Alert archive / Florida / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 60, NWS Tampa Bay, FL

August 19, 2002Pinellas County, Florida

NWS Tampa Bay, FL issued this severe thunderstorm warning at Aug 19, 2002, 1:06 PM EDT for Pinellas County, Florida. It was in force for 24 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
Aug 19, 2002, 1:06 PM EDT (17:06 UTC)
Expired
Aug 19, 2002, 1:30 PM EDT
In force
24 min
Issued by
NWS Tampa Bay, FL
Area
Counties, with a storm outline in the text

County Pinellas County, FL

The radar

The Tampa radar (KTBW), 37 km from the middle of the area, began a volume at 17:08 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

TimeReportWhereRemark
Aug 19, 1:17 PM EDTHail 1.75Pinellas Park, FLNumerous reports of dime to golfball size hail due to a slow moving thunderstorm.

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.

Did it verify

Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this severe thunderstorm warning while it was in force. That is not proof nothing happened: reports are thin where few people live.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The nearest sounding before it

Tampa Bay, FL (KTBW), launched 12:00Z, 5.1 hours before the alert went out and 37 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 2002-08-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1782 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Tampa Bay, FL at 12:00Z on 2002-08-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -3 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
1782 J/kg
Mixed-layer CIN
-36 J/kg
Mixed-layer LCL
814 m above ground
0-6 km bulk shear
13 kt
0-1 km storm-relative helicity
-3 m²/s²
0-3 km storm-relative helicity
-9 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

816 
WUUS52 KTBW 191706
SVRTBW
FLC103-191730-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TAMPA BAY AREA - RUSKIN FL
105 PM EDT MON AUG 19 2002

THE NATIONAL WEATHER SERVICE IN RUSKIN HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHERN PINELLAS COUNTY IN FLORIDA.

* UNTIL 130 PM EDT

* AT 105 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM WITH LARGE HAIL AND DAMAGING WINDS...OVER
  LARGO...MOVING SOUTHEAST AT 5 MPH.

AT 1257 PM EDT...WEATHER SPOTTERS ALSO REPORTED PEA SIZE HAIL WITH 
THIS STORM

FREQUENT CLOUD TO GROUND LIGHTNING IS OCCURRING WITH THIS STORM. MOVE
INDOORS IMMEDIATELY. DO NOT USE ELECTRICAL APPLIANCES OR TELEPHONES.

&&

LAT...LON 2800 8272 2791 8289 2768 8276 2780 8255

$$

57

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Tampa Bay, FL wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 19, 9:30 AM EDT, 3 hours 36 minutes earlier.

Area forecast discussion, Aug 19, 9:30 AM EDT, 3 hours 36 minutes before
WEST CENTRAL AND SOUTHWEST FLORIDA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAMPA BAY AREA - RUSKIN FL
930 AM EDT MON AUG 19 2002

LATEST LAPS STREAMLINE ANALYSIS PLACES THE SFC RIDGE AXIS JUST NORTH
OF THE LAKE EARLY THIS MORNING WITH SFC OBS INDICATING A LIGHT SELY
FLOW ACROSS MY SRN ZONES...NEAR CALM CENTRAL...AND LIGHT S-SWLY TO
THE NORTH. POSITION OF RIDGE AXIS WILL FAVOR AN EARLY ONSET TO THE
WEST COAST SEA BREEZE TODAY...MOVING INLAND FASTER TO THE NORTH AND
HANGING CLOSER TO THE COAST AS ONE MOVES SOUTH.

12Z RAOB DATA INDICATES FAIRLY UNIFORM PWS (2) THROUGHOUT...SO
SHOULD SEE ANOTHER ROUND OF SHOWERS/STORMS THIS AFTERNOON AS MESO-
SCALE BOUNDARY INTERACTIONS TAKE PLACE. WEAK AND CHAOTIC STEERING
FLOW CENTRAL AND SOUTHERN ZONES WILL FAVOR STORMS PROPAGATING ALONG
SEA/LAKE/OUTFLOW BOUNDARIES...WHILE FURTHER NORTH A SLIGHTLY BETTER
SW-WLY STEERING WILL PUSH CONVECTION TOWARD INLAND LOCATIONS. IN
ADDITION SLOW MOVING CELLS WILL FAVOR LOCALLY HEAVY RAINS. ONGOING
ZONES SEEM TO HAVE A GOOD HANDLE ON THIS SO NO UPDATES ARE PLANNED.

MARINE...SFC RIDGE POSITION WILL SUPPORT LIGHT AND VARIABLE WINDS AND
SLIGHT SEAS OVER THE COASTAL WATERS THIS AFTERNOON. OTHER THAN MINOR
WIND WORDING ADJUSTMENTS TO FIT THE AFTERNOON...NO CHANGES EXPECTED.

.TBW...NONE.

MCMICHAEL

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 19, 1:31 PM EDTSevere Thunderstorm WarningTBWPinellas29 min

Nearby

Severe Thunderstorm Warnings in Florida, 2002Every severe thunderstorm warning in 2002

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.