storm Lab

The text

As transmitted.

774 
WGUS54 KHUN 280652
FFWHUN
ALC077-281000-
/O.NEW.KHUN.FF.W.0013.210328T0652Z-210328T1000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Huntsville AL
152 AM CDT Sun Mar 28 2021

The National Weather Service in Huntsville has issued a

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

* Until 500 AM CDT.

* At 152 AM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 1 and 2 inches of rain 
  have fallen. Flash flooding is ongoing or expected to begin 
  shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Doppler radar.

  IMPACT...Flooding of small creeks and streams, urban areas,
           highways, streets and underpasses as well as other
           drainage and low lying areas.

* Some locations that will experience flash flooding include...
  Waterloo, Wright and Threet.

Additional rainfall amounts of 1 to 2 inches are possible in the 
warned area.

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 3500 8761 3488 8797 3490 8804 3489 8810
      3490 8814 3493 8816 3499 8820 3501 8820

FLASH FLOOD...RADAR INDICATED

$$

GH

1 follow-up statement

206 
WGUS74 KHUN 280951
FFSHUN

Flash Flood Statement
National Weather Service Huntsville AL
451 AM CDT Sun Mar 28 2021

ALC077-281001-
/O.EXP.KHUN.FF.W.0013.000000T0000Z-210328T1000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Lauderdale AL-
451 AM CDT Sun Mar 28 2021

...FLASH FLOOD WARNING WILL EXPIRE AT 5 AM CDT EARLY THIS MORNING 
FOR NORTHWESTERN LAUDERDALE COUNTY...

The heavy rain has ended. Flooding is no longer expected to pose a 
threat. Please continue to heed remaining road closures.

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

LAT...LON 3500 8761 3488 8797 3490 8804 3489 8810
      3490 8814 3493 8816 3499 8820 3501 8820

$$

GH

The office that day

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

Issued	Product	Office	Counties	Lasted
Mar 28, 12:31 AM CDT	Severe Thunderstorm Warning	HUN	Colbert, Lauderdale	44 min
Mar 28, 1:13 AM CDT	Special Weather Statement	HUN	Lauderdale	47 min
Mar 28, 2:39 AM CDT	Special Weather Statement	HUN	Colbert	51 min
Mar 28, 2:45 AM CDT	Special Weather Statement	HUN	Franklin	45 min
Mar 28, 3:09 AM CDT	Severe Thunderstorm Warning	HUN	Colbert, Franklin, Lawrence	36 min
Mar 28, 3:34 AM CDT	Severe Thunderstorm Warning	HUN	Lawrence, Limestone, Morgan	26 min
Mar 28, 3:58 AM CDT	Severe Thunderstorm Warning	HUN	Jackson, Limestone, Madison, Morgan	47 min
Mar 28, 4:26 AM CDT	Severe Thunderstorm Warning	HUN	Jackson	34 min
Mar 28, 4:46 AM CDT	Severe Thunderstorm Warning	HUN	Jackson, Limestone, Madison, Morgan	44 min
Mar 28, 5:02 AM CDT	Severe Thunderstorm Warning	HUN	Cullman	28 min
Mar 28, 5:21 AM CDT	Severe Thunderstorm Warning	HUN	Jackson	24 min
Mar 28, 5:30 AM CDT	Severe Thunderstorm Warning	HUN	Cullman	30 min
Mar 28, 5:41 AM CDT	Areal Flood Warning	HUN	Madison	3 hr
Mar 28, 5:57 AM CDT	Severe Thunderstorm Warning	HUN	DeKalb, Marshall	33 min
Mar 28, 6:26 AM CDT	Special Weather Statement	HUN	DeKalb	34 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.