Alert archive / Alabama / Flash Flood Warnings in 2012

Flash Flood Warning 29, NWS Mobile, AL

August 30, 2012Mobile County, Washington County, Alabama

NWS Mobile, AL issued this flash flood warning at Aug 30, 2012, 12:22 AM CDT for Mobile County, Washington County, Alabama. It was in force for 6 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 30, 2012, 12:22 AM CDT (05:22 UTC)
Expired
Aug 30, 2012, 6:15 AM CDT
In force
6 hr
Issued by
NWS Mobile, AL
Area
Storm-based polygon
Flood severity
None

Counties Mobile County, AL, Washington County, AL

The radar

The Mobile radar (KMOB), 17 km from the middle of the area, began a volume at 05:24 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

Slidell Radar S, LA (KSIL), launched 00:00Z, 5.4 hours before the alert went out and 141 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, Slidell Radar S, LA at 00:00Z on 2012-08-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 408 joules per kilogram.LCLEL10008507005003002001001 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, Slidell Radar S, LA at 00:00Z on 2012-08-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 299 square meters per square second.19395878Sfc1 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
408 J/kg
Mixed-layer CIN
0 J/kg
Mixed-layer LCL
464 m above ground
0-6 km bulk shear
55 kt
0-1 km storm-relative helicity
299 m²/s²
0-3 km storm-relative helicity
301 m²/s²
Significant tornado parameter
0.8
Supercell composite
6.3

Open this sounding in Storm Lab

The text

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

989 
WGUS54 KMOB 300522
FFWMOB
ALC097-129-301115-
/O.NEW.KMOB.FF.W.0029.120830T0522Z-120830T1115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE MOBILE AL
1222 AM CDT THU AUG 30 2012

THE NATIONAL WEATHER SERVICE IN MOBILE HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  WESTERN MOBILE COUNTY IN SOUTHWEST ALABAMA...
  SOUTHWESTERN WASHINGTON COUNTY IN SOUTHWEST ALABAMA...

* UNTIL 615 AM CDT

* AT 1215 AM CDT...VERY HEAVY RAINFALL WAS INDICATED OVER THE        
  WARNED AREA AND RADAR ESTIMATES SHOW RAINFALL RATES OF 1.5 TO
  TO 2.5 INCHES PER HOUR. THIS WILL LIKELY CAUSE FLASH FLOODING IN
  THE WARNED AREA GIVEN WET SOILS FROM THE RAIN THAT HAS ALREADY
  FALLEN. ALSO THUNDERSTORMS WILL CONTINUE MOVING REPEATEDLY OVER
  THE SAME AREA AS ISAAC'S BANDS HAVE BECOME NEAR STATIONARY OVER    
  THE SAME AREAS.

* LOCATIONS IMPACTED INCLUDE...
  REGIONAL AIRPORT IN WEST MOBILE...          CODEN...
  TILLMANS CORNER...    THEODORE...           SEMMES...
  GULFCREST...          GRAND BAY...          CITRONELLE...
  CHUNCHULA...

LAT...LON 3037 8826 3038 8829 3036 8832 3039 8833
      3037 8838 3039 8840 3139 8845 3126 8824
      3103 8813 3036 8817 3034 8818 3033 8820
      3036 8820 3037 8825 3032 8825

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 29, 7:27 PM CDTTornado WarningMOBMonroe, Wilcox30 min
Aug 29, 7:29 PM CDTSmall Craft AdvisoryMOB33 hr
Aug 29, 7:45 PM CDTCoastal Flood WarningMOB21 hr
Aug 30, 12:52 AM CDTWind AdvisoryMOBWashington16 hr
Aug 30, 2:28 AM CDTAreal Flood WarningMOBMobile, Washington12 hr
Aug 30, 2:46 AM CDTTornado WarningMOBCovington33 min
Aug 30, 3:53 AM CDTTornado WarningMOBCovington, Escambia37 min
Aug 30, 4:09 AM CDTTornado WarningMOBButler, Crenshaw16 min
Aug 30, 4:31 AM CDTTornado WarningMOBWashington29 min
Aug 30, 4:32 AM CDTTornado WarningMOBCovington28 min
Aug 30, 6:43 AM CDTTornado WarningMOBChoctaw, Washington37 min
Aug 30, 7:41 AM CDTTornado WarningMOBMobile33 min
Aug 30, 8:10 AM CDTTornado WarningMOBChoctaw, Washington35 min
Aug 30, 8:13 AM CDTTornado WarningMOBWashington32 min
Aug 30, 8:45 AM CDTTornado WarningMOBChoctaw, Washington45 min
Aug 30, 9:01 AM CDTTornado WarningMOBMobile, Washington44 min
Aug 30, 10:16 AM CDTTornado WarningMOBChoctaw, Washington44 min
Aug 30, 10:56 AM CDTTornado WarningMOBChoctaw49 min
Aug 30, 11:32 AM CDTSevere Thunderstorm WarningMOBMobile43 min
Aug 30, 11:44 AM CDTFlash Flood WarningMOBMobile, Washington6 hr
Aug 30, 11:56 AM CDTTornado WarningMOBChoctaw33 min
Aug 30, 4:29 PM CDTHigh Surf AdvisoryMOB20 hr

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.