Alert archive / Alabama / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 122, NWS Mobile, AL

May 12, 2021Mobile County, Alabama

NWS Mobile, AL issued this severe thunderstorm warning at May 12, 2021, 4:56 AM CDT for Mobile County, Alabama. It was in force for 24 min. 1 report 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: May 12, 2021, 4:56 AM CDT (09:56 UTC)
Expired: May 12, 2021, 5:20 AM CDT
In force: 24 min
Issued by: NWS Mobile, AL
Area: Storm-based polygon
Tornado: Possible
Hail: 0.75 in
Wind: 60.0 mph

County Mobile County, AL

The radar

The Mobile radar (KMOB), 47 km from the middle of the area, began a volume at 09:58 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
May 12, 5:10 AM CDT	MARINE TSTM WIND 44	East End Of Dauphin, AL	MARINE THUNDERSTORM WIND GUST OF 38KTS MEASURED AT C-MAN STATION DPIA1.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 00:00Z, 9.9 hours before the alert went out and 143 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: 618 J/kg
Mixed-layer CIN: -59 J/kg
Mixed-layer LCL: 924 m above ground
0-6 km bulk shear: 32 kt
0-1 km storm-relative helicity: 135 m²/s²
0-3 km storm-relative helicity: 212 m²/s²
Significant tornado parameter: 0.3
Supercell composite: 4.7

Open this sounding in Storm Lab

The text

As transmitted.

135 
WUUS54 KMOB 120956
SVRMOB
ALC097-121100-
/O.NEW.KMOB.SV.W.0122.210512T0956Z-210512T1100Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mobile AL
456 AM CDT Wed May 12 2021

The National Weather Service in Mobile has issued a

* Severe Thunderstorm Warning for...
  South central Mobile County in southwestern Alabama...

* Until 600 AM CDT.

* At 456 AM CDT, a severe thunderstorm was located 6 miles west of
  Dauphin Island, moving east at 25 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

  IMPACT...Expect damage to roofs, siding, and trees.

* Locations impacted include...
  Dauphin Island and Alabama Port. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 3019 8831 3037 8830 3036 8806 3017 8806
TIME...MOT...LOC 0956Z 277DEG 24KT 3028 8822 

TORNADO...POSSIBLE
HAIL...<.75IN
WIND...60MPH
 
$$

1 follow-up statement

407 
WWUS54 KMOB 121020
SVSMOB

Severe Weather Statement
National Weather Service Mobile AL
520 AM CDT Wed May 12 2021

ALC097-121030-
/O.CAN.KMOB.SV.W.0122.000000T0000Z-210512T1100Z/
Mobile AL-
520 AM CDT Wed May 12 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTH CENTRAL MOBILE COUNTY IS
CANCELLED...
        
The storm which prompted the warning has weakened below severe
limits, and has exited the warned area. Therefore, the warning has
been cancelled.

LAT...LON 3019 8831 3037 8830 3036 8806 3017 8806
TIME...MOT...LOC 1018Z 277DEG 24KT 3026 8804 

$$

The office that day

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

Issued	Product	Office	Counties	Lasted
May 12, 2:55 AM CDT	Special Weather Statement	MOB	Washington	65 min
May 12, 3:31 AM CDT	Special Weather Statement	MOB	Baldwin, Mobile	44 min
May 12, 3:46 AM CDT	Flash Flood Warning	MOB	Clarke, Washington	4 hr
May 12, 4:06 AM CDT	Special Weather Statement	MOB	Baldwin, Mobile	54 min
May 12, 4:12 AM CDT	Areal Flood Advisory	MOB	Baldwin, Mobile	3 hr
May 12, 4:20 AM CDT	Special Marine Warning	MOB		85 min
May 12, 4:41 AM CDT	Special Marine Warning	MOB		94 min
May 12, 5:01 AM CDT	Areal Flood Advisory	MOB	Baldwin, Escambia	3 hr
May 12, 5:04 AM CDT	Special Weather Statement	MOB	Baldwin, Escambia	86 min
May 12, 6:01 AM CDT	Severe Thunderstorm Warning	MOB	Conecuh, Covington, Escambia	44 min
May 12, 6:24 AM CDT	Special Marine Warning	MOB		96 min
May 12, 6:29 AM CDT	Severe Thunderstorm Warning	MOB	Covington	64 min
May 12, 6:35 AM CDT	Special Marine Warning	MOB		55 min
May 12, 6:52 AM CDT	Areal Flood Advisory	MOB	Conecuh, Covington, Escambia	3 hr
May 12, 6:56 AM CDT	Severe Thunderstorm Warning	MOB	Covington, Crenshaw	35 min
May 12, 7:18 AM CDT	Special Marine Warning	MOB		87 min

Nearby

Severe Thunderstorm Warnings in Alabama, 2021 Every severe thunderstorm warning 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.