Alert archive / Florida / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 71, NWS Miami, FL

July 12, 1998Monroe County, Florida

NWS Miami, FL issued this severe thunderstorm warning at Jul 12, 1998, 7:30 AM EDT for Monroe County, Florida. It was in force for 45 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 12, 1998, 7:30 AM EDT (11:30 UTC)
Expired
Jul 12, 1998, 8:15 AM EDT
In force
45 min
Issued by
NWS Miami, FL
Area
Whole counties

County Monroe County, FL

The radar

The Miami radar (KAMX), 51 km from the middle of the area, began a volume at 11:33 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, 11.5 hours before the alert went out and 69 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 1998-07-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1721 joules per kilogram.LCLEL10008507005003002001001 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 1998-07-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -33 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
1721 J/kg
Mixed-layer CIN
-2 J/kg
Mixed-layer LCL
710 m above ground
0-6 km bulk shear
5 kt
0-1 km storm-relative helicity
-33 m²/s²
0-3 km storm-relative helicity
20 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.

623 
WUUS1 KMIA 121129 RRA
SVRMIA
FLC087-121215-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MIAMI FL
730 AM EDT SUN JUL 12 1998

THE NATIONAL WEATHER SERVICE IN MIAMI HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  MONROE LOWER KEYS IN SOUTHERN FLORIDA

* UNTIL 815 AM EDT

* AT 725 AM DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM OVER THE
  GULF OF MEXICO WATERS 5 TO 10 MILES NORTH OF THE LOWER KEYS. THE
  STORM IS MOVING SOUTHEAST AT 10 TO 15 MPH. STRONG WIND GUSTS IN
  EXCESS OF 60 MPH ARE LIKELY WITH THIS STORM.

* THIS STORM WILL AFFECT THE LOWER KEYS FROM BOCA CHICA TO BIG
  PINE KEY THROUGH 8 AM.

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.

WHEN THUNDERSTORMS ARE OCCURRING...MOVE INSIDE A STRONG BUILDING.
DO NOT STAND BY WINDOWS. DO NOT USE TELEPHONES OR ELECTRICAL
APPLIANCES UNLESS IN AN EMERGENCY UNTIL THE STORM HAS PASSED.
MOTORISTS SHOULD NOT DRIVE INTO LOW WATER CROSSINGS.

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.