Alert archive / Alabama / Flash Flood Warnings in 1998

Flash Flood Warning 60, NWS Birmingham, AL

August 12, 1998Jefferson County, Alabama

NWS Birmingham, AL issued this flash flood warning at Aug 12, 1998, 9:37 AM CDT for Jefferson County, Alabama. It was in force for 2 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Aug 12, 1998, 9:37 AM CDT (14:37 UTC)
Expired
Aug 12, 1998, 12:05 PM CDT
In force
2 hr
Issued by
NWS Birmingham, AL
Area
Whole counties

County Jefferson County, AL

The radar

The Birmingham radar (KBMX), 44 km from the middle of the area, began a volume at 14:39 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

Birmingham, AL (KBMX), launched 12:00Z, 2.6 hours before the alert went out and 43 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 1998-08-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 196 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 1998-08-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 18 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
196 J/kg
Mixed-layer CIN
-113 J/kg
Mixed-layer LCL
1151 m above ground
0-6 km bulk shear
20 kt
0-1 km storm-relative helicity
18 m²/s²
0-3 km storm-relative helicity
49 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.2

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KBHM 121437
FFWBHM
ALC073-121705-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE BIRMINGHAM AL
937 AM CDT WED AUG 12 1998

THE NATIONAL WEATHER SERVICE IN BIRMINGHAM HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  JEFFERSON COUNTY... IN CENTRAL ALABAMA

* UNTIL 1205 PM CDT

* AT 935 AM CDT... NATIONAL WEATHER SERVICE DOPPLER RADAR SHOWED
  THUNDERSTORMS WITH VERY HEAVY RAIN ACROSS MOST OF JEFFERSON COUNTY.
  MOVEMENT WAS SLOWLY TO THE EAST.

* VERY HEAVY RAIN HAS FALLEN OVER MOST OF JEFFERSON COUNTY THIS MORNING
  ...WITH SOME LOCATIONS NEAR AND NORTH OF BIRMINGHAM RECEIVING BETWEEN
  TWO AND THREE INCHES OF RAINFALL.  ADDITION SHOWERS AND THUNDERSTORMS
  WERE DEVELOPING AND WILL ALSO MOVE ACROS THE SAME AREAS OF THE COUNTY
  DURING THE NEXT FEW HOURS.  ADDITIONAL RAINFALL OF ONE OR MORE INCHES
  ARE POSSIBLE...AND FLASH FLOODING IS LIKELY.

DON'T DRIVE INTO AREAS WHERE WATER COVERS THE ROAD!


AREA RESIDENTS SHOULD MONITOR FLOOD CONDITIONS... AND BE PREPARED
TO MOVE TO HIGHER GROUND... SHOULD FLOOD WATERS THREATEN. IF FLASH
FLOODING IS OBSERVED... ACT QUICKLY. MOVE TO HIGHER GROUND TO
ESCAPE FLOOD WATERS. DO NOT STAY IN AREAS SUBJECT TO FLOODING WHEN
WATER BEGINS RISING.

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 12, 9:17 AM CDTFlash Flood WarningBMXWalker2 hr
Aug 12, 3:15 PM CDTFlash Flood WarningBMXDeKalb2 hr

Nearby

Flash Flood Warnings in Alabama, 1998Every flash flood warning in 1998

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.