Alert archive / Mississippi / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 221, NWS Mobile, AL

December 20, 20124 counties in Mississippi

NWS Mobile, AL issued this severe thunderstorm warning at Dec 20, 2012, 7:42 AM CST for 4 counties in Mississippi. It was in force for 63 min. 2 reports 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
Dec 20, 2012, 7:42 AM CST (13:42 UTC)
Expired
Dec 20, 2012, 8:45 AM CST
In force
63 min
Issued by
NWS Mobile, AL
Area
Storm-based polygon

Counties George County, MS, Greene County, MS, Perry County, MS, Stone County, MS

The radar

The Mobile radar (KMOB), 78 km from the middle of the area, began a volume at 13:42 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

TimeReportWhereRemark
Dec 20, 8:00 AM CSTTSTM WND DMG1 S New Augusta, MSTREES BLOCKING HWY 29 SOUTH OF NEW AUGUSTA.
Dec 20, 8:15 AM CSTTSTM WND DMGBenndale, MSDECK ROOF BLOWN OFF.

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

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Dec 20, 4:23 AM CSTTornado WatchSPC9 hr

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 12:00Z, 1.7 hours before the alert went out and 117 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 2012-12-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1181 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 2012-12-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 275 square meters per square second.1939587897Sfc1 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
1181 J/kg
Mixed-layer CIN
-4 J/kg
Mixed-layer LCL
506 m above ground
0-6 km bulk shear
47 kt
0-1 km storm-relative helicity
275 m²/s²
0-3 km storm-relative helicity
310 m²/s²
Significant tornado parameter
2.0
Supercell composite
9.6

Open this sounding in Storm Lab

The text

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

768 
WUUS54 KMOB 201342
SVRMOB
MSC039-041-111-131-201445-
/O.NEW.KMOB.SV.W.0221.121220T1342Z-121220T1445Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOBILE AL
742 AM CST THU DEC 20 2012

THE NATIONAL WEATHER SERVICE IN MOBILE HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  GEORGE COUNTY IN SOUTHEAST MISSISSIPPI...
  GREENE COUNTY IN SOUTHEAST MISSISSIPPI...
  PERRY COUNTY IN SOUTHEAST MISSISSIPPI...
  STONE COUNTY IN SOUTHEAST MISSISSIPPI...

* UNTIL 845 AM CST

* AT 737 AM CST...A LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING
  DAMAGING WINDS OVER 60 MPH WERE LOCATED ALONG A LINE EXTENDING FROM
  11 MILES EAST OF RICHTON TO 24 MILES NORTHWEST OF DIAMONDHEAD...AND
  MOVING EAST AT 50 MPH.

* LOCATIONS IMPACTED INCLUDE...
  MCLAIN...             LEAKESVILLE...        NEW AUGUSTA...
  BEAUMONT...           WIGGINS...            PERKINSTON...
  MCHENRY...            LUCEDALE...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A TORNADO WATCH REMAINS IN EFFECT UNTIL NOON CST THURSDAY FOR
SOUTHWESTERN ALABAMA AND NORTHWEST FLORIDA AND SOUTHEAST MISSISSIPPI.

&&

LAT...LON 3092 8914 3113 8915 3143 8886 3144 8845
      3143 8845 3075 8842 3068 8934 3091 8935
TIME...MOT...LOC 1342Z 259DEG 42KT 3140 8869 3072 8947

$$
2 follow-up statements
550 
WWUS54 KMOB 201405
SVSMOB

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOBILE AL
805 AM CST THU DEC 20 2012

MSC039-041-111-131-201445-
/O.CON.KMOB.SV.W.0221.000000T0000Z-121220T1445Z/
STONE MS-PERRY MS-GREENE MS-GEORGE MS-
805 AM CST THU DEC 20 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 845 AM CST
FOR GEORGE...GREENE...SOUTHERN PERRY AND STONE COUNTIES...

AT 800 AM CST...A LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING
DAMAGING WINDS OVER 60 MPH WERE LOCATED ALONG A LINE EXTENDING FROM
17 MILES SOUTH OF WAYNESBORO TO 16 MILES WEST OF WIGGINS...MOVING
EAST AT 50 MPH.

LOCATIONS IMPACTED INCLUDE...
  MCLAIN...             LEAKESVILLE...        BEAUMONT...
  WIGGINS...            PERKINSTON...         MCHENRY...
  LUCEDALE...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A TORNADO WATCH REMAINS IN EFFECT UNTIL NOON CST THURSDAY FOR
SOUTHWESTERN ALABAMA AND NORTHWEST FLORIDA AND SOUTHEAST MISSISSIPPI.

&&

LAT...LON 3092 8914 3111 8915 3141 8877 3144 8864
      3144 8845 3075 8842 3073 8888 3072 8888
      3068 8934 3091 8935
TIME...MOT...LOC 1405Z 259DEG 42KT 3144 8852 3084 8934

$$
226 
WWUS54 KMOB 201435
SVSMOB

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOBILE AL
835 AM CST THU DEC 20 2012

MSC039-041-111-131-201445-
/O.CON.KMOB.SV.W.0221.000000T0000Z-121220T1445Z/
STONE MS-PERRY MS-GREENE MS-GEORGE MS-
835 AM CST THU DEC 20 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 845 AM CST
FOR GEORGE...GREENE...SOUTHERN PERRY AND STONE COUNTIES...

AT 833 AM CST...A LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING
DAMAGING WINDS OVER 60 MPH WERE LOCATED ALONG A LINE EXTENDING FROM
14 MILES SOUTHWEST OF CHATOM TO 11 MILES SOUTHWEST OF WIGGINS...
MOVING EAST AT 50 MPH.

LOCATIONS IMPACTED INCLUDE...
  MCLAIN...             LEAKESVILLE...        BEAUMONT...
  WIGGINS...            PERKINSTON...         MCHENRY...
  LUCEDALE...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A TORNADO WATCH REMAINS IN EFFECT UNTIL NOON CST THURSDAY FOR
SOUTHWESTERN ALABAMA AND NORTHWEST FLORIDA AND SOUTHEAST MISSISSIPPI.

&&

LAT...LON 3092 8914 3111 8915 3141 8877 3144 8866
      3143 8845 3075 8843 3073 8888 3072 8888
      3068 8934 3091 8935
TIME...MOT...LOC 1436Z 259DEG 42KT 3136 8841 3076 8923

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Dec 20, 6:40 AM CSTTornado WarningMOBGreene50 min
Dec 20, 7:12 AM CSTSevere Thunderstorm WarningMOBWayne63 min

Nearby

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