Alert archive / Florida / Flash Flood Warnings in 2021

Flash Flood Warning 2, NWS Miami, FL

April 20, 2021Miami-Dade County, Florida

NWS Miami, FL issued this flash flood warning at Apr 20, 2021, 2:25 AM EDT for Miami-Dade County, Florida. It was in force for 3 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Apr 20, 2021, 2:25 AM EDT (06:25 UTC)
Expired
Apr 20, 2021, 5:30 AM EDT
In force
3 hr
Issued by
NWS Miami, FL
Area
Storm-based polygon
Flood severity
None

County Miami-Dade County, FL

The radar

The Miami radar (KAMX), 27 km from the middle of the area, began a volume at 06:27 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, 6.4 hours before the alert went out and 9 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 2021-04-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1822 joules per kilogram.LCLLFCEL10008507005003002001001 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 2021-04-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 42 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
1822 J/kg
Mixed-layer CIN
-7 J/kg
Mixed-layer LCL
975 m above ground
0-6 km bulk shear
37 kt
0-1 km storm-relative helicity
42 m²/s²
0-3 km storm-relative helicity
116 m²/s²
Significant tornado parameter
0.6
Supercell composite
3.6

Open this sounding in Storm Lab

The text

As transmitted.

495 
WGUS52 KMFL 200625
FFWMFL
FLC086-200930-
/O.NEW.KMFL.FF.W.0002.210420T0625Z-210420T0930Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Miami FL
225 AM EDT Tue Apr 20 2021

The National Weather Service in Miami has issued a

* Flash Flood Warning for...
  Northern Miami-Dade County in southeastern Florida...

* Until 530 AM EDT.

* At 225 AM EDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 2 and 3 inches of rain 
  have fallen. Additional rainfall amounts of 2 to 3 inches are 
  possible in the warned area. Flash flooding is ongoing or expected 
  to begin shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar.

  IMPACT...Flash flooding of small creeks and streams, urban
           areas, highways, streets and underpasses as well as
           other poor drainage and low-lying areas.

* Some locations that will experience flash flooding include...
  Miami, Hialeah, Miami Beach, Coral Gables, South Miami, Surfside, 
  Virginia Key, Miami Gardens, North Miami, Doral, North Miami 
  Beach, Opa-Locka, Miami Springs, Miami Shores, North Bay Village, 
  West Miami, El Portal, Liberty City, Little Haiti and Downtown 
  Miami.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

Be especially cautious at night when it is harder to recognize the 
dangers of flooding.

&&

LAT...LON 2571 8025 2578 8036 2592 8023 2590 8006
      2574 8013 2568 8020

FLASH FLOOD...RADAR INDICATED

$$

Weinman
1 follow-up statement
135 
WGUS72 KMFL 200719
FFSMFL

Flash Flood Statement
National Weather Service Miami FL
319 AM EDT Tue Apr 20 2021

FLC086-200930-
/O.CON.KMFL.FF.W.0002.000000T0000Z-210420T0930Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Miami-Dade FL-
319 AM EDT Tue Apr 20 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 530 AM EDT EARLY THIS 
MORNING FOR NORTHERN MIAMI-DADE COUNTY...

At 319 AM EDT, Between 2 and 4 inches of rain have fallen across the 
warned area. Flash flooding is potentially ongoing. While the heavy 
rain is beginning to subside, additional clusters of heavy rain may 
still affect the warned area over the next couple hours.

HAZARD...Flash flooding caused by thunderstorms.

SOURCE...Radar.

IMPACT...Flash flooding of small creeks and streams, urban areas,
         highways, streets and underpasses as well as other poor
         drainage and low-lying areas.

Some locations that will experience flash flooding include...
  Miami, Hialeah, Miami Beach, Coral Gables, South Miami, Surfside, 
  Virginia Key, Miami Gardens, North Miami, Doral, North Miami 
  Beach, Opa-Locka, Miami Springs, Miami Shores, North Bay Village, 
  West Miami, El Portal, Liberty City, Little Haiti and Downtown 
  Miami.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

Be especially cautious at night when it is harder to recognize the 
dangers of flooding.

Be aware of your surroundings and do not drive on flooded roads.

&&

LAT...LON 2571 8025 2578 8036 2592 8023 2590 8006
      2574 8013 2568 8020

FLASH FLOOD...RADAR INDICATED

$$

Weinman

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 19, 9:25 PM EDTSpecial Weather StatementMFLMiami-Dade50 min
Apr 19, 9:38 PM EDTSpecial Marine WarningMFL97 min
Apr 19, 9:41 PM EDTSpecial Weather StatementMFLMiami-Dade34 min
Apr 19, 10:00 PM EDTSpecial Weather StatementMFLMiami-Dade45 min
Apr 19, 10:03 PM EDTSpecial Marine WarningMFL87 min
Apr 19, 10:11 PM EDTSpecial Weather StatementMFLMonroe64 min
Apr 19, 10:44 PM EDTSpecial Weather StatementMFLBroward46 min
Apr 19, 11:01 PM EDTSpecial Weather StatementMFLMiami-Dade44 min
Apr 19, 11:04 PM EDTSpecial Marine WarningMFL56 min
Apr 19, 11:25 PM EDTSpecial Marine WarningMFL65 min
Apr 19, 11:41 PM EDTSpecial Marine WarningMFL64 min
Apr 19, 11:50 PM EDTSpecial Weather StatementMFLMiami-Dade40 min
Apr 19, 11:56 PM EDTSpecial Marine WarningMFL94 min
Apr 20, 12:18 AM EDTSpecial Weather StatementMFLMiami-Dade42 min
Apr 20, 12:24 AM EDTAreal Flood AdvisoryMFLBroward, Miami-Dade4 hr
Apr 20, 12:26 AM EDTSpecial Marine WarningMFL45 min
Apr 20, 1:28 AM EDTSpecial Marine WarningMFL92 min
Apr 20, 1:32 AM EDTSpecial Weather StatementMFLMonroe58 min
Apr 20, 2:19 AM EDTAreal Flood AdvisoryMFLMiami-Dade3 hr
Apr 20, 2:32 AM EDTSevere Thunderstorm WarningMFLMiami-Dade58 min
Apr 20, 2:34 AM EDTSpecial Weather StatementMFLMiami-Dade56 min
Apr 20, 2:36 AM EDTSpecial Weather StatementMFLCollier39 min
Apr 20, 2:37 AM EDTSpecial Marine WarningMFL83 min
Apr 20, 2:55 AM EDTSpecial Weather StatementMFLMiami-Dade50 min
Apr 20, 3:02 AM EDTSpecial Marine WarningMFL58 min
Apr 20, 3:03 AM EDTSpecial Weather StatementMFLBroward57 min
Apr 20, 5:42 AM EDTSpecial Weather StatementMFLPalm Beach48 min
Apr 20, 7:42 AM EDTSpecial Marine WarningMFL63 min
Apr 20, 8:34 AM EDTSpecial Marine WarningMFL26 min

Nearby

Flash Flood Warnings in Florida, 2021Every flash flood 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.