Alert archive / Alabama / Flash Flood Warnings in 2012

Flash Flood Warning 21, NWS Mobile, AL

June 11, 2012Baldwin County, Alabama

NWS Mobile, AL issued this flash flood warning at Jun 11, 2012, 8:55 AM CDT for Baldwin 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
Jun 11, 2012, 8:55 AM CDT (13:55 UTC)
Expired
Jun 11, 2012, 2:45 PM CDT
In force
6 hr
Issued by
NWS Mobile, AL
Area
Storm-based polygon
Flood severity
None

County Baldwin County, AL

The radar

The Mobile radar (KMOB), 50 km from the middle of the area, began a volume at 13:55 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 12:00Z, 1.9 hours before the alert went out and 197 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 12:00Z on 2012-06-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3562 joules per kilogram.LCLEL10008507005003002001001 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, Slidell Radar S, LA at 12:00Z on 2012-06-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 23 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
3562 J/kg
Mixed-layer CIN
-1 J/kg
Mixed-layer LCL
443 m above ground
0-6 km bulk shear
17 kt
0-1 km storm-relative helicity
23 m²/s²
0-3 km storm-relative helicity
117 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.

449 
WGUS54 KMOB 111355
FFWMOB
ALC003-111945-
/O.NEW.KMOB.FF.W.0021.120611T1355Z-120611T1945Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE MOBILE AL
855 AM CDT MON JUN 11 2012

THE NATIONAL WEATHER SERVICE IN MOBILE HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  CENTRAL BALDWIN COUNTY IN SOUTHWEST ALABAMA...

* UNTIL 245 PM CDT

* AT 845 AM CDT...EMERGENCY MANAGEMENT OFFICIALS REPORTED FLASH
  FLOODING OVER THE WARNED AREA AND RADAR ESTIMATES SHOW 2 TO 3
  INCHES OF RAINFALL HAS OCCURRED OVER THE PAST HOUR...AND UP TO 7
  INCHES SINCE 5 AM. THIS IS CAUSING EXTREMELY DANGEROUS FLASH
  FLOODING IN THE WARNED AREA.

* FLASH FLOODING IS ESPECIALLY BAD IN THE BAY MINETTE AREA
  DOWNSTREAM OF THE VERY HEAVY RAIN. THE BALDWIN COUNTY EMERGENCY
  MANAGER HAS REPORTED THAT HOME EVACUATIONS HAVE BEGUN NEAR HIGHWAY
  31 AND HURRICANE ROAD.

* LOCATIONS IMPACTED INCLUDE...
  STAPLETON...          I65 AND AL 59...      I65 AND AL 225...
  BAY MINETTE...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS IS A VERY DANGEROUS AND LIFE THREATENING FLOODING SITUATION. YOU
SHOULD NOT ATTEMPT TO TRAVEL. STAY HOME UNLESS YOU ARE FORCED TO
EVACUATE TO HIGHER GROUND.

A FLASH FLOOD WARNING MEANS FLOODING IS IMMINENT OR OCCURRING. SEEK
HIGHER GROUND IMMEDIATELY. DO NOT DRIVE OR WALK INTO AREAS WHERE
WATER CROSSES A ROAD. TURN AROUND - DON'T DROWN!

&&

LAT...LON 3079 8793 3095 8789 3095 8788 3095 8787
      3096 8762 3087 8763 3084 8762 3078 8756
      3071 8770

$$

PURDY

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 10, 8:47 PM CDTRiver Flood WarningMOBMobile30 hr
Jun 11, 5:47 AM CDTAreal Flood AdvisoryMOBBaldwin118 min
Jun 11, 6:43 AM CDTAreal Flood AdvisoryMOBBaldwin, Mobile2 hr
Jun 11, 3:28 PM CDTSevere Thunderstorm WarningMOBConecuh, Escambia, Monroe62 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.