Alert archive / Alabama / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 157, NWS Mobile, AL

July 30, 2012Covington County, Alabama

NWS Mobile, AL issued this severe thunderstorm warning at Jul 30, 2012, 6:34 PM CDT for Covington County, Alabama. It was in force for 47 min. 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 30, 2012, 6:34 PM CDT (23:34 UTC)
Expired: Jul 30, 2012, 7:21 PM CDT
In force: 47 min
Issued by: NWS Mobile, AL
Area: Storm-based polygon

County Covington County, AL

The radar

The Eglin Afb radar (KEVX), 81 km from the middle of the area, began a volume at 23:35 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 30, 6:49 PM CDT	HAIL 1.75	Carolina, AL	QUARTER TO GOLF BALL SIZE HAIL REPORTED COVERING GROUND.

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

The nearest sounding before it

Tallahassee Rgnl, FL (KTLH), launched 12:00Z, 11.6 hours before the alert went out and 222 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: 3159 J/kg
Mixed-layer CIN: -15 J/kg
Mixed-layer LCL: 518 m above ground
0-6 km bulk shear: 17 kt
0-1 km storm-relative helicity: 60 m²/s²
0-3 km storm-relative helicity: 73 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.

684 
WUUS54 KMOB 302334
SVRMOB
ALC039-310030-
/O.NEW.KMOB.SV.W.0157.120730T2334Z-120731T0030Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOBILE AL
634 PM CDT MON JUL 30 2012

THE NATIONAL WEATHER SERVICE IN MOBILE HAS ISSUED A

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

* UNTIL 730 PM CDT

* AT 627 PM CDT...A SEVERE THUNDERSTORM CAPABLE OF PRODUCING GOLF
  BALL SIZE HAIL AND DAMAGING WINDS OVER 60 MPH WAS LOCATED 4 MILES
  SOUTH OF ANDALUSIA...OR NEAR LIBERTYVILLE...AND MOVING SOUTH AT 25
  MPH.

* LOCATIONS IMPACTED INCLUDE...
  SANFORD...            LIBERTYVILLE...       CAROLINA...
  ANDALUSIA...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

HAIL UP TO NEAR ONE INCH IN DIAMETER HAS BEEN REPORTED JUST SOUTH OF
ANDALUSIA IN ASSOCIATION WITH THIS STORM...AND RADAR INDICATES THAT 
EVEN LARGER HAIL IS POSSIBLE.

&&

LAT...LON 3100 8637 3101 8668 3133 8656 3130 8635
TIME...MOT...LOC 2331Z 011DEG 21KT 3123 8648

$$

2 follow-up statements

375 
WWUS54 KMOB 302346
SVSMOB

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOBILE AL
646 PM CDT MON JUL 30 2012

ALC039-310030-
/O.CON.KMOB.SV.W.0157.000000T0000Z-120731T0030Z/
COVINGTON AL-
646 PM CDT MON JUL 30 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 730 PM CDT
FOR SOUTHWESTERN COVINGTON COUNTY...

AT 641 PM CDT...TRAINED WEATHER SPOTTERS REPORT A SEVERE THUNDERSTORM
PRODUCING QUARTER TO GOLF BALL SIZE HAIL LOCATED ABOUT 7 MILES SOUTH OF
ANDALUSIA...OR 2 MILES SOUTHEAST OF CAROLINA...MOVING SOUTHWEST AT 20 MPH.
WIND GUSTS TO 60 MPH WILL ALSO BE POSSIBLE WITH THIS STORM. 
 
LOCATIONS IMPACTED INCLUDE...
  SANFORD...            LIBERTYVILLE...       CAROLINA...
  ANDALUSIA...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3100 8637 3101 8668 3133 8656 3130 8635
TIME...MOT...LOC 2345Z 023DEG 15KT 3119 8652

$$

953 
WWUS54 KMOB 310021
SVSMOB

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOBILE AL
721 PM CDT MON JUL 30 2012

ALC039-310030-
/O.CAN.KMOB.SV.W.0157.000000T0000Z-120731T0030Z/
COVINGTON AL-
721 PM CDT MON JUL 30 2012

...THE SEVERE THUNDERSTORM WARNING HAS BEEN CANCELLED FOR
SOUTHWESTERN COVINGTON COUNTY...

AT 718 PM CDT...THE STORM THAT PROMPTED THE WARNING FOR SOUTHWESTERN
COVINGTON COUNTY HAS WEAKENED SLIGHTLY...TO BELOW SEVERE LIMITS...THUS
THE SEVERE THUNDERSTORM WARNING HAS BEEN CANCELLED.

ADDITIONAL STRONG STORMS HAVE DEVELOPED HOWEVER ALONG BOTH THE EASTERN 
AND WESTERN BORDERS OF THE COUNTY AND ADDITIONAL STATEMENTS OR WARNINGS
WILL BE POSSIBLE.  

LAT...LON 3100 8637 3101 8668 3133 8656 3130 8635
TIME...MOT...LOC 0020Z 011DEG 21KT 3095 8654

$$

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 30, 10:28 AM CDT	Heat Advisory	MOB		5 hr
Jul 30, 12:52 PM CDT	Special Marine Warning	MOB		68 min
Jul 30, 1:25 PM CDT	Special Marine Warning	MOB		65 min
Jul 30, 2:02 PM CDT	Special Marine Warning	MOB		88 min
Jul 30, 2:27 PM CDT	Severe Thunderstorm Warning	MOB	Mobile, Washington	17 min
Jul 30, 2:28 PM CDT	Special Marine Warning	MOB		92 min
Jul 30, 2:34 PM CDT	Special Marine Warning	MOB		86 min
Jul 30, 2:49 PM CDT	Severe Thunderstorm Warning	MOB	Baldwin	56 min
Jul 30, 3:03 PM CDT	Special Marine Warning	MOB		87 min
Jul 30, 3:04 PM CDT	Severe Thunderstorm Warning	MOB	Baldwin	56 min
Jul 30, 3:30 PM CDT	Special Marine Warning	MOB		90 min
Jul 30, 3:38 PM CDT	Severe Thunderstorm Warning	MOB	Baldwin	67 min
Jul 30, 4:03 PM CDT	Special Marine Warning	MOB		87 min
Jul 30, 4:14 PM CDT	Severe Thunderstorm Warning	MOB	Mobile	61 min
Jul 30, 4:53 PM CDT	Special Marine Warning	MOB		97 min
Jul 30, 5:11 PM CDT	Severe Thunderstorm Warning	MOB	Covington	64 min
Jul 30, 5:21 PM CDT	Severe Thunderstorm Warning	MOB	Escambia	54 min

Nearby

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