Alert archive / Florida / Flash Flood Warnings in 2020

Flash Flood Warning 4, NWS Melbourne, FL

October 1, 2020Martin County, Florida

NWS Melbourne, FL issued this flash flood warning at Oct 1, 2020, 4:33 AM EDT for Martin County, Florida. It was in force for 4 hr. 6 reports 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
Oct 1, 2020, 4:33 AM EDT (08:33 UTC)
Expired
Oct 1, 2020, 9:00 AM EDT
In force
4 hr
Issued by
NWS Melbourne, FL
Area
Storm-based polygon
Damage threat
Considerable
Flood severity
None

County Martin County, FL

The radar

The Melbourne radar (KMLB), 126 km from the middle of the area, began a volume at 08:32 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
Oct 1, 5:30 AM EDTFLOOD2 Nnw Hobe Sound, FLMARTIN COUNTY EMERGENCY MANAGEMENT REPORTS SE OSPREY STREET IN HOBE SOUND IS IMPASSABLE DUE TO HIGH WATER.
Oct 1, 5:52 AM EDTHEAVY RAIN 5.554 Nw Hobe Sound, FLWEATHER UNDERGROUND STATION IN HOBE SOUND HAS MEASURED 5.55 INCHES OF RAIN SINCE 11 PM LAST NIGHT.
Oct 1, 5:52 AM EDTHEAVY RAIN 5.991 Nnw Hobe Sound, FLWEATHER UNDERGROUND STATION IN HOBE SOUND HAS MEASURED 5.99 INCHES OF RAIN SINCE 11 PM LAST NIGHT.
Oct 1, 5:53 AM EDTHEAVY RAIN 3.58Jonathan Dickinson Stat, FLSFWMD RAIN GAUAGE AT JD STATE PARK HAS MEASURED 3.58 INCHES OF RAIN.
Oct 1, 5:53 AM EDTHEAVY RAIN 4.55 Nnw Hobe Sound, FLWEATHER UNDERGROUND STATION IN PORT SALERNO HAS MEASURED 4.50 INCHES OF RAIN SINCE 11 PM LAST NIGHT.
Oct 1, 5:53 AM EDTHEAVY RAIN 6.054 Sw Jupiter Island, FLWEATHER UNDERGROUND STATION IN TEQUESTA HAS MEASURED 6.05 INCHES OF RAIN SINCE 11 PM LAST NIGHT.

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, 8.6 hours before the alert went out and 139 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 2020-10-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1202 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 2020-10-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 34 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
1202 J/kg
Mixed-layer CIN
-3 J/kg
Mixed-layer LCL
803 m above ground
0-6 km bulk shear
19 kt
0-1 km storm-relative helicity
34 m²/s²
0-3 km storm-relative helicity
43 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.5

Open this sounding in Storm Lab

The text

As transmitted.

907 
WGUS52 KMLB 010833
FFWMLB
FLC085-011300-
/O.NEW.KMLB.FF.W.0004.201001T0833Z-201001T1300Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Melbourne FL
433 AM EDT Thu Oct 1 2020

The National Weather Service in Melbourne has issued a

* Flash Flood Warning for...
  Eastern Martin County in east central Florida...

* Until 900 AM EDT.

* At 433 AM EDT, Doppler radar and automated rain gauges indicated 
  thunderstorms producing heavy rain across the warned area. Between 
  4 and 5.5 inches of rain have fallen. Flash flooding is ongoing or 
  expected to begin shortly.

  HAZARD...Life threatening flash flooding. Thunderstorms
           producing flash flooding.

  SOURCE...Doppler radar and automated gauges.

  IMPACT...Life threatening flash flooding of creeks and streams,
           urban areas, highways, streets and underpasses.

* Some locations that will experience flash flooding include...
  Hobe Sound, Port Salerno, Stuart, Jupiter Island, and Jonathan 
  Dickinson State Park.

Water could enter homes in some vulnerable neighborhoods in Hobe 
Sound that have been experiencing flooding issues over the past few 
weeks.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Warning means that flooding is imminent or occurring. 
Residents living along streams and creeks should take immediate 
precautions to protect life and property.

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.

Please report flooding to your local law enforcement agency when you 
can do so safely.

&&

LAT...LON 2715 8024 2717 8020 2717 8015 2697 8006
      2697 8014 2696 8014 2696 8021

FLASH FLOOD...RADAR AND GAUGE INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
EXPECTED RAINFALL...2-4 INCHES IN 3 HOURS 

$$

Rodriguez
3 follow-up statements
557 
WGUS72 KMLB 010937
FFSMLB

Flash Flood Statement
National Weather Service Melbourne FL
537 AM EDT Thu Oct 1 2020

FLC085-011300-
/O.CON.KMLB.FF.W.0004.000000T0000Z-201001T1300Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Martin FL-
537 AM EDT Thu Oct 1 2020

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 9 AM EDT THIS MORNING 
FOR EASTERN MARTIN COUNTY...

At 537 AM EDT, Doppler radar and automated rain gauges indicated 
thunderstorms producing heavy rain across the warned area. Between 5 
and 6.5 inches of rain have fallen. Flash flooding is ongoing or 
expected to begin shortly. Additional rainfall amounts of 2 to 4 
inches will be possible over the next few hours.

HAZARD...Life threatening flash flooding. Thunderstorms producing
         flash flooding.

SOURCE...Doppler radar and automated gauges.

IMPACT...Life threatening flash flooding of creeks and streams,
         urban areas, highways, streets and underpasses.

Some locations that will experience flash flooding include...
  Hobe Sound, Port Salerno, Stuart, Jupiter Island, and Jonathan 
  Dickinson State Park.

Water could enter homes in some vulnerable neighborhoods in Hobe 
Sound that have been experiencing flooding issues over the past few 
weeks.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Warning means that flooding is imminent or occurring. 
Residents living along streams and creeks should take immediate 
precautions to protect life and property.

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

Please report flooding to your local law enforcement agency when you 
can do so safely.

&&

LAT...LON 2715 8024 2717 8020 2717 8015 2697 8006
      2697 8014 2696 8014 2696 8021

FLASH FLOOD...RADAR AND GAUGE INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
EXPECTED RAINFALL...2-4 INCHES IN 3 HOURS 

$$

Rodriguez
707 
WGUS72 KMLB 011052
FFSMLB

Flash Flood Statement
National Weather Service Melbourne FL
652 AM EDT Thu Oct 1 2020

FLC085-011300-
/O.CON.KMLB.FF.W.0004.000000T0000Z-201001T1300Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Martin FL-
652 AM EDT Thu Oct 1 2020

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 9 AM EDT THIS MORNING 
FOR EASTERN MARTIN COUNTY...

At 652 AM EDT, emergency management reported thunderstorms producing 
heavy rain across the warned area. Between 5.5 and 7 inches of rain 
have fallen. Flash flooding is ongoing. While most of the heavy rain 
has ended in coastal Martin County, additional heavy showers could 
produce between 1 to 3 inches of rain through late morning.

Several roads in Hobe Sound are closed due to high standing water, 
including Dixie Highway, Heritage Boulevard, Osprey Street and 
several other local roads.

HAZARD...Life threatening flash flooding. Thunderstorms producing
         flash flooding.

SOURCE...Emergency management.

IMPACT...Life threatening flash flooding of creeks and streams,
         urban areas, highways, streets and underpasses.

Some locations that will experience flash flooding include...
  Stuart, Jupiter Island, Hobe Sound, Port Salerno, Sewall's Point, 
  Hobe Sound Beach, Jonathan Dickinson State Park and Hobe Sound 
  Wildlife Refuge.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Warning means that flooding is imminent or occurring. 
Residents living along streams and creeks should take immediate 
precautions to protect life and property.

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

Please report flooding to your local law enforcement agency when you 
can do so safely.

&&

LAT...LON 2715 8024 2717 8020 2717 8015 2697 8006
      2697 8014 2696 8014 2696 8021

FLASH FLOOD...OBSERVED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
EXPECTED RAINFALL...1-3 INCHES IN 2 HOURS 

$$

Rodriguez
528 
WGUS72 KMLB 011255
FFSMLB

Flash Flood Statement
National Weather Service Melbourne FL
855 AM EDT Thu Oct 1 2020

FLC085-011305-
/O.EXP.KMLB.FF.W.0004.000000T0000Z-201001T1300Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Martin FL-
855 AM EDT Thu Oct 1 2020

...FLASH FLOOD WARNING AT 9 AM EDT THIS MORNING FOR EASTERN MARTIN 
COUNTY HAS BEEN REPLACED WITH A FLOOD WARNING...

The heavy rain has ended. Please continue to heed remaining road 
closures.

A Flood Watch remains in effect until 400 AM EDT Friday for a 
portion of east central Florida.

LAT...LON 2715 8024 2717 8020 2717 8015 2697 8006
      2697 8014 2696 8014 2696 8021

$$

CL

The office that day

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

IssuedProductOfficeCountiesLasted
Oct 1, 12:57 AM EDTAreal Flood AdvisoryMLBMartin24 min
Oct 1, 1:21 AM EDTAreal Flood WarningMLBMartin4 hr
Oct 1, 2:12 AM EDTFlash Flood WarningMLBMartin3 hr
Oct 1, 3:09 AM EDTFlood WatchMLBLake, Orange, Osceola, Seminole, Volusia4 days
Oct 1, 5:33 AM EDTAreal Flood WarningMLBIndian River, Martin, Saint Lucie3 hr
Oct 1, 8:54 AM EDTAreal Flood WarningMLBMartin3 hr
Oct 1, 10:09 AM EDTAreal Flood AdvisoryMLBSaint Lucie4 hr
Oct 1, 1:30 PM EDTAreal Flood WarningMLBSaint Lucie90 min
Oct 1, 2:57 PM EDTAreal Flood WarningMLBMartin, Saint Lucie3 hr
Oct 1, 3:46 PM EDTAreal Flood AdvisoryMLBIndian River, Saint Lucie119 min
Oct 1, 4:53 PM EDTFlash Flood WarningMLBMartin, Saint Lucie3 hr
Oct 1, 5:59 PM EDTAreal Flood AdvisoryMLBIndian River, Martin, Saint Lucie3 hr
Oct 1, 6:30 PM EDTAreal Flood WarningMLBMartin, Saint Lucie5 hr

Nearby

Flash Flood Warnings in Florida, 2020Every flash flood warning in 2020

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.