Alert archive / Alabama / Flash Flood Warnings in 2012

Flash Flood Warning 18, NWS Birmingham, AL

July 27, 2012Blount County, Alabama

NWS Birmingham, AL issued this flash flood warning at Jul 27, 2012, 4:48 PM CDT for Blount County, Alabama. It was in force for 2 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: Jul 27, 2012, 4:48 PM CDT (21:48 UTC)
Expired: Jul 27, 2012, 6:54 PM CDT
In force: 2 hr
Issued by: NWS Birmingham, AL
Area: Storm-based polygon
Flood severity: None

County Blount County, AL

The radar

The Birmingham radar (KBMX), 92 km from the middle of the area, began a volume at 21:50 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

Time	Report	Where	Remark
Jul 27, 5:18 PM CDT	FLASH FLOOD	Oneonta, AL	SEVERAL ROADWAYS FLOODED WITHIN THE CITY OF ONEONTA...AND AT LEAST ONE BUSINESS WAS FLOODED DUE TO THE PERSISTENT HEAVY RAINFALL.

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

The nearest sounding before it

Birmingham, AL (KBMX), launched 12:00Z, 9.8 hours before the alert went out and 92 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: 1540 J/kg
Mixed-layer CIN: -34 J/kg
Mixed-layer LCL: 840 m above ground
0-6 km bulk shear: 14 kt
0-1 km storm-relative helicity: 45 m²/s²
0-3 km storm-relative helicity: 9 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.

266 
WGUS54 KBMX 272148
FFWBMX
ALC009-280100-
/O.NEW.KBMX.FF.W.0018.120727T2148Z-120728T0100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE BIRMINGHAM AL
448 PM CDT FRI JUL 27 2012

THE NATIONAL WEATHER SERVICE IN BIRMINGHAM HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  EASTERN BLOUNT COUNTY IN ALABAMA...

* UNTIL 800 PM CDT

* AT 447 PM CDT...THE PUBLIC REPORTED FLASH FLOODING WITHIN THE CITY 
OF ONEONTA WITH RAINFALL ESTIMATES OF 4-5 INCHES BASED ON RADAR.

* RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH FLOODING TO
  OCCUR. SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
  BLOUNTSVILLE...CLEVELAND...ONEONTA...ALLGOOD...DALLAS...FAIRVIEW...
  LOCUST FORK...NECTAR...ROSA AND SUSAN MOORE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS IS A DANGEROUS SITUATION. RAINFALL FROM PERSISTENT RAINBANDS
WILL PRODUCE FLOODING IN LOW LYING AREAS AND ALONG STREETS. MANY
ROADS WILL BE CLOSED DUE TO HIGH WATER AND DRIVING IS NOT RECOMMENDED
DURING THE NEXT SEVERAL HOURS.

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.

&&

TO REPORT SEVERE WEATHER...
CALL 1-800-856-0758 OR TWEET YOUR REPORT USING HASHTAG ALWX

LAT...LON 3411 8637 3408 8632 3405 8633 3398 8633
      3394 8637 3394 8634 3382 8643 3382 8647
      3380 8652 3380 8656 3387 8671 3401 8667
      3412 8655

$$

56

2 follow-up statements

797 
WGUS74 KBMX 272254
FFSBMX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE BIRMINGHAM AL
554 PM CDT FRI JUL 27 2012

ALC009-280100-
/O.CON.KBMX.FF.W.0018.000000T0000Z-120728T0100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BLOUNT AL-
554 PM CDT FRI JUL 27 2012

...FLASH FLOOD WARNING REMAINS IN EFFECT FOR EASTERN BLOUNT COUNTY
UNTIL 800 PM CDT...

AT 545 PM CDT...ONGOING FLASH FLOODING CONTINUES TO BE POSSIBLE 
ACROSS EASTERN BLOUNT COUNTY...INCLUDING THE CITY OF ONEONTA. 
REPORTS OF ONGOING FLASH FLOODING BY THE PUBLIC AND EMERGENCY 
MANAGMENT HAVE OCCURRED OVER THE PAST HOUR...AND CONTINUED FLASH 
FLOODING STILL COULD BE POSSIBLE OVER THE WARNED AREA.

SOME LOCATIONS THAT COULD STILL EXPERIENCE FLASH FLOODING 
INCLUDE...CLEVELAND...ONEONTA...ALLGOOD...FAIRVIEW...LOCUST 
FORK...NECTAR...ROSA AND SUSAN MOORE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS IS A DANGEROUS SITUATION. RAINFALL FROM PERSISTENT THUNDERSTORMS
WILL PRODUCE FLOODING IN LOW LYING AREAS AND ALONG STREETS. MANY 
ROADS COULD BE CLOSED DUE TO HIGH WATER AND DRIVING IS NOT 
RECOMMENDED DURING THE NEXT SEVERAL HOURS.

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

&&

LAT...LON 3411 8637 3408 8632 3405 8633 3398 8633
      3394 8637 3394 8634 3382 8643 3382 8647
      3380 8652 3380 8656 3387 8671 3401 8667
      3412 8655

$$

56

547 
WGUS74 KBMX 272354
FFSBMX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE BIRMINGHAM AL
654 PM CDT FRI JUL 27 2012

ALC009-280009-
/O.CAN.KBMX.FF.W.0018.000000T0000Z-120728T0100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BLOUNT AL-
654 PM CDT FRI JUL 27 2012

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

EXCESS RUNOFF FROM HEAVY RAIN HAS ENDED OVER THE WARNED AREA. STREAMS
AND CREEKS IN THE WARNED AREA HAVE RECEDED OR WERE BEGINNING TO
RECEDE...ENDING THE FLOOD THREAT. IF FLOODING HAS BEEN OBSERVED...
PLEASE REPORT IT TO YOUR LOCAL LAW ENFORCEMENT AGENCY.

LAT...LON 3411 8637 3408 8632 3405 8633 3398 8633
      3394 8637 3394 8634 3382 8643 3382 8647
      3380 8652 3380 8656 3387 8671 3401 8667
      3412 8655

$$

56

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 26, 7:45 PM CDT	Special Weather Statement	BMX	Russell	30 min
Jul 27, 1:46 PM CDT	Special Weather Statement	BMX	Jefferson	44 min
Jul 27, 2:41 PM CDT	Special Weather Statement	BMX	Etowah	34 min
Jul 27, 3:09 PM CDT	Special Weather Statement	BMX	Shelby	36 min
Jul 27, 3:28 PM CDT	Special Weather Statement	BMX	Bibb	32 min
Jul 27, 3:34 PM CDT	Special Weather Statement	BMX	Greene	26 min
Jul 27, 3:37 PM CDT	Special Weather Statement	BMX	Blount	23 min
Jul 27, 3:48 PM CDT	Special Weather Statement	BMX	Shelby	27 min
Jul 27, 3:55 PM CDT	Special Weather Statement	BMX	Sumter	35 min
Jul 27, 4:02 PM CDT	Areal Flood Advisory	BMX	Blount	58 min
Jul 27, 4:08 PM CDT	Special Weather Statement	BMX	Calhoun	37 min
Jul 27, 4:28 PM CDT	Severe Thunderstorm Warning	BMX	Blount	32 min
Jul 27, 4:32 PM CDT	Special Weather Statement	BMX	Marion	28 min
Jul 27, 4:58 PM CDT	Areal Flood Advisory	BMX	St. Clair	2 hr
Jul 27, 5:01 PM CDT	Special Weather Statement	BMX	St. Clair	29 min
Jul 27, 5:02 PM CDT	Areal Flood Advisory	BMX	Cherokee	118 min
Jul 27, 5:05 PM CDT	Special Weather Statement	BMX	Marion	40 min
Jul 27, 5:08 PM CDT	Special Weather Statement	BMX	Macon	37 min
Jul 27, 5:19 PM CDT	Areal Flood Advisory	BMX	Marion	116 min
Jul 27, 5:19 PM CDT	Special Weather Statement	BMX	Greene	26 min
Jul 27, 6:25 PM CDT	Special Weather Statement	BMX	Russell	35 min
Jul 27, 6:45 PM CDT	Special Weather Statement	BMX	Lamar	45 min
Jul 27, 6:57 PM CDT	Special Weather Statement	BMX	Russell	33 min

Nearby

Flash Flood Warnings in Alabama, 2012 Every 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.