Alert archive / Florida / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 9, NWS Tampa Bay, FL

April 11, 2021Highlands County, Florida

NWS Tampa Bay, FL issued this severe thunderstorm warning at Apr 11, 2021, 1:47 PM EDT for Highlands County, Florida. It was in force for 28 min. 2 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 11, 2021, 1:47 PM EDT (17:47 UTC)
Expired: Apr 11, 2021, 2:15 PM EDT
In force: 28 min
Issued by: NWS Tampa Bay, FL
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

County Highlands County, FL

The radar

The Melbourne radar (KMLB), 92 km from the middle of the area, began a volume at 17:47 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 11, 2:05 PM EDT	HAIL 0.7	1 Ene Placid Lakes, FL
Apr 11, 2:22 PM EDT	TSTM WND GST 54	10 Nne Lorida, FL	MESONET STATION APRF1 AVON PARK AF RANGE 1.

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

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Apr 11, 8:15 AM EDT	Severe Thunderstorm Watch	SPC	8 hr

The nearest sounding before it

Tampa Bay, FL (KTBW), launched 12:00Z, 5.8 hours before the alert went out and 121 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: 1004 J/kg
Mixed-layer CIN: -131 J/kg
Mixed-layer LCL: 1005 m above ground
0-6 km bulk shear: 57 kt
0-1 km storm-relative helicity: 288 m²/s²
0-3 km storm-relative helicity: 296 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.3

Open this sounding in Storm Lab

The text

As transmitted.

036 
WUUS52 KTBW 111747
SVRTBW
FLC055-111815-
/O.NEW.KTBW.SV.W.0009.210411T1747Z-210411T1815Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Tampa Bay Area Ruskin FL
147 PM EDT Sun Apr 11 2021

The National Weather Service in Ruskin has issued a

* Severe Thunderstorm Warning for...
  Highlands County in south central Florida...

* Until 215 PM EDT.

* At 146 PM EDT, severe thunderstorms were located along a line
  extending from 5 miles west of Kissimmee Prarie Preserve to 10
  miles southwest of Sebring, moving east at 40 mph.

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

  SOURCE...Trained weather spotters.

  IMPACT...Hail damage to vehicles is expected. Expect wind damage 
           to roofs, siding, and trees.

* Locations impacted include...
  Sebring, Avon Park, Lake Placid, Sebring Regional Airport, Sylvan
  Shores, Lake Istokpoga, Cornwell, Sebring Shores, Lake Josephine,
  Lorida, Avon Park Executive Airport, Avon Park Air Force Range and
  Placid Lakes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 2734 8105 2725 8124 2725 8156 2755 8156
      2765 8152 2764 8114 2760 8114 2756 8118
      2755 8121 2749 8121 2744 8114 2741 8114
      2739 8112 2738 8107 2736 8103
TIME...MOT...LOC 1746Z 279DEG 35KT 2761 8118 2735 8155 

HAIL...1.00IN
WIND...60MPH
 
$$

TBW

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 11, 3:32 AM EDT	Small Craft Advisory	TBW		16 hr
Apr 11, 5:46 AM EDT	Special Weather Statement	TBW	Gilchrist	44 min
Apr 11, 9:13 AM EDT	Special Marine Warning	TBW		92 min
Apr 11, 9:14 AM EDT	Rip Current Statement	TBW	Charlotte, Hillsborough, Lee, Manatee, Pinellas, Sarasota	15 hr
Apr 11, 9:28 AM EDT	Special Weather Statement	TBW	Hernando	47 min
Apr 11, 10:44 AM EDT	Special Marine Warning	TBW		61 min
Apr 11, 11:09 AM EDT	Severe Thunderstorm Warning	TBW	Hernando, Hillsborough, Pasco, Pinellas, Sumter	32 min
Apr 11, 11:49 AM EDT	Special Marine Warning	TBW		56 min
Apr 11, 11:56 AM EDT	Special Weather Statement	TBW	Hillsborough, Polk	64 min
Apr 11, 12:23 PM EDT	Special Weather Statement	TBW	Hillsborough, Pinellas	37 min
Apr 11, 1:01 PM EDT	Severe Thunderstorm Warning	TBW	Hardee, Hillsborough, Manatee, Polk	29 min
Apr 11, 1:32 PM EDT	Special Weather Statement	TBW	Hardee, Highlands	43 min
Apr 11, 3:13 PM EDT	Special Marine Warning	TBW		62 min
Apr 11, 3:41 PM EDT	Special Weather Statement	TBW	Charlotte, Lee	49 min
Apr 11, 4:08 PM EDT	Severe Thunderstorm Warning	TBW	Lee	17 min

Nearby

Severe Thunderstorm Warnings in Florida, 2021 Every severe thunderstorm 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.