Alert archive / Alabama / Flash Flood Warnings in 2021

Flash Flood Warning 2, NWS Huntsville, AL

March 17, 2021Cullman County, Morgan County, Alabama

NWS Huntsville, AL issued this flash flood warning at Mar 17, 2021, 4:44 PM CDT for Cullman County, Morgan County, Alabama. It was in force for 5 hr. 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: Mar 17, 2021, 4:44 PM CDT (21:44 UTC)
Expired: Mar 17, 2021, 10:09 PM CDT
In force: 5 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), 84 km from the middle of the area, began a volume at 21:48 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
Mar 17, 8:00 PM CDT	FLASH FLOOD	5 S Falkville, AL	RESCUE SQUAD RESPONDING TO A SWIFT WATER RESCUE ON WILHITE ROAD IN LACON.
Mar 17, 10:03 PM CDT	FLASH FLOOD	8 Wsw Owens Crossroads, AL	RESIDENCE IN LACEYS SPRING AT RIVER LOOP ROAD HAS STANDING WATER IN THE HOME.

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

The nearest sounding before it

Birmingham, AL (KBMX), launched 12:00Z, 9.7 hours before the alert went out and 140 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: 658 J/kg
Mixed-layer CIN: -112 J/kg
Mixed-layer LCL: 759 m above ground
0-6 km bulk shear: 59 kt
0-1 km storm-relative helicity: 169 m²/s²
0-3 km storm-relative helicity: 301 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 2.1

Open this sounding in Storm Lab

The text

As transmitted.

757 
WGUS54 KHUN 172144
FFWHUN
ALC043-103-180130-
/O.NEW.KHUN.FF.W.0002.210317T2144Z-210318T0130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Huntsville AL
444 PM CDT Wed Mar 17 2021

The National Weather Service in Huntsville has issued a

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

* Until 830 PM CDT.

* At 444 PM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 1 and 3 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...
  Hartselle, Redstone Arsenal, Falkville, Baldwin, Vinemont, 
  Somerville, West Point, Eva, Lacon, Cole Springs, Battleground, 
  Jones Chapel, Florette, Logan, Valhermoso Springs, Crane Hill and 
  Laceys Spring.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Excessive runoff from heavy rainfall will cause flooding of small 
creeks and streams, country roads, farmland, and other low lying 
spots.

&&

LAT...LON 3431 8711 3454 8667 3454 8664 3458 8661
      3458 8659 3456 8655 3451 8656 3400 8711

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...2-4 INCHES IN 4 HOURS 

$$

KDW

2 follow-up statements

978 
WGUS54 KHUN 180006
FFWHUN
ALC043-103-180330-
/O.EXT.KHUN.FF.W.0002.000000T0000Z-210318T0330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Huntsville AL
706 PM CDT Wed Mar 17 2021

The National Weather Service in Huntsville has extended the

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

* Until 1030 PM CDT.

* At 706 PM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 2 and 4 inches of rain 
  have fallen. Flash flooding is already occurring and has been 
  reported in parts of the area, including portions of NW Cullman 
  County, particularly in areas from Crane Hill to West Point. Also, 
  flooding has been reported in eastern Morgan County along and near 
  Highway 36 south of Somerville.

  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...
  Hartselle, Redstone Arsenal, Falkville, Baldwin, Vinemont, 
  Somerville, West Point, Eva, Lacon, Cole Springs, Battleground, 
  Jones Chapel, Florette, Logan, Valhermoso Springs, Crane Hill and 
  Laceys Spring.

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 8711 3454 8667 3454 8664 3458 8661
      3458 8659 3456 8655 3451 8656 3400 8711

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...1-3 INCHES IN 4 HOURS 

$$

KDW

407 
WGUS74 KHUN 180309
FFSHUN

Flash Flood Statement
National Weather Service Huntsville AL
1009 PM CDT Wed Mar 17 2021

ALC043-103-180319-
/O.CAN.KHUN.FF.W.0002.000000T0000Z-210318T0330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Cullman AL-Morgan AL-
1009 PM CDT Wed Mar 17 2021

...FLASH FLOOD WARNING FOR NORTHWESTERN CULLMAN AND SOUTHERN MORGAN 
COUNTIES HAS BEEN REPLACED WITH A FLOOD WARNING...

LAT...LON 3431 8711 3454 8667 3454 8664 3458 8661
      3458 8659 3456 8655 3451 8656 3400 8711

$$

KTW

The office that day

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

Issued	Product	Office	Counties	Lasted
Mar 17, 1:24 AM CDT	Dense Fog Advisory	HUN	Cullman, DeKalb, Jackson, Marshall	7 hr
Mar 17, 7:25 AM CDT	Special Weather Statement	HUN	Morgan	50 min
Mar 17, 7:57 AM CDT	Special Weather Statement	HUN	Madison	48 min
Mar 17, 7:59 AM CDT	Special Weather Statement	HUN	Colbert	46 min
Mar 17, 9:52 AM CDT	Special Weather Statement	HUN	Jackson	23 min
Mar 17, 3:40 PM CDT	Tornado Warning	HUN	Colbert, Franklin	35 min
Mar 17, 4:07 PM CDT	Severe Thunderstorm Warning	HUN	Colbert, Franklin, Lauderdale	26 min
Mar 17, 4:17 PM CDT	Flash Flood Watch	HUN	Colbert, Cullman, DeKalb, Franklin, Jackson, Lauderdale and 5 more	8 hr
Mar 17, 5:24 PM CDT	Areal Flood Warning	HUN	Colbert, Franklin, Lauderdale	9 hr
Mar 17, 5:49 PM CDT	Areal Flood Warning	HUN	Cullman	8 hr
Mar 17, 6:05 PM CDT	Severe Thunderstorm Warning	HUN	Marshall	22 min
Mar 17, 6:44 PM CDT	Tornado Warning	HUN	Cullman	31 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.