Alert archive / Florida / Tornado Warnings in 2020

Tornado Warning 11, NWS Melbourne, FL

April 20, 2020Martin County, Florida

NWS Melbourne, FL issued this tornado warning at Apr 20, 2020, 5:21 PM EDT for Martin County, Florida. It was in force for 24 min. 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: Apr 20, 2020, 5:21 PM EDT (21:21 UTC)
Expired: Apr 20, 2020, 5:45 PM EDT
In force: 24 min
Issued by: NWS Melbourne, FL
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 0.75 in

County Martin County, FL

The radar

The Melbourne radar (KMLB), 105 km from the middle of the area, began a volume at 21:21 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

Time	Report	Where	Remark
Apr 20, 5:28 PM EDT	TSTM WND GST 60	Witham Field, FL	KSUA AWOS REPORTED A PEAK WIND OF 52 KNOTS/60 MPH FROM THE WEST VIA AIR TRAFFIC CONTROL TOWER.
Apr 20, 5:30 PM EDT	HAIL 1	5 Sw Jensen Beach, FL	STORM SPOTTER REPORTED QUARTER SIZED HAIL AT MONARCH COUNTRY CLUB IN PALM CITY.
Apr 20, 5:35 PM EDT	HAIL 1	5 Sw Jensen Beach, FL	TRAINED SPOTTER REPORTED QUARTER SIZED HAIL IN PALM CITY. ESTIMATED WIND GUST OF 40 MPH.
Apr 20, 5:36 PM EDT	HAIL 0.7	Stuart, FL	TRAINED SPOTTER REPORTED DIME SIZED HAIL IN STUART.
Apr 20, 5:36 PM EDT	HAIL 1	5 Sw Jensen Beach, FL	TRAINED SPOTTER REPORTED QUARTER SIZED HAIL.
Apr 20, 5:49 PM EDT	TSTM WND DMG	Palm City, FL	EMERGENCY MANAGMENT REPORTED A TREE ON A CAR IN PALM CITY.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Cape Canaveral, FL (KXMR), launched 12:00Z, 9.4 hours before the alert went out and 140 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: 2398 J/kg
Mixed-layer CIN: -21 J/kg
Mixed-layer LCL: 793 m above ground
0-6 km bulk shear: 55 kt
0-1 km storm-relative helicity: 224 m²/s²
0-3 km storm-relative helicity: 268 m²/s²
Significant tornado parameter: 4.0
Supercell composite: 18.3

Open this sounding in Storm Lab

The text

As transmitted.

655 
WFUS52 KMLB 202121
TORMLB
FLC085-202145-
/O.NEW.KMLB.TO.W.0011.200420T2121Z-200420T2145Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Melbourne FL
521 PM EDT Mon Apr 20 2020

The National Weather Service in Melbourne has issued a

* Tornado Warning for...
  Northeastern Martin County in east central Florida...

* Until 545 PM EDT.
    
* At 520 PM EDT, a severe thunderstorm capable of producing a tornado
  was located 7 miles south of Tradition, or 9 miles southwest of
  Port Saint Lucie, moving east at 40 mph.

  HAZARD...Tornado.

  SOURCE...Radar indicated rotation.

  IMPACT...Flying debris will be dangerous to those caught without 
           shelter. Mobile homes will be damaged or destroyed. 
           Damage to roofs, windows, and vehicles will occur.  Tree 
           damage is likely.

* This dangerous storm will be near...
  Palm City and North River Shores around 530 PM EDT.
  Stuart, Port Salerno and Sewall's Point around 540 PM EDT.

Other locations impacted by this tornadic thunderstorm include Rio.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to an interior room on the lowest floor of a
sturdy building. Avoid windows. If you are outdoors, in a mobile
home, or in a vehicle, move to the closest substantial shelter and
protect yourself from flying debris.

&&

LAT...LON 2710 8047 2719 8049 2721 8045 2721 8029
      2722 8029 2724 8031 2723 8029 2726 8028
      2726 8023 2728 8024 2728 8022 2729 8022
      2726 8021 2726 8020 2729 8021 2731 8018
      2721 8013 2710 8010
TIME...MOT...LOC 2120Z 258DEG 36KT 2716 8042 

TORNADO...RADAR INDICATED
HAIL...<.75IN

$$

Kelly

2 follow-up statements

380 
WWUS52 KMLB 202136
SVSMLB

Severe Weather Statement
National Weather Service Melbourne FL
536 PM EDT Mon Apr 20 2020

FLC085-202145-
/O.CON.KMLB.TO.W.0011.000000T0000Z-200420T2145Z/
Martin FL-
536 PM EDT Mon Apr 20 2020

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 545 PM EDT FOR
NORTHEASTERN MARTIN COUNTY...
    
At 535 PM EDT, a severe thunderstorm capable of producing a tornado
was located over Palm City, moving east at 45 mph.

HAZARD...Tornado and quarter size hail.

SOURCE...Radar indicated rotation.

IMPACT...Flying debris will be dangerous to those caught without 
         shelter. Mobile homes will be damaged or destroyed. Damage 
         to roofs, windows, and vehicles will occur.  Tree damage is 
         likely.

This dangerous storm will be near...
  Hobe Sound around 540 PM EDT.

Other locations impacted by this tornadic thunderstorm include Hobe
Sound Wildlife Refuge.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to an interior room on the lowest floor of a
sturdy building. Avoid windows. If you are outdoors, in a mobile
home, or in a vehicle, move to the closest substantial shelter and
protect yourself from flying debris.

&&

LAT...LON 2710 8031 2716 8032 2719 8031 2721 8029
      2721 8013 2716 8012 2710 8010
TIME...MOT...LOC 2135Z 266DEG 37KT 2715 8023 

TORNADO...RADAR INDICATED
HAIL...1.00IN

$$

Kelly

084 
WWUS52 KMLB 202146
SVSMLB

Severe Weather Statement
National Weather Service Melbourne FL
546 PM EDT Mon Apr 20 2020

FLC085-202156-
/O.EXP.KMLB.TO.W.0011.000000T0000Z-200420T2145Z/
Martin FL-
546 PM EDT Mon Apr 20 2020

...THE TORNADO WARNING FOR NORTHEASTERN MARTIN COUNTY HAS EXPIRED...
        
The storm which prompted the warning has moved out of the area.
Therefore, the warning has been allowed to expire.  However heavy
rain is still possible with this thunderstorm.

LAT...LON 2710 8031 2716 8032 2719 8031 2721 8029
      2721 8013 2716 8012 2710 8010
TIME...MOT...LOC 2146Z 258DEG 36KT 2717 8012 

$$

Kelly

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 20, 3:06 AM EDT	Lake Wind Advisory	MLB	Lake, Okeechobee, Orange, Osceola, Seminole, Volusia	17 hr
Apr 20, 9:41 AM EDT	Special Weather Statement	MLB	Volusia	64 min
Apr 20, 10:12 AM EDT	Severe Thunderstorm Warning	MLB	Lake, Volusia	63 min
Apr 20, 10:32 AM EDT	Special Weather Statement	MLB	Lake	43 min
Apr 20, 10:38 AM EDT	Special Marine Warning	MLB		119 min
Apr 20, 10:42 AM EDT	Severe Thunderstorm Warning	MLB	Lake, Orange, Seminole, Volusia	63 min
Apr 20, 10:49 AM EDT	Tornado Warning	MLB	Volusia	26 min
Apr 20, 11:06 AM EDT	Tornado Warning	MLB	Lake, Orange, Seminole	24 min
Apr 20, 11:10 AM EDT	Severe Thunderstorm Warning	MLB	Seminole, Volusia	50 min
Apr 20, 11:13 AM EDT	Tornado Warning	MLB	Volusia	32 min
Apr 20, 11:28 AM EDT	Tornado Warning	MLB	Orange, Seminole	32 min
Apr 20, 11:32 AM EDT	Special Marine Warning	MLB		2 hr
Apr 20, 11:44 AM EDT	Severe Thunderstorm Warning	MLB	Brevard, Seminole, Volusia	46 min
Apr 20, 11:48 AM EDT	Tornado Warning Tornado observed	MLB	Brevard, Seminole, Volusia	42 min
Apr 20, 11:59 AM EDT	Tornado Warning	MLB	Brevard	31 min
Apr 20, 12:14 PM EDT	Tornado Warning	MLB	Brevard	31 min
Apr 20, 12:16 PM EDT	Tornado Warning	MLB	Brevard	29 min
Apr 20, 12:56 PM EDT	Special Weather Statement	MLB	Osceola	64 min
Apr 20, 1:05 PM EDT	Severe Thunderstorm Warning	MLB	Osceola	55 min
Apr 20, 1:52 PM EDT	Special Weather Statement	MLB	Brevard	53 min
Apr 20, 1:56 PM EDT	Special Marine Warning	MLB		68 min
Apr 20, 2:43 PM EDT	Special Weather Statement	MLB	Osceola	47 min
Apr 20, 3:02 PM EDT	Special Weather Statement	MLB	Okeechobee	58 min
Apr 20, 4:40 PM EDT	Special Marine Warning	MLB		2 hr
Apr 20, 4:44 PM EDT	Special Weather Statement	MLB	Okeechobee	46 min
Apr 20, 5:06 PM EDT	Special Weather Statement	MLB	Martin	39 min
Apr 20, 5:16 PM EDT	Severe Thunderstorm Warning	MLB	Martin, Saint Lucie	33 min
Apr 20, 5:41 PM EDT	Special Marine Warning	MLB		49 min

Nearby

Tornado Warnings in Florida, 2020 Every tornado warning in 2020 Tornadoes 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.