Alert archive / Georgia / Flash Flood Warnings in 1990

Flash Flood Warning 62, NWS Atlanta, GA

August 23, 1990Gwinnett County, Georgia

NWS Atlanta, GA issued this flash flood warning at Aug 23, 1990, 12:07 AM EDT for Gwinnett County, Georgia. It was in force for 2 hr.

The area

The counties it named.

The facts

Issued
Aug 23, 1990, 12:07 AM EDT (04:07 UTC)
Expired
Aug 23, 1990, 2:15 AM EDT
In force
2 hr
Issued by
NWS Atlanta, GA
Area
Whole counties

County Gwinnett County, GA

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

Athens Municipal, GA (KAHN), launched 00:00Z, 4.1 hours before the alert went out and 67 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, Athens Municipal, GA at 00:00Z on 1990-08-23Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2441 joules per kilogram.LCLEL10008507005003002001001 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, Athens Municipal, GA at 00:00Z on 1990-08-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 81 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
2441 J/kg
Mixed-layer CIN
0 J/kg
Mixed-layer LCL
702 m above ground
0-6 km bulk shear
24 kt
0-1 km storm-relative helicity
81 m²/s²
0-3 km storm-relative helicity
136 m²/s²
Significant tornado parameter
1.1
Supercell composite
6.6

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KATL 230410
FFWATL
GAC135-230615-
 
BULLETIN - EBS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE ATLANTA  GA
1207 AM EDT THU AUG 23 1990
 
THE NATIONAL WEATHER SERVICE IN ATLANTA  HAS ISSUED A
FLASH FLOOD WARNING EFFECTIVE UNTIL  215 AM EDT
FOR PEOPLE IN THE FOLLOWING LOCATIONS...
 
IN NORTHWEST GEORGIA
 
   ...GWINNETT COUNTY
 
AT 1205 AM EDT THUNDERSTORMS CONTINUED TO BRING LOCALLY
TORRENTIAL RAINS TO PORTIONS OF GWINNETT COUNTY. NORCROSS
POLICE REPORTED MITCHELL ROAD IMPASSABLE AND CARS WERE
CAUGHT IN THE FLOOD WATERS. BEAVER RUIN ROAD WAS ALSO
FLOODED. OTHER ROADS IN NORCROSS AND IN OTHER PARTS OF
THE COUNTY MAY BE COMPLETELY UNDER WATER.
 
CREEKS AND STREAMS MAY SOON BE WELL OUT OF THEIR BANKS
IF RAIN DOES NOT DIMINISH.
 
 
 
DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE
ROADWAY.  THE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO
CROSS SAFELY.  VEHICLES CAUGHT IN RISING WATER SHOULD BE
ABANDONED QUICKLY.  MOVE TO HIGHER GROUND.
 
MOST DEATHS IN FLASH FLOODING OCCUR IN AUTOMOBILES.  DO NOT
ATTEMPT TO CROSS BRIDGES...DIPS...OR LOW SPOTS IF WATER COVERS
THE ROADWAY.  NEVER TRY TO CROSS A FLOWING STREAM...EVEN A
SMALL ONE...ON FOOT.

The office that day

Everything else NWS Atlanta, GA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 22, 8:11 PM EDTSevere Thunderstorm WarningFFCBarrow, Walton64 min
Aug 23, 4:24 PM EDTSevere Thunderstorm WarningFFCLaurens66 min
Aug 23, 7:57 PM EDTSevere Thunderstorm WarningFFCHouston63 min

Nearby

Flash Flood Warnings in Georgia, 1990Every flash flood 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.