Alert archive / Florida / Flash Flood Warnings in 2020

Flash Flood Warning 5, NWS Melbourne, FL

October 1, 2020Martin County, Saint Lucie County, Florida

NWS Melbourne, FL issued this flash flood warning at Oct 1, 2020, 4:53 PM EDT for Martin County, Saint Lucie 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, 4:53 PM EDT (20:53 UTC)
Expired: Oct 1, 2020, 7:34 PM EDT
In force: 3 hr
Issued by: NWS Melbourne, FL
Area: Storm-based polygon
Flood severity: None

Counties Martin County, FL, Saint Lucie County, FL

The radar

The Melbourne radar (KMLB), 103 km from the middle of the area, began a volume at 20:54 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

Cape Canaveral, FL (KXMR), launched 12:00Z, 8.9 hours before the alert went out and 137 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: 5 J/kg
Mixed-layer CIN: -202 J/kg
Mixed-layer LCL: 910 m above ground
0-6 km bulk shear: 26 kt
0-1 km storm-relative helicity: 64 m²/s²
0-3 km storm-relative helicity: 144 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.0

Open this sounding in Storm Lab

The text

As transmitted.

736 
WGUS52 KMLB 012053
FFWMLB
FLC085-111-020000-
/O.NEW.KMLB.FF.W.0005.201001T2053Z-201002T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

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

The National Weather Service in Melbourne has issued a

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

* Until 800 PM EDT.

* At 453 PM EDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 3 and 4 inches of rain 
  have fallen in the last 2 hours. Flash flooding is ongoing or 
  expected to begin shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Doppler radar.

  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...
  Stuart, Jensen Beach, Nettles Island, North River Shores, Ocean 
  Breeze Park, Waveland and Hutchinson Island South.

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.

&&

LAT...LON 2725 8030 2728 8030 2730 8022 2731 8022
      2732 8020 2725 8015 2724 8019 2722 8027
      2721 8030 2724 8030 2724 8029

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...1-3 INCHES IN 3 HOURS 

$$

Kelly

1 follow-up statement

855 
WGUS72 KMLB 012334
FFSMLB

Flash Flood Statement
National Weather Service Melbourne FL
734 PM EDT Thu Oct 1 2020

FLC085-111-012344-
/O.CAN.KMLB.FF.W.0005.000000T0000Z-201002T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Martin FL-St. Lucie FL-
734 PM EDT Thu Oct 1 2020

...FLASH FLOOD WARNING IS CANCELLED FOR NORTHEASTERN MARTIN AND 
SOUTHEASTERN ST. LUCIE COUNTIES...

The heavy rain has ended. However, motorists will continue to 
encounter standing water on many roads. Motorists should exercise 
extreme caution now that darkness has fallen. Do not drive your 
vehicle where water covers the road.

A Flood Watch remains in effect until 400 PM EDT Friday for Saint 
Lucie and Martin counties.

LAT...LON 2725 8030 2728 8030 2730 8022 2731 8022
      2732 8020 2725 8015 2724 8019 2722 8027
      2721 8030 2724 8030 2724 8029

$$

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, 2:12 AM EDT	Flash Flood Warning	MLB	Martin	3 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, 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.