Alert archive / Florida / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 73, NWS Miami, FL

December 21, 2021Miami-Dade County, Florida

NWS Miami, FL issued this severe thunderstorm warning at Dec 21, 2021, 11:08 AM EST for Miami-Dade County, Florida. It was in force for 22 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Dec 21, 2021, 11:08 AM EST (16:08 UTC)
Expired
Dec 21, 2021, 11:30 AM EST
In force
22 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), 27 km from the middle of the area, began a volume at 16:09 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, 4.1 hours before the alert went out and 17 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 2021-12-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 601 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 2021-12-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 133 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
601 J/kg
Mixed-layer CIN
-22 J/kg
Mixed-layer LCL
844 m above ground
0-6 km bulk shear
37 kt
0-1 km storm-relative helicity
133 m²/s²
0-3 km storm-relative helicity
173 m²/s²
Significant tornado parameter
0.3
Supercell composite
3.4

Open this sounding in Storm Lab

The text

As transmitted.

405 
WUUS52 KMFL 211608
SVRMFL
FLC086-211630-
/O.NEW.KMFL.SV.W.0073.211221T1608Z-211221T1630Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Miami FL
1108 AM EST Tue Dec 21 2021

The National Weather Service in Miami has issued a

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

* Until 1130 AM EST.

* At 1107 AM EST, a severe thunderstorm was located over Key
  Biscayne, moving east 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, Key Biscayne, Virginia Key and Fisher Island. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 2566 8021 2573 8022 2577 8016 2578 8012
      2570 8010
TIME...MOT...LOC 1607Z 254DEG 26KT 2572 8018 

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

$$

Kelly
1 follow-up statement
454 
WWUS52 KMFL 211620
SVSMFL

Severe Weather Statement
National Weather Service Miami FL
1120 AM EST Tue Dec 21 2021

FLC086-211630-
/O.EXP.KMFL.SV.W.0073.000000T0000Z-211221T1630Z/
Miami-Dade FL-
1120 AM EST Tue Dec 21 2021

...THE SEVERE THUNDERSTORM WARNING FOR CENTRAL MIAMI-DADE COUNTY WILL
EXPIRE AT 1130 AM EST...
        
The storm which prompted the warning has moved out of the area.
Therefore, the warning will be allowed to expire.

LAT...LON 2566 8021 2573 8022 2577 8016 2578 8012
      2570 8010
TIME...MOT...LOC 1620Z 254DEG 26KT 2574 8008 

$$

Kelly

The office that day

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

IssuedProductOfficeCountiesLasted
Dec 20, 7:22 PM ESTRip Current StatementMFLBroward, Collier, Miami-Dade, Palm Beach48 hr
Dec 21, 1:34 AM ESTGale WarningMFL20 hr
Dec 21, 1:34 AM ESTSmall Craft AdvisoryMFL8 hr
Dec 21, 1:34 AM ESTSmall Craft AdvisoryMFL44 hr
Dec 21, 3:28 AM ESTSpecial Marine WarningMFL62 min
Dec 21, 3:34 AM ESTWind AdvisoryMFLCollier, Glades, Hendry, Palm Beach14 hr
Dec 21, 4:06 AM ESTSpecial Marine WarningMFL39 min
Dec 21, 4:38 AM ESTSpecial Marine WarningMFL52 min
Dec 21, 5:18 AM ESTSpecial Marine WarningMFL57 min
Dec 21, 5:41 AM ESTSpecial Weather StatementMFLCollier49 min
Dec 21, 7:45 AM ESTSpecial Marine WarningMFL30 min
Dec 21, 7:57 AM ESTSpecial Weather StatementMFLPalm Beach33 min
Dec 21, 8:06 AM ESTSpecial Marine WarningMFL39 min
Dec 21, 8:27 AM ESTSpecial Weather StatementMFLCollier48 min
Dec 21, 8:59 AM ESTSpecial Weather StatementMFLBroward46 min
Dec 21, 9:45 AM ESTSpecial Weather StatementMFLMiami-Dade45 min
Dec 21, 10:25 AM ESTSpecial Weather StatementMFLMiami-Dade50 min
Dec 21, 10:28 AM ESTSpecial Marine WarningMFL92 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.