Alert archive / Florida / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 101, NWS Tampa Bay, FL

May 5, 1998Polk County, Florida

NWS Tampa Bay, FL issued this severe thunderstorm warning at May 5, 1998, 10:39 AM EDT for Polk County, Florida. It was in force for 46 min. 2 reports came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued
May 5, 1998, 10:39 AM EDT (14:39 UTC)
Expired
May 5, 1998, 11:25 AM EDT
In force
46 min
Issued by
NWS Tampa Bay, FL
Area
Whole counties

County Polk County, FL

The radar

The Tampa radar (KTBW), 74 km from the middle of the area, began a volume at 14:38 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
May 5, 10:58 AM EDTHail 0.75Lakeland, FLDime sized hail was reported in South Lakeland by a Skywarn Spotter.
May 5, 11:16 AM EDTHail 1Auburndale, FL

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.

The nearest sounding before it

Tampa Bay, FL (KTBW), launched 12:00Z, 2.7 hours before the alert went out and 74 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 1998-05-05Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1588 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 1998-05-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 84 square meters per square second.19395878Sfc1 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
1588 J/kg
Mixed-layer CIN
-24 J/kg
Mixed-layer LCL
808 m above ground
0-6 km bulk shear
40 kt
0-1 km storm-relative helicity
84 m²/s²
0-3 km storm-relative helicity
157 m²/s²
Significant tornado parameter
0.0
Supercell composite
4.6

Open this sounding in Storm Lab

The text

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

074 
WUUS1 KTBW 051440 RRA
SVRTBW
FLC105-051525-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TAMPA BAY AREA - RUSKIN FL
1039 AM EDT TUE MAY 5 1998

THE NATIONAL WEATHER SERVICE IN RUSKIN HAS ISSUED A

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

* UNTIL 1125 AM EDT

* AT 1035 AM EDT... A SEVERE THUNDERSTORM 8 MILES SOUTH OF PLANT
  CITY... WAS INDICATED BY NATIONAL WEATHER SERVICE DOPPLER RADAR IN
  RUSKIN... MOVING EAST 30 MPH.

* THIS SEVERE THUNDERSTORM IS EXPECTED TO BE NEAR...
  MULBERRY                 AROUND 1050 AM EDT
  HIGHLAND CITY            AROUND 1100 AM EDT
  BARTOW                   AROUND 1105 AM EDT

THESE STORMS HAVE HAD A HISTORY OF PRODUCING DIME AND NICKEL SIZED
HAIL.

SEVERE THUNDERSTORMS PRODUCE STRONG DAMAGING WINDS IN EXCESS OF 58
MPH AND/OR LARGE HAIL. MOVE INDOORS TO A STURDY BUILDING... MOBILE
HOMES ARE NOT SAFE.

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 May 5, 10:10 AM EDT, 29 minutes earlier.

Area forecast discussion, May 5, 10:10 AM EDT, 29 minutes before
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAMPA BAY-RUSKIN, FL
1010 AM EDT TUE MAY 5 1998

WEATHER GOING DOWN HILL FASTER THAN YESTERDAY. HAVE ALREADY AMENDED
ZONES TO REMOVE AFTN WORDING SINCE STORMS ALREADY ACTIVE. ATMOS AGAIN
VERY UNSTABLE WITH LI OF -8 AND CAPES OVER 2500 LOOKING ON LATEST
SFC AND SAT DATA...WK CLD BNDRY AND SFC TD GRADIENT COINCIDE OVER NCENT
FA FM ABT DAB TO CITRUS CO. THUS...CHC OF STORMS STILL EXISTS SOUTH
OF THIS AREA. BEST CHC WILL BE CENT AND S FA WHERE INSTABILITY IS
GREATEST. ALREADY GETTING DIME-SIZED AND LARGER HAIL THIS MORNING
FM STORMS OVER PINELLAS AND MANATEE COUNTIES. THANKS MLB FOR COORD.
SINCE STORMS ALREADY IN PROGRESS...WILL NOT BOTHER UPDATING HWO.

MORALES

In the hours before

Special weather statement, May 5, 5:45 AM EDT, 4 hours 54 minutes before
FLZ039-042-043-048>052-055>057-060>062-065-051530-

WEST CENTRAL AND SOUTHWEST FLORIDA HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TAMPA BAY AREA - RUSKIN FL
545 AM EDT TUE MAY 5 1998

...WIDELY SCATTERED THUNDERSTORMS OVER CENTRAL AND SOUTH FLORIDA...

DAYTIME HEATING WITHIN A WARM AND MARGINALLY MOIST ATMOSPHERE OVER THE
PENINSULA WILL CREATE CONDITIONS FAVORABLE FOR THE GENERATION OF WIDELY
SCATTERED THUNDERSTORMS THIS TUESDAY AFTERNOON.

THE MORE FAVORABLE AREA FOR DEVELOPING THUNDERSTORMS WILL BE SOUTH OF
A LINE FROM CAPE CANAVERAL TO BARTOW TO CHARLOTTE HARBOR. ONLY ISOLATED
THUNDERSTORMS ARE POSSIBLE NORTHWARD TO WILDWOOD AND BROOKSVILLE.
THUNDERSTORMS WILL MOVE TO THE EAST AT 25 TO 30 MPH...TO THE FLORIDA
EAST COAST MID TO LATE AFTERNOON...THEN INTO THE ATLANTIC EARLY TONIGHT.

THUNDERSTORMS ARE NOT EXPECTED TO BE AS STRONG AS THOSE THAT OCCURRED
MONDAY AFTERNOON.  HOWEVER ALL THUNDERSTORMS ARE CAPABLE OF GENERATING
GUSTY WINDS...LOCAL DOWNPOURS...POSSIBLE HAIL...AND DEADLY LIGHTNING.

ALL PERSONS...PARTICULARLY THOSE IN INTERIOR CENTRAL AND SOUTH FLORIDA...
SHOULD BE ALERT TO LOCAL THUNDERSTORM DEVELOPMENT BEGINNING AROUND NOON
TODAY INTO THIS AFTERNOON.

RITTENBERRY
Special weather statement, May 5, 5:45 AM EDT, 4 hours 54 minutes before
FLZ039-042-043-048>052-055>057-060>062-065-051530-

WEST CENTRAL AND SOUTHWEST FLORIDA HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TAMPA BAY AREA - RUSKIN FL
545 AM EDT TUE MAY 5 1998

...WIDELY SCATTERED THUNDERSTORMS OVER CENTRAL AND SOUTH FLORIDA...

DAYTIME HEATING WITHIN A WARM AND MARGINALLY MOIST ATMOSPHERE OVER THE
PENINSULA WILL CREATE CONDITIONS FAVORABLE FOR THE GENERATION OF WIDELY
SCATTERED THUNDERSTORMS THIS TUESDAY AFTERNOON.

THE MORE FAVORABLE AREA FOR DEVELOPING THUNDERSTORMS WILL BE SOUTH OF
A LINE FROM CAPE CANAVERAL TO BARTOW TO CHARLOTTE HARBOR. ONLY ISOLATED
THUNDERSTORMS ARE POSSIBLE NORTHWARD TO WILDWOOD AND BROOKSVILLE.
THUNDERSTORMS WILL MOVE TO THE EAST AT 25 TO 30 MPH...TO THE FLORIDA
EAST COAST MID TO LATE AFTERNOON...THEN INTO THE ATLANTIC EARLY TONIGHT.

THUNDERSTORMS ARE NOT EXPECTED TO BE AS STRONG AS THOSE THAT OCCURRED
MONDAY AFTERNOON.  HOWEVER ALL THUNDERSTORMS ARE CAPABLE OF GENERATING
GUSTY WINDS...LOCAL DOWNPOURS...POSSIBLE HAIL...AND DEADLY LIGHTNING.

ALL PERSONS...PARTICULARLY THOSE IN INTERIOR CENTRAL AND SOUTH FLORIDA...
SHOULD BE ALERT TO LOCAL THUNDERSTORM DEVELOPMENT BEGINNING AROUND NOON
TODAY INTO THIS AFTERNOON.

RITTENBERRY

The office that day

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

IssuedProductOfficeCountiesLasted
May 5, 9:43 AM EDTSevere Thunderstorm WarningTBWHillsborough, Pinellas47 min
May 5, 10:31 AM EDTSevere Thunderstorm WarningTBWHillsborough49 min
May 5, 11:27 AM EDTSevere Thunderstorm WarningTBWPolk48 min
May 5, 12:51 PM EDTSevere Thunderstorm WarningTBWPolk49 min
May 5, 2:45 PM EDTSevere Thunderstorm WarningTBWManatee, Sarasota50 min

Nearby

Severe Thunderstorm Warnings in Florida, 1998Every severe thunderstorm warning in 1998

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.