Alert archive / Alabama / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 169, NWS Mobile, AL

August 3, 2012Covington County, Alabama

NWS Mobile, AL issued this severe thunderstorm warning at Aug 3, 2012, 4:20 PM CDT for Covington County, Alabama. It was in force for 25 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
Aug 3, 2012, 4:20 PM CDT (21:20 UTC)
Expired
Aug 3, 2012, 4:45 PM CDT
In force
25 min
Issued by
NWS Mobile, AL
Area
Storm-based polygon

County Covington County, AL

The radar

The Eglin Afb radar (KEVX), 77 km from the middle of the area, began a volume at 21:23 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

Tallahassee Rgnl, FL (KTLH), launched 12:00Z, 9.3 hours before the alert went out and 219 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, Tallahassee Rgnl, FL at 12:00Z on 2012-08-03Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2919 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, Tallahassee Rgnl, FL at 12:00Z on 2012-08-03The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -41 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
2919 J/kg
Mixed-layer CIN
-3 J/kg
Mixed-layer LCL
540 m above ground
0-6 km bulk shear
12 kt
0-1 km storm-relative helicity
-41 m²/s²
0-3 km storm-relative helicity
14 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.

416 
WUUS54 KMOB 032120
SVRMOB
ALC039-032145-
/O.NEW.KMOB.SV.W.0169.120803T2120Z-120803T2145Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOBILE AL
420 PM CDT FRI AUG 3 2012

THE NATIONAL WEATHER SERVICE IN MOBILE HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTH CENTRAL COVINGTON COUNTY IN SOUTH CENTRAL ALABAMA...

* UNTIL 445 PM CDT

* AT 415 PM CDT...A SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER
  SIZE HAIL AND DAMAGING WINDS NEAR 60 MPH WAS LOCATED 11 MILES
  NORTHWEST OF FLORALA...OR 9 MILES NORTH OF LAUREL HILL...AND MOVING
  SLOWLY SOUTHEAST AT 6 MPH.

* LOCATIONS IMPACTED INCLUDE...
  RURAL SOUTH CENTRAL COVINGTON COUNTY

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3102 8634 3101 8658 3114 8661 3120 8641
TIME...MOT...LOC 2120Z 323DEG 7KT 3109 8647

$$
1 follow-up statement
390 
WWUS54 KMOB 032145
SVSMOB

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOBILE AL
445 PM CDT FRI AUG 3 2012

ALC039-032154-
/O.EXP.KMOB.SV.W.0169.000000T0000Z-120803T2145Z/
COVINGTON AL-
445 PM CDT FRI AUG 3 2012

...THE SEVERE THUNDERSTORM WARNING HAS BEEN ALLOWED TO EXPIRE FOR
SOUTH CENTRAL COVINGTON COUNTY...

AT 443 PM CDT...THE STORM THAT PROMPTED THE WARNING FOR SOUTH CENTRAL
COVINGTON COUNTY HAS WEAKENED TO BELOW SEVERE LIMITS...THUS THE
SEVERE THUNDERSTORM WARNING WILL BE ALLOWED TO EXPIRE AT 445 PM CDT.

WHILE NOT SEVERE...THUNDERSTORMS PERSISTING OVER COVINGTON COUNTY 
WILL STILL BE CAPABLE OF PRODUCING WINDS TO NEAR 50 MPH...SMALL HAIL 
TO THE SIZE OF NICKELS...AND DANGEROUS CLOUD TO GROUND LIGHTNING 
STRIKES THROUGH 6 PM.  

LAT...LON 3102 8634 3101 8658 3114 8661 3120 8641
TIME...MOT...LOC 2144Z 323DEG 7KT 3105 8644

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 3, 3:22 PM CDTAreal Flood AdvisoryMOBMobile113 min
Aug 3, 3:33 PM CDTSevere Thunderstorm WarningMOBMobile42 min
Aug 3, 4:40 PM CDTSevere Thunderstorm WarningMOBButler, Conecuh35 min
Aug 3, 5:12 PM CDTSevere Thunderstorm WarningMOBWashington20 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.