Alert archive / Florida / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 34, NWS Miami, FL

March 20, 1998Miami-Dade County, Florida

NWS Miami, FL issued this severe thunderstorm warning at Mar 20, 1998, 12:49 AM EST for Miami-Dade County, Florida. It was in force for 61 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Mar 20, 1998, 12:49 AM EST (05:49 UTC)
Expired
Mar 20, 1998, 1:50 AM EST
In force
61 min
Issued by
NWS Miami, FL
Area
Whole counties

County Miami-Dade County, FL

The radar

The Miami radar (KAMX), 9 km from the middle of the area, began a volume at 05:52 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

Miami, FL (KMFL), launched 00:00Z, 5.8 hours before the alert went out and 31 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, Miami, FL at 00:00Z on 1998-03-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 345 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, Miami, FL at 00:00Z on 1998-03-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 65 square meters per square second.193958Sfc1 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
345 J/kg
Mixed-layer CIN
-107 J/kg
Mixed-layer LCL
1008 m above ground
0-6 km bulk shear
55 kt
0-1 km storm-relative helicity
65 m²/s²
0-3 km storm-relative helicity
156 m²/s²
Significant tornado parameter
0.1
Supercell composite
3.6

Open this sounding in Storm Lab

The text

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

070 
WUUS1 KMIA 200553 RRA
SVRMIA
AMZ630-651-671-FLC025-200650-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MIAMI FL
1249 AM EST FRI MAR 20 1998

THE NATIONAL WEATHER SERVICE IN MIAMI FL HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL 150 AM EST
FOR PEOPLE IN THE FOLLOWING LOCATIONS...

IN SOUTHEASTERN FLORIDA

   ...DADE COUNTY INCLUDING ADJACENT COASTAL WATERS

AT 1248 AM EST... DOPPLER RADAR INDICATED A LINE OF SEVERE
THUNDERSTORMS FROM NORTHEAST DADE COUNTY SOUTHWEST TOWARDS
THE EVERGLADES. THE LINE OF THUNDERSTORMS IS MOVING SOUTHEAST
AT 20 TO 25 MPH. THE STORMS WILL AFFECT MOST OF EASTERN DADE
COUNTY FROM OPA-LOCKA SOUTH THROUGH MIAMI...CORAL GABLES...
KENDALL AND CUTLER RIDGE.

SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 55 MPH...
LARGE HAIL...DEADLY LIGHTNING...AND VERY HEAVY RAIN. SEEK SHELTER
IN A STRONG BUILDING. STAY AWAY FROM WINDOWS. DO NOT USE TELEPHONES
OR ELECTRICAL APPLIANCES.

The office that day

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

IssuedProductOfficeCountiesLasted
Mar 19, 10:39 PM ESTSevere Thunderstorm WarningMFLCollier61 min
Mar 19, 11:53 PM ESTSevere Thunderstorm WarningMFLBroward62 min
Mar 20, 12:25 AM ESTSevere Thunderstorm WarningMFLMiami-Dade60 min
Mar 20, 6:07 PM ESTSevere Thunderstorm WarningMFLMonroe78 min

Nearby

Severe Thunderstorm Warnings in Florida, 1998Every severe thunderstorm 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.