Alert archive / Florida / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 137, NWS Miami, FL

August 20, 1997Broward County, Florida

NWS Miami, FL issued this severe thunderstorm warning at Aug 20, 1997, 4:19 PM EDT for Broward County, Florida. It was in force for 41 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: Aug 20, 1997, 4:19 PM EDT (20:19 UTC)
Expired: Aug 20, 1997, 5:00 PM EDT
In force: 41 min
Issued by: NWS Miami, FL
Area: Whole counties

County Broward County, FL

The radar

The Miami radar (KAMX), 60 km from the middle of the area, began a volume at 20:19 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, 8.3 hours before the alert went out and 40 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: 2545 J/kg
Mixed-layer CIN: -2 J/kg
Mixed-layer LCL: 739 m above ground
0-6 km bulk shear: 16 kt
0-1 km storm-relative helicity: 2 m²/s²
0-3 km storm-relative helicity: 13 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 202020 RRA
SVRMIA
FLC011-202100-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM AND SPECIAL MARINE WARNING
NATIONAL WEATHER SERVICE MIAMI FL
419 PM EDT WED AUG 20 1997
 
THE NATIONAL WEATHER SERVICE IN MIAMI HAS ISSUED A
SEVERE THUNDERSTORM AND SPECIAL MARINE WARNING
EFFECTIVE UNTIL  500 PM EDT
FOR PEOPLE IN THE FOLLOWING LOCATION......
 
IN SOUTHEAST FLORIDA
 
   ...EASTERN BROWARD COUNTY
 
AND THE ADJACENT COASTAL WATERS
 
AT 420 PM...MIAMI DOPPLER RADAR INDICATED SEVERE THUNDERSTORMS OVER
THE EASTERN PORTION OF BROWARD COUNTY FROM MIRAMAR AND PEMBROKE
PINES TO NEAR DEERFIELD BEACH. THESE STORMS ARE MOVING SLOWLY TO THE
EAST AND WILL BEGIN TO MOVE OUT OVER THE COASTAL WATERS OF BROWARD
COUNTY BY 440 PM.
 
DAMAGING WIND IN EXCESS OF 55 MPH...LARGE HAIL...VERY HEAVY RAIN...
AND DEADLY LIGHTNING ARE ALL POSSIBLE IN A SEVERE THUNDERSTORM. SEEK
SHELTER IN A STRONG BUILDING. STAY AWAY FROM WINDOWS. DO NOT USE
TELEPHONES OR ELECTRICAL APPLIANCES.
 
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 AR LOW PROFILE AND KEEP AWAY FROM
UNGROUNDED METAL OBJECTS. WEAR FLOTATION DEVICES.

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 20, 4:00 PM EDT	Severe Thunderstorm Warning	MFL	Broward	45 min
Aug 20, 5:12 PM EDT	Severe Thunderstorm Warning	MFL	Collier, Hendry	48 min

Nearby

Severe Thunderstorm Warnings in Florida, 1997 Every severe thunderstorm warning in 1997

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.