Alert archive / Florida / Severe Thunderstorm Warnings in 1990

Severe Thunderstorm Warning 17, NWS Miami, FL

August 23, 1990Miami-Dade County, Florida

NWS Miami, FL issued this severe thunderstorm warning at Aug 23, 1990, 4:27 PM EDT for Miami-Dade County, Florida. It was in force for 63 min.

The area

The counties it named.

The facts

Issued: Aug 23, 1990, 4:27 PM EDT (20:27 UTC)
Expired: Aug 23, 1990, 5:30 PM EDT
In force: 63 min
Issued by: NWS Miami, FL
Area: Whole counties

County Miami-Dade 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

Key West, FL (KEYW), launched 12:00Z, 8.5 hours before the alert went out and 169 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 2432 J/kg
Mixed-layer CIN: -15 J/kg
Mixed-layer LCL: 900 m above ground
0-6 km bulk shear: 12 kt
0-1 km storm-relative helicity: 3 m²/s²
0-3 km storm-relative helicity: 44 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 KMIA 232030
SVRMIA
FLC025-232130-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM AND SPECIAL MARINE WARNING
NATIONAL WEATHER SERVICE MIAMI FL
427 PM EDT THU AUG 23 1990
 
THE NATIONAL WEATHER SERVICE IN MIAMI HAS ISSUED A
SEVERE THUNDERSTORM AND SPECIAL MARINE WARNING
EFFECTIVE UNTIL  530 PM EDT
FOR PEOPLE IN THE FOLLOWING LOCATIONS...
 
IN SOUTHEAST FLORIDA
 
   ...EASTERN DADE COUNTY
 
  AND FOR BOATERS ON THE COASTAL WATERS FROM
 
   ...KEY LARGO  TO  HALLANDALE
 
AT 425 PM RADAR INDICATED SEVERE THUNDERSTORMS OVER MUCH OF EASTERN
DADE COUNTY AND THIS WAS CONFIRMED BY THE REPORT OF HAIL AT TAMIAMI
AIRPORT. THE STORMS ARE MOVING TO THE NORTHEAST AT 10 MPH AND WILL
MOVE INTO THE COASTAL WATERS DURING THE NEXT HOUR.
 
DAMAGING WIND...LARGE HAIL...VERY HEAVY RAIN...AND DEADLY LIGHTNING
ARE ALL POSSIBLE IN A SEVE
RE THUNDERSTORM. SEEK SHELTER IN A STRONG
BUILDING. STAY AWAY FROM WINDOWS. DO NOT USE TELEPHONES OR
ELECTRICAL APPLIANCES. A MOBILE HOME IS NOT A SAFE REFUGE FROM A
SEVERE THUNDERSTORM...MOVE TO A MORE SUBSTANTIAL BUILDING.
 
THUNDERSTORMS THREATEN BOATER SAFETY WITH GUSTY WINDS OF 35 KNOTS
OR GREATER...ROUGH SEAS AND LIGHTNING.  YOUR BEST COURSE OF ACTION
IS TO SEEK SAFE HARBOR...BUT IF YOU ARE CAUGHT ON THE OPEN WATER...
STAY BELOW DECK AND AWAY FROM UNGROUNDED METAL OBJECTS. MAKE SURE
YOU AND ALL YOUR CREW ARE WEARING FLOTATION DEVICES.
 
IF THREATENING WEATHER IS SIGHTED...TAKE SHELTER...THEN ASK 'A LAW
ENFORCEMENT AGENCY TO RELAY YOUR SEVERE WEATHER REPORT TO THE LOCAL
NATIONAL WEATHER SERVICE OFFICE.
(ALWAYS SELECT THIS PHRASE AND THEN DELETE THIS LINE FROM WARNING.)

The office that day

Everything else NWS Miami, FL issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 23, 4:11 PM EDT	Severe Thunderstorm Warning	MFL	Miami-Dade	49 min

Nearby

Severe Thunderstorm Warnings in Florida, 1990 Every 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.