Alert archive / Florida / Flash Flood Warnings in 2020

Flash Flood Warning 3, NWS Melbourne, FL

October 1, 2020Martin County, Florida

NWS Melbourne, FL issued this flash flood warning at Oct 1, 2020, 2:12 AM EDT for Martin 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: Oct 1, 2020, 2:12 AM EDT (06:12 UTC)
Expired: Oct 1, 2020, 5:00 AM EDT
In force: 3 hr
Issued by: NWS Melbourne, FL
Area: Storm-based polygon
Flood severity: None

County Martin County, FL

The radar

The Melbourne radar (KMLB), 123 km from the middle of the area, began a volume at 06:14 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, 6.2 hours before the alert went out and 141 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: 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.

786 
WGUS52 KMLB 010612
FFWMLB
FLC085-010900-
/O.NEW.KMLB.FF.W.0003.201001T0612Z-201001T0900Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

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

The National Weather Service in Melbourne has issued a

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

* Until 500 AM EDT.

* At 212 AM EDT, Doppler radar and automated rain gauges indicated 
  thunderstorms producing heavy rain across the warned area. Between 
  2.5 and 4 inches of rain have fallen. Flash flooding is ongoing or 
  expected to begin shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Doppler radar and automated gauges.

  IMPACT...Flooding of small creeks and streams, urban areas,
           highways, streets and underpasses as well as other
           drainage and low lying areas.

* Some locations that will experience flash flooding include...
  Hobe Sound, Port Salerno, and south areas of Stuart and Palm City.

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.

&&

LAT...LON 2713 8024 2714 8022 2715 8019 2715 8016
      2715 8015 2713 8014 2707 8011 2706 8012
      2705 8012 2702 8015 2698 8018 2698 8024
      2705 8024 2710 8025

FLASH FLOOD...RADAR AND GAUGE INDICATED
EXPECTED RAINFALL...2-3 INCHES IN 3 HOURS 

$$

Rodriguez

1 follow-up statement

957 
WGUS72 KMLB 010708
FFSMLB

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

FLC085-010900-
/O.CON.KMLB.FF.W.0003.000000T0000Z-201001T0900Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Martin FL-
308 AM EDT Thu Oct 1 2020

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 5 AM EDT EARLY THIS 
MORNING FOR SOUTHEASTERN MARTIN COUNTY...

At 308 AM EDT, Doppler radar and automated rain gauges indicated 
thunderstorms producing heavy rain across the warned area. Between 
2.5 and 4 inches of rain have fallen. Flash flooding is ongoing or 
expected to begin shortly. While most of the heavy rain has ended, 
additional heavy showers could develop near Hobe Sound and Port 
Salerno in the next two hours.

HAZARD...Flash flooding caused by thunderstorms.

SOURCE...Doppler radar and automated gauges.

IMPACT...Flooding of small creeks and streams, urban areas,
         highways, streets and underpasses as well as other
         drainage and low lying areas.

Some locations that will experience flash flooding include...
  Hobe Sound, Port Salerno, and south areas of Stuart and Palm City.

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. 

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 2713 8024 2714 8022 2715 8019 2715 8016
      2715 8015 2713 8014 2707 8011 2706 8012
      2705 8012 2702 8015 2698 8018 2698 8024
      2705 8024 2710 8025

FLASH FLOOD...RADAR AND GAUGE INDICATED
EXPECTED RAINFALL...1-2 INCHES IN 2 HOURS 

$$

Rodriguez

The office that day

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

Issued	Product	Office	Counties	Lasted
Oct 1, 12:57 AM EDT	Areal Flood Advisory	MLB	Martin	24 min
Oct 1, 1:21 AM EDT	Areal Flood Warning	MLB	Martin	4 hr
Oct 1, 3:09 AM EDT	Flood Watch	MLB	Lake, Orange, Osceola, Seminole, Volusia	4 days
Oct 1, 4:33 AM EDT	Flash Flood Warning Considerable damage threat	MLB	Martin	4 hr
Oct 1, 5:33 AM EDT	Areal Flood Warning	MLB	Indian River, Martin, Saint Lucie	3 hr
Oct 1, 8:54 AM EDT	Areal Flood Warning	MLB	Martin	3 hr
Oct 1, 10:09 AM EDT	Areal Flood Advisory	MLB	Saint Lucie	4 hr
Oct 1, 1:30 PM EDT	Areal Flood Warning	MLB	Saint Lucie	90 min
Oct 1, 2:57 PM EDT	Areal Flood Warning	MLB	Martin, Saint Lucie	3 hr
Oct 1, 3:46 PM EDT	Areal Flood Advisory	MLB	Indian River, Saint Lucie	119 min
Oct 1, 4:53 PM EDT	Flash Flood Warning	MLB	Martin, Saint Lucie	3 hr
Oct 1, 5:59 PM EDT	Areal Flood Advisory	MLB	Indian River, Martin, Saint Lucie	3 hr
Oct 1, 6:30 PM EDT	Areal Flood Warning	MLB	Martin, Saint Lucie	5 hr

Nearby

Flash Flood Warnings in Florida, 2020 Every 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.