Alert archive / Alabama / Flash Flood Warnings in 1999

Flash Flood Warning 10, NWS Birmingham, AL

April 24, 1999Calhoun County, Alabama

NWS Birmingham, AL issued this flash flood warning at Apr 24, 1999, 5:55 PM CDT for Calhoun County, Alabama. It was in force for 2 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Apr 24, 1999, 5:55 PM CDT (22:55 UTC)
Expired: Apr 24, 1999, 7:55 PM CDT
In force: 2 hr
Issued by: NWS Birmingham, AL
Area: Whole counties

County Calhoun County, AL

The radar

The Birmingham radar (KBMX), 110 km from the middle of the area, began a volume at 22:57 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, 10.9 hours before the alert went out and 110 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 2163 J/kg
Mixed-layer CIN: -42 J/kg
Mixed-layer LCL: 634 m above ground
0-6 km bulk shear: 23 kt
0-1 km storm-relative helicity: 60 m²/s²
0-3 km storm-relative helicity: 74 m²/s²
Significant tornado parameter: 0.5
Supercell composite: 2.9

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
TTAA00 KBHM 242256
FFWBHM
ALC015-250055-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE BIRMINGHAM AL
555 PM CDT SAT APR 24 1999

THE NATIONAL WEATHER SERVICE IN BIRMINGHAM HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  CALHOUN COUNTY... IN EAST CENTRAL ALABAMA

* UNTIL 755 PM CDT

* AT 550 PM...RADAR INDICATED A BAND OF STRONG THUNDERSTORMS WITH VERY
  HEAVY RAINFALL EXTENDING FROM SOUTHERN ETOWAH COUNTY...SOUTHEASTWARD
  THROUGH MOST OF CALHOUN COUNTY...INTO CLEBURNE COUNTY.  RADAR HAS
  ESTIMATED THAT OVER TWO INCHES OF RAIN HAS FALLEN OVER MUCH OF
  CALHOUN COUNTY DURING THE PAST ONE TO TWO HOURS.  LAW ENFORCEMENT
  OFFICIALS IN CALHOUN COUNTY HAVE REPORTED FLOODING OF SEVERAL ROADS
  IN THE WEAVER AREA DURING THE PAST 30 MINUTES.

  AN ADDITIONAL ONE HALF TO ONE INCH OF RAIN MAY OCCUR OVER PARTS OF
  CALHOUN COUNTY THROUGH 645 PM...AGGRAVATING THE FLASH FLOODING
  THREAT.

DON'T DRIVE INTO AREAS WHERE WATER COVERS THE ROAD!

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 24, 2:04 PM CDT	Severe Thunderstorm Warning	BMX	Pickens	51 min
Apr 24, 2:31 PM CDT	Severe Thunderstorm Warning	BMX	Calhoun	49 min
Apr 24, 2:51 PM CDT	Severe Thunderstorm Warning	BMX	Pickens	49 min
Apr 24, 3:12 PM CDT	Severe Thunderstorm Warning	BMX	Cleburne	48 min
Apr 24, 3:19 PM CDT	Severe Thunderstorm Warning	BMX	Calhoun	36 min
Apr 24, 4:26 PM CDT	Severe Thunderstorm Warning	BMX	Marengo	49 min
Apr 24, 4:39 PM CDT	Severe Thunderstorm Warning	BMX	St. Clair	36 min
Apr 24, 4:57 PM CDT	Severe Thunderstorm Warning	BMX	Calhoun	48 min
Apr 24, 5:15 PM CDT	Severe Thunderstorm Warning	BMX	Marengo	35 min

Nearby

Flash Flood Warnings in Alabama, 1999 Every flash flood warning in 1999

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.