Alert archive / Florida / Severe Thunderstorm Warnings in 2004

Severe Thunderstorm Warning 83, NWS Tampa Bay, FL

August 30, 2004Polk County, Florida

NWS Tampa Bay, FL issued this severe thunderstorm warning at Aug 30, 2004, 4:41 PM EDT for Polk County, Florida. It was in force for 34 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 30, 2004, 4:41 PM EDT (20:41 UTC)
Expired
Aug 30, 2004, 5:15 PM EDT
In force
34 min
Issued by
NWS Tampa Bay, FL
Area
Counties, with a storm outline in the text

County Polk County, FL

The radar

The Tampa radar (KTBW), 60 km from the middle of the area, began a volume at 20:45 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.

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, 8.7 hours before the alert went out and 60 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 2004-08-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1999 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 2004-08-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 42 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
1999 J/kg
Mixed-layer CIN
-10 J/kg
Mixed-layer LCL
770 m above ground
0-6 km bulk shear
17 kt
0-1 km storm-relative helicity
42 m²/s²
0-3 km storm-relative helicity
25 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.

000 
WUUS52 KTBW 302041
SVRTBW
FLC105-302115-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TAMPA BAY AREA - RUSKIN FL
441 PM EDT MON AUG 30 2004

THE NATIONAL WEATHER SERVICE IN RUSKIN HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  CENTRAL POLK COUNTY IN FLORIDA.

* UNTIL 515 PM EDT

* AT 441 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM WITH LARGE HAIL AND DAMAGING WINDS...5 MILES
  SOUTHEAST OF BARTOW...MOVING NORTH AT 5 MPH.

* THE SEVERE THUNDERSTORM WILL AFFECT...
  BARTOW.
  WAHNETA.

SEVERE THUNDERSTORMS CONTAIN WIND GUSTS OF 60 MPH OR HIGHER...AND
HAIL THE SIZE OF PENNIES OR LARGER. MOVE TO A PLACE OF SAFETY.

&&

LAT...LON 2776 8191 2774 8173 2796 8166 2796 8183

$$

25

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 30, 1:54 PM EDT, 2 hours 47 minutes earlier.

Area forecast discussion, Aug 30, 1:54 PM EDT, 2 hours 47 minutes before
WEST CENTRAL AND SOUTHWEST FLORIDA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAMPA BAY AREA - RUSKIN FL
154 PM EDT MON AUG 30 2004

.SHORT TERM (TONIGHT-WED)...UPPER RIDGE BUILDS IN ACROSS FL FROM THE
ATLANTIC THROUGH THE PERIOD...GENERALLY SUPPRESSING PCPN ODDS SOME
AND KEEPING MAX TEMPERATURES ON THE WARM SIDE. ETA MOS HAS BEEN
HANDLING TEMPS BETTER THAN THE GFS MOS AND WILL TREND TOWARD THOSE
VALUES...BUT WILL UNDERCUT THE MAXES FROM THE LATEST RUN BY 1-2
DEGREES. A SURFACE RIDGE BUILDING IN ACROSS S FL WILL SLOWLY DRIFT
NORTH...REACHING N FL BY LATE WED. THIS RESULTS IN LOW LEVEL FLOW
BACKING FROM SW-W TO SE TO NE AS THE RIDGE AXIS MOVES UP THE CWFA
AND HURRICANE FRANCES APPROACHES FROM THE SOUTHEAST. HOWEVER COASTAL
LOCATIONS CAN EXPECT TO SEE WEST WINDS IN AFTERNOON SEA BREEZES. AS
THE WESTERLY FLOW GRADUALLY SHIFTS...PRECIP TIMING IN THE EARLY TO
MID MORNINGS SLOWLY GIVES WAY TO LATE MORNING AND EARLY AFTERNOON.

.LONG TERM (WED NIGHT-MON)...BY THURSDAY AND FRIDAY...WINDS WILL
TURN TO THE NORTHEAST AS SURFACE RIDGE BUILDS OVER THE NORTHEAST AND
MID ATLANTIC. CIRCULATION OF FRANCES WILL BE CREEPING CLOSER AS
WELL BASED ON LATEST FORECAST TRACK FROM HURRICANE CENTER. POPS ARE
A QUESTION AS SUBSIDENCE ON WEST SIDE OF HURRICANE COULD BECOME A
FACTOR. MADE NO CHANGES TO ONGOING FORECAST IN THIS RESPECT.

THE HOLIDAY WEEKEND IS COMPLETELY UP IN THE AIR DEPENDING UPON THE
ULTIMATE DESTINATION OF FRANCES. WENT GENERALLY WITH THE 06Z GFS FOR
THE GRIDS/ZONES...WHICH IS SIMILAR TO CURRENT HPC/TPC THINKING.

&&

.MARINE...NO HIGHLIGHTS EXPECTED AS SW-W WINDS SLOWLY BACK TO NE BY
THE END OF THE WEEK AS A SURFACE RIDGE AXIS MOVES NORTH OVER THE
COASTAL WATERS AND HURRICANE FRANCES APPROACHES FROM THE SE.
HOWEVER A AFTERNOON SEA BREEZE WILL SHIFT WINDS TO ONSHORE THE
NEXT COUPLE OF DAYS. GOING INTO THE WEEKEND...HOWEVER...WINDS
INCREASE AS FRANCES APPROACHES...AND WILL USE TS CONDITIONS POSSIBLE
FOR SAT.

&&

.FIRE WEATHER...NO CONCERNS.

&&

.PRELIMINARY POINT TEMPS/POPS...
TPA 77 91 76 91 / 20 40 20 40
FMY 76 92 75 92 / 20 40 20 40
GIF 75 93 75 92 / 20 40 20 40
SRQ 76 90 75 91 / 20 40 20 40
BKV 71 91 70 91 / 20 40 20 40

&&

.TBW WATCHES/WARNINGS/ADVISORIES...NONE.

&&

SHORT TERM...RKR
LONG  TERM...FWA
Hazardous weather outlook, Aug 30, 5:35 AM EDT, 11 hours 6 minutes before
HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TAMPA BAY AREA - RUSKIN FL
535 AM EDT MON AUG 30 2004

FLZ039-042-043-048>052-055>057-060>062-065-301230-
CHARLOTTE-CITRUS-DE SOTO-HARDEE-HERNANDO-HIGHLANDS-HILLSBOROUGH-LEE-
LEVY-MANATEE-PASCO-PINELLAS-POLK-SARASOTA-SUMTER-
535 AM EDT MON AUG 30 2004

THIS HAZARDOUS WEATHER OUTLOOK IS FOR WEST CENTRAL AND SOUTHWEST
FLORIDA.

.DAY ONE...TODAY:

SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE TO DEVELOP AND
MOVE INLAND THROUGH THIS AFTERNOON AS LOW LEVEL MOISTURE AND
INSTABILITY COMBINE. DRIER AIR ALOFT WILL KEEP COVERAGE OF THE
STORMS LIMITED...HOWEVER A FEW OF THESE STORMS COULD BE LOCALLY
STRONG WITH FREQUENT CLOUD TO GROUND LIGHTNING AND BRIEF HEAVY
DOWNPOURS BEING THE MAIN HAZARDS. MINOR FLOODING OVER LOW LYING AND
POORLY DRAINED AREAS IS POSSIBLE.

WHEN SKIES DARKEN...MOVE INDOORS. IF THERE IS TIME...UNPLUG
APPLIANCES AND ELECTRICAL EQUIPMENT. WAIT UNTIL THE STORM ENDS BEFORE
USING THE TELEPHONE OR RUNNING WATER.

STAY TUNED TO NOAA WEATHER RADIO OR YOUR LOCAL MEDIA OUTLETS FOR
UPDATES.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY:

SCATTERED THUNDERSTORMS ARE EXPECTED TO DEVELOP ALONG AFTERNOON SEA
BREEZE BOUNDARIES EACH DAY THROUGH FRIDAY AS HIGH PRESSURE BUILDS
OVER THE STATE. THE MAIN HAZARD WITH THESE STORMS WILL AGAIN BE
LOCALLY HEAVY DOWNPOURS AND FREQUENT CLOUD TO GROUND LIGHTNING.

THERE WILL BE A GREATER CHANCE FOR SHOWERS AND THUNDERSTORMS OVER
THE WEEKEND AS HURRICANE FRANCES MOVES WEST-NORTHWEST AND APPROACHES
THE NORTHERN BAHAMAS BY LATE FRIDAY. INTERESTED PARTIES SHOULD
MONITOR THE LATEST INFORMATION FROM THE NATIONAL HURRICANE CENTER
OVER THE NEXT SEVERAL DAYS AS FRANCES APPROACHES THE BAHAMAS.

.SPOTTER CALL TO ACTION STATEMENT...

SPOTTER ACTIVATION WILL NOT BE NEEDED.

&&

FOR ADDITIONAL WEATHER INFORMATION...CHECK OUR WEB SITE AT
HTTP://WWW.SRH.NOAA.GOV/TBW (LOWER CASE)

In the hours before

Special weather statement, Aug 30, 12:41 PM EDT, 4 hours before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE TAMPA BAY AREA - RUSKIN FL
1241 PM EDT MON AUG 30 2004

FLZ043-048-049-301730-
HERNANDO-PASCO-SUMTER-
1241 PM EDT MON AUG 30 2004

...STRONG THUNDERSTORMS WILL AFFECT DADE CITY...
A THUNDERSTORM...MOVING EAST AT 10 MPH...WILL AFFECT DADE
CITY...DADE CITY NORTH...RIDGE MANOR AND LACOOCHEE...UNTIL 130 PM
EDT. GUSTY WINDS 40 TO 50 MPH MAY CAUSE LOOSE OBJECTS TO BLOW
AROUND. MINOR DAMAGE TO TREE LIMBS AND WIRES IS POSSIBLE. FREQUENT
CLOUD TO GROUND LIGHTNING IS EXPECTED. IF CAUGHT OUTSIDE...CROUCH
DOWN IN A LOW SPOT...AWAY FROM TALL OBJECTS.
Special weather statement, Aug 30, 1:05 PM EDT, 3 hours 36 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE TAMPA BAY AREA - RUSKIN FL
105 PM EDT MON AUG 30 2004

FLZ051-052-301745-
HILLSBOROUGH-POLK-
105 PM EDT MON AUG 30 2004

...STRONG THUNDERSTORMS WILL AFFECT NORTHEAST HILLSBOROUGH INTO
NORTHWEST POLK COUNTY...
THUNDERSTORMS...MOVING NORTHEAST AT 15 MPH...WILL AFFECT
THONOTOSASSA...HILLSBOROUGH RIVER STATE PARK...WINSTON AND
KATHLEEN...UNTIL 145 PM EDT. GUSTY WINDS UP TO 40 MPH WILL OCCUR.
FREQUENT CLOUD TO GROUND LIGHTNING IS EXPECTED. IF CAUGHT
OUTSIDE...CROUCH DOWN IN A LOW SPOT...AWAY FROM TALL OBJECTS.
TORRENTIAL RAINS WILL CAUSE PONDING OF WATER ON ROADS...AND MINOR
FLOODING OF POOR DRAINAGE AREAS.

CLOSE
Special weather statement, Aug 30, 4:39 PM EDT, 2 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE TAMPA BAY AREA - RUSKIN FL
439 PM EDT MON AUG 30 2004

FLZ052-302130-
POLK-
439 PM EDT MON AUG 30 2004

...STRONG THUNDERSTORMS WILL AFFECT SOUTH CENTRAL POLK COUNTY...
MOVING NORTHEAST AT 10  MPH...WILL AFFECT BARTOW AND WAHNETA...UNTIL
530 PM EDT. GUSTY WINDS 40 TO 50 MPH MAY CAUSE LOOSE OBJECTS TO BLOW
AROUND. MINOR DAMAGE TO TREE LIMBS AND WIRES IS POSSIBLE. EXCESSIVE
CLOUD TO GROUND LIGHTNING IS EXPECTED IF OUTSIDE...CROUCH DOWN IN A
LOW SPOT...AWAY FROM TALL OBJECTS. IF INDOORS...REFRAIN FROM USING
ELECTRICAL APPLIANCES. HAIL UP TO ONE HALF INCH IN DIAMETER IS
EXPECTED.

DAVIS

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 30, 4:32 PM EDTTornado WarningTBWHardee28 min

Nearby

Severe Thunderstorm Warnings in Florida, 2004Every severe thunderstorm warning in 2004

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.