Alert archive / Mississippi / Tornado Warnings in 2011

Tornado Warning 111, NWS Mobile, AL

September 4, 2011Greene County, Mississippi

NWS Mobile, AL issued this tornado warning at Sep 4, 2011, 12:19 PM CDT for Greene County, Mississippi. It was in force for 56 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
Sep 4, 2011, 12:19 PM CDT (17:19 UTC)
Expired
Sep 4, 2011, 1:15 PM CDT
In force
56 min
Issued by
NWS Mobile, AL
Area
Storm-based polygon

County Greene County, MS

The radar

The Mobile radar (KMOB), 81 km from the middle of the area, began a volume at 17:21 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 watch it was issued in

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

IssuedProductOfficeLasted
Sep 4, 5:05 AM CDTTornado WatchSPC11 hr

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 12:00Z, 5.3 hours before the alert went out and 155 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 2011-09-04Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2528 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 2011-09-04The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 249 square meters per square second.193958Sfc1 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
2528 J/kg
Mixed-layer CIN
-8 J/kg
Mixed-layer LCL
473 m above ground
0-6 km bulk shear
33 kt
0-1 km storm-relative helicity
249 m²/s²
0-3 km storm-relative helicity
287 m²/s²
Significant tornado parameter
3.0
Supercell composite
18.9

Open this sounding in Storm Lab

The text

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

327 
WFUS54 KMOB 041719
TORMOB
MSC041-041815-
/O.NEW.KMOB.TO.W.0111.110904T1719Z-110904T1815Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE MOBILE AL
1219 PM CDT SUN SEP 4 2011

THE NATIONAL WEATHER SERVICE IN MOBILE HAS ISSUED A

* TORNADO WARNING FOR...
  NORTHERN GREENE COUNTY IN SOUTHEAST MISSISSIPPI...

* UNTIL 115 PM CDT

* AT 1216 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO 4 MILES
  NORTHWEST OF LEAKESVILLE...OR 13 MILES WEST OF VINEGAR BEND...
  MOVING NORTH AT 30 MPH.

* LOCATIONS IMPACTED INCLUDE...
  KITTRELL...           OLD AVERA...          CLARK...
  CARSON CITY...        BRADLEY...            JONATHAN...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

IF IN MANUFACTURED HOMES OR VEHICLES...EVACUATE THEM AND GET INSIDE A
SUBSTANTIAL SHELTER. IF NO SHELTER IS AVAILABLE...LIE FLAT IN THE
NEAREST DITCH OR OTHER LOW SPOT AND COVER YOUR HEAD WITH YOUR HANDS.

A TORNADO WATCH REMAINS IN EFFECT UNTIL 400 PM CDT SUNDAY AFTERNOON
FOR SOUTHWESTERN ALABAMA AND NORTHWEST FLORIDA AND SOUTHEAST
MISSISSIPPI.

&&

LAT...LON 3135 8875 3143 8872 3143 8854 3119 8848
      3116 8868
TIME...MOT...LOC 1719Z 172DEG 25KT 3122 8859

$$
1 follow-up statement
144 
WWUS54 KMOB 041814
SVSMOB

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOBILE AL
114 PM CDT SUN SEP 4 2011

MSC041-041821-
/O.EXP.KMOB.TO.W.0111.000000T0000Z-110904T1815Z/
GREENE MS-
114 PM CDT SUN SEP 4 2011

...THE TORNADO WARNING FOR NORTHERN GREENE COUNTY WILL EXPIRE AT 115
PM CDT...

THE STORMS THAT PROMPTED THE WARNING HAVE LOST THEIR TIGHT ROTATION 
CHARACTERISTICS.  THEREFORE...THE WARNING HAS BEEN ALLOWED TO EXPIRE 
AT THIS TIME.  NEW WARNINGS MAY BE NECESSARY FOR NEW DEVELOPMENT 
ALONG THE SOUTHERN FLANK.

A TORNADO WATCH REMAINS IN EFFECT UNTIL 400 PM CDT SUNDAY AFTERNOON
FOR SOUTHWESTERN ALABAMA AND NORTHWEST FLORIDA AND SOUTHEAST
MISSISSIPPI.

LAT...LON 3135 8875 3143 8872 3143 8854 3119 8848
      3116 8868
TIME...MOT...LOC 1811Z 172DEG 25KT 3158 8865

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 3, 7:53 PM CDTAreal Flood WarningMOBGeorge, Greene, Perry, Stone6 hr
Sep 4, 12:59 AM CDTTornado WarningMOBGeorge61 min
Sep 4, 1:09 AM CDTFlash Flood WarningMOBStone3 hr
Sep 4, 3:10 AM CDTTornado WarningMOBGeorge50 min
Sep 4, 8:40 AM CDTTornado WarningMOBGreene, Perry35 min
Sep 4, 9:14 AM CDTTornado WarningMOBPerry, Wayne46 min
Sep 4, 9:54 AM CDTRiver Flood WarningMOBGeorge, Greene, Wayne25 hr
Sep 4, 11:13 AM CDTTornado WarningMOBPerry62 min
Sep 4, 11:19 AM CDTTornado WarningMOBGreene, Perry56 min
Sep 4, 11:41 AM CDTTornado WarningMOBGreene, Wayne64 min
Sep 4, 1:18 PM CDTTornado WarningMOBWayne42 min
Sep 4, 1:22 PM CDTFlash Flood WarningMOBWayne3 hr
Sep 4, 1:57 PM CDTFlash Flood WarningMOBGeorge, Greene3 hr
Sep 4, 2:01 PM CDTTornado WarningMOBWayne59 min

Nearby

Tornado Warnings in Mississippi, 2011Every tornado warning in 2011Tornadoes in 2011

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.