Alert archive / Alabama / Special Weather Statements in 2021

Special Weather Statement, NWS Birmingham, AL

August 9, 2021Dallas County, Alabama

NWS Birmingham, AL issued this special weather statement at Aug 9, 2021, 2:49 PM CDT for Dallas County, Alabama. It was in force for 41 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
Aug 9, 2021, 2:49 PM CDT (19:49 UTC)
Expired
Aug 9, 2021, 3:30 PM CDT
In force
41 min
Issued by
NWS Birmingham, AL
Hail
0.00 in
Wind
40

County Dallas County, AL

The radar

The Birmingham radar (KBMX), 100 km from the middle of the area, began a volume at 19:51 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, 7.8 hours before the alert went out and 100 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 2021-08-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1644 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 12:00Z on 2021-08-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 52 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
1644 J/kg
Mixed-layer CIN
-36 J/kg
Mixed-layer LCL
893 m above ground
0-6 km bulk shear
13 kt
0-1 km storm-relative helicity
52 m²/s²
0-3 km storm-relative helicity
37 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

687 
WWUS84 KBMX 091949
SPSBMX

Special Weather Statement
National Weather Service Birmingham AL
249 PM CDT Mon Aug 9 2021
 
ALZ040>042-092030-
Autauga AL-Lowndes AL-Dallas AL-
249 PM CDT Mon Aug 9 2021

...A strong thunderstorm will impact portions of southwestern
Autauga, northwestern Lowndes and southeastern Dallas Counties
through 330 PM CDT...

At 249 PM CDT, Doppler radar was tracking a strong thunderstorm near
Selmont-West Selmont, moving east at 15 mph.

HAZARD...Winds in excess of 40 mph.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around 
         unsecured objects.

Locations impacted include...
Selma, Selmont-West Selmont, White Hall, Benton, Belknap, Gardner
Island, Tyler, Dallas Lake, Old Cahaba Park, Memorial Stadium, Robert
F. Henry Lock And Dam, Craig Field Aiport, Selma Drag Strip,
Collirene, Edmund Pettus Bridge and Selma University.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building. 

Torrential rainfall is also occurring with this storm and may lead to
localized flooding. Do not drive your vehicle through flooded
roadways.

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

&&

LAT...LON 3223 8715 3247 8703 3240 8670 3213 8680
TIME...MOT...LOC 1949Z 284DEG 14KT 3232 8701 

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...40 MPH

$$

25/Owen

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 9, 12:21 PM CDTSpecial Weather StatementBMXPerry24 min
Aug 9, 12:25 PM CDTSpecial Weather StatementBMXClay35 min
Aug 9, 12:42 PM CDTSpecial Weather StatementBMXEtowah33 min
Aug 9, 1:13 PM CDTSpecial Weather StatementBMXBibb32 min
Aug 9, 1:49 PM CDTSpecial Weather StatementBMXDallas41 min
Aug 9, 1:51 PM CDTSpecial Weather StatementBMXCherokee39 min
Aug 9, 2:05 PM CDTSpecial Weather StatementBMXDeKalb40 min
Aug 9, 2:28 PM CDTSpecial Weather StatementBMXRandolph32 min
Aug 9, 2:30 PM CDTSpecial Weather StatementBMXCherokee30 min
Aug 9, 3:02 PM CDTSpecial Weather StatementBMXChambers28 min
Aug 9, 3:48 PM CDTSpecial Weather StatementBMXClay27 min
Aug 9, 3:49 PM CDTSpecial Weather StatementBMXChambers26 min
Aug 9, 4:00 PM CDTSpecial Weather StatementBMXTalladega30 min
Aug 9, 4:21 PM CDTSpecial Weather StatementBMXTalladega24 min
Aug 9, 4:44 PM CDTSevere Thunderstorm WarningBMXTalladega31 min
Aug 9, 5:21 PM CDTSpecial Weather StatementBMXCalhoun39 min
Aug 9, 5:56 PM CDTSpecial Weather StatementBMXElmore34 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.