Alert archive / Florida / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 25, NWS Tampa Bay, FL

August 12, 20214 counties in Florida

NWS Tampa Bay, FL issued this severe thunderstorm warning at Aug 12, 2021, 5:41 PM EDT for 4 counties in Florida. It was in force for 21 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Aug 12, 2021, 5:41 PM EDT (21:41 UTC)
Expired
Aug 12, 2021, 6:02 PM EDT
In force
21 min
Issued by
NWS Tampa Bay, FL
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

Counties Hardee County, FL, Hillsborough County, FL, Manatee County, FL, Polk County, FL

The radar

The Tampa radar (KTBW), 44 km from the middle of the area, began a volume at 21:41 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

Tampa Bay, FL (KTBW), launched 12:00Z, 9.7 hours before the alert went out and 44 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-pSkew-T log-p diagram, Tampa Bay, FL at 12:00Z on 2021-08-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1240 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Tampa Bay, FL at 12:00Z on 2021-08-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -35 square meters per square second.1939Sfc1 km3 km6 km9 kmRMLM
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
1240 J/kg
Mixed-layer CIN
-55 J/kg
Mixed-layer LCL
1012 m above ground
0-6 km bulk shear
5 kt
0-1 km storm-relative helicity
-35 m²/s²
0-3 km storm-relative helicity
-39 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

824 
WUUS52 KTBW 122141
SVRTBW
FLC049-057-081-105-122215-
/O.NEW.KTBW.SV.W.0025.210812T2141Z-210812T2215Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Tampa Bay Area Ruskin FL
541 PM EDT Thu Aug 12 2021

The National Weather Service in Ruskin has issued a

* Severe Thunderstorm Warning for...
  Northwestern Hardee County in central Florida...
  Northeastern Manatee County in west central Florida...
  Southwestern Polk County in central Florida...
  Eastern Hillsborough County in west central Florida...

* Until 615 PM EDT.

* At 541 PM EDT, a severe thunderstorm was located near Ona, or 8
  miles west of Wauchula, moving west at 10 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Duette and Fort Green. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 2763 8185 2751 8187 2749 8218 2775 8210
TIME...MOT...LOC 2141Z 106DEG 11KT 2757 8194 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

TBW
1 follow-up statement
996 
WWUS52 KTBW 122202
SVSTBW

Severe Weather Statement
National Weather Service Tampa Bay Area Ruskin FL
602 PM EDT Thu Aug 12 2021

FLC049-057-081-105-122212-
/O.CAN.KTBW.SV.W.0025.000000T0000Z-210812T2215Z/
Hardee FL-Manatee FL-Polk FL-Hillsborough FL-
602 PM EDT Thu Aug 12 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHWESTERN HARDEE...
NORTHEASTERN MANATEE...SOUTHWESTERN POLK AND EASTERN HILLSBOROUGH
COUNTIES IS CANCELLED...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning has been cancelled.  However gusty winds and
heavy rain are still possible with this thunderstorm.

LAT...LON 2763 8185 2751 8187 2749 8218 2775 8210
TIME...MOT...LOC 2155Z 106DEG 11KT 2759 8201 

$$

TBW

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 12, 3:56 PM EDTSpecial Marine WarningTBW49 min
Aug 12, 4:16 PM EDTSpecial Weather StatementTBWHillsborough44 min
Aug 12, 4:33 PM EDTSpecial Weather StatementTBWSumter42 min
Aug 12, 5:01 PM EDTSpecial Weather StatementTBWPasco, Pinellas44 min
Aug 12, 5:02 PM EDTSpecial Weather StatementTBWManatee43 min
Aug 12, 5:04 PM EDTSpecial Marine WarningTBW56 min
Aug 12, 5:32 PM EDTSpecial Weather StatementTBWHardee28 min
Aug 12, 5:36 PM EDTSevere Thunderstorm WarningTBWHillsborough, Pinellas24 min
Aug 12, 5:52 PM EDTSpecial Weather StatementTBWManatee38 min
Aug 12, 5:53 PM EDTSpecial Weather StatementTBWPasco37 min
Aug 12, 5:57 PM EDTSevere Thunderstorm WarningTBWManatee, Sarasota37 min
Aug 12, 5:59 PM EDTSpecial Marine WarningTBW61 min
Aug 12, 6:00 PM EDTSpecial Marine WarningTBW45 min
Aug 12, 6:29 PM EDTSpecial Weather StatementTBWHillsborough46 min
Aug 12, 6:59 PM EDTSpecial Marine WarningTBW31 min

Nearby

Severe Thunderstorm Warnings in Florida, 2021Every 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.