Alert archive / Alabama / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 55, NWS Mobile, AL

April 27, 2011Wilcox County, Alabama

NWS Mobile, AL issued this severe thunderstorm warning at Apr 27, 2011, 9:42 PM CDT for Wilcox County, Alabama. It was in force for 33 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
Apr 27, 2011, 9:42 PM CDT (02:42 UTC)
Expired
Apr 27, 2011, 10:15 PM CDT
In force
33 min
Issued by
NWS Mobile, AL
Area
Storm-based polygon

County Wilcox County, AL

The radar

The Birmingham radar (KBMX), 134 km from the middle of the area, began a volume at 02:44 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
Apr 27, 1:42 PM CDTTornado Watch PDSSPC8 hr
Apr 27, 9:42 PM CDTTornado WatchSPC4 hr

The nearest sounding before it

Birmingham, AL (KBMX), launched 00:00Z, 2.7 hours before the alert went out and 135 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, Birmingham, AL at 00:00Z on 2011-04-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3065 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, Birmingham, AL at 00:00Z on 2011-04-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 448 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
3065 J/kg
Mixed-layer CIN
-4 J/kg
Mixed-layer LCL
711 m above ground
0-6 km bulk shear
73 kt
0-1 km storm-relative helicity
448 m²/s²
0-3 km storm-relative helicity
480 m²/s²
Significant tornado parameter
9.6
Supercell composite
33.6

Open this sounding in Storm Lab

The text

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

976 
WUUS54 KMOB 280242
SVRMOB
ALC131-280345-
/O.NEW.KMOB.SV.W.0055.110428T0242Z-110428T0345Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOBILE AL
942 PM CDT WED APR 27 2011

THE NATIONAL WEATHER SERVICE IN MOBILE HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTHWESTERN WILCOX COUNTY IN SOUTH CENTRAL ALABAMA...

* UNTIL 1045 PM CDT

* AT 938 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING QUARTER SIZE
  HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH.  THESE STORMS WERE
  LOCATED ALONG A LINE EXTENDING FROM 16 MILES EAST OF LINDEN TO 7
  MILES SOUTHEAST OF LINDEN TO 13 MILES EAST OF BUTLER...AND MOVING
  EAST AT 35 MPH.

* SEVERE THUNDERSTORMS WILL BE NEAR...
  PINE HILL AROUND 1020 PM CDT...
  ANNE MARIE AND ANNE MANIE AROUND 1025 PM CDT...
  YELLOW BLUFF AROUND 1035 PM CDT...
  BOYKIN AND CANTON BEND AROUND 1045 PM CDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A TORNADO WATCH REMAINS IN EFFECT FOR THE WARNED AREA. IF A TORNADO
IS SPOTTED... ACT QUICKLY AND MOVE TO A PLACE OF SAFETY IN A STURDY
STRUCTURE...SUCH AS A BASEMENT OR SMALL INTERIOR ROOM.

&&

LAT...LON 3221 8736 3220 8732 3208 8718 3205 8722
      3187 8761 3189 8767 3201 8767 3202 8763
      3214 8762 3215 8753 3227 8753 3228 8751
      3228 8743
TIME...MOT...LOC 0242Z 276DEG 29KT 3231 8749 3220 8770
          3212 8796

$$
1 follow-up statement
917 
WWUS54 KMOB 280315
SVSMOB

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOBILE AL
1015 PM CDT WED APR 27 2011

ALC131-280324-
/O.CAN.KMOB.SV.W.0055.000000T0000Z-110428T0345Z/
WILCOX AL-
1015 PM CDT WED APR 27 2011

...THE SEVERE THUNDERSTORM WARNING FOR NORTHWESTERN WILCOX COUNTY IS
CANCELLED...

A TORNADO WATCH REMAINS IN EFFECT UNTIL 200 AM CDT THURSDAY MORNING
FOR SOUTHWESTERN ALABAMA AND SOUTHEAST MISSISSIPPI.

LAT...LON 3221 8736 3220 8732 3208 8718 3205 8722
      3187 8761 3189 8767 3201 8767 3202 8763
      3214 8762 3215 8753 3227 8753 3228 8751
      3228 8743
TIME...MOT...LOC 0314Z 276DEG 29KT 3228 8719 3217 8740
          3209 8766

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 27, 7:21 PM CDTTornado Warning EmergencyMOBChoctaw39 min
Apr 27, 8:00 PM CDTTornado WarningMOBChoctaw60 min
Apr 28, 1:02 AM CDTTornado WarningMOBCovington13 min
Apr 28, 3:27 AM CDTSpecial Marine WarningMOB48 min

Nearby

Severe Thunderstorm Warnings in Alabama, 2011Every severe thunderstorm warning 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.