Alert archive / Alabama / Severe Thunderstorm Warnings in 1990

Severe Thunderstorm Warning 161, NWS Mobile, AL

August 20, 1990Mobile County, Alabama

NWS Mobile, AL issued this severe thunderstorm warning at Aug 20, 1990, 9:06 PM CDT for Mobile County, Alabama. It was in force for 54 min. 1 report came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued
Aug 20, 1990, 9:06 PM CDT (02:06 UTC)
Expired
Aug 20, 1990, 10:00 PM CDT
In force
54 min
Issued by
NWS Mobile, AL
Area
Whole counties

County Mobile County, AL

The radar

The WSR-88D network and its archive begin in 1991, so there is no radar volume for this alert.

What was reported inside it

TimeReportWhereRemark
Aug 20, 9:25 PM CDTThunderstorm Wind 0Mobile, AL

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in. Storm Data before 1996 records only tornadoes, thunderstorm wind and hail.

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 00:00Z, 2.1 hours before the alert went out and 152 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, Slidell Radar S, LA at 00:00Z on 1990-08-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2307 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, Slidell Radar S, LA at 00:00Z on 1990-08-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 44 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
2307 J/kg
Mixed-layer CIN
-39 J/kg
Mixed-layer LCL
1244 m above ground
0-6 km bulk shear
10 kt
0-1 km storm-relative helicity
44 m²/s²
0-3 km storm-relative helicity
64 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KMOB 210208
SVRMOB
ALC097-210300-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOBILE AL
906 PM CDT MON AUG 20 1990
 
THE NATIONAL WEATHER SERVICE IN MOBILE HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL 1000 PM CDT
FOR PEOPLE IN THE FOLLOWING LOCATIONS...
 
IN SOUTHWEST ALABAMA
 
   ...SOUTHERN MOBILE COUNTY
 
AT 905 PM CDT MOBILE RADAR INDICATED A SEVERE THUNDERSTORM IN
SOUTHEAST MOBILE COUNTY ALABAMA JUST NORTH OF ALABAMA PORT. IT
WAS MOVING WEST TOWARD BAYOU LA BATRE AT 15 MILES AN HOUR.
 
THIS STORM CAUSED WIND DAMAGE AND HAIL ACROSS SOUTHERN BALDWIN
COUNTY DURING THE PAST HOUR.
 
SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 55
MPH...DESTRUCTIVE HAIL...DEADLY LIGHTNING...AND VERY HEAVY RAIN.
FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR
OF YOUR HOME OR BUSINESS.  HEAVY RAINS FLOOD ROADS QUICKLY SO
DON'T DRIVE INTO AREAS WHERE WATER COVERS THE ROAD.

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

In the hours before

Local storm report, Aug 20, 8:21 PM CDT, 45 minutes before
STORM REPORT
NATIONAL WEATHER SERVICE MOBILE AL
820 PM CDT MON AUG 20 1990

...ATTN SELS...
TIME OF REPORT    REPORT
800 PM CDT        HAM OPERATOR REPORTED HAIL (NO SIZE) IN SEMINOLE
                  (BALDWIN COUNTY) ALABAMA.
807 PM CDT        MOBILE STATE POLICE REPORTED A TROOPER IN SUMMERDALE/
                  FOLEY (BALDWIN COUNTY) ALABAMA HAD VERY STRONG WINDS
                  HAIL AND HEAVY RAIN-UNABLE TO SEE ANYTHING.
810 PM CDT        ROBERTSDALE POLICE REPORTED CHIEF OF POLICE SUMMERDALE
                  (BALDWIN COUNTY) ALABAMA ROOFS OFF BUILDINGS IN
                  SUMMERDALE.

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 20, 7:37 PM CDTSevere Thunderstorm WarningMOBBaldwin68 min

Nearby

Severe Thunderstorm Warnings in Alabama, 1990Every severe thunderstorm warning in 1990

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive.