Alert archive / Alabama / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 54, NWS Mobile, AL

May 12, 2012Washington County, Alabama

NWS Mobile, AL issued this severe thunderstorm warning at May 12, 2012, 2:28 PM CDT for Washington County, Alabama. It was in force for 41 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
May 12, 2012, 2:28 PM CDT (19:28 UTC)
Expired
May 12, 2012, 3:09 PM CDT
In force
41 min
Issued by
NWS Mobile, AL
Area
Storm-based polygon

County Washington County, AL

The radar

The Mobile radar (KMOB), 72 km from the middle of the area, began a volume at 19:31 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, 7.5 hours before the alert went out and 182 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 2012-05-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1685 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, Slidell Radar S, LA at 12:00Z on 2012-05-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 118 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
1685 J/kg
Mixed-layer CIN
-13 J/kg
Mixed-layer LCL
500 m above ground
0-6 km bulk shear
28 kt
0-1 km storm-relative helicity
118 m²/s²
0-3 km storm-relative helicity
201 m²/s²
Significant tornado parameter
0.0
Supercell composite
5.7

Open this sounding in Storm Lab

The text

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

075 
WUUS54 KMOB 121928
SVRMOB
ALC129-122030-
/O.NEW.KMOB.SV.W.0054.120512T1928Z-120512T2030Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOBILE AL
228 PM CDT SAT MAY 12 2012

THE NATIONAL WEATHER SERVICE IN MOBILE HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHERN WASHINGTON COUNTY IN SOUTHWEST ALABAMA...

* UNTIL 330 PM CDT

* AT 222 PM CDT...A SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER
  SIZE HAIL AND DAMAGING WINDS OVER 60 MPH WAS LOCATED 11 MILES EAST
  OF LEAKESVILLE...OR 4 MILES SOUTHWEST OF DEER PARK...AND MOVING
  NORTHEAST AT 15 MPH.

* LOCATIONS IMPACTED INCLUDE...
  SIMS CHAPEL...        VINEGAR BEND...       TIBBIE...
  MCINTOSH...           MALCOLM...            DEER PARK...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FREQUNET CLOUD TO GROUND LIGHTNING IS ALSO OCCURRING WITH THIS STORM.
MOVE INDOORS IMMEDIATELY! IF YOU CAN HEAR THUNDER...YOU ARE CLOSE
ENOUGH TO BE STRUCK BY LIGHTNING.

&&

LAT...LON 3152 8824 3119 8797 3113 8843 3128 8844
TIME...MOT...LOC 1924Z 243DEG 14KT 3119 8837

$$
2 follow-up statements
198 
WWUS54 KMOB 121942
SVSMOB

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOBILE AL
242 PM CDT SAT MAY 12 2012

ALC129-122030-
/O.CON.KMOB.SV.W.0054.000000T0000Z-120512T2030Z/
WASHINGTON AL-
242 PM CDT SAT MAY 12 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 330 PM CDT
FOR SOUTHERN WASHINGTON COUNTY...

AT 236 PM CDT...A SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER
SIZE HAIL AND DAMAGING WINDS OVER 60 MPH WAS LOCATED 13 MILES NORTH
OF CITRONELLE...OR 3 MILES NORTHEAST OF DEER PARK...MOVING NORTHEAST
AT 20 MPH.

LOCATIONS IMPACTED INCLUDE...
  SIMS CHAPEL...        VINEGAR BEND...       TIBBIE...
  MCINTOSH...           MALCOLM...            DEER PARK...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS IS A DANGEROUS STORM. PREPARE FOR DAMAGING WINDS. PEOPLE OUTSIDE
SHOULD MOVE INSIDE A STRONG BUILDING BUT AWAY FROM WINDOWS.

TO REPORT SEVERE WEATHER...CALL (800) 284-9059.

&&

LAT...LON 3114 8834 3130 8843 3152 8824 3119 8797
TIME...MOT...LOC 1941Z 241DEG 18KT 3126 8826

$$
114 
WWUS54 KMOB 122009
SVSMOB

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOBILE AL
309 PM CDT SAT MAY 12 2012

ALC129-122018-
/O.CAN.KMOB.SV.W.0054.000000T0000Z-120512T2030Z/
WASHINGTON AL-
309 PM CDT SAT MAY 12 2012

...THE SEVERE THUNDERSTORM WARNING HAS BEEN CANCELLED FOR SOUTHERN
WASHINGTON COUNTY...

AT 304 PM CDT...THE STORM THAT PROMPTED THE WARNING FOR SOUTHERN 
WASHINGTON COUNTY HAD MOVED OUT OF THE WARNED AREA...THUS THE SEVERE 
THUNDERSTORM WARNING HAS BEEN CANCELLED.

TO REPORT SEVERE WEATHER...CALL (800) 284-9059.

LAT...LON 3114 8834 3130 8843 3152 8824 3119 8797
TIME...MOT...LOC 2008Z 241DEG 18KT 3133 8812

$$

The office that day

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

IssuedProductOfficeCountiesLasted
May 12, 12:31 PM CDTSevere Thunderstorm WarningMOBMobile, Washington59 min
May 12, 12:55 PM CDTTornado WarningMOBMobile, Washington50 min

Nearby

Severe Thunderstorm Warnings in Alabama, 2012Every severe thunderstorm 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.