Alert archive / Alabama / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 75, NWS Birmingham, AL

March 31, 2012Blount County, Alabama

NWS Birmingham, AL issued this severe thunderstorm warning at Mar 31, 2012, 5:46 PM CDT for Blount County, Alabama. It was in force for 44 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: Mar 31, 2012, 5:46 PM CDT (22:46 UTC)
Expired: Mar 31, 2012, 6:30 PM CDT
In force: 44 min
Issued by: NWS Birmingham, AL
Area: Storm-based polygon

County Blount County, AL

The radar

The Birmingham radar (KBMX), 82 km from the middle of the area, began a volume at 22:48 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
Mar 31, 6:29 PM CDT	HAIL 1	2 Ne Oneonta, AL	QUARTER SIZED HAIL ON COUNTY ROAD 39. CORRECTED.
Mar 31, 6:35 PM CDT	HAIL 0.5	7 Ese Oneonta, AL	HALF INCH HAIL REPORTED SOUTHEAST OF ONEONTA.

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.

Issued	Product	Office	Lasted
Mar 31, 5:04 PM CDT	Severe Thunderstorm Watch	SPC	3 hr

The nearest sounding before it

Birmingham, AL (KBMX), launched 12:00Z, 10.8 hours before the alert went out and 82 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: 1095 J/kg
Mixed-layer CIN: -10 J/kg
Mixed-layer LCL: 580 m above ground
0-6 km bulk shear: 20 kt
0-1 km storm-relative helicity: 24 m²/s²
0-3 km storm-relative helicity: 36 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.5

Open this sounding in Storm Lab

The text

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

400 
WUUS54 KBMX 312246
SVRBMX
ALC009-312330-
/O.NEW.KBMX.SV.W.0075.120331T2246Z-120331T2330Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE BIRMINGHAM AL
546 PM CDT SAT MAR 31 2012

THE NATIONAL WEATHER SERVICE IN BIRMINGHAM HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHERN BLOUNT COUNTY IN ALABAMA...

* UNTIL 630 PM CDT

* AT 544 PM CDT...THE NATIONAL WEATHER SERVICE INDICATED A SEVERE
  THUNDERSTORM CAPABLE OF PRODUCING PING PONG BALL SIZE HAIL...AND
  DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS LOCATED NEAR
  BLOUNT SPRINGS...OR 14 MILES SOUTH OF CULLMAN...AND MOVING
  SOUTHEAST AT 25 MPH.

* LOCATIONS IMPACTED INCLUDE...
  CLEVELAND...ONEONTA...BLOUNT SPRINGS...BANGOR...HAYDEN...NECTAR...
  COUNTY LINE AND LOCUST FORK.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FOR YOUR PROTECTION...MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF
YOUR HOME OR BUSINESS.

&&

TO REPORT SEVERE WEATHER...
CALL 1-800-856-0758.

LAT...LON 3395 8636 3394 8637 3394 8632 3391 8635
      3389 8634 3382 8643 3380 8658 3377 8658
      3377 8665 3384 8676 3384 8691 3391 8693
      3396 8684 3396 8680 3406 8671
TIME...MOT...LOC 2246Z 305DEG 22KT 3397 8684

$$

56

The office that day

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

Issued	Product	Office	Counties	Lasted
Mar 31, 4:27 AM CDT	Special Weather Statement	BMX	Lowndes	48 min
Mar 31, 5:18 AM CDT	Special Weather Statement	BMX	Montgomery	42 min
Mar 31, 5:27 AM CDT	Areal Flood Advisory	BMX	Lowndes, Montgomery	3 hr
Mar 31, 5:33 AM CDT	Special Weather Statement	BMX	Russell	42 min
Mar 31, 5:56 AM CDT	Dense Fog Advisory	BMX	Fayette, Lamar, Marion, Walker, Winston	3 hr
Mar 31, 6:11 AM CDT	Special Weather Statement	BMX	Bullock, Macon, Russell	49 min
Mar 31, 6:48 AM CDT	Areal Flood Advisory	BMX	Barbour, Bullock, Macon, Pike, Russell	117 min
Mar 31, 7:32 AM CDT	Flash Flood Warning	BMX	Lowndes, Montgomery	3 hr
Mar 31, 4:23 PM CDT	Special Weather Statement	BMX	Winston	37 min
Mar 31, 4:39 PM CDT	Severe Thunderstorm Warning	BMX	Winston	36 min
Mar 31, 4:48 PM CDT	Special Weather Statement	BMX	Walker	27 min
Mar 31, 5:08 PM CDT	Severe Thunderstorm Warning	BMX	Walker, Winston	52 min
Mar 31, 5:32 PM CDT	Severe Thunderstorm Warning	BMX	Walker, Winston	43 min
Mar 31, 5:38 PM CDT	Severe Thunderstorm Warning	BMX	Blount, Etowah	37 min
Mar 31, 5:49 PM CDT	Special Weather Statement	BMX	Cherokee	26 min
Mar 31, 5:52 PM CDT	Severe Thunderstorm Warning	BMX	Jefferson, Walker	38 min
Mar 31, 6:08 PM CDT	Severe Thunderstorm Warning	BMX	Blount, Calhoun, Etowah, St. Clair	52 min
Mar 31, 6:11 PM CDT	Severe Thunderstorm Warning	BMX	Walker	49 min
Mar 31, 6:19 PM CDT	Severe Thunderstorm Warning	BMX	Winston	41 min
Mar 31, 6:35 PM CDT	Severe Thunderstorm Warning	BMX	Jefferson, Walker	40 min
Mar 31, 6:37 PM CDT	Severe Thunderstorm Warning	BMX	Calhoun, Clay, Cleburne, Randolph, St. Clair, Talladega	38 min
Mar 31, 6:57 PM CDT	Severe Thunderstorm Warning	BMX	Walker	33 min
Mar 31, 6:58 PM CDT	Severe Thunderstorm Warning	BMX	Winston	32 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.