Alert archive / Alabama / Flash Flood Warnings in 2021

Flash Flood Warning 41, NWS Huntsville, AL

September 19, 2021Madison County, Marshall County, Morgan County, Alabama

NWS Huntsville, AL issued this flash flood warning at Sep 19, 2021, 1:13 PM CDT for Madison County, Marshall 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
Sep 19, 2021, 1:13 PM CDT (18:13 UTC)
Expired
Sep 19, 2021, 3:53 PM CDT
In force
3 hr
Issued by
NWS Huntsville, AL
Area
Storm-based polygon
Flood severity
None

Counties Madison County, AL, Marshall County, AL, Morgan County, AL

The radar

The Northeast Alabama radar (KHTX), 62 km from the middle of the area, began a volume at 18:16 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 12:00Z, 6.2 hours before the alert went out and 160 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, Birmingham, AL at 12:00Z on 2021-09-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 326 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, Birmingham, AL at 12:00Z on 2021-09-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 21 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
326 J/kg
Mixed-layer CIN
-14 J/kg
Mixed-layer LCL
537 m above ground
0-6 km bulk shear
8 kt
0-1 km storm-relative helicity
21 m²/s²
0-3 km storm-relative helicity
5 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

815 
WGUS54 KHUN 191813
FFWHUN
ALC089-095-103-192115-
/O.NEW.KHUN.FF.W.0041.210919T1813Z-210919T2115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Huntsville AL
113 PM CDT Sun Sep 19 2021

The National Weather Service in Huntsville has issued a

* Flash Flood Warning for...
  Central Madison County in north central Alabama...
  Southeastern Morgan County in north central Alabama...
  West Central Marshall County in northeastern Alabama...

* Until 415 PM CDT.

* At 113 PM CDT, local law enforcement reported heavy rain across 
  the warned area. Between 2 and 3 inches of rain have fallen. The 
  expected rainfall rate is 1 to 2 inches in 1 hour. 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 heavy rain.

  SOURCE...Law enforcement reported.

  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...
  Huntsville, Madison, Redstone Arsenal, Moores Mill, Meridianville, 
  Hazel Green, Owens Cross Roads, Triana, Marshall Space Flight 
  Center, University Of Alabama In Huntsville, Alabama A And M 
  University, Morgan City, Harvest, Union Grove, Farley, Whitesburg, 
  Laceys Spring, Hampton Cove, Ryland and Valhermoso Springs.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Be aware of your surroundings and do not drive on flooded roads.

&&

LAT...LON 3457 8674 3482 8673 3492 8673 3492 8645
      3437 8642 3437 8658 3437 8674

FLASH FLOOD...OBSERVED
EXPECTED RAINFALL...1-2 INCHES IN 1 HOUR

$$

GH
1 follow-up statement
844 
WGUS74 KHUN 192053
FFSHUN

Flash Flood Statement
National Weather Service Huntsville AL
353 PM CDT Sun Sep 19 2021

ALC089-095-103-192103-
/O.CAN.KHUN.FF.W.0041.000000T0000Z-210919T2115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Madison AL-Marshall AL-Morgan AL-
353 PM CDT Sun Sep 19 2021

...FLASH FLOOD WARNING IS CANCELLED FOR CENTRAL MADISON, 
SOUTHEASTERN MORGAN AND WEST CENTRAL MARSHALL COUNTIES...

A new flood warning will be replacing this across the area.

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

LAT...LON 3457 8674 3482 8673 3492 8673 3492 8645
      3437 8642 3437 8658 3437 8674

$$

GH

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 19, 4:21 AM CDTFlash Flood WarningHUNJackson3 hr
Sep 19, 7:25 AM CDTFlash Flood WarningHUNMadison, Marshall3 hr
Sep 19, 7:29 AM CDTAreal Flood WarningHUNJackson9 hr
Sep 19, 8:23 AM CDTRiver Flood WarningHUNJackson, Madison, Marshall4 days
Sep 19, 8:27 AM CDTRiver Flood WarningHUNMadison41 hr
Sep 19, 10:18 AM CDTAreal Flood WarningHUNMadison, Marshall6 hr
Sep 19, 10:59 AM CDTAreal Flood WarningHUNMadison, Morgan5 hr
Sep 19, 12:49 PM CDTAreal Flood WarningHUNLimestone, Morgan3 hr
Sep 19, 3:52 PM CDTAreal Flood WarningHUNJackson, Limestone, Madison, Marshall, Morgan6 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.