Alert archive / Alabama / Flash Flood Warnings in 2021

Flash Flood Warning 39, NWS Huntsville, AL

September 19, 2021Jackson County, Alabama

NWS Huntsville, AL issued this flash flood warning at Sep 19, 2021, 4:21 AM CDT for Jackson County, Alabama. It was in force for 3 hr. 1 report 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
Sep 19, 2021, 4:21 AM CDT (09:21 UTC)
Expired
Sep 19, 2021, 7:30 AM CDT
In force
3 hr
Issued by
NWS Huntsville, AL
Area
Storm-based polygon
Flood severity
None

County Jackson County, AL

The radar

The Northeast Alabama radar (KHTX), 25 km from the middle of the area, began a volume at 09:20 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

TimeReportWhereRemark
Sep 19, 7:29 AM CDTFLASH FLOOD4 Ene Gurley, ALWATER OVER HWY 65 NEAR GARTH. TIME ESTIMATED BASED ON HIGH RAIN RATES ON RADAR.

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

The nearest sounding before it

Nashville Metro, TN (KBNA), launched 00:00Z, 9.4 hours before the alert went out and 157 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, Nashville Metro, TN at 00:00Z on 2021-09-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 8 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Nashville Metro, TN at 00:00Z on 2021-09-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -57 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
8 J/kg
Mixed-layer CIN
-160 J/kg
Mixed-layer LCL
831 m above ground
0-6 km bulk shear
13 kt
0-1 km storm-relative helicity
-57 m²/s²
0-3 km storm-relative helicity
-71 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

568 
WGUS54 KHUN 190921
FFWHUN
ALC071-191230-
/O.NEW.KHUN.FF.W.0039.210919T0921Z-210919T1230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

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

The National Weather Service in Huntsville has issued a

* Flash Flood Warning for...
  Western Jackson County in northeastern Alabama...

* Until 730 AM CDT.

* At 421 AM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 0.5 and 1 inch of rain 
  has fallen in the last 30 minutes. 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 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...
  Scottsboro, Hollywood, Powell, Skyline, Gurley, Section, 
  Woodville, Pleasant Groves, Hytop, Dutton, Langston, Paint Rock, 
  Larkinsville, Lim Rock, Trenton, Hollytree, Princeton, Estillfork, 
  Garth and Larkin.

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 3453 8615 3453 8614 3455 8615 3460 8615
      3460 8633 3463 8636 3474 8636 3476 8634
      3480 8635 3483 8633 3487 8635 3491 8631
      3494 8633 3495 8629 3494 8629 3493 8626
      3499 8631 3499 8602 3455 8590 3452 8615

FLASH FLOOD...RADAR INDICATED

$$

AMP
1 follow-up statement
102 
WGUS74 KHUN 191044
FFSHUN

Flash Flood Statement
National Weather Service Huntsville AL
544 AM CDT Sun Sep 19 2021

ALC071-191230-
/O.CON.KHUN.FF.W.0039.000000T0000Z-210919T1230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Jackson AL-
544 AM CDT Sun Sep 19 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 730 AM CDT THIS 
MORNING FOR WESTERN JACKSON COUNTY...

At 544 AM CDT, Doppler radar indicated thunderstorms producing heavy 
rain across the warned area. Between 1 and 2 inches of rain have 
fallen over the last hour and a half. Additional rainfall amounts of 
0.5 to 1 inch are possible in the warned area. 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...
Scottsboro, Hollywood, Powell, Skyline, Gurley, Section, Woodville, 
Pleasant Groves, Hytop, Dutton, Langston, Paint Rock, Larkinsville, 
Lim Rock, Trenton, Hollytree, Princeton, Estillfork, Garth and 
Larkin.

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 3453 8615 3453 8614 3455 8615 3460 8615
      3460 8633 3463 8636 3474 8636 3476 8634
      3480 8635 3483 8633 3487 8635 3491 8631
      3494 8633 3495 8629 3494 8629 3493 8626
      3499 8631 3499 8602 3455 8590 3452 8615

FLASH FLOOD...RADAR INDICATED

$$

AMP

The office that day

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

IssuedProductOfficeCountiesLasted
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, 1:13 PM CDTFlash Flood WarningHUNMadison, Marshall, 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.