Alert archive / Florida / Areal Flood Warnings in 2021

Areal Flood Warning 13, NWS Melbourne, FL

November 21, 2021Saint Lucie County, Florida

NWS Melbourne, FL issued this areal flood warning at Nov 21, 2021, 2:32 PM EST for Saint Lucie County, Florida. It was in force for 2 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: Nov 21, 2021, 2:32 PM EST (19:32 UTC)
Expired: Nov 21, 2021, 5:00 PM EST
In force: 2 hr
Issued by: NWS Melbourne, FL
Area: Storm-based polygon
Flood severity: None

County Saint Lucie County, FL

The radar

The Melbourne radar (KMLB), 74 km from the middle of the area, began a volume at 19:33 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, 7.5 hours before the alert went out and 112 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: 170 J/kg
Mixed-layer CIN: -23 J/kg
Mixed-layer LCL: 879 m above ground
0-6 km bulk shear: 26 kt
0-1 km storm-relative helicity: 11 m²/s²
0-3 km storm-relative helicity: 154 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

630 
WGUS42 KMLB 211932
FLWMLB

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Flood Warning
National Weather Service Melbourne FL
232 PM EST Sun Nov 21 2021

FLC111-212200-
/O.NEW.KMLB.FA.W.0013.211121T1932Z-211121T2200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
St. Lucie FL-
232 PM EST Sun Nov 21 2021

...FLOOD WARNING IN EFFECT UNTIL 5 PM EST THIS AFTERNOON...

* WHAT...Urban area and Small stream flooding caused by excessive 
  rainfall is expected.

* WHERE...A portion of east central Florida, including the following 
  area, St. Lucie.

* WHEN...Until 500 PM EST.

* IMPACTS...Flooding of rivers, creeks, streams, and other low-lying 
  and flood-prone locations is imminent or occurring.

* ADDITIONAL DETAILS...
  - At 230 PM EST, Doppler radar and automated rain gauges
    indicated heavy rain due to thunderstorms. Flooding is
    ongoing or expected to begin shortly in the warned area.
    Between 5 and 7 inches of rain has fallen in rural
    northwestern Saint Lucie County, and 3 to 5 inches has fallen
    in the Fort Pierce area.
  - Additional rainfall amounts of 2 to 3 inches are possible in
    the warned area.
  - Some locations that will experience flooding include...
    Fort Pierce, Lakewood Park, Treasure Coast Airport, Fort
    Pierce North, Fort Pierce South, Saint Lucie Village, and
    Saint Lucie.
  - http://www.weather.gov/safety/flood

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Please report observed flooding to local emergency services or law 
enforcement and request they pass this information to the National 
Weather Service when you can do so safely.

&&

LAT...LON 2740 8047 2739 8068 2756 8068 2756 8035
      2753 8034 2742 8031


$$

Rodriguez

The office that day

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

Issued	Product	Office	Counties	Lasted
Nov 21, 8:38 AM EST	Areal Flood Advisory	MLB	Saint Lucie	112 min
Nov 21, 12:21 PM EST	Areal Flood Advisory	MLB	Saint Lucie	114 min
Nov 21, 1:00 PM EST	Areal Flood Advisory	MLB	Saint Lucie	75 min
Nov 21, 1:37 PM EST	Areal Flood Warning	MLB	Saint Lucie	27 min
Nov 21, 2:04 PM EST	Flash Flood Warning	MLB	Saint Lucie	3 hr
Nov 21, 3:36 PM EST	Areal Flood Advisory	MLB	Martin, Saint Lucie	84 min
Nov 21, 5:00 PM EST	Areal Flood Warning	MLB	Saint Lucie	2 hr

Nearby

Areal Flood Warnings in Florida, 2021 Every areal 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.