Alert archive / Alabama / Flash Flood Warnings in 2012

Flash Flood Warning 21, NWS Huntsville, AL

May 6, 2012Marshall County, Alabama

NWS Huntsville, AL issued this flash flood warning at May 6, 2012, 6:45 AM CDT for Marshall County, Alabama. It was in force for 84 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
May 6, 2012, 6:45 AM CDT (11:45 UTC)
Expired
May 6, 2012, 8:09 AM CDT
In force
84 min
Issued by
NWS Huntsville, AL
Area
Storm-based polygon
Flood severity
None

County Marshall County, AL

The radar

The Northeast Alabama radar (KHTX), 69 km from the middle of the area, began a volume at 11:48 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.

The nearest sounding before it

Birmingham, AL (KBMX), launched 00:00Z, 11.8 hours before the alert went out and 137 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 00:00Z on 2012-05-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1387 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 00:00Z on 2012-05-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 9 square meters per square second.1939Sfc1 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
1387 J/kg
Mixed-layer CIN
-71 J/kg
Mixed-layer LCL
1525 m above ground
0-6 km bulk shear
10 kt
0-1 km storm-relative helicity
9 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, in the capitals the NWS used until 2016.

907 
WGUS54 KHUN 061145
FFWHUN
ALC095-061430-
/O.NEW.KHUN.FF.W.0021.120506T1145Z-120506T1430Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE HUNTSVILLE AL
645 AM CDT SUN MAY 6 2012

THE NATIONAL WEATHER SERVICE IN HUNTSVILLE HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  MARSHALL COUNTY IN NORTHEAST ALABAMA...

* UNTIL 930 AM CDT

* AT 643 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED   
  SLOW MOVING THUNDERSTORMS WITH VERY HEAVY RAINFALL MOVING INTO     
  WESTERN MARSHALL COUNTY. MORE THAN TWO INCHES OF RAINFALL HAS      
  ALREADY OCCURRED ACROSS WESTERN MARSHALL COUNTY...WITH ANOTHER     
  ONE TO TWO INCHES OF RAINFALL EXPECTED OVER THE NEXT TWO HOURS.

* RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH FLOODING TO
  OCCUR. SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
  ALBERTVILLE...ARAB AND GUNTERSVILLE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

ADDITIONAL RAINFALL AMOUNTS OF ONE TO TWO INCHES ARE POSSIBLE ACROSS 
WESTERN MARSHALL COUNTY.

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL
CREEKS AND STREAMS...HIGHWAYS AND UNDERPASSES. ADDITIONALLY...
COUNTRY ROADS AND FARMLANDS ALONG THE BANKS OF CREEKS...STREAMS AND
OTHER LOW LYING AREAS ARE SUBJECT TO FLOODING.

&&

LAT...LON 3424 8640 3426 8646 3429 8646 3430 8648
      3431 8657 3452 8655 3449 8651 3447 8647
      3448 8642 3451 8639 3452 8638 3452 8635
      3428 8615 3421 8622

$$

CCC
1 follow-up statement
094 
WGUS74 KHUN 061309
FFSHUN

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE HUNTSVILLE AL
809 AM CDT SUN MAY 6 2012

ALC095-061323-
/O.CAN.KHUN.FF.W.0021.000000T0000Z-120506T1430Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
MARSHALL AL-
809 AM CDT SUN MAY 6 2012

...THE FLASH FLOOD WARNING THAT WAS IN EFFECT FOR MARSHALL COUNTY IS
CANCELLED...

HEAVY RAIN HAS DIMINISHED OVER THE WARNED AREA AND NO REPORTS OF 
FLASH FLOODING HAVE BEEN RECEIVED.

IF FLOODING HAS BEEN OBSERVED...PLEASE REPORT IT TO YOUR LOCAL LAW 
ENFORCEMENT AGENCY.

LAT...LON 3424 8640 3426 8646 3429 8646 3430 8648
      3431 8657 3452 8655 3449 8651 3447 8647
      3448 8642 3451 8639 3452 8638 3452 8635
      3428 8615 3421 8622

$$

KULA

The office that day

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

IssuedProductOfficeCountiesLasted
May 5, 7:16 PM CDTSpecial Weather StatementHUNMorgan29 min
May 6, 12:42 AM CDTSpecial Weather StatementHUNMadison33 min
May 6, 3:43 AM CDTSpecial Weather StatementHUNMarshall47 min
May 6, 4:03 AM CDTSpecial Weather StatementHUNMarshall42 min
May 6, 4:31 AM CDTSpecial Weather StatementHUNMarshall44 min
May 6, 4:59 AM CDTSpecial Weather StatementHUNMarshall46 min
May 6, 5:58 AM CDTSpecial Weather StatementHUNMarshall47 min
May 6, 6:01 AM CDTSpecial Weather StatementHUNMadison29 min
May 6, 6:07 AM CDTSpecial Weather StatementHUNMadison23 min
May 6, 6:20 AM CDTSpecial Weather StatementHUNMorgan25 min
May 6, 6:41 AM CDTSpecial Weather StatementHUNCullman49 min
May 6, 7:31 AM CDTSpecial Weather StatementHUNMorgan59 min
May 6, 3:25 PM CDTSpecial Weather StatementHUNDeKalb50 min
May 6, 4:05 PM CDTSpecial Weather StatementHUNDeKalb40 min
May 6, 4:12 PM CDTSpecial Weather StatementHUNJackson48 min
May 6, 4:40 PM CDTSpecial Weather StatementHUNLawrence50 min
May 6, 4:45 PM CDTSpecial Weather StatementHUNDeKalb45 min
May 6, 4:57 PM CDTSpecial Weather StatementHUNDeKalb48 min
May 6, 5:00 PM CDTSpecial Weather StatementHUNFranklin45 min
May 6, 5:20 PM CDTSpecial Weather StatementHUNJackson40 min
May 6, 5:31 PM CDTSpecial Weather StatementHUNDeKalb44 min
May 6, 5:41 PM CDTSpecial Weather StatementHUNFranklin49 min
May 6, 5:52 PM CDTSpecial Weather StatementHUNMarshall38 min
May 6, 6:08 PM CDTSevere Thunderstorm WarningHUNFranklin22 min
May 6, 6:25 PM CDTSevere Thunderstorm WarningHUNFranklin23 min
May 6, 6:29 PM CDTSpecial Weather StatementHUNMarshall46 min
May 6, 6:32 PM CDTSpecial Weather StatementHUNJackson28 min
May 6, 6:35 PM CDTSpecial Weather StatementHUNMarshall40 min

Nearby

Flash Flood Warnings in Alabama, 2012Every flash flood warning in 2012

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.