Alert archive / Florida / Flash Flood Warnings in 1989

Flash Flood Warning 1, NWS Tallahassee, FL

May 20, 1989Okaloosa County, Santa Rosa County, Florida

NWS Tallahassee, FL issued this flash flood warning at May 20, 1989, 12:35 PM CDT for Okaloosa County, Santa Rosa County, Florida. It was in force for 3 hr.

The area

The counties it named.

The facts

Issued
May 20, 1989, 12:35 PM CDT (17:35 UTC)
Expired
May 20, 1989, 3:30 PM CDT
In force
3 hr
Issued by
NWS Tallahassee, FL
Area
Whole counties

Counties Okaloosa County, FL, Santa Rosa County, FL

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

Apalachicola Mun, FL (KAQQ), launched 12:00Z, 5.6 hours before the alert went out and 203 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, Apalachicola Mun, FL at 12:00Z on 1989-05-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 490 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, Apalachicola Mun, FL at 12:00Z on 1989-05-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 48 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
490 J/kg
Mixed-layer CIN
-130 J/kg
Mixed-layer LCL
952 m above ground
0-6 km bulk shear
16 kt
0-1 km storm-relative helicity
48 m²/s²
0-3 km storm-relative helicity
108 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 KPNS 201737
FFWPNS
FLC091-113-202030-
 
BULLETIN - EBS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE PENSACOLA FL
1235 PM CDT SAT MAY 20 1989
 
THE NATIONAL WEATHER SERVICE IN PENSACOLA HAS ISSUED A
FLASH FLOOD WARNING EFFECTIVE UNTIL  330 PM CDT
FOR PEOPLE IN THE FOLLOWING COUNTIES...
 
IN NORTHWEST FLORIDA
          ...OKALOOSA...SANTA ROSA
 
VERY LARGE THUNDERSTORMS WITH VERY HEAVY RAINFALL RATES HAVE PERSISTED
OVER PORTIONS OF THE WESTERN FLORIDA PANHANDLE DURING THE LAST COUPLE
OF HOURS. ESPECIALLY INVOLVED ARE SANTA ROSA AND OKALOOSA COUNTIES
WHERE RAINFALL RATES OVER SOME AREAS HAS BEEN TWO TO THREE INCHES PER
HOUR.
 
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.
 
A FLASH FLOOD WARNING MEANS THAT FLOODING IS IMMINENT.  IT'S
IMPORTANT( TO KNOW WHERE YOU ARE RELATIVE TO STREAMS...RIVERS...OR
CREEKS WHICH CAN BECOME KILLERS IN HEAVY RAINS.  CAMPERS SHOULD
AVOID CAMPING ALONG STREAMS OR CREEKS DURING THREATENING RAINS.

Nearby

Flash Flood Warnings in Florida, 1989Every flash flood warning in 1989

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.