Alert archive / Florida / Severe Thunderstorm Warnings in 2019

Severe Thunderstorm Warning 13, NWS Melbourne, FL

April 6, 2019Seminole County, Volusia County, Florida

NWS Melbourne, FL issued this severe thunderstorm warning at Apr 6, 2019, 8:09 PM EDT for Seminole County, Volusia County, Florida. It was in force for 51 min. 1 report 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 6, 2019, 8:09 PM EDT (00:09 UTC)
Expired: Apr 6, 2019, 9:00 PM EDT
In force: 51 min
Issued by: NWS Melbourne, FL
Area: Storm-based polygon
Hail: 0.88 in
Wind: 60.0 mph

Counties Seminole County, FL, Volusia County, FL

The radar

The Melbourne radar (KMLB), 108 km from the middle of the area, began a volume at 00:10 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 6, 8:16 PM EDT	TSTM WND GST 41	4 Nnw Lake Jessup, FL	TSTM WIND GUST OF 41 MPH/36 KNOTS FROM THE NORTH/360 DEGREES AT KSFB/SANFORD AIRPORT.

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 00:00Z, 0.2 hours before the alert went out and 94 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: 236 J/kg
Mixed-layer CIN: -128 J/kg
Mixed-layer LCL: 1463 m above ground
0-6 km bulk shear: 21 kt
0-1 km storm-relative helicity: -59 m²/s²
0-3 km storm-relative helicity: 8 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -1.1

Open this sounding in Storm Lab

The text

As transmitted.

629 
WUUS52 KMLB 070009
SVRMLB
FLC117-127-070100-
/O.NEW.KMLB.SV.W.0013.190407T0009Z-190407T0100Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Melbourne FL
809 PM EDT SAT APR 6 2019

The National Weather Service in Melbourne has issued a

* Severe Thunderstorm Warning for...
  Northwestern Seminole County in east central Florida...
  South central Volusia County in east central Florida...

* Until 900 PM EDT.

* At 809 PM EDT, a severe thunderstorm was located over DeBary,
  moving southeast at 10 mph.

  HAZARD...60 mph wind gusts and nickel size hail.

  SOURCE...Radar indicated.

  IMPACT...Expect damage to roofs, siding, and trees.

* Locations impacted include...
  Deltona, Sanford, Winter Springs, Lake Mary and Orange City. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

Intense thunderstorm lines can produce brief tornadoes and widespread
significant wind damage. Although a tornado is not immediately
likely, it is best to move to an interior room on the lowest floor of
a building. This storm may cause serious injury and significant
property damage.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 2893 8114 2868 8123 2875 8142 2879 8141
      2883 8142 2886 8138 2887 8137 2889 8137
      2889 8135 2892 8136 2892 8135 2894 8135
      2896 8136 2896 8137 2897 8137
TIME...MOT...LOC 0009Z 298DEG 10KT 2889 8135 

HAIL...0.88IN
WIND...60MPH
 
$$

Johnson

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 6, 8:48 PM EDT	Special Weather Statement	MLB	Seminole	42 min
Apr 6, 8:52 PM EDT	Severe Thunderstorm Warning	MLB	Lake, Seminole, Volusia	37 min
Apr 6, 9:15 PM EDT	Special Weather Statement	MLB	Seminole	45 min

Nearby

Severe Thunderstorm Warnings in Florida, 2019 Every severe thunderstorm warning in 2019

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.