Alert archive / Florida / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 66, NWS Miami, FL

July 4, 1998Miami-Dade County, Florida

NWS Miami, FL issued this severe thunderstorm warning at Jul 4, 1998, 3:18 PM EDT for Miami-Dade County, Florida. It was in force for 57 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
Jul 4, 1998, 3:18 PM EDT (19:18 UTC)
Expired
Jul 4, 1998, 4:15 PM EDT
In force
57 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 19:21 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 12:00Z, 7.3 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 12:00Z on 1998-07-04Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1054 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 12:00Z on 1998-07-04The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 21 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
1054 J/kg
Mixed-layer CIN
-50 J/kg
Mixed-layer LCL
1476 m above ground
0-6 km bulk shear
8 kt
0-1 km storm-relative helicity
21 m²/s²
0-3 km storm-relative helicity
56 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.

076 
WUUS1 KMIA 041920 RRA
SVRMIA
FLC025-042015-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MIAMI FL
318 PM EDT SAT JUL 4 1998

THE NATIONAL WEATHER SERVICE IN MIAMI HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  EASTERN DADE COUNTY IN SOUTHEASTERN FLORIDA

* UNTIL 415 PM EDT

* MIAMI DOPPLER RADAR HAS DETECTED A SEVERE THUNDERSTORM
 SOUTH OF WEST CHESTER IN WEST CENTRAL DADE COUNTY. THE
 STORM WAS MOVING SOUTH AT 15 MPH. FREQUENT LIGHTNING...
 HEAVY RAIN...STRONG WIND GUSTS...AND HAIL ARE POSSIBLE WITH THIS
 STORM.

* SOME LOCATIONS AFFECTED WILL BE KENDALL...RICHMOND HEIGHTS...
 PERRINE...CUTLER RIDGE...SAGA BAY...AND GOULDS WITHIN THE
 NEXT HOUR.


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.

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

In the hours before

Special weather statement, Jul 4, 9:55 AM EDT, 5 hours 23 minutes before
AMZ610-630-631-650>654-656-670>676-FLZ063-066>078-042200-

SOUTH FLORIDA HAZARDOUS WEATHER OUTLOOK...UPDATE...
NATIONAL WEATHER SERVICE MIAMI FL
955 AM EDT SAT JUL 04 1998

...WIDELY SCATTERED SHOWERS AND THUNDERSTORMS ACROSS SOUTH
   FLORIDA TODAY MAINLY INLAND AND WEST WITH POSSIBLE HAIL...
...HAZY SMOKEY SKIES ACROSS THE SOUTH FLORIDA TODAY...
...HEAT INDICES ABOVE 105 THIS AFTERNOON OVER SOUTH FLORIDA...

WIDELY SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED ACROSS SOUTH
FLORIDA TODAY MAINLY OVER THE INLAND AND WEST PORTIONS. SOME OF THESE
THUNDERSTORMS...WHICH WILL DEVELOP DURING THE LATE AFTERNOON HOURS
ALONG THE SEABREEZE FRONT...MAY PRODUCE LOCALLY HEAVY RAINFALL EXCEEDING
ONE INCH ALONG WITH GUSTY WINDS AND POSSIBLE HAIL.

SMOKE FROM THE FIRES IN EAST CENTRAL FLORIDA IS NOW OVER THE BAHAMAS
...THE FLORIDA STRAITS...ANDS SOUTH FLORIDA. VISIBILITIES HAVE BEEN
REPORTED TO BE AS LOW AS 1 MILE AT FREEPORT IN THE BAHAMAS AND EVEN
IN HAVANA CUBA. AREAS ON THE PENINSULA NEAR LAKE OKEECHOBEE INCLUDING
WEST PALM BEACH HAS HAD VISIBILITIES LOWERED TO LESS THAN 3 MILES.

CURRENTLY THE MOST DENSE SMOKE IS OVER THE ATLANTIC BUT SHIFTING
UPPER LEVEL WINDS COMBINED WITH THE AFTERNOON SEA BREEZE WILL BRING
LOWER VISIBILITY OVER THE REMAINDER OF SOUTH FLORIDA AND INTO THE KEYS.

TEMPERATURES WILL CLIMB INTO THE MID AND UPPER 90S ACROSS SOUTH
FLORIDA THIS AFTERNOON. HUMIDITIES AROUND 50 PERCENT WILL PRODUCE
HEAT INDICES BETWEEN 105 AND 110 DEGREES OVER INTERIOR SECTIONS.
Special weather statement, Jul 4, 9:55 AM EDT, 5 hours 23 minutes before
AMZ610-630-631-650>654-656-670>676-FLZ063-066>078-042200-

SOUTH FLORIDA HAZARDOUS WEATHER OUTLOOK...UPDATE...
NATIONAL WEATHER SERVICE MIAMI FL
955 AM EDT SAT JUL 04 1998

...WIDELY SCATTERED SHOWERS AND THUNDERSTORMS ACROSS SOUTH
   FLORIDA TODAY MAINLY INLAND AND WEST WITH POSSIBLE HAIL...
...HAZY SMOKEY SKIES ACROSS THE SOUTH FLORIDA TODAY...
...HEAT INDICES ABOVE 105 THIS AFTERNOON OVER SOUTH FLORIDA...

WIDELY SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED ACROSS SOUTH
FLORIDA TODAY MAINLY OVER THE INLAND AND WEST PORTIONS. SOME OF THESE
THUNDERSTORMS...WHICH WILL DEVELOP DURING THE LATE AFTERNOON HOURS
ALONG THE SEABREEZE FRONT...MAY PRODUCE LOCALLY HEAVY RAINFALL EXCEEDING
ONE INCH ALONG WITH GUSTY WINDS AND POSSIBLE HAIL.

SMOKE FROM THE FIRES IN EAST CENTRAL FLORIDA IS NOW OVER THE BAHAMAS
...THE FLORIDA STRAITS...ANDS SOUTH FLORIDA. VISIBILITIES HAVE BEEN
REPORTED TO BE AS LOW AS 1 MILE AT FREEPORT IN THE BAHAMAS AND EVEN
IN HAVANA CUBA. AREAS ON THE PENINSULA NEAR LAKE OKEECHOBEE INCLUDING
WEST PALM BEACH HAS HAD VISIBILITIES LOWERED TO LESS THAN 3 MILES.

CURRENTLY THE MOST DENSE SMOKE IS OVER THE ATLANTIC BUT SHIFTING
UPPER LEVEL WINDS COMBINED WITH THE AFTERNOON SEA BREEZE WILL BRING
LOWER VISIBILITY OVER THE REMAINDER OF SOUTH FLORIDA AND INTO THE KEYS.

TEMPERATURES WILL CLIMB INTO THE MID AND UPPER 90S ACROSS SOUTH
FLORIDA THIS AFTERNOON. HUMIDITIES AROUND 50 PERCENT WILL PRODUCE
HEAT INDICES BETWEEN 105 AND 110 DEGREES OVER INTERIOR SECTIONS.

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 4, 3:00 PM EDTSevere Thunderstorm WarningMFLCollier65 min
Jul 4, 4:58 PM EDTSevere Thunderstorm WarningMFLMonroe47 min
Jul 4, 6:18 PM EDTSevere Thunderstorm WarningMFLMiami-Dade47 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.