Alert archive / Alabama / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 466, NWS Birmingham, AL

August 18, 1997Shelby County, Alabama

NWS Birmingham, AL issued this severe thunderstorm warning at Aug 18, 1997, 5:31 PM CDT for Shelby County, Alabama. It was in force for 49 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 18, 1997, 5:31 PM CDT (22:31 UTC)
Expired
Aug 18, 1997, 6:20 PM CDT
In force
49 min
Issued by
NWS Birmingham, AL
Area
Whole counties

County Shelby County, AL

The radar

The Birmingham radar (KBMX), 14 km from the middle of the area, began a volume at 22:35 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

TimeReportWhereRemark
Aug 18, 5:45 PM CDTThunderstorm Wind 50Alabaster, ALNumerous trees and power lines were down across the city of Alabaster.

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.

The nearest sounding before it

Birmingham, AL (KBMX), launched 12:00Z, 10.5 hours before the alert went out and 14 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 1997-08-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1126 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, Birmingham, AL at 12:00Z on 1997-08-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -1 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
1126 J/kg
Mixed-layer CIN
-57 J/kg
Mixed-layer LCL
903 m above ground
0-6 km bulk shear
11 kt
0-1 km storm-relative helicity
-1 m²/s²
0-3 km storm-relative helicity
-2 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 KBHM 182231 RRA
SVRBHM
ALC117-182320-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE BIRMINGHAM AL
531 PM CDT MON AUG 18 1997

THE NATIONAL WEATHER SERVICE IN BIRMINGHAM AL HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL 620 PM CDT
FOR PEOPLE IN THE FOLLOWING LOCATION...

IN CENTRAL ALABAMA

   ...SHELBY COUNTY
 
AT 530 PM CDT...WEATHER RADAR SHOWED A SEVERE THUNDERSTORM
OVER SHELBY COUNTY NEAR ALABASTER.  THIS STORM WAS MOVING SOUTHEAST AT
25 MPH.
 
IF YOU ARE CAUGHT OUTSIDE... SEEK REFUGE FROM THE STORM IN A
STRONG BUILDING. BOATERS ON AREA LAKES SHOULD TAKE SHELTER.
DAMAGING WIND... LARGE HAIL... VERY HEAVY RAIN... AND DANGEROUS
LIGHTNING ARE ALL L
IKELY. DO NOT SEEK SHELTER UNDER TREES OR OTHER
ISOLATED TALL OBJECTS. THESE ATTRACT LIGHTNING. DO NOT 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, Aug 18, 3:02 PM CDT, 2 hours 29 minutes before
ALZ001>050-GAZ089-090-102-120-190805-

HAZARDOUS WEATHER OUTLOOK...UPDATED
FOR NORTH/CENTRAL AL AND WEST CENTRAL GA
NATIONAL WEATHER SERVICE BIRMINGHAM AL
302 PM CDT MON AUG 18 1997

THUNDERSTORMS WILL CONTINUE FOR THE NEXT SEVERAL HOURS ACROSS
MOST OF ALABAMA AND WEST CENTRAL GEORGIA. THE MOST NUMEROUS STORMS
SHOULD CONTINUE OVER WEST CENTRAL AND CENTRAL ALABAMA THROUGH THE
EARLY EVENING.

THESE STORMS WILL BE SHORT IN DURATION...USUALLY 30 MINUTES BUT HAVE
THE POTENTIAL...AS DO ALL SUMMERTIME STORMS...TO PRODUCE GUSTY WINDS
OF 35 MPH...FREQUENT LIGHTNING...HAIL..AND HEAVY DOWNPOURS OF RAIN.

ISOLATED STORMS MAY BECOME BRIEFLY SEVERE WITH THE GREATEST THREAT
BEING WIND DAMAGE. GIVEN THE ISOLATED EXTENT OF THESE STORMS THE
ACTIVATION OF STORM SPOTTERS AND EMERGENCY MANAGEMENT PERSONNEL
REMAINS UNNECESSARY.
Special weather statement, Aug 18, 3:06 PM CDT, 2 hours 25 minutes before
ALZ001>050-GAZ089-090-102-120-190805-

HAZARDOUS WEATHER OUTLOOK...UPDATED
FOR NORTH/CENTRAL AL AND WEST CENTRAL GA
NATIONAL WEATHER SERVICE BIRMINGHAM AL
302 PM CDT MON AUG 18 1997

THUNDERSTORMS WILL CONTINUE FOR THE NEXT SEVERAL HOURS ACROSS
MOST OF ALABAMA AND WEST CENTRAL GEORGIA. THE MOST NUMEROUS STORMS
SHOULD CONTINUE OVER WEST CENTRAL AND CENTRAL ALABAMA THROUGH THE
EARLY EVENING.

THESE STORMS WILL BE SHORT IN DURATION...USUALLY 30 MINUTES BUT HAVE
THE POTENTIAL...AS DO ALL SUMMERTIME STORMS...TO PRODUCE GUSTY WINDS
OF 35 MPH...FREQUENT LIGHTNING...HAIL..AND HEAVY DOWNPOURS OF RAIN.

ISOLATED STORMS MAY BECOME BRIEFLY SEVERE WITH THE GREATEST THREAT
BEING WIND DAMAGE. GIVEN THE ISOLATED EXTENT OF THESE STORMS THE
ACTIVATION OF STORM SPOTTERS AND EMERGENCY MANAGEMENT PERSONNEL
REMAINS UNNECESSARY.

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 18, 11:39 AM CDTSevere Thunderstorm WarningBMXCleburne61 min
Aug 18, 3:07 PM CDTSevere Thunderstorm WarningBMXElmore, Montgomery33 min
Aug 18, 3:48 PM CDTSevere Thunderstorm WarningBMXMacon32 min
Aug 18, 4:37 PM CDTSevere Thunderstorm WarningBMXMontgomery48 min
Aug 18, 4:45 PM CDTSevere Thunderstorm WarningBMXLowndes45 min
Aug 18, 5:42 PM CDTSevere Thunderstorm WarningBMXChilton48 min
Aug 18, 6:11 PM CDTSevere Thunderstorm WarningBMXDallas34 min

Nearby

Severe Thunderstorm Warnings in Alabama, 1997Every severe thunderstorm warning in 1997

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; radar from the NEXRAD Level II archive.