Alert archive / Florida / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 39, NWS Miami, FL

May 5, 1998Palm Beach County, Florida

NWS Miami, FL issued this severe thunderstorm warning at May 5, 1998, 3:57 PM EDT for Palm Beach County, Florida. It was in force for 68 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
May 5, 1998, 3:57 PM EDT (19:57 UTC)
Expired
May 5, 1998, 5:05 PM EDT
In force
68 min
Issued by
NWS Miami, FL
Area
Whole counties

County Palm Beach County, FL

The radar

The Miami radar (KAMX), 115 km from the middle of the area, began a volume at 19:58 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
May 5, 11:30 AM EDTSevere Thunderstorm WatchSPC6 hr

The nearest sounding before it

Miami, FL (KMFL), launched 12:00Z, 8.0 hours before the alert went out and 93 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 1998-05-05Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 323 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Miami, FL at 12:00Z on 1998-05-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 43 square meters per square second.19395878Sfc1 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
323 J/kg
Mixed-layer CIN
-210 J/kg
Mixed-layer LCL
1647 m above ground
0-6 km bulk shear
28 kt
0-1 km storm-relative helicity
43 m²/s²
0-3 km storm-relative helicity
104 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.8

Open this sounding in Storm Lab

The text

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

693 
WUUS1 KMIA 051958 RRA
SVRMIA
FLC099-052105-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MIAMI FL
357 PM EDT TUE MAY 5 1998

THE NATIONAL WEATHER SERVICE IN MIAMI HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTHWEST PALM BEACH COUNTY IN SOUTHEASTERN FLORIDA

* UNTIL 505 PM EDT

* AT 350 PM EDT... DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM 29
  MILES NORTHWEST OF TWENTYMILE BEND OR 9 MILES NORTH OF SAND CUT
  MOVING SOUTHEAST AT 20 MPH.

  THIS STORM WILL MOVE ALONG THE EASTERN SHORE OF LAKE OKEECHOBEE
AND INTO NORTHWEST PALM BEACH COUNTY. BOATERS IN LAKE OKEECHOBEE AND
INTERESTS IN WEST PALM BEACH COUNTY SHOULD BE ALERT FOR STRONG
GUSTY WINDS...HEAVY RAINS...AND LARGE HAIL.

* A LOCATION NEAR THE PATH OF THIS STORM IS...
  SAND CUT                       BY ABOUT 400 PM EDT

THUNDERSTORMS THREATEN BOATER SAFETY WITH GUSTY WINDS IN EXCESS OF
35 KNOTS...ROUGH SEAS...AND DEADLY LIGHTNING. YOUR BEST COURSE OF
ACTION IS TO SEEK SAFE HARBOR...BUT IF YOU ARE CAUGHT ON THE OPEN
WATER...STAY BELOW DECK OR KEEP A LOW PROFILE AND KEEP AWAY FROM
UNGROUNDED METAL OBJECTS. ALL SHOULD WEAR FLOTATION DEVICES.

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
May 5, 4:22 PM EDTSevere Thunderstorm WarningMFLBroward, Palm Beach48 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.