Alert archive / Alabama / Severe Thunderstorm Warnings in 1990

Severe Thunderstorm Warning 70, NWS Birmingham, AL

May 20, 1990Randolph County, Alabama

NWS Birmingham, AL issued this severe thunderstorm warning at May 20, 1990, 1:07 PM CDT for Randolph County, Alabama. It was in force for 53 min.

The area

The counties it named.

The facts

Issued
May 20, 1990, 1:07 PM CDT (18:07 UTC)
Expired
May 20, 1990, 2:00 PM CDT
In force
53 min
Issued by
NWS Birmingham, AL
Area
Whole counties

County Randolph County, AL

The radar

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

The nearest sounding before it

Centreville/Bibb, AL (KCKL), launched 12:00Z, 6.1 hours before the alert went out and 168 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, Centreville/Bibb, AL at 12:00Z on 1990-05-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 429 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, Centreville/Bibb, AL at 12:00Z on 1990-05-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 92 square meters per square second.193958Sfc1 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
429 J/kg
Mixed-layer CIN
-34 J/kg
Mixed-layer LCL
689 m above ground
0-6 km bulk shear
35 kt
0-1 km storm-relative helicity
92 m²/s²
0-3 km storm-relative helicity
93 m²/s²
Significant tornado parameter
0.2
Supercell composite
1.6

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KBHM 201809
SVRBHM
ALC111-201900-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE BIRMINGHAM AL
107 PM CDT SUN MAY 20 1990
 
THE NATIONAL WEATHER SERVICE IN BIRMINGHAM HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL  200 PM CDT
FOR PEOPLE IN THE FOLLOWING LOCATION...
 
IN NORTH ALABAMA
 
   ...RANDOLPH COUNTY
 
AT 1:10 PM CDT WEATHER SERVICE RADAR SHOWED A LINE OF SEVERE
THUNDERSTORMS ENTERING NORTHWEST RANDOLPH COUNTY. THIS LINE WAS MOVING
TO THE EAST AT 30 MPH. SEVERAL REPORTS OF DAMAGE HAVE ALREADY BEEN
REPORTED WITH THESE STORMS.
 
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

Special weather statement, May 20, 12:04 PM CDT, 1 hour 3 minutes before
ALZ010-011-012-014-201800-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MONTGOMERY AL
NOON CDT SUN MAY 20 1990

SEVERE THUNDERSTORM WATCH IN EFFECT UNTIL 3 PM CDT...FOR PARTS OF
CENTRAL ALABAMA...

WEATHER RADAR AT MONTGOMERY SHOWS A LINE OF STRONG THUNDERSTORMS FROM
NEAR DEMOPOLIS TO NORTHEAST OF BIRMINGHAM ALABAMA. THIS LINE WAS
MOVING SOUTHEAST AT 25 TO 30 MPH.

COOSA...AUTAUGA...AND DALLAS COUNTIES WILL BE AFFECTED BY THIS L>INE
OF THUNDERSTORMS IN ONE TO TWO HOURS.  ALSO STORM DAMAGE HAS OCCURRED
WITH THE NORTHERN PART OF THIS LINE.
Local storm report, May 20, 12:52 PM CDT, 15 minutes before
STORM REPORT
NATIONAL WEATHER SERVICE BIRMINGHAM AL
1251 PM CDT SUN MAY 20 1990

1003 AM...NUMEROUS TREES DOWN AND SEVERAL BUILDINGS DAMAGED IN WESTERN
          LAMAR COUNTY.

1035 AM...HIGH WINDS IN CARBON HILL /WALKER COUNTY/. WIDESPREAD POWER
          OUTAGES...NUMEROUS TREES DOWN AND MOBILE HOME DAMAGED.
          SEVERE THUNDERSTORM WATCH AND WARNING IN EFFECT FOR WALKER
          COUNTY.

1140 AM...WIND GUSTS 30-40 MPH ON I465 JUST WEST OF BIRMINGHAM. SEVERE
          THUNDERSTORM WARNING FOR JEFFERSON COUNTY IN EFFECT.

1142 AM...POWER LINES DOWN...CARS DAMAGED AND PEA SIZED HAIL AT CIVIC
          CENTER IN DOWNTOWN BIRMINGHAM.

1148 AM...POWER OUTAGES AT THE BIRMINGHAM AIRPORT VINICITY.

1150 AM...58 MPH WIND GUST AND POWER OUTAGE IN ARGO /ST. CLAIR COUNTY/
          SEVERE THUNDERSTORM WARNING IN EFFECT FOR ST. CLAIR COUNTY.

1218 PM...56 MPH WIND GUST IN GADSDEN /ETOWAH COUNTY/ REPORTED BY
          HAM OPERATORS ANDw EMA DIRECTOR. SEVERE THUNDERSTORM WARNING
          IN EFFECT FOR ETOWAH COUNTY.

The office that day

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

IssuedProductOfficeCountiesLasted
May 20, 1:22 AM CDTFlash Flood WarningBMXMarion2 hr
May 20, 10:06 AM CDTSevere Thunderstorm WarningBMXFayette, Lamar69 min
May 20, 10:36 AM CDTSevere Thunderstorm WarningBMXWalker54 min
May 20, 11:03 AM CDTSevere Thunderstorm WarningBMXBlount, Cullman57 min
May 20, 11:08 AM CDTSevere Thunderstorm WarningBMXJefferson67 min
May 20, 11:12 AM CDTSevere Thunderstorm WarningBMXTuscaloosa48 min
May 20, 11:47 AM CDTSevere Thunderstorm WarningBMXSt. Clair, Shelby43 min
May 20, 11:47 AM CDTSevere Thunderstorm WarningBMXEtowah43 min
May 20, 11:55 AM CDTSevere Thunderstorm WarningBMXMarshall35 min
May 20, 12:15 PM CDTSevere Thunderstorm WarningBMXChilton45 min
May 20, 12:28 PM CDTSevere Thunderstorm WarningBMXCalhoun, Talladega62 min
May 20, 12:28 PM CDTSevere Thunderstorm WarningBMXCherokee, Etowah62 min
May 20, 12:45 PM CDTSevere Thunderstorm WarningBMXClay, Cleburne60 min
May 20, 3:29 PM CDTSevere Thunderstorm WarningBMXPickens, Tuscaloosa46 min
May 20, 4:07 PM CDTTornado WarningBMXTuscaloosa53 min
May 20, 4:57 PM CDTSevere Thunderstorm WarningBMXTuscaloosa63 min
May 20, 6:05 PM CDTSevere Thunderstorm WarningBMXBibb55 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; the sounding from the Mesonet's radiosonde archive.