Alert archive / Alabama / Flash Flood Warnings in 2008

Flash Flood Warning 21, NWS Huntsville, AL

July 22, 2008Lawrence County, Morgan County, Alabama

NWS Huntsville, AL issued this flash flood warning at Jul 22, 2008, 2:38 PM CDT for Lawrence County, Morgan County, Alabama. It was in force for 69 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
Jul 22, 2008, 2:38 PM CDT (19:38 UTC)
Expired
Jul 22, 2008, 3:47 PM CDT
In force
69 min
Issued by
NWS Huntsville, AL
Area
Storm-based polygon
Flood severity
None

Counties Lawrence County, AL, Morgan County, AL

The radar

The Northeast Alabama radar (KHTX), 92 km from the middle of the area, began a volume at 19:38 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, 7.6 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 2008-07-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1950 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, Birmingham, AL at 12:00Z on 2008-07-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -44 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
1950 J/kg
Mixed-layer CIN
-93 J/kg
Mixed-layer LCL
1175 m above ground
0-6 km bulk shear
11 kt
0-1 km storm-relative helicity
-44 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.

000 
WGUS54 KHUN 221938
FFWHUN
ALC079-103-222130-
/O.NEW.KHUN.FF.W.0021.080722T1938Z-080722T2130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE HUNTSVILLE AL
238 PM CDT TUE JUL 22 2008

THE NATIONAL WEATHER SERVICE IN HUNTSVILLE HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  NORTHWESTERN MORGAN COUNTY IN NORTH CENTRAL ALABAMA...
  EAST CENTRAL LAWRENCE COUNTY IN NORTHWEST ALABAMA...

* UNTIL 430 PM CDT

* AT 236 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED   
  A TRAINING THUNDERSTORM WITH EXTREMELY HEAVY RAINFALL OVER THE     
  DECATUR AREA. THE THUNDERSTORMS WERE DRIFTING EAST AT 10 MPH.

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO DECATUR    
  AND TRINITY...AS WELL AS HIGHWAY 20.

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL
CREEKS AND STREAMS...URBAN AREAS...HIGHWAYS...STREETS AND UNDERPASSES
AS WELL AS OTHER DRAINAGE AREAS AND LOW LYING SPOTS.

LAT...LON 3463 8698 3462 8698 3462 8696 3459 8693
      3459 8691 3451 8695 3455 8723 3470 8716

$$

BCC
1 follow-up statement
000 
WGUS74 KHUN 222047
FFSHUN

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE HUNTSVILLE AL
347 PM CDT TUE JUL 22 2008

ALC079-103-222057-
/O.CAN.KHUN.FF.W.0021.000000T0000Z-080722T2130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
347 PM CDT TUE JUL 22 2008

...THE FLASH FLOOD WARNING HAS BEEN CANCELLED FOR EAST CENTRAL
LAWRENCE AND NORTHWESTERN MORGAN COUNTIES...

NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED THE RAINFALL WAS
ENDING ACROSS THE WARNED AREA...AND THE FLOOD THREAT WAS DIMINISHING.
SOME MINOR FLOODING MAY CONTINUE...BUT THE SERIOUS THREAT OF FLOODING
IS ENDING. THUS...THE FLASH FLOOD WARNING HAS BEEN CANCELED.

MINOR FLOODING OF LOW LYING AND FLOOD PRONE AREAS ARE POSSIBLE...DUE
TO RECENT RAINFALL RUNOFF OF THIS STORM. STANDING WATER ON AREA
HIGHWAYS MAY CAUSE HYDROPLANING...WITH A LOST OF VEHICLE CONTROL
POSSIBLE.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 700 PM CDT
TUESDAY EVENING FOR NORTHERN ALABAMA AND CENTRAL TENNESSEE.

LAT...LON 3463 8698 3462 8698 3462 8696 3459 8693
      3459 8691 3451 8695 3455 8723 3470 8716

$$

BCC

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 22, 1:29 PM CDTSevere Thunderstorm WarningHUNCullman31 min
Jul 22, 1:37 PM CDTSevere Thunderstorm WarningHUNMorgan38 min
Jul 22, 1:44 PM CDTSevere Thunderstorm WarningHUNMadison46 min
Jul 22, 2:11 PM CDTSevere Thunderstorm WarningHUNJackson49 min
Jul 22, 2:21 PM CDTSevere Thunderstorm WarningHUNMadison39 min
Jul 22, 2:30 PM CDTSevere Thunderstorm WarningHUNLawrence, Limestone, Morgan30 min
Jul 22, 2:41 PM CDTSevere Thunderstorm WarningHUNJackson, Marshall38 min
Jul 22, 2:51 PM CDTSevere Thunderstorm WarningHUNLauderdale, Limestone24 min
Jul 22, 2:51 PM CDTSevere Thunderstorm WarningHUNDeKalb24 min
Jul 22, 2:53 PM CDTSevere Thunderstorm WarningHUNLawrence, Morgan37 min
Jul 22, 3:13 PM CDTSevere Thunderstorm WarningHUNLimestone32 min
Jul 22, 3:16 PM CDTSevere Thunderstorm WarningHUNDeKalb, Jackson33 min
Jul 22, 3:22 PM CDTSevere Thunderstorm WarningHUNDeKalb32 min
Jul 22, 3:39 PM CDTSevere Thunderstorm WarningHUNLimestone, Madison39 min
Jul 22, 3:54 PM CDTSevere Thunderstorm WarningHUNFranklin, Lawrence18 min
Jul 22, 6:41 PM CDTSevere Thunderstorm WarningHUNLauderdale38 min

Nearby

Flash Flood Warnings in Alabama, 2008Every flash flood warning in 2008

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.