Alert archive / Alabama / Special Weather Statements in 2021

Special Weather Statement, NWS Birmingham, AL

July 6, 2021Walker County, Alabama

NWS Birmingham, AL issued this special weather statement at Jul 6, 2021, 5:21 PM CDT for Walker County, Alabama. It was in force for 39 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
Jul 6, 2021, 5:21 PM CDT (22:21 UTC)
Expired
Jul 6, 2021, 6:00 PM CDT
In force
39 min
Issued by
NWS Birmingham, AL

County Walker County, AL

The radar

The Birmingham radar (KBMX), 69 km from the middle of the area, began a volume at 22:20 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 nearest sounding before it

Birmingham, AL (KBMX), launched 12:00Z, 10.4 hours before the alert went out and 67 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 12:00Z on 2021-07-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 479 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Birmingham, AL at 12:00Z on 2021-07-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -41 square meters per square second.1939Sfc1 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
479 J/kg
Mixed-layer CIN
-5 J/kg
Mixed-layer LCL
593 m above ground
0-6 km bulk shear
18 kt
0-1 km storm-relative helicity
-41 m²/s²
0-3 km storm-relative helicity
-15 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

222 
WWUS84 KBMX 062221
SPSBMX

Special Weather Statement
National Weather Service Birmingham AL
521 PM CDT Tue Jul 6 2021
 
ALZ013-015-023-062300-
Fayette AL-Walker AL-Tuscaloosa AL-
521 PM CDT Tue Jul 6 2021

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHWESTERN WALKER...NORTH
CENTRAL TUSCALOOSA AND SOUTHEASTERN FAYETTE COUNTIES UNTIL 600 PM
CDT...

At 521 PM CDT, Doppler radar was tracking a strong thunderstorm near
Bankhead Lock And Dam, or 18 miles northeast of Holt, moving north at
25 mph.

Winds in excess of 40 mph will be possible with this storm.

Locations impacted include...
Oakman, Boley Springs, Bankhead Lock And Dam, Whitson, Wiley, The
Wye, Windham Springs and Corona.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

To report severe weather, contact your nearest law enforcement
agency. They will relay your report to the National Weather Service
office in Birmingham.

&&

LAT...LON 3373 8746 3371 8730 3348 8729 3348 8730
      3349 8730 3349 8733 3347 8734 3345 8733
      3345 8731 3344 8732 3341 8745 3364 8759
TIME...MOT...LOC 2221Z 164DEG 20KT 3349 8738 

$$

40/Sizemore

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 6, 3:46 PM CDTSpecial Weather StatementBMXAutauga, Elmore44 min
Jul 6, 4:28 PM CDTSpecial Weather StatementBMXAutauga, Chilton, Elmore47 min
Jul 6, 5:14 PM CDTSpecial Weather StatementBMXBibb, Chilton46 min
Jul 6, 5:56 PM CDTSpecial Weather StatementBMXChambers, Tallapoosa49 min

Nearby

Special Weather Statements in Alabama, 2021Every special weather statement in 2021

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.