Alert archive / Alabama / Severe Thunderstorm Warnings in 2018

Severe Thunderstorm Warning 9, NWS Mobile, AL

April 7, 2018Baldwin County, Mobile County, Alabama

NWS Mobile, AL issued this severe thunderstorm warning at Apr 7, 2018, 3:41 AM CDT for Baldwin County, Mobile County, Alabama. It was in force for 19 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 7, 2018, 3:41 AM CDT (08:41 UTC)
Expired: Apr 7, 2018, 4:00 AM CDT
In force: 19 min
Issued by: NWS Mobile, AL
Area: Storm-based polygon
Tornado: Possible
Hail: 0.75 in
Wind: 60.0 mph

Counties Baldwin County, AL, Mobile County, AL

The radar

The Mobile radar (KMOB), 12 km from the middle of the area, began a volume at 08:44 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 nearest sounding before it

Slidell Radar S, LA (KSIL), launched 00:00Z, 8.7 hours before the alert went out and 155 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: 933 J/kg
Mixed-layer CIN: -12 J/kg
Mixed-layer LCL: 780 m above ground
0-6 km bulk shear: 34 kt
0-1 km storm-relative helicity: 144 m²/s²
0-3 km storm-relative helicity: 257 m²/s²
Significant tornado parameter: 0.5
Supercell composite: 5.7

Open this sounding in Storm Lab

The text

As transmitted.

966 
WUUS54 KMOB 070841
SVRMOB
ALC003-097-070930-
/O.NEW.KMOB.SV.W.0009.180407T0841Z-180407T0930Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mobile AL
341 AM CDT SAT APR 7 2018

The National Weather Service in Mobile has issued a

* Severe Thunderstorm Warning for...
  Central Mobile County in southwestern Alabama...
  West central Baldwin County in southwestern Alabama...

* Until 430 AM CDT

* At 340 AM CDT, a severe thunderstorm was located over Wilmer, or 14
  miles northwest of Midtown Mobile, moving east at 45 mph.

  HAZARD...60 mph wind gusts. 

  SOURCE...Radar indicated. 

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

* Locations impacted include...
  Midtown Mobile, Downtown Mobile, Prichard, Daphne, Saraland, Bay
  Minette, Chickasaw, Satsuma, Spanish Fort, Creola, Stapleton,
  Semmes, Tanner Williams, I65 And I165, Mobile Regional Airport,
  Wilmer and I65 And AL 158.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

&&

LAT...LON 3073 8841 3088 8842 3092 8841 3088 8775
      3055 8783
TIME...MOT...LOC 0840Z 283DEG 39KT 3082 8832 

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

1 follow-up statement

857 
WWUS54 KMOB 070900
SVSMOB

Severe Weather Statement
National Weather Service Mobile AL
400 AM CDT SAT APR 7 2018

ALC003-097-070909-
/O.CAN.KMOB.SV.W.0009.000000T0000Z-180407T0930Z/
Mobile AL-Baldwin AL-
400 AM CDT SAT APR 7 2018

...THE SEVERE THUNDERSTORM WARNING FOR CENTRAL MOBILE AND WEST
CENTRAL BALDWIN COUNTIES IS CANCELLED...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore the warning has been cancelled.

LAT...LON 3073 8841 3088 8842 3092 8841 3088 8775
      3055 8783
TIME...MOT...LOC 0857Z 283DEG 39KT 3077 8808 

$$

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 6, 10:06 PM CDT	Special Weather Statement	MOB	Choctaw	39 min
Apr 6, 11:30 PM CDT	Areal Flood Advisory	MOB	Choctaw	3 hr
Apr 7, 1:06 AM CDT	Flash Flood Warning	MOB	Choctaw	4 hr
Apr 7, 1:14 AM CDT	Special Weather Statement	MOB	Clarke	46 min
Apr 7, 2:44 AM CDT	Special Weather Statement	MOB	Butler, Crenshaw	61 min
Apr 7, 3:24 AM CDT	Special Weather Statement	MOB	Mobile	51 min
Apr 7, 3:45 AM CDT	Special Marine Warning	MOB		45 min
Apr 7, 3:59 AM CDT	Small Craft Advisory	MOB		30 hr
Apr 7, 5:27 AM CDT	Special Marine Warning	MOB		63 min
Apr 7, 6:34 AM CDT	Special Marine Warning	MOB		41 min
Apr 7, 6:55 AM CDT	Special Marine Warning	MOB		65 min
Apr 7, 7:54 AM CDT	Special Marine Warning	MOB		66 min
Apr 7, 8:45 AM CDT	Special Marine Warning	MOB		2 hr
Apr 7, 8:51 AM CDT	Special Marine Warning	MOB		84 min
Apr 7, 9:54 AM CDT	Special Marine Warning	MOB		96 min

Nearby

Severe Thunderstorm Warnings in Alabama, 2018 Every severe thunderstorm warning in 2018

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.