Alert archive / Alabama / Flash Flood Warnings in 2012

Flash Flood Warning 31, NWS Birmingham, AL

August 17, 2012Lamar County, Alabama

NWS Birmingham, AL issued this flash flood warning at Aug 17, 2012, 3:18 AM CDT for Lamar 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
Aug 17, 2012, 3:18 AM CDT (08:18 UTC)
Expired
Aug 17, 2012, 6:30 AM CDT
In force
3 hr
Issued by
NWS Birmingham, AL
Area
Storm-based polygon
Flood severity
None

County Lamar County, AL

The radar

The Columbus AFB radar (KGWX), 23 km from the middle of the area, began a volume at 08:21 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, 8.3 hours before the alert went out and 144 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 2012-08-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1257 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 00:00Z on 2012-08-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -11 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
1257 J/kg
Mixed-layer CIN
-32 J/kg
Mixed-layer LCL
1382 m above ground
0-6 km bulk shear
19 kt
0-1 km storm-relative helicity
-11 m²/s²
0-3 km storm-relative helicity
60 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.

566 
WGUS54 KBMX 170818
FFWBMX
ALC075-171130-
/O.NEW.KBMX.FF.W.0031.120817T0818Z-120817T1130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE BIRMINGHAM AL
318 AM CDT FRI AUG 17 2012

THE NATIONAL WEATHER SERVICE IN BIRMINGHAM HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  LAMAR COUNTY IN WEST CENTRAL ALABAMA...

* UNTIL 630 AM CDT

* AT 316 AM CDT...NATIONAL WEATHER SERVICE INDICATED SLOW MOVING   
THUNDERSTORMS WITH VERY HEAVY RAINFALL ACROSS THE WARNED AREA. ONE 
TO TWO INCHES OF RAIN ARE POSSIBLE THROUGH 630 AM. THE TYPICAL 
TROUBLE SPOTS ARE RIVER ROAD NEAR SULLIGENT...OAK ROAD NEAR 
DETROIT...HAWKINGS HOLLOW ROAD NEAR HENSON SPRINGS...AND HIGHWAY 17 
IN VERNON.

* RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH FLOODING TO
  OCCUR. SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
  MILLPORT...SULLIGENT...VERNON...BEAVERTON...BEDFORD...BLOOMING
  GROVE...CREWS...DETROIT...KENNEDY AND LAMAR COUNTY AIRPORT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE
ROADWAY. THE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO CROSS
SAFELY.

&&

TO REPORT SEVERE WEATHER...
CALL 1-800-856-0758.

LAT...LON 3405 8821 3405 8799 3402 8799 3402 8795
      3353 8794 3353 8828

$$

75

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 17, 1:59 AM CDTSpecial Weather StatementBMXCherokee46 min
Aug 17, 2:03 AM CDTSpecial Weather StatementBMXMarion42 min
Aug 17, 2:39 AM CDTSpecial Weather StatementBMXWinston51 min
Aug 17, 2:42 AM CDTSpecial Weather StatementBMXMarion48 min
Aug 17, 4:10 AM CDTSpecial Weather StatementBMXWalker50 min
Aug 17, 4:13 AM CDTSpecial Weather StatementBMXPickens32 min
Aug 17, 4:33 AM CDTSpecial Weather StatementBMXPickens42 min
Aug 17, 4:37 AM CDTSpecial Weather StatementBMXTuscaloosa38 min
Aug 17, 5:54 AM CDTSpecial Weather StatementBMXSumter51 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.