Alert archive / Florida / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 58, NWS Miami, FL

August 25, 2021Miami-Dade County, Florida

NWS Miami, FL issued this severe thunderstorm warning at Aug 25, 2021, 6:12 AM EDT for Miami-Dade County, Florida. It was in force for 33 min. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Aug 25, 2021, 6:12 AM EDT (10:12 UTC)
Expired
Aug 25, 2021, 6:45 AM EDT
In force
33 min
Issued by
NWS Miami, FL
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

County Miami-Dade County, FL

The radar

The Miami radar (KAMX), 23 km from the middle of the area, began a volume at 10:11 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.

What was reported inside it

TimeReportWhereRemark
Aug 25, 6:19 AM EDTMARINE TSTM WIND 391 Ne Perrine, FLA WIND GUST OF 39 MPH (34 KT) WAS MEASURED BY THE MESONET STATION XSOM AT SOUTH MIAMI (WHICH IS LESS THAN A MILE FROM BISCAYNE BAY) ASSOCIATED WITH A THUNDERSTORM PUSHING THROUGH THE AREA. STATION ELEVATION: 34 FT.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Miami, FL (KMFL), launched 00:00Z, 10.2 hours before the alert went out and 21 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 2021-08-25Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1083 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 00:00Z on 2021-08-25The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -9 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
1083 J/kg
Mixed-layer CIN
-88 J/kg
Mixed-layer LCL
1343 m above ground
0-6 km bulk shear
19 kt
0-1 km storm-relative helicity
-9 m²/s²
0-3 km storm-relative helicity
-25 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.1

Open this sounding in Storm Lab

The text

As transmitted.

265 
WUUS52 KMFL 251012
SVRMFL
FLC086-251045-
/O.NEW.KMFL.SV.W.0058.210825T1012Z-210825T1045Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Miami FL
612 AM EDT Wed Aug 25 2021

The National Weather Service in Miami has issued a

* Severe Thunderstorm Warning for...
  Eastern Miami-Dade County in southeastern Florida...

* Until 645 AM EDT.

* At 612 AM EDT, a severe thunderstorm was located near Key Biscayne,
  moving west at 30 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

  IMPACT...Expect damage to roofs, siding, and trees.

* Locations impacted include...
  Miami, Miami Beach, Coral Gables, Key Biscayne and South Miami. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

Damaging winds and continuous cloud to ground lightning is occurring 
with this storm. Move indoors immediately. Lightning is one of 
nature's leading killers. Remember, if you can hear thunder, you are 
close enough to be struck by lightning.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 2564 8008 2560 8013 2558 8012 2554 8043
      2581 8045 2578 8005
TIME...MOT...LOC 1012Z 086DEG 24KT 2569 8011 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

RAG
3 follow-up statements
452 
WWUS52 KMFL 251016
SVSMFL

Severe Weather Statement
National Weather Service Miami FL
616 AM EDT Wed Aug 25 2021

FLC086-251045-
/O.CON.KMFL.SV.W.0058.000000T0000Z-210825T1045Z/
Miami-Dade FL-
616 AM EDT Wed Aug 25 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 645 AM EDT
FOR EASTERN MIAMI-DADE COUNTY...

At 615 AM EDT, a severe thunderstorm was located over Key Biscayne,
moving west at 30 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Expect damage to roofs, siding, and trees.

Locations impacted include...
Miami, Miami Beach, Coral Gables, Key Biscayne and South Miami. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of 
a building. Wind gusts of nearly 60 mph have been reported with this 
storm.

Continuous cloud to ground lightning is occurring with this storm.
Move indoors immediately. Lightning is one of nature's leading
killers. Remember, if you can hear thunder, you are close enough to
be struck by lightning.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 2564 8008 2560 8013 2558 8012 2554 8043
      2581 8045 2578 8005
TIME...MOT...LOC 1015Z 086DEG 24KT 2569 8014 

TORNADO...POSSIBLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...OBSERVED
MAX WIND GUST...60 MPH

$$

RAG
127 
WWUS52 KMFL 251033
SVSMFL

Severe Weather Statement
National Weather Service Miami FL
633 AM EDT Wed Aug 25 2021

FLC086-251045-
/O.CON.KMFL.SV.W.0058.000000T0000Z-210825T1045Z/
Miami-Dade FL-
633 AM EDT Wed Aug 25 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 645 AM EDT
FOR EASTERN MIAMI-DADE COUNTY...

At 632 AM EDT, a severe thunderstorm was located over Glenvar
Heights, or over South Miami, moving west at 20 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Expect damage to roofs, siding, and trees.

Locations impacted include...
Miami, Coral Gables, South Miami, Kendall and The Redland. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Wind gusts to almost 60 mph have been reported with this storm. For 
your protection move to an interior room on the lowest floor of a 
building.

Continuous cloud to ground lightning is occurring with this storm.
Move indoors immediately. Lightning is one of nature's leading
killers. Remember, if you can hear thunder, you are close enough to
be struck by lightning.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 2554 8043 2581 8045 2579 8021 2557 8020
TIME...MOT...LOC 1032Z 095DEG 19KT 2569 8031 

TORNADO...POSSIBLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...OBSERVED
MAX WIND GUST...60 MPH

$$

RAG/Hadi
862 
WWUS52 KMFL 251035
SVSMFL

Severe Weather Statement
National Weather Service Miami FL
635 AM EDT Wed Aug 25 2021

FLC086-251045-
/O.EXP.KMFL.SV.W.0058.000000T0000Z-210825T1045Z/
Miami-Dade FL-
635 AM EDT Wed Aug 25 2021

...THE SEVERE THUNDERSTORM WARNING FOR EASTERN MIAMI-DADE COUNTY
WILL EXPIRE AT 645 AM EDT...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning will be allowed to expire.  However gusty
winds and heavy rain are still possible with this thunderstorm.

To report severe weather, contact your nearest law enforcement
agency. They will relay your report to the National Weather Service
Miami. You can also share your report with NWS Miami on
Facebook and Twitter.

LAT...LON 2554 8043 2581 8045 2579 8021 2557 8020
TIME...MOT...LOC 1035Z 086DEG 24KT 2569 8032 

$$

RAG/Hadi

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 25, 3:53 AM EDTSmall Craft AdvisoryMFL25 hr
Aug 25, 5:04 AM EDTSpecial Marine WarningMFL116 min
Aug 25, 5:42 AM EDTSpecial Weather StatementMFLMiami-Dade63 min
Aug 25, 6:08 AM EDTSpecial Weather StatementMFLMiami-Dade37 min
Aug 25, 6:37 AM EDTSpecial Weather StatementMFLMiami-Dade38 min
Aug 25, 8:38 AM EDTSpecial Marine WarningMFL52 min
Aug 25, 9:23 AM EDTSpecial Marine WarningMFL97 min
Aug 25, 10:04 AM EDTSpecial Weather StatementMFLBroward41 min
Aug 25, 10:48 AM EDTSpecial Weather StatementMFLBroward42 min
Aug 25, 10:51 AM EDTSpecial Weather StatementMFLPalm Beach39 min
Aug 25, 11:00 AM EDTSevere Thunderstorm WarningMFLPalm Beach12 min
Aug 25, 11:26 AM EDTSpecial Weather StatementMFLBroward49 min
Aug 25, 11:54 AM EDTSpecial Weather StatementMFLCollier51 min
Aug 25, 12:31 PM EDTSpecial Weather StatementMFLCollier44 min
Aug 25, 12:46 PM EDTSpecial Weather StatementMFLCollier29 min
Aug 25, 12:56 PM EDTSpecial Marine WarningMFL2 hr
Aug 25, 1:12 PM EDTSpecial Weather StatementMFLHendry48 min
Aug 25, 1:17 PM EDTSpecial Weather StatementMFLCollier28 min
Aug 25, 1:37 PM EDTSpecial Weather StatementMFLCollier38 min
Aug 25, 1:46 PM EDTSpecial Marine WarningMFL59 min
Aug 25, 2:40 PM EDTSpecial Marine WarningMFL95 min
Aug 25, 3:11 PM EDTSpecial Weather StatementMFLGlades34 min
Aug 25, 3:44 PM EDTSpecial Marine WarningMFL91 min
Aug 25, 4:07 PM EDTSpecial Marine WarningMFL83 min
Aug 25, 5:09 PM EDTSpecial Marine WarningMFL81 min
Aug 25, 5:42 PM EDTSpecial Marine WarningMFL48 min
Aug 25, 6:17 PM EDTSpecial Marine WarningMFL43 min
Aug 25, 6:25 PM EDTSpecial Weather StatementMFLMiami-Dade50 min

Nearby

Severe Thunderstorm Warnings in Florida, 2021Every severe thunderstorm warning in 2021

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.